CA1340294C - Fluorination of acetals, ketals and orthoesters - Google Patents

Abstract

This invention pertains to perhalogenated formals, acetals, ketals, orthoesters, perfluoro-polyethers and perhalogenated chlorofluoroether polymers and to methods for preparing them.

Description

1~0~94 FL~ORINATION OF AGETALS._KET~LS AND ORTHOESTERS

Back~round Perfluoropolyethers are highly regarded in the ~peci~lty lmbricant field because of thelr wide liqu~d ran~e~l low vapor pressure5 and high thermal and oxidat~ve ~t~billt~s. Because o$ the~e propert~os (msny of whlch are unique to fluoroc~rbons), they are excellent high performance lubricants, superlor base stocks for ~reases, ~xcellent lu~icat~ng olls, ~nd heat transfer flu~ds. ln sdd~tlon, because of these uniquely outst~nding propert~es. satur~ted perfluoropolyethers ~re of current interese as speci~lty sealAnts, ela~eomers and pl~stic~.
In splee of their unlimlted poten~lal, only three perfluoropolyethers ~r~ co~mercially av~ll8~1e to date bec~u~e o~ the lack of fl~orocarbon inter~edlates which are suitable for prepar~n~ the polymers, They are: -1. DuPont'~ Krytox~ flu~d ~hich is m~de bypolymerizing hexafluoropropyleno ox~de.

.. , .. ~

~ ~3 10294 2. Demnum~ fluid, a product of Daikin Industries, is obtained by ring opening polymerization of 2,2,3,3-tetrafluoro-oxetane using a catalyst with subsequent treatment of the highly fluorinated polyether with fluorine gas to give a perfluorinated product.

3. Montedison's Fomblin Z~ and Fomblin Y~
fluids which are prepared by photooxidizing tetrafluoroethylene and hexafluoropropylene oxide, respectively, in the presence of oxygen.
A process has been described for preparing perfluoropolyethers by reaction of a hydrocarbon polyether with elemental fluorine in the presence of a hydrogen fluoride scavenger. See U.S. Patent No.

4,755,567.

Summary of the Invention The present invention relates to perhalogenated polyethers having essentially the following formula:

X-[O~I~(O~CF2~~F)p]n~[OIC~(O-CF2-1CF)t]m-oz wherein R1, R2, R3, R4, Rs and R6 are the same or different and are selected from the group consisting of -F, -Cl, -CF2Cl, -CFC12, -CC13, perfluoroalkyl of one to ten carbon atoms, perfluoroalkoxyalkyl of one to ten carbon atoms and perfluoroalkoxyether of one to ten carbon atoms wherein one or more of the fluorine atoms can be substituted by a halogen atom other than fluorine; X and Z are the same or different and are selected from the group consisting of -(CF2)rCOF, -(CF2)rOCF3, -(CF2)rCOOH and 1~102!~ 1 -CrF2r+1_qClq~ wherein r is an integer from 1 to 12 and q is an integer from O to 25; n is an integer from 2 to 1,000; m is an integer from O to 1000; p and t are the same or different and are integers from 1 to 50, provided that when p and t are one and R1, R2, R3 and R4 together are F, then Rs or R6 is a group other than fluorine.
The invention also relates to perhalogenated polyethers of the formula:

IRl X-(o-c)n~~z (II) wherein X and Z are the same or different and are selected from the group consisting of -(CF2)rCOF, -(CF2)rOCF3, -(CF2)rCOOH and ~CrF2r+1_qClq~ wherein r is an integer from 1 to 12 and q is an integer from O
to 25; R1 and R2 are the same or different and are selected from the group consisting of -F, -Cl, -CF2Cl, -CFCl2, -CCl3, perfluoroalkyl of one to ten carbon atoms, perfluoroalkoxyalkyl of one to ten carbon atoms and perfluoroalkoxyether of one to ten carbon atoms wherein one or more of the fluorine atoms can be substituted by a halogen atom other than fluorine, provided that R1 and R2 together are not F;
and n is an integer from 2 to 1,000.
The invention also pertains to perhalogenated polyethers having the formula:

IRl Y--O--C--O--Y ' wherein Y and Y' are the same or different and are selected from the group consisting of perfluoroalkyl, ' ~3-10294 perfluoroalkoxyalkyl, perfluoroalkyleneoxyalkyl and perfluoroalkoxyether, preferably each having 1 to 50 carbon atoms and wherein one or more of the fluorine atoms can be halogen other than fluorine; R1 and R2 are the same or different and are selected from the group consisting of -F, -Cl, -CF2Cl, -CFCl2, -CCl3, perfluoroalkyl having one to twenty carbon atoms, perfluoroalkyleneoxyalkyl of one to ten carbon atoms and perfluoroalkoxy of one to ten carbon atoms, wherein one or more of the fluorine atoms can be substituted by a halogen atom other than fluorinei and wherein the polyether preferably comprises 12 or more carbon atoms.
A preferred perfluorinated polyether consists essentially of:
Y-O-CF2-0-Y ' wherein Y and Y' are the same or different and are selected from the group consisting of perfluoroalkyl of one to ten carbon atoms, perfluoroalkoxyalkyl of one to ten carbon atoms, perfluoroalkyleneoxyalkyl of one to ten carbon atoms and perfluoroalkoxyether of one to ten carbon atoms; wherein one or more of the fluorine atoms can be substituted by a halogen atom other than fluorine and wherein the polyether comprises less than 8 or at least 12 carbon atoms provided that Y and Y' cannot both be -CF3 or -C2Fs.
The perhalogenated polyethers of this invention can be used as lubricants, hydraulic fluids, thermal shock fluids, vapor phase soldering fluids and in numerous other applications in which an inert, nonflammable, oxidatively stable fluid is required.
The low molecular weight perfluoropolyethers of the present invention have many useful applications in the electronics industry.

-5- 13~029~
Detailed Description of the Invention In general, the perfluoropolyether and perhalogenated chlorofluoropolyether polymers have the formula:

Rl R3 X-[O-c-O-Y]n _ [~-C-~-Y']m - OZ (I) wherein Y and Y' are the same or different and are selected from the group consisting of linear and branched perfluoroalkylenes having at least 2 carbon atoms, preferably having 2 to 6 carbon atoms;
perfluoroalkyleneoxyalkylene and perfluoropoly-(alkyleneoxyalkylene) each having alkylene groups containing at least two carbon atoms, preferably having from 2 to 30 carbons and most preferably having 4 to 8 carbons; wherein in Y or Y' one or more of the fluorine atoms may be substituted by a halogen atom other than fluorine. Y and Y' can be isotactic perfluoropoly-ethers or atactic perfluoropolyethers, such as -CF2CF2CF2, -CF2CF2CF2CF2-,-CF2CF20CF2CF2-~
- CF2 ( CF3 ) CFOCF ( CF3 )CF2- and ~,~

-6- 1~029 l -CF2cF2~cF2cF2~cF2cF2- X and Z are the same or different and are selected from the group consisting of -(CF2)rCOF, -(CF2)rOCF3, -(CF2)rCOOH and CrF2r+1 qClq, wherein r is an integer from 1 to 12 and q is an integer from 0 to 25. R1, R2, R3 and R4 are the same or different and are selected from the group consisting of -F, -Cl, -CF2Cl, -CFCl2, -CCl3, perfluoroalkyl of one to ten carbon atoms, such as -CF3, -C2F5, -C3F7 and -C4Fg and perfluoroalkoxy-alkyl of one to ten carbon atoms, such as -OCF3 and F5~wherein one or more of the fluorine atoms in said perfluoroalkyl and perfluoroalkoxyalkyl may be substituted by a halogen atom other than fluorine.
Preferably R1 to R4 are F and -CF3 groups. n is an integer from 2 to 1,000; and m is an integer from 0 to 1,000; provided that when R1, R2, R3 and R4 together are F then Y or Y' comprises an ethylene group having at least one fluorine atom which is substituted with a halogen atom other than fluorine, preferably by chlorine.
The n and m subscripts of formula I are average indices of composition such that when m is zero the polyether is referred to as an alternating copolymer Rl (-O-C-) and (OY).

~ ~0294 When m ~nd n are gre~ter than zero, the polyether ~ 5 a texpoly~er contAining ( -O-C- ) ~2 groups havin~ ran~om OY and OY' units ~long the polymer chain. Th~ si~plest ~ember of this class of compounds is a 1:1 copolymer of difluoromethylene oxide and ~etrafluoroethylene oxide which is the subJect of U.S. Patent No. 4,760,198.
This invention lso relates to perfluoro-poly~ther~ and perhalogenated chlorofluoropolyether~
of Formula I where Y and Y' are polyethers and hsve the average formula:

Rl ~3 X-tO~ o-~F2-lF)p]n-~o-~-(o-cF2-cF)t] ~oz ~V

~herein Rl~ R2~ R3~ R4~ Rs and R6 are the same o~
different ~nd are selected from the g~oup con~is~in~
of -F, -Cl, -CF2Gl, CFCl2, -CC13, perfluoroalkyl of one to ten c~rbon atoms and perfluoraalkoxyalkyl of one to ten ~arbon atom~ where~n one or more of the fluorine atoms ~ay be substituted by a halogen ato~
ot~er t~an fluorine; wher~in X and 2 are the ~a~e or differe~t and are selected from the ~roup con-si~tlng of -~2)rC0~, -(CF~)rOCF3, -(CF2)rCOOH and CrF2r+l qClq wherein r i5 an integer fro~ l to -8- ~3'1029~

twelve and q is an integer from O to 25; wherein n is an integer from 2 to 1000, m is an integer from O
to 1000; and p and t are the same or different and are integers from 1 to 50, provided that when p and t are one and Rl, R2, R3 and R4 together are fluorine, then R5 or R6 is a group other than fluorine. Preferably, p and t are integers from 1 to 10 .
Examples of perfluoropolyethers where m in formula I is zero and p is an integer between 2 and 50 are shown below:

X-[O-CF2-(0-CF2-CF2)p]n-OZ

X-[O-CF -(O-CF -CF -CF ) ] -OZ

X-[O-CF-(O-CF2-CF2)p]n-oz X-[o-lc-(o-cF2-cF2)p]n~~z Examples of perfluorinated polyethers of formula I where m is zero, p is defined above and Y
is an isotactic perfluoropolyether or atactic perfluoropolyether are:

X-[O-CF2-(0-CF2-CF)p]n-oz ~ 3 ~029~

X ~o-cF2-(o-cF2 ~F)p3n C2F~

X~o-cF2(o-&F2cF)p]
CF2Cl ~ amples o~ ran~o~ copolymers of formula I in which m and n ~re greater than zero, and p is defined above, lnclude;

x.~o-CF2-~0-CF2~~F2)p]n~[~ C~2 ( 2 ~ t X- ~O-CF2- (0-CF2- ~CF)p~n- ~O-CF2 (0-CF2-~F~t]m-OZ

Perfl~oropolyethers an~ perhalogenated chloro-~luoropoly~thers can also be prepared which have the average formula:

FCt (OC~2-1 F~n-OX~3 or C~(OCF2-~F)n-OX~4 VI

whereLn X is ~elected from the group co~si~ting of ~ 2)r OOH, ~CF2)r F3~ ( 2~rC~~' and CrF2r+l q~l~ where ~ i~ an integor ~rom 1 to 12 and q is an In~ege~ fro~ O to 25. Preferably X ls -CF3, -C2F5, -CF2COOH, -CF20CF3 ~nd CF2coF; w~erein n i8 ~3~û294 an inte8er from 1 to 50; and wherein R ~s selecte~
from the group conC~sting of -F, -CF2Cl, -CFC12, CC13 and perfluoroalkyl of one to ten earbons.
T~is inven~lon fur~her pertai~s to perfluoro-polyether~ and perhalogenated chlorofl~oropolyether~
having the average formula:

Rl X ~0-Cln-OZ II

wherein Rl, R2, X ~nd Z are deflned above, and n is an integer f~om 2 to 1000; provided that Rl a~d ~2 cannot bo~ be fluorine atoms.
This invention ~lso pertains ~o the co~pounds shown below an~ to compo~nds consisting essentially of th~se~ formulae. -~he co~po~nds can b~
perfluor~nated formals wh~ch have the formula:

Y-O-CF2'~-Y' wherein Y and Y' ~re the same or d~fferen~ and ~re selected fro~ t~e group consis~in~ of perfl~oro-alky}, perfluoroalkoxyalkyl, and perfluoroalkylene-oxyalkyl; ~nd wherein t~e polyethe~ comprises fewer than 8 or, 12 or more carbon atoms provided ~hat Y
and Y' cannot ~oth b~ -CF3 or -C2F5. Pre~erably, the polye~her wIll comprise 12 to 20 carbon ~toms.
Perhalo~enated acetal compo~nds can also be made which having an average fo~ula:

y.o-CF-O-Y~

~ ~3i~029 1 whereln Y and Y' ar~ the same or differe~t and are selected fro~ the group consisting of perfluoro-alkyl, perfluoroalkoxyalkyl, and perfluoroalkylene-oxya}kyl; wh~rein R is ~elected from the group conslstin~ of -Gl, CF2Cl, -CFCl2, -CCl3, perfluoro-alkyl having 1 to 2~ carbon atoms and perfluoro-alkyleneoxyalkyl; and ~herein the polyether co~-pri~es 12 or more carbon atoms. Pre~ere~ly, the polyether will comp~ise from 12 to 50 carbon atom~
and more preferably, w~ll comprise 12 to 25 carbon atoms.
The invention also includes perhalogenated ketals having an a~erage formula:

Y-O-C-O-Y' ~2 where~n Y ~nd Y' sre ~he same or different and are selected fro~ the group conslsting of perfluoro-alkyl, perfluoroal~oxyalkyl, and perfluoroalkylene-oxyalkyl; whereln Rl and R2 ~re the sa~e or différent and are selected from t~e grOup cons~s~in~
of -Cl, CF2Cl, -CFCl2. -CC13, perfluoroalkyl havin~
1 .o 20 carbon atom~ and perfluoroal~yleneoxyalkyl;
and wherein the polyether comprises 12 or mo~e carbon atoms. Preferably, the polyether will comprLse 12 to 25 ca~on atoms.
~ he invention al~o pertain~ to ether~ ha~ing an ~verage formula:
~ 1 Y-O-C-O-Y' ~3~ 294 wherein Y and Y' are the same or different and are selected from the group consisting of perfluoro-alkyl, perfluoroalkoxyalkyl, and perfluoroalkylene-oxyalkyl; wherein R1 and R2 are the same or different and are selected from the group consisting of -F, -Cl, CF2Cl, -CFC12, -CC13, perfluoroalkyl having 1 to 20 carbon atoms and perfluoroalkylene-oxyalkyl; and wherein the polyether contains at least one halogen atom other than fluorine. The perfluoroalkylpolyether may be atactic, isotactic or a block copolymer having l to 50 carbon atoms.
Examples of two polymers of this formula are Y-O-CF2-OY and Y-O-CF-(CF3)-OY wherein Y is the same.
This invention further pertains to a method of making perhalogenated formal, acetal, ketal and orthocarbonate compounds and perfluoropolyether and perhalogenated chlorofluoropolyether polymers thereof. The compounds are made by fluorination of acetal, ketal, formal or orthocarbonate hydrocarbon precursors.
The reaction of a diol with either an aldehyde, acetal, ketal or trialkyl orthoesters can be used to give a polyether if the starting materials and reaction conditions are carefully chosen. For example, if an aldehyde such as formaldehyde, acetaldehyde or butyraldehyde is reacted with a diol, a linear polyether can be made. Such a reaction is shown in Equation (1) below:

HO(CH2)nOH + RCHO ~ [(CH2)nOCHO]x + H20 (l) R

,' ~ , . . .

.. .
.

~; ~ iO29 l Suitable dlols incl~de e~hylene ~lycol, dlethylene glycol, tri~thylene glycol, te~rsethylene glycol, other higher polye~hylene glycols, propyle~e ~lycol, dipropylene ~lycol, trlpropylene glycol, ~,2-di-methyl 1,3-prop~nediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hex~nediol, 1,7-heptanediol, .
1,8-oc~anediol, l,9-nonanediol, and l,lO-decanediol.
Suitable aldehydes include formsldehyde, para-formaldehyde, l~3,5-trioxane, acetaldehyde and its ~rimer~ b~tyraldehyde ~nd its tri~er, pentanal, he~anal, 2-ethyl butanal, chloroacetal~e~yde, dichloroacetaldehyde and trichloroacetaldehyde, An alternative means of preparing the same polymer involves the reactlon of an acet~l wlth a diol. Tbe synthesi~ involve~ the inieial prepara-tion of an ~cetal by react~on of an alcohol with the aldehyd~ ~s shown ln Equ~tion (2~ below:

RCHO + 2R'OH ~ ~'0)2C(R)~ ~ H20 (2~

The acetal interchange is followed by a smoo~hly reversible react~on in acid media givins rise to the polyacetal. This resctlon i5 ~iven in Equation (3) below:

(R'~)~C(R)H ~ HO(CH2)nO~ ~

HOt(CH2)noC(R)~o~x~ ~ 2~'oH ~3) Suitable ~ce~sls lnclude the dietbyl, d~propyl, dibutyl, dipentyl and diphenyl acet~lx of all o~ the prevlously mentioned aldehyde~, d~; 3 1 ~ 2 9 4 A well kno~n reaction whlch i~ pArticularly well suited for preparing copoly~e~s o~ ~cetaldehyde involve-~ t~e react~o~ of divinyl ethe~s ~it~ diols.
Fo~ example, ethylene gl~col ~ivinyl et~er will react w~th ethylene ~lycol in the pre~ence of ~ at -10~~ to glve a l:l copolymer of ~thylene gly~ol and aceta}dehyde. ~imila~ly. the divinyl ether of l/S-pentanediol wlll react with l,S-pentanediol to give a copolymer of pentanedlol and aceta~dehyde:

CH2-cHc)cH2cH2~H2C~12cH20cH~cH2 + ~CH 2CX2CH2CH2C~20H

H
[CH2C~12C~2cH2~H20cH~~n F2~N2 - .~ [CF2CF2~F2c~2cF2OqHo]n Terpolymers can be prep~red by rea~tln~ a div~nyl ether of one d~ol with ~ dlol of a d~fferen~
~tructure. For example, the divinyl ether of ethyle~e ~lycol will react with 1,3-propanediol to yieLd a polye~her ~fter fluorin~tion having the followin~ structure;

~OCF2CF20(~0CF~CF2CF2 In 1029~

The divinyl ethers are conveniently for~ed by reactlng a dihydroxyl ter~nated compound with acetylene a~ 160~C ~n the presence of KOH as shown below in Equatlon (5).

HOCH2CH2OH + H GCH ~ CH2-CHOC~CH2OCH~CH2 (~H2- CHOCH~C~120CH=~C~12 + HOCH~CH2CH20H ~

~OCH2C~2Ol~Oc~2cH2cH2ln ~2/~2 ~- ~ E~CF2cF2~pFo~2cF2cF2~n (g) A variety of aldehydes can be polymerized snd fluor~nated to give perfluoropolyethers that ha~e uni~ue ~nd often ~seful properrles. For example, chloroace~sldehyde can be polymerized ~nd fluori-nated to ~i~e perfluoropolychloroacetaldehyde.
Similarly, d~c~loroacetaldehyte and trichlo~o-acetaldehyde can be poly~er~zed and ~luorinated to ~ive the perfl~orocarbon analog of the polyethers.
Chloro~luoroe~hers such as these are po~entially useful no~ mab~e a~rcraft hydraulic fluids.
Their relatively ~igh oxidatl~e st~bil1ty and low compressibility ~ake the~ attract~ve candidates.
Other ald~hydes ~uch as acetaldehyde, trifluoro-acet~ldehyde and propanal c~n be pol~erlzed ~nd fluorlnated to give stable poly~ers, -~34029 1 ~ etsls undergo a fac~le rever~ible motathes~s reaction with alcohol~ to ~i~e polyketals ~s shown below in Equation ~4):

) 2 C ( E~ ) R ~ HO ( C H 2 ) nOH

HO[(CH2)nOC(R)(~'')O]XH +2R~oH (6) The list of u~eful k~tal~ w~uld include 2,2-dlme-thoxypropane, 2,2~ ethoxybutane, 2,2-dimethoxy-pentane, 2,2-dimethoxyhexane, 3,3-dimethoxypentane, 3,3-dimethoxyhexane ag well a5 ~he diethoxy, dipropoxy, dib~toxy ~nd diphenoxy a~alo~ues o~ the prev~ou~ly mentioned ke~al~.
The direct reac~ion of a ketone with an alcohol, a reaction analogous to the reaction of an aldehy~e with an ~lcohol, gener~lly wor~ only for several isolated ketones. For ~his rea~on, the ketal is normally used.
The react~on of a ~ri~lkyl or triaryl ortho-ester with ~lcoholg gives form~tes according to t~8 reaction prex~nted in Formul~ ~5):

OH
(l~2)n (RO)3C~ t 3~0~G~)nO~ ~ H~-O(CH2)nOH ~ 3R~ (7) o 2~n OH

.... .. .

1~ 102~4 Use~~1 orthoe~ters include tri~ethylorthoformate~
~rieth~lorthoformste, trlpropylorthoformate, t~i-butylorthoformate, ~riphenylor~hofoYm~te, trimethyl orthoace~e, ~riet~ylor~hoacetate, erlpropylortho-~cetate, tributylorthoacetste, triphenylortho-acetate, tr~e~ylorthopropionate, triethylortho-prop~onate, trlpropylortho~ropionate, ~rlbutylortho-~ropionate, criphenylor~hopropionate, trimethyl-orthobuty~ate, txiethylortho~tyrate, tr~propyl-orthobut~rate, tributylorthobutyrate and ~riphenyl-o~thobutyrat~.
It should be clear from ~he preceeting discus-sions that a wlde variety of linear 8s well ~s hi~hly branched polyethers can be madé using ~hese interc~an~e reactions. ~y care~ully c~oosin~ the app~opriate d~ol and aldehyde ~t is possi~}e ~o prepare cyclic ~cetals which can often be poly-merized to g~ve polyether~. For exa~ple/ for~alde-hyde reacts with diethylene glycol ~o give 1, 3, 6 -trioxoc~ne w~ich oan be poly~erized to ~ive linear polyacetals as ~hown in ~o~mula (S) below:

(C~2~)3 + ~OcH~cH20c~2cH20H ~ CH2CH20CH2CH2GC~20 H ~ [CH2CH20GH2cH2oc~o~ ~8) S~ilar~, the cyclic product~ for~ed by the re-action of tri~ethylene ~lycol wit~ dibutyl formal and the reaction of hexamethylene ~lycol with propionaldehyde polymerize In the presence of an acid to gi~en l~near polyme~s ~s descr~bed in U.S.
Pa~ent N~. 2,071,252. In general, if the glycol is C

.

~ 3 1029~

1,4-butanediol or higher a linear polymer is formed whereas glycols having fewer carbons generally form rings. If the glycol used is a polyether glycol, such as diethylene glycol or triethylene glycol, the linear polymer represents a thermodynamically more stable structure. However, it is often possible to convert the linear polyether to the cyclic ether by vacuum pyrolysis.
The invention also pertains to "single compound" formals, acetals and ketals and a method of making formals, acetals and ketals, including polymeric compounds of the above-formulae and single compounds of Formula III:
~Rl Y-o-C-O-Y' III

wherein Y and Y' are the same or different and are selected from the group consisting of perfluoro-alkane, perfluoroalkylether and perfluoroalkylpolyether wherein fluorine may be substituted with one or more halogen groups other than fluorine; wherein R1 and R2 are the same of different and are selected from the group consisting of -F, -Cl, -CF2Cl, -CFCl2, - CCl3, perfluoroalkyl of one to ten carbons; wherein fluorine may be substituted with one or more halogen groups other than fluorine and wherein the perfluoroalkyl group may contain one or more ether oxygens. The perfluoroalkyl polyether which is Y and Y' may be atactic, isotactic or a block copolymer having 1 to 50 carbon atoms.
As an example, a monohydridic alcohol will react with an aldehyde, acetal or divinyl ether to give a new acetal.
2ROH+HCR'O RO-CHR'-OR (9) ~3102~

~ipropylene glycol bu~yl et~er, tripropylene glycol ~ethyl ether, ~rlpropylene gl~col ethyl e~her and tripropylene ~lycol butyl ether, Low moleculAr welght, unimolécular perfluoro-polyether fluids find numerous applicat~on in che eleccronics lndu~try. Fluoroc~rbon fluids arc usef~l ~s coolants and lnsulator~ in high-voltage electronic equipment, as i~mersion ~ediu~ for leak testing, as heat transfex agents for v~por phase solderin~, as fluids for dlrect cooling of elec-tron~c de~ices and as thermal s~ock fluids.
Fluorinated polyether acetal~, such as the ones descr~bed hereln ~ay al-~o find uses ~s fluoroc~rbon blood substitutes, ~ on~er~ion of the hydrocarbon polyether ~o ~
perfluoropolyether can be acco~plished by reactlng the polyethe~ with elemental fluorine. Because o~
the reactive nsture of elemental ~luorlnc, it ~s p~eferably to dilute the fluor~ne wi~h an inert gss such as nltrogen or helium. Typically, the fluorine is diluted with ni~rogen and as highex de~rees of fluorlnation are achleved, the concentr~tio~ of fluorlne is usually increased. ~ue to the extreme exothermicity of the reactlon, t~e fluorina~ion ~u~t be carried out slowly unless provisions have been ~a~e ~or rapidly xemoving the heat of reaction.
Submersion of che reac~or in a cooled llquid bath is usually adequate for achievlng commerclally acceptable rates o~ reaction.
Fluorine ~as i~ the preferred fluorinating a~en~ and is comm~rciall~ availsble at ~ufficiently .. . ...
. .

-~ 3 '~ O 2 9 4 1g -2ROHf~R' '0~2CR'H ~ RO-CHR'-OR ~10) 2ROH+CH2 CHoR~oc~l-c~2~RocH(cH3)oR~ocH(c}~3)oR (11 The reaction of an alcohol with a ketal will result in an interchange reactlon glven rise to a ketal.

~ROH~(R''0~2CR'R'''-~ RO-CR'R'''-OR (12) A monohydxidic alcohol will ~eact ~lth ~n ort~oester to give another or~hoester.

3R~H+~R'0)3CH -~(RO)3CH (13) Low molecul~r we~ght uni~olecular pol~ethers can be made by re~ctlng any of the previously mentioned aldehyde~, ~cetals, ketals, or or~hoesters with ~ monhydridic alcohol ~uch ~s ~ethoxyethanol, ethoxyethanol, butoxyethanol, diethylene glycol methyl ether, d~ethylene ~lyco~ ethyl ether, d~-ethylene glycol bu~yl ether, triethylene gl~col methy~ ether t triethylene ~lycol cthyl ether, tri-ethylene glycol butyl ether, tetr~ethylene glycol-methyl ~the~, tet~aethylene glycol ethyl ether, cetr~ethylene ~lycol bu~yl ether, pentaethylene glycol methyl ether, pentaethylene glycol ethyl e~hex, pentaet~ylene glycol ~utyl ethe~, propylene ~lycol methyl ether, propylene glycol e~hyl ether, propylene glycoL butyl ether, d~ propylene glycol me~hyl ether, dipropylene glycol ethyl ether, ~ J ~029~

high purity levels and at an acceptable cost. The fluorination reaction is generally carried out at a temperature between -40 and +150~C, preferably between -10 and +50~C. It can be carried out in a reactor containing an ultraviolet radiation source or in the dark. Using the preferred temperature range, it is not necessary to have an ultraviolet light source since the fluorine is sufficiently reactive. If an ultraviolet light source is used, however, a wavelength between 250 and 350 nm is preferred. When the reactor is irradiated with an external light source, a transparent window is needed which does not react with either fluorine or hydrogen fluoride. A quartz lens coated with a thin film of fluorinated ethylene-propylene copolymer works well.
The fluorination reaction can be carried out in a variety of ways. The polyether can be coated on sodium fluoride powder to give a free-flowing powder which can be fluorinated in either a stationary tube, in a rotating drum-type reactor, or in a fluidized bed. See U.S. Patent No. 4,755,567 and U.S.
Patent No. 4,859,747, issued August 22, 1989.
Alternatively, the polyether, if soluble, can be dissolved in a solvent inert to fluorine and can be fluorinated while in solution using a liquid phase fluorination reactor. See Canadian Patent Application Serial No. 613,091, entitled "Liquid Phase Fluorination", . ... : . . ....... . . . .

13~029~

by Thomas R. Bierschenk, Timothy Juhlke, Hajimu Kawa and Richard J. Lagow, filed September 28, 1989. A typical laboratory-size reactor for example, has a volume of about 10 liters and contains approximately 2 to 8 liters of a suitable solvent. Perhalogenated chlorofluorocarbons are typically used as the fluorine-inert fluorination medium. However, perfluorocarbons, such as Fluorinert~
FC75 [3M Corporation; mixture of perfluoro(2-butyltetra-hydrofuran) and perfluoro(2-n-propyltetrahydropyran)] and perhalogenated chlorofluoropolyethers may also be used as the liquid phase fluorination medium. One preferred fluorination medium is 1,1,2-trichlorotrifluoroethane since it does not react appreciably with fluorine when the preferred temperature range is used (above the melting point of the material and below the temperature at which the fluorine reacts with it). Other fluorinated solvents can be used, such as perfluoroamines, perfluoroalkanes, low molecular weight polyethers, etc.
During a typical reaction, the polyether is fed into the reactor at a rate of 10 to 60 grams per hour. Fluorine gas is delivered to the vigorously stirred reactor at a rate sufficient to react with all of the organic feed plus an additional 5 to 10 percent. Typically the fluorine gas is diluted with an inert gas such as nitrogen. This is of . ~ , ..... .. .

1~40294 particular importance if a liquid fluorination medium such as 1~lr2-trichlorotrifluoroethane is used. It is imperative to keep the fluorine concentration low so that the liquid fluorination medium and fluorine in the vapor space do not form a flammable mixture. The flammability limits of various solvents in fluorine gas can be determined by spark testing. In a typical reaction, a fluorine concentration of 10 to 40% works well. If operating properly, the fluorine concentration in the exit gas will be between 2 and 4%.
Fluorination can be carried out either in a batch mode where all of the polyether is dissolved in a solvent prior to fluorination or in a continuous mode where the polyether is continuously being pumped into the solvent as fluorine is being bubbled through the solution. Generally speaking, the continuous operation gives a preferred yield, better product quality and improved rates.
If the polyether is insoluble in the liquid fluorination medium it can still be fluorinated in high yield as an emulsion in the liquid phase reactor. An emulsified solution of the polyether and the fluorine-inert liquid fluorination medium can either be pumped into the reactor or the reactant can be emulsified in the reactor with the fluorination medium prior to the reaction.
An alternative method for fluorinating poly-ethers which are insoluble in the liquid fluorination medium involves adding a solvent to the polyether which allows limited solubility of , polyether in the liquid fluorination medium. For clarity, 1,1,2-trichlorotrifluoroethane has been selected as the liquid fluorination medium; however, other highly fluorinated solvents can also be used.
Typically, a mixture containing one part polyether, one part solvent and one part 1,1,2-trichlorotri-fluoroethane will give a homogeneous solution. A solvent is selected which readily dissolves the polyether. Often it is possible to choose a solvent which will consume little, if any, of the fluorine gas. Trifluoroacetic anhydride, trifluoroacetic acid, chloroform, ~ 2-trichloroethylene and 1,1,2-trichloroethane work especially well and have high solvating power.
The polyether/solvent/1,1,2-trichlorotri-fluoroethane solution is metered into a vigorously stirred fluorination reactor. As the polyether solution contacts the 1,1,2-trichlorotrifluoroethane in the reactor, an emulsion is formed. The polyether droplets in the solution are in most cases sufficiently small and react quickly with the fluorine gas with negligible side reactions.
When carrying out the reaction in a liquid fluorination medium, a hydrogen fluoride scavenger such as sodium fluoride or potassium fluoride may or may not be present in the solution to scavenge the by-product hydrogen fluoride. However, the prefer-red mode of carrying out the fluorination reaction is with a sufficient quantity of sodium fluoride being present to complex with all of the hydrogen fluoride formed. When fluorinating ethers in the . . .

2 g ~1 presence of sodium fluoride, improved yields are obtained while chain cleavage and rearrangements are minimized. See U.S. Patent No. 4,755,567.
Products produced using the methods just described usually have a residual hydrogen content of 0.001% or less. In order to obtain a fluid which is essentially free of residual hydrogen and void of any reactive terminal groups such as acyl fluoride groups resulting from chain degradation reactions, a final fluorination near 175~C with 30% fluorine for several hours works well.
The following examples will further illustrate the invention, but are not to be construed as limiting its scope.

Example 1 A mixture of 1060 g diethylene glycol (10 mol), 210 g paraformaldehyde (7 mol), 500 ml benzene and 10 g acidic ion exchange resin was refluxed for 6 hours in a 2 liter flask equipped with a water separator and a reflux condenser. The solution was filtered to remove the acid catalyst and the benzene was removed by distillation. Upon removal of all of the benzene, several drops of sulfuric acid were added to the polymer and the temperature was raised to approximately 140~C. The entire contents of the flask were distilled at 160~C with a reduced pres-sure (25 mm). Redistillation of the high boiling fraction gave 463 grams of 1,3,6-trioxocane (78%
conversion).

1~40294 Polymerization of 450 g of 1,3,6-tr~oxocans was ca~ried out ~t room temperature In 1 liter dry meth~lene chLoridc using 0.04 ml of trifluoromet~ane sulfonic ~cld ~s a catalyst. T~e poly~eri~ation was complete in 24 hours at which time 1 g of sodiu~
methoxide disso~ved ~n 50 ml of dry methanol was added to neutralize the acid catalyst. 3600 ~
sodium fluoride powder wa~ added to the poly~er along wi~h sn additional 1 liter of methylene ehloride, T~e mi~ture was stlrred, t~e methylene chloride w~s allowed to evaporate and tbe re~aining solid~ were ground to a powder. The polymer-coated sodium fl~or~de was placed in a 20 liter rot~ting drum reactor and dried under a stream of inert ~as te.g., nitrogen) for a perlod of 12 hours, The mlxture was t~en exposed to 500 cc fluorine diluted with ~ literg of nitrogen for approximately 30 hours at 25~C. Next, the nltro~en flow was red~ced to 1 llter/min and the re~ctiOn w~s a~lowed to continue for an additional 12 hours after which ti~e the reactor was slowly warmed to 70~C o~er a 6 hour period. Trea~ment with pure fluorine for several hours at 70~C ~ave a product which contained very few hydrogen a~oms. Extraction of the reaceion product wlth 5 liters of 1,1, 2 - trichlorotrlfluoro-ethane ga~e 386 grams of fluid (34~). Washing of the solids wit~ 100 liter~ of ~ater resulted in the isol~tion of 430 ~rams of an elasto~eric solid (38 yield). The crude ~luid w~s treated with 30~
fluorine at Z60~C for 12 hours ~o ~emove t~e last rem~inin~ hydxogens. The fluid was distilled to gi~e the followin~ fractions:

~3~0294 Klnematic b.p. Weight Vlsoosity (cst.
ran~ f~ac~on ~ of ~otal 20~C 80~C
<200~C ~t 100 mm 120 31 3.2 1.07 ~200~C at lO0 mm12~ 33 11.8 2.~3 C245~C ~t 10 mm >~45~C at l~ ~m 62 16 38.9 7.06 c288~C at 0.~5 mm ~288~C at 0.05 ~m 39 10 8~.3 13.1 ~370~C a~ 0.05 mm ~370~C at 0.05 mm 39 10 290.3 3g.5 The l F data and elemental analy~is were consistent with the structu~e:

~CF2CF20 CF2CF20 CF20]n Example 2 In this example the fluid prepared in Example 1 w~s prepared usin~ an alternate method whlch was better sui~ed for preparing fluid-~ while the method described in Example 1 yLelds a con~lderable amount of polymeric solids.
Into a l liter stlrred flask equipped with ~
wa~er ~eparator were placed 500 g d~ethylene ~lycol (4.7 mol), ~0 g diethylene glycol ~ethyl ether (10.75 mol), 225 g paraformaldehyde ~7,5 ~ol), 150 ml toluene and 5 g ion excha~ge resln (H fo~m).
The mixture wa~ refluxed for several hours to remove the water formed dur~ng the reaction. The solu~ion was ~irs~ filtered to remove the ion exchange resin, -- ~ 3~029~

then distllled to 150~C ac 0.05 mm/Hg to remove the tol~ene and other lights. A nearly quantltatlve yie}d of polymer having an a~erage molecular welght of 1500 wa~ obtained.
320 g of polymer. mixed wlth 170 g chloroform and 300 g 1,1,2-trichlorotrifluoroethsns w~re slowly pumped over ~ 23 hour period into a 15 llter stirred fluorination reactor containlng 6 llters of 1,1,2-trichlorotrifluoroethane ~nd 1300 g of sodium fluorlde powder. 20~ fluor~ne was bubbled t~rough the liquid fluorinstion medlum at a rate 15~ hlgher than that required to theoretically replace all of the ~ydrogen on ~he hydrocarbon being pumped into the reactor. The reactor temperature was maintaine~
between 0 and +lO-C throughout the reaction.
Follo~ing the reaction, the reactOr contents were ~iltered and the liquld fluorination med~um (l, l, 2-triohlorotrifluoroethan~) was removed from the flltrAte Vi8 an at~ospheric distil}ation to 120nC to ~ive 53~ g of crude fluid (66~), Fl~orlnation of the ~luid at 260~C gave a clear7 colorless fluid whloh ~as shown by element~l analysi~ and 19F NMR to have t~e ~ollowin~ structure:

[C~2~F20CF2CF20CF20]n Example 3 100 g triethylene glycol (0.67 mol), 28.5 g para~ormaldehyde (0.95 ~ol), 100 ~l benzene and 1 g lon exchange resin (H form) were placed in a 500 ml stirred ~ k eq~ipped ~ith a water xepara~or and a r~flux con~enser. The solution wa~ allowed to reflux ~or ~ hour~ while t~e water wa~ continuou~ly removed. Upon removal o~ the w~er, the 801ution was filtered ~o remove the acid cat~ly~t. At-mosph~ric distlllatlon of the flltrate followed by ~educed pressure dist~llation (100 m~ Hg) to 120-C
was u~ed to remove th~ benzene solvent ~s well ~s any light~ presen~.
Twenty grams of the viscou~ poly~er were mixed wlth approximately 100 ml of ~ethylene chlorlde and 120 ~ sodium ~luoride powder (200 ~esh). The resulting paste was dried ln ~ ~acuum oven at 60~C
for sever~l hour~ prior to grlndlng eO ~ coarse powder (~ppro~imately 30 ~esh), The powder wa~
placed in a 1 lltor rot~ting brass reac~or a~d wa~
puxged wlth 200 cc of dry nitrogen for ~everal ~ours prior to the fluorin~tion. The ~sactor was cooled to 0~C, the nitro~en flow wax reduced to 150 ~c/mln and the fluorine flow was set at ~0 cc~mln. ~hese conditions were mainta~ned for ~pproxl~tely 30 hours af~er whlch time the nitrogen flow was reduced to 100 ce/min and the ~eactor was ~llowed to slowly warm to 45~C ovsr a 4 hour period, Next, the nitrogen flow was turn~d off and the reac~or wa~
slowly warme~ to 70~C over a 3 hour period. Upo~
heatin~ to 70~C, the polym~r was exposed to pure flouri~e for an addi~lonRl hour. Extraction of the ~odium fluorlde~polymer mlxtu~e with approxima~ely 1 llter of 1,1,2-trichlo~orrlfluoroethane g~v~ 23 g of fluid (45~ yield) h~vin~ the following struc~ure which has been confirmed spectroscopic~lly:

l~ 1029~

~ CF2CF2~C~2~2~CF 2CF2~CF2~ }

Example 4 ~ 00 ~ butoxyethoxyethanol (2.5 mol), 4~ g paraformalde~yde ~1.6 mol), 300 ml benzens and 5 g io~ exchan~e resin ~acid form) w~re placed in a 1 liter ~t~rred flask. A water separstor attached to a reflux condenssr wa-~ used to collec~ the water produced ~s the ~lcohol ~nd aldehyde reacted. After approxim~tely 6 hours, the ~e~ction w~s compl~te and the solutlon wa~ filtered to remove the resin.
V~cuum dis~llatlon of the so~ut~on to 120~C gAve 414 g of a product (~g% yield) ~hich w~s e~senti~lly ~ree of benzene and unreacted start~n~ materials.
The hydrocarbon product was fluarinated in a 22 liter stirred tank reactor w~ic~ co~ta~ned 6 l$ters of 1,1,2-tric~lorotrifluoroetha~e and 13~0 g sod$um fluoride p~wde~. A gas dispersion tube in the botto~ of the reactor provided an inlet for the fluorlne and nitroge~ gasses. 275 gram~ of the hydrocarbon reactant was d~luted w$th 1,1,2-tri-chlorotrifluoroeth~ne, in a separ~te ~es~el, to ~ive a total volu~e of 700 ml. This solut$on was metered ~nto the ~luorinatlon ~eactor over a 20 hour period.
The reactor teDper~ture was maintained at 0~C wlth external cooling throughout th~ react$on whlle the fluorine flow was ~et at a levcl lO~ highsr than th~ requlred ~o theoretically replace all of the hydrogens on the materiAl ent~r~ng ~he reactor.
Upon completion of the reactlon, the fluor~ne ~as -turne~ off, the re~ctor was re~oved from the low -~ 3-~102~4 temper~ure ~at~ and purged for 30 min w~th ni~rogen ~2 liter~/~in) ~o remove the unreacted fluorine.
Fil~ration of the reaction product followed by distlllation to re~ove ~he 1,1,2-tric~lorotrifluoro-ethane gave ~4~ g of a highly iluorlnated fluid ~0 yield). Treat~ent of the fluid a~ 260- C with 304 fluorine ~or several hours gave a perf~orinated fluid having essentlally the following ~truc~ure:

3 2 2 2 F2 2 2 2 2 CF2C~20cF2c~2ocF2c~2 The ele~ental analy~l~ was COnsistent with the formula:
C17F36~6 ' b.p. 226.5~~
~ F NMR ~ ppm ~s CFC13):
-89.0, -90.7: CF2CF20; -51-8: CF20 -81-8, -83.7.
-126.7: CF3CF~F2CF20.

Example S
A mixture of 400 g triethylene g~ycol monoethyl ether ~2.2 mol), 48 ~ par~formalde~yde (1.6 mol), 150 ml tol~ene and 10 ~ of a~ acid ion exchange resin was reflu~ed for ~ hours in ~ 1 liter flask equipped with a water ~epara~or and reflux con-denser. Filtra~ion o~ the product followed by dlstill~t~on gave a qusntitative yield of the desired product.
Fluorination of 201 ~ of the ma~erial in a s~irred liquid ~luorination resctor containing . ~ . , liters of 1,1,2-trichlorotrifluoroet~ane and 1055 sodium fluoride ga~e 401 g fluid ln an 18 hour reaotion at 0~C. Distillation of the ~rude product ~xture gave 35g g of the perfl~orinated fluid:

CF3cF2ocF2cF2ocF2cF~ocF2cF2ocF2ocF2c;F2ocF2cF2ocF2 -CF20~F2CF3 C17~8F3~
b.p, 217~C
9F ~ISR (iS. ppm vs CFC13):
- 51. 7: CF20; - 87 . 3, - gO . 7: CF3CF2; - 88, 7 CF2CF20 .

Ex a~np 1 e 6 Into a l liter flask were placed 600 g tri-ethylene glycol butyl eth~r (2.91 mol), 74 g para-formaldehyde (2.46 mol), lS0 ml benzene and 10 g of a~ acid~c ion ex~hange ~e~ln. The mixture w~s reflu~ed for 5 hours as water was remo~ed a~ ~he water/ benzene a~otrope. Filtratlon of the product and re~oval of t~e benzene by distill~tion g~ve a 90~ yield of rhe polyethsr. 2S9 gram-~ of the produc~ wa~ diluted wlth 400 ml 1,1,2-trlchlorot~i-fluoroethane and W8S slowly ~etered in~o a 10~~
reac~or conta~ni~ 5.7 liters of 1,1,2-trichloro-trifluoroethane and 1200 g sodiu~ fluoride powder.
A fluorocarbon fluld (660 g, 88.7% yield) wa~
obt~ined follo~lng filt~atlon and removal of ~he 1,1,2-trichlorot~ifluoroethane. Fluorlnatlon of the fluid at 220~~ wlth 30~ fluorine ~or 12 hours followed by d~stilla~ion gave the ~ollowln~ fluid in 60~ yield:

~ ~!10294 CF3cF2~F~C~2OCF2cF20cF2cF2 2 2~~2~CF2 F2 2~ 2 OCF2C~2QCF2CF2 CF~CF3 b.p. 262~C
F NMR (6 ppm ~s CFC13):
-8~.7, -90.5:CF2CF20; -51.7;CF20; -81.6, -8~.4, -126.5:CF3CFz~F2CF20.

Example 7 Inco a ~tirr~d 1 liter flask equipped with a water separato~ were charged 350 g tetrae~hylene glyco} butyl ether ~1.40 mol), 35 g paraformalde~yde (1.18 mol), 200 ml benzene and 10 g ion exchan~e resin. ~he mixture ~ax refluxed untll the water produc~ion ceased. ~iltration of the product followed by removal of tha li~hts via a vacuum dis~ tion to 140VC ~ave 343 g of a llght yellow fluid, ~ 306 g sample of ~he fluid was diluted w~th 450 ml of 1,1,2-trlchlorotrifluoroethan~ and slo~ly p~ped ~nto a -6~C resctor over ~ 23 hour period.
The reactor contslned 1450 g o~ sodium fluoride powder to react with ~he hydrogen fluorlde for~ed during t~e reaction along wit~ 6 l~ters of 1,1,2-trichlorotr~fl~oroethane. Filtration of the pro~uot followed by dlsrillation gav~ 736 g of fluid.
Treat~ent of the fluid at 250-C wit~ 30~
fluorlne gave a clelr, odorlas~ fluid which upon distillation gave a 52% yield of a material having the following structure:

-? 3 1~29~

3 2 F2CF2~CF2 F2 2 2 2 20cF2cF2ocF2ocE~2cF2 O C F 2 ~ F 2ocF2cF2oçF2~2ocF2cF2 2 3 b.p. 29~.7~C
F NMR (~ ppm v~ CFC13):
-51.B:CF20; -88,8, -90.6:CF~CF2~; -8~,7, -83.6, -12~.7:CF3CF2CF2GF2O, Example 8 400 8 tet$ae~hylene glycol (2.0~ mol), 109 g paraformaldehyde ~3.62 mol), 17 ~ triethylene glycol methyl ether {0.103 ~ol), 150 ~1 benzene and 5 g ion exchange resin were ~llowed to react in a 1 liter flask containing a water separator, After 6 hours, ~he contents o~ the flask were filtered and t~e lights were removed via ~ vacuum filtratlon. A 265 g ~ample of the polymer was mixed with 160 g chloroform and 2~5 g 1,1,2-trichlorot~ifluoroethane, The polymerlc sol~tion was metered, over a 22 hour period, ~nto a stirred 10 liter fluorinatlon reactcr which contdined 1150 B sodium fluoride powder and 4.5 lite~s of 1,1,2-trichlorotrif}uoroethane. The reactor was malnta~ned fft 7~C while 20S fluorine (diluted with nitrogen) was metered into the reactor at a r~te su~flci~nt to ~eact with all of the organlc enterin~ the reactor. Upon completion of the reaction, the solut~on was filtered and the li~uid fl~orination ~edium was removed via a d~s-tillation yielding 422 g (62~ yield) of a clearl ~tab}e fluld ~he product was fractionated into ~ ~ ~0294 ~ree ~amples, one which boiled b~low 200~ C at 0 . OS
m~ Hg (40%), ~ second which boiled between 200 and 300~C at 0.05 mm ~3596) and a third ha~in~ a ~oil~ng point above 300~C at O.OS rum Hg (259~). The inter-mediate fracti on had a visco~ity of 33 .1 cst. at 20~, 6 . 3 c:st . at 80~ and 2 .13 cst, ~t lSû~C . The pour point was -7~C. The analy~l~ wax con~i~tenc with the formula:

1 CF~F20CF2CF20CF2CF20CF2cF2OcF20 3 n F NMR ~ ~ ppm v~ CFCl 3 ) - 51 . ~: CF20 - 5 6 . 0: CF30; - 88 . 8, - 90, 6: CF2GF20 .
Anal. Calcd. for GgF1~05: 2~ . 4, C; 6~ . 5 ~ F .
~ound. 21.0, ~; 65.1, F.

Example 9 Dlpropylene glycol methyl ~ther ~300 g, 2.04 mol~, 60.8 g paraformaldehyde (2.03 ~ol), lO0 ml toluene and S g o~ an acid catalyst were mixed in a st~ r~d 1 liter fla~k. After refluxing for 12 hours, the solution was filtered and dist~lled to give 203 g of a fluid whlch bolled at 140~C at 0.05 n~m Hg. The fluld (200 g) was r~ixed wich 300 ml 1,1,2-~ichlorotr~fluoroeth~ne and g~0 g sodium ~luorlde powder, The reaet~on ~7as compl~te ~L 18 hours after whlch tl~e the solu~ion was flltered and dls'c~ lled to ~ive 405 g of a clear 1 iquid having the followlng ~tructure (71~ yi~ld) ~3 102~4 ' CF30C3F60C3F60CF20G3F60C3F60C~3 The fluid contains CF(CF3)CF20CF(CF3)CF20, ~F(~F3)CF20CF2CF~CF3)0 and CF2CF(CF3)0CF(CF~)CF20 l~nk~ge~. The structure was conflrmed by F ~MR
and el emeRtal analysi~:
1~
F NMR (~ ppm vs CFCl3) :-47.~:CF3O;-54,0:CF20;
-~O.O:CFtCF3)CF20;-~2 to-87:CF(CF3)CF20;-140 to-150:
CF(C~3) CF20 .

Example 10 A mixture of 300 g tripropylene ~lycol methyl e~her (6.46 mol), 33.7 g parafor~aldehyde ~1.12 mol), 150 ml benzene and 3 g ion exchange re~in was refluxed for 6 hours in a 1 liter flask equipped with a water sepa~ator and reflux conde~sc~.
Filtration of the product followed by vacuu~ dis-tillation of the 11ghts ~ave 16~ g of a product with a boiling point abo~e l50~C at 0.05 mm Hg.
Fluorinat~on of 145 g of the ~aterial, dis-solved in 4S0 m1 1,1,2-trichlorotr~fl~oroetha~e , in a stirred fluorlnation r~actor containing 6 lit~rs of 1,1,2-trichlorotrlfluoro~thAne ~nd 700 g o~
sodium f~uoride gave 244 g of a fluorocarbon product in a 20 hour reactlon at -3~C. Dist~llation of the prod~ct gave 180 g of the perfluorinated fluid:

CF30~FCF20)3C~2(0lFcF2)ocF3 where the ~exafluoropropylene oxide units are attached randomly ln a head to head, head to tail and tall to tall fashion.

F ~M~ (~ ppm ~-~ CFC13):-47.3,-56.0:CF30;--54.0:CF20; -80,0 CF~CF3)C~20;~83,0,--8$.3:CF(CF3~CF20;-145.3, -l46~o:cF(cF3)cF

b.p. 2~0.0~C, Example ll A mixture of 400 g dipropylene glycol ~3.0 mol), 358 g paraformaldehyde (12 mol), 150 ml tolue~e ~nd lO g ion exchange ~e~in was refluxed for 5 hour~ in ~ ~tirred 1 liter fla~k equipped wi~h a water separator. The ion exch~nge resin was removed p~io~ to distillation of the mi~ture to 150~C under a full v~cuum to ~emove a~y low molecular ~el~t polyme~. Approximately 200 g of polymer remalned in the fl~sk which was sho~n by ~el permeation chro~atography to h~e an average molecular wei~ht of appro~imately 30~.
The polymer (~80 g~ was mixed wi~h 340 ml 1,1,2-~ic~lorotrlfluoroeth~ne and was slowly pumped into a 15 liter stirred reactor over a 24 hour perio~. The reacto~, which contained 5.5 llte~s of 1,1,2-trichlorotri~luoroethane and 1220 8 sodium fluorlde powderl was ~aintained at lO~C throughout the react~on while 20~ fl~orine was bub~led throu~h the llq~id fl~orination medium ~t a rate just exceedin~ that req~lr~d to react with all of the ~, 1029 1 starting material being pumped into the reactor.
The reactor contents were filtered and distilled to give 587 g of fluld which was further tre~ted with 50~ fluorine ~t 270UC to give a fluld whlch was essent$ally free of hydrogen. The purl~ied pro~uct w~s fractionated into three samples. The first f~action boiled below 200~C at 0.05 m~ H~, the second distilled ove~ ~etween 200 and 300~C ~t 0.05 mm an~ the d~still~tion bottomg had a boiling po~nc ~bo~e 300~C at 0.05 mm ~g. The second fraction comprised approximately 20~ of the total fluid with the ~a~ority of the sa~ple h~ving ~ boil~ng point below 200~C at 0.05 m~.
The visco~ity of the secon~ fraction at 20~C
w~s 72.2 cst. (ASTM slope of 0.644). ~he pour point was -62-C.

F ~ilME~ (S ppm vq CFC13):-47.3,-49.3,~Sl.4:CF20;
-54 O, -5s~8;cF3o;-79~7:ocF(~;F3)cF2o;
- 84 . 7: OCF ( CF3 ) GF20; - 8 7 . 3: GF3CF20; -130 . 0 ~ F3CF20;
-140.3, -144.8, -146.0:0GF2CF~CF3)0, Anal. Calcd. fo~ CF30[CF2CF(~F3)0CF2CF~CF3)QGF20]n-CF2CF3; C, 2}.02; F, 67.02.
Found. C, 21.08; F, 67.08.

~xample 12 Using techni~ues similar to tho~e described in the previous examples~ 350 g 1,4 butanediol, 43 g n-propanol ~nd 200 g paraform~ldehyde were reacted in benzene to give a fluid which ~as treated with -85g acetlc anhyd~ide to give 325 g of a polymeric material ~aving a viscos~ty of 162 cst. at 30~C.
Fluorin~tion of 3~5 g o~ ~he fluid in ~ typical 40~C
fl~orination reactlo~ gavs 577 g of fluid of whi~h approximately 30~ boiled b~tween 200~ and 300~C at O.OS mm/Hg, F ~MR (~ pp~ vs CFC13):-51.7(f), -82.1(a), -85.4(d), -8~.5~c), -125.9(e) and -130.3(b) CF3cF2cF2~cF2c~2cF2cF2ocF2o]n CF2CF2CP3 a b c d ~ e d f c b a Exam~le_13 In~o ~ 1 liter stirred fla k were plac~d 350g 1,5 pentan~diol (3.4 ~ol), 23g n-b~tano} (0.3 mol), 175g paraform~ldehyde (5.8 mol) snd 200 ml benzene.
Upon refluxin~ the mixture for app~oxi~ately 3 hour~
wi~h an acld catalyst present, 390g of a poly~eric fl~id was obtained which h~d a vlscosi~y of 4S0 ost.
at lOO~F. Fluorination of 310g of the f~uid ~n a ~ypical fluor~nation reaction at 14~C ~ave 708g of fluid t80~ y~eld) of w~ich appro~mately 30% boiled between 200 and 300~C at 0.05 m~ Hg.

~F NMR (~ ppm v~ CFC13) -51.3(g), -55.7~c), -81.7(a), -8S,O(d), -122.3(f), -125,5(e) and -126.7(b) CF3C~2CF2CF20{CF2CF2CF~CF2CF20CF20~nCF2CF2CF2CF3 a b ~ c d e f e d ~ c b b 02~4 Example 14 Usin~ techniques s~mila~ to those ~escribed in the previous examples, 350~ 1,6-hexanediol (3.0 mol) 49.3~ n-pen~anol (0.S6 ~ol), 134g paraformaldehyde (4.46 mol) were re~cted in benzene ~o ~ive 425g of a polymeric material having a viscosity o f ~00 c~t. at 100~F. Fluorin~tion of ~2~g of the fluid ln a typical react~on at 10~C ~ave 6~8g o~ flu~d (71~
yiel~), of whic~ approximstely 30& boiled be~ween ~00 and 3~ at 0.05 mm H~, ~F NMR (~ ppm vs C~C13):-51.3(i), -5~.0~b), -81.7(a), -85,~ 85.3(e), -122.7(h), -123.0(c), -125.5(g) and -126.3(d) CF3CF2CF2CF2CF2o[cF2cF2cF2cF2cF2cF2ocF2o~ CF2CF C~
a b c d e f ~ h h g f i e d c b a Exa~ple 15 Into a 500 ml ila~k were placed 100 g diethylene ~lycol (O.g4 mol), S5.7 g acetaldehyde diethyl acetal (0.47 mol), 200 ~1 benzene and ~.5 g acidic ion exchan~e resin Attached ~o the flask was ~n apparatus designed to continuously ext~act t~e by-product ethanol from the refluxing benzene.
Af~er appro~i~ately ~ hours, the ~e~lux~n~ benzene ~ag essen~ially free of ethanol and the reaction was assumed to be complete. Filtration of the c~ude ~~ ~029~

re~ction product ga~e a solu~ion free of the ion exch~nge resin. Removal of the benzene was accom-plished using a ro~a~y evaporator ~7~~C bath with a n~trogen purge through the solution), 20 ~ra~s of the poly~erio product were mixed with lOO ml of methylene chloride and 12~ g sodium fluorlde powder. On drying the paste, 140 g of a ~ree-flowing powder was obtaln~d. U~ing the ~luor-ination procedures of E~ample 3, ~ 50~ yield of the following fluorinated fluid w~ obtained~

~CF2CF20CF2CF20CE~(CF3)0]n F NMR (~ ppm vs CFC13~:
-5~.0:C 30;-8~.3:0CF(~F3)0;-87.3:C~3CF2o;
-87~7:CF3~F20;-ss~7:0cF2cF20;-g6.3:0CF(CF3)0.

Example 16 Using the procedures detailed in the prevlou6 examplex, 400g tetraethylene glycol (2.06 mol) wa~
reacted with 243.5g acetaldehyde diethyl acetal (2.06 ~ol) in 250ml benzene to give 250g oi a polymeric fl~id upon refluxl~g for 6 hours. T~e polymeric liquid (350g) was coated on ~S55 ~ of sodium fluorlde and placed in a 22 liter rotating drum reactor. After p~rging fo~ sever~l hours, t~e reactor was cooled to -1~~C and the fluorine and nlt~o~en flow rates were set at 350 cc/~in and 2 liters/~in, respectiv~ly. After 2$ hours, the nitrogen flow w~s decreased to 1. 5 liter/min. After an ~ddltional 14 hours, the nitrogen flow ~as ~ ~10~9~

f~rther re~uc~d to 1 liter~min and the re~ctor was allowed to ~lowly warm to 35~C o~er a 4 hour period.
Upon reaching 35~C, the nitrogsn was turned off and t~e re~ctor was further warmed to 65~C pr~or to terminating the fluorine flow. An oll ~371g) w~s qxtractsd from the sodium fluo~ide with l,l,~-trichloro~rifluoroeth~ne which was determined to h~e t~e following structure:

)o]

9F N~ ppm vs CFC13) -S~.O:CF30;-86.7:0CF~CF3)0;-87.4:CF3CF20;
-BO.O:CF3CF2o;-88.7:0CF2CF20;-~6.7:oCF(C~3)0.

Exsmple 17 A mlxture of 600g d~ethylene glycol and 30g pot~ss~um hydroxide was heated to 160~C in a l liter flask. Acetylene gas w~ bu~bled throu~h the solu~ion ~s it was rapidly stirred, The reaction was stopped afte~ 48 hours and t~e product wa~
extr~cted with water s~veral times to remov~ any unreact~d diethylene ~lycol. The product, a d~vinyl ether of dlet~ylene glycol, was reco~ered by distill~tion (b.p. 196~C) in about an 80~ yield.
A 1 litsr flask cooled to -10~C was charged with 250g ~riethylene glycol ethyl ether ~nd a catalytic amount of methane sulfonic ~c~d. To th~s ~o~ut~on w~s a~ded slowly lOOg dlethylsne divinyl ether. Following t~e addition, the flask w~s slowly warmed to ~oom temperature ovsr a 3 hour period.

~029~

The product was dist~lled to 150~C at O.OS mm Hg to re~ove any unreacted starting materials.
The product from t~e above reaction can be f}uorlnated ~t ~O~C ~slng the procedures outl~ed in the prevlous l~quid phase fluorination exsmples to glve a perfluorlnated fl~id o~ the follo~ng struc~ure:

C~3CF20(CF2CF20~CF~CF3)0(CF2CF20)2CF~C~3)0-( CF2CF20) 3CF2CF3 b.p. 300~C

Example 18 A mixture of 600g 1,5-pentanedio} and 30g potassi~m hydroxlde w~s heated to 160~C in a 1 lite~
flask. Acet~lene gas w~ bubbled throu~h the sol~tion as it was rapidly stirred. ~he re~ction was stopp~d af~e~ 40 hours ~nd the product was washed ~ith water and di~t~lled to giVR an 85~ yield of pen~anediol di~inyl ether ~b.p 192~C).
A 1 liter ~lask cooled ~o -12~C was char~ed w~th 104g pen~anediol and a traoe of me~hane sulfonic acid. To this solutlon was added 15~g pen~anediol divlnyl ether. The ~olution was stirred rapidly for 2 ~ours. Then slowly w~rmed to room temperature over a 6 hour period to ~ive a v~scou~
polymer having viscosity of 650 cst. ~ lOO~F.

1 0 2 9 ~

The product from the abo~e reaction can be fluorinated in a li~uid phase reactor contalning 1,1,2-~xichloro~rifluoroethane and a sufficient amount of fluorlne to co~plex with all of the h~drogen fluoride for~ed durin~ the reaction. A
perfl~oropoly~ther having t~e follo~ing structure ~s obtalned:

CF3cF2cF2c~2o~c~2cF2cF~cF2cF2oc~(cF3)o]ncF2cF2cF2cF3 Exa~ple lg A mixture of 400 g triethyle~ glyool ethyl ether (2.24 mol), 2~8 g acetalde~yde diethylscetal (1,39 mol), ~0 ml benzene and lO g acidic ion exchange resin were refluxed in a 1 llter stlrred flask equipped wi~h a continuous extractor to remove the by-p~oduct ethanol from the refluxing benzene.
The solutlon was refluxed for 6 hours, then filtered and placed in a rotary evaporator to re~ove the benzen~ sol~ent, The product was fluorinated in a 22 liter stirred tank which contained 5.7 llters of 2-erichlorotr1~luoroethane and llOO g sodiu~
fluori~e po~der. The hydrocarbon, 219 g, wa~
dilu~ed to a ~olu~e of 700 ml with tric~lorotrifluoroethane. The solution W8S
slowly pumped into the fluorinat~on reactor, which was held at -5~C~ over a period of 28 hou~s. Ths fluorine flow was se~ at a level approximately 1~
hi~er than th~t req~lred ~o resct with all of ths organic entering the re~ctor. Filtration of the 1~3 ~-10 29~

crude reactor product followed by dl~tillation yielded 224 g of a clear fluid which analyzed to be:

~F3c~2ocF2cF2ocF2cF2ocF;2cF2ocF(cF3 CF2cF2ocF2cF2ocF2c~3 ~F NMR (~ ppm vs ~FC13):-86.5:0CF(CF3);
-87.4 CF3C~20; -~8.0:CF3CF20;-8~.7 OCF~CF20;
-~6.3: o C~(CF3)0.

Example 20 In an experi~e~ ~ery sim~ to the previou~
one, 400 g dipropylene glycol mono~e~hylether (2.70 mol) w~s ~eacted ~ith 159.~ 8 acetaldehyde diethylacetal (1.35 mol) $~ ~enzene with an acid ca~alyst. Fluorlnation of 250 g of ~he material afforded 480g o~ a perfluorinated fluid havlng the ~ollowing -~tructure:

CF3ocF2c~(cF3)oc~2cF(cF3)oc~cF3)ocF2cF(cF3) (CF3)0C~3 Ex~mple 21 Chloroacetaldehyde ~50 to 55 wt ~ in water) was dlstilled to give a fraction boiling between B7 and 92~C. A 3 li~er st~red fl~sk contaln~ng 128l g of the chloroacet~ldehyde distillate was placed i~ a roo~ tempera~ure water bath. Whlle m~intainin~ a ~emperature below 55~C, 500 ~1 o~ concentrated sulfuric acid was slowly added over ~ one hour period. The ~ixture was stirred for an additionsl 3 ~3-~0294 -46~

days at 53~C, ~hen allowed to sep~rate into two phase~. The lower phase, co~t~ini~g sulfuric acid, was removed with a separ~tory funnel whlle the upper ph~se wa~ placed into a 3 liter flssk equipped with a mech~nical stirrer. Concentrated sulfuric acid ~200 ml) was carefully added to ~he ~ol~tion while the te~perature was held below 60~C wi~h ~ water bath ~hroughout the ad~ltion. The flask wa~ hsld at 50~C for an add~ional 20 hour~ ~esult~ng in a visco~s oil being for~ed. The polymeric product was dissolved ln l liter methylene chloride and the solu~ion w~ washe~ with water several times fol-lowed by a rinse with dllute sodi~m bicsrbonate solution. The organ~c phase was i~olated, dried over magnesi~m sulfate and concen~r~ted to give a dark, viscous product (719 g polychloroace-ta}dehyde). The product was dls~olved in 450 g chloroform and 305 g 1,1,2-trichlorotrifluoroethane to give 8 solution which was metered over a 22 hou~
period into a 20DC fluorination reactor containing 5 5 llters of 1,1,2-trichl~~otrifluoroe~ane.
Following the resction, the solvent was re~oved leaving behlnd ~ ~luid with the followlng structure E p~~ ] n CF2G~

Te~perature ~F Visco~ity (cst.) 100 2,S3 ~76 1.14 134029~

Example 22 Butoxyethoxy~thanol (400 g, 2,47 mol~ was r~acted with 130 8 polymeric chloroAcetaldehyde in 150 ml benzene to ~ flui~ which ~ixtilled at 190~C at approximately 1 torr. The prod~ct (2~6 g) ~as mixed w~ th 500 ml 1,1,2-trichlorotrifluoro~thane and pu~p~d into a 15 liter fluorination reac~or contai~ing 5.7 lL~ers 1,1,2-~richlorotrifluoroethane and 1150 g sodlum fluoride powder. Flu~rine, diluted with approximately four volu~es of nitro~en, ~as metered into the O~C reaetor at a r~te approxi~ately 10~ grea~er tha~ th~t requlred to react ~to~chiometrically w~th ~he polyet~er. The org~nic ~eed r~te ~as sec to allow co~plete sddit~on in approximat~ly ~3 hours. Filtrat~on of the prod~ct and remov~l of the 1,1,2-trichloro~ri-fluoroethane via a distlllation gave ~ fluoroc~bon product which ~ further p~rif~ed by ~ 12 hour fl~orlna~lon at 200~C with 40~ fluor~ne, Approximately 520 g of fluid was reco~er~d ~i~h ~pproxim~ely 50~ b~in~ t~e ~arget mAterial, CF3cF2cF2cF2o~::F2cp2ocF2cF ;~ocF(c~2Gl) b.p. 245.5~C
9F NMR (~ pp~ vs CFC13) -73.3:0CF(C_2C1)0;-81.7:CF3CF2CF2CF20;
-83.3:CF3CF2¢F2C~2o;-88.0 and -8~,7:o~2GF2o;
-96.7:oc-(cF2cl)o;-126 5 cF3cF2¢-2c~2o ~ ~'1029~

Ex~mple 23 Chloroacetaldehyde dimethyl acet~l (12~ g, 1 mol), 1,3-dlchloro-2-propanol (258g, 2 mol) and S~
ion exchange resin were mixed in a 1 llter stirred flask, The mixt~re w~s heated to allow t~e methanol fo~med in the reaceion to slowly distill fro~ the flask. Approximately 70 ml o~ methanol wa~7 recovered over a 6 hour period. ~he rem~ining solution w~s vacuum-distilled and the ~raction ~120 g, 38~ yield) boiling 7Detween 100~C and 145~C at 2 mm Hg was collected, The fluid was ~hown by 19F NMR
and element~l analysis to have the following struc-ture:

(ClCH2)2C:HO~HOCH(CH2C1)2 GH2Cl Th~ above acetAl ~210 g) diluted wi~h a small amount of ~hlorofor~ and 1~l~2-trichlorotrifluoro-ethane was ~etere~ over A 14 hour period into a 22~7 C
~luorination reactor cont~in~ng 5.7 liters of 1,1,2-tri~hlorotr~luoroethane. The crude p~oduct was further ~ea~d with 30~ fluor~ne ~t 200~7 C for several ho7ur~ to give lg7 7 (57% yleld) of clear fluid:

(CF 2 Cl)2cFO~FOcF(cF2cl)2 b.p.: 202DC
1 F N~R (~ ppm vs CFC13):-64.5 and -~5.~(a), -71.0(~) 7 -8~.7(c) and -133.7(b) (ClCF2)2CFO]2 CF(~F2Gl) a b c d Example 24 lnto ~ l liter stirred fl~sk contaln~n~ 300 ml benzene were placed 516 g 1,3-dichloro-2-prop~nol (4 ~ol), l~0 g parafor~aldehyde (4 mol) and lOg ion exchAnge re~in. The ~ixture was refl~xed as ~he w~ter formed ~ur~ng the re~ction w~s continuously re~oved. After refluxing for 6 hours, the reaction mixture was filtered and vacuum-distilled to give 354 g of a product with the following structure:

(ClCH2)2C~oC~2oG~(CH2Cl)2 b.p.: 141~C/0.05 mn Hg.

~ he abo~e acetal (354 g) was mixed with 7~ ~
chlorofor~ and 360 g ~,1,2-trichlorotrifluoroeth~ne and fluorinated over a 24 hour period at 20~C using ~he procedure described in the pre~iou~ exa~ple.
The reaction product was concen~rated and the crude product was further treated with fluorine ~t 2~0~C
to gi~e 430 g of a clear fluid (69~ yield) hav~ng a boiling polnt of 178~C.

F NM~ (~ pp~ vs CFC13~:-45.5(c~, -65.3(a) and 137.1(b) [( 2)2C~~]2 2 a b c :~ 1029~

Example 25 A mlxture of 300g l-propanol (5.0 mol), 231 g epichlorohydrin and 10 g ion exchan~e re~ln waB
refluxed for 22 hours. The reaction mlxture was then ~ooled, filtered and distilled to &lve 281 g of l-chloro-3-propoxy-2-propanol ~74~ yield). ~eaction of this pro~uct with para~ormaldehydc (2.8 ~ol~ ~ave 202 g of product (~ yield) having the follow$n~
s~ructure:

CH3CH2CH20lHOcH2 ~ 2 2 2 3 CH2Cl CH2Cl .p.: 132~C a~ 2 mm H~.

Fluorination o~ the above acstal i~ a 23 hour reac~on at 20~C gave 404 g or produot (81~ yield) ~avln~ th~ fol~owing structure:

CF3cF2c~2ocF2~FocF2oc~cF2oçF2cF2CF3 CF2Cl CF2Cl b,p.: 207~C
F N~R ~ pp~ vs CFC13):-46.3~g), -67.3(f), -80.4(d), -8~.9~a), -84.5(c~, -130.0(b) and -141 . 6(e) [cF3cF2cF2ocF2cF(cF2cl)ol 2CF2 a b c d e f g 02~4 Exa~ple 26 A m~xture of 600 ml ethoxyethanol, 200 g eplchloro~y~rin and 10 g lon exc~an~e ros~n waR
heated to 130~C ~or 20 hour~. The reaction mix~ure was then cooled, filtered and distilled to ~ive 250 g of product whl~ wa~ then reacted with 116 g p~raiormaldehyde to gi~e 266 g of a product boiling above 150~C at 0.01 mm ~g.
~ luorLnation of 261 g of the produc~ in a reactor con~ining 5 liters of 1,1,2-trichlorotri-fluoroethane and 1000 g sodium fluoride ~ave 446 g of perfl~orlnated fluid of whl~h Rpp~oxi~ately 708 h~d the following Rtructure:

CF3CF20CF2CF20CF2qFOC~20C~FCF20CF2CF20CF2CF3 CF2Cl F2Cl b.p, 224VC
9~ ~MR ~ ppm V8 GFC13): -46.4(h), -67.6(g), -80.9~e), -87.6(a), -8~.0(b,c,d), and -141.8~) CF3CF20CF2CF20CF2CF(C~2~1)0CF2~)CF~CF2Gl)CF2 -a b o d e f g h f g e d c b Exa~ple 27 A mixt~re consi~t~ng of lOOg 2-chloro~thanol (12.4 m~ 73g epich~orohydrin (6.2 ~ol) and 20g of an ~cidic ion exchan~e resin ~ere reflu~ed for 24 -~4029~

hours. The mixtur~ was then filt~red to remove the ion exchange res~n and th~ exces~ ~lcohol and unre~oted ep~chlorohydrln we~e re~oved by distil-latlon. The resid~e was ~isti~led under ~ac~u~ and ~he produc~ l-chloro-3-(2-chloroethoxy)-~-propanol (804g, 7S~ y~eld) distilled betwecn 89 and 91~C at 0.05~m ~g, Into a l-lit~r stirred flask was place~ 346g l-c~loro-3-~2-chloro~thoxy)-2-propanol (2 mol), 90g paraformaldehyde (3 mol), lOg ion exchange resin and 300~1 benzene. The mlxture was refluxed for four hours as the w~er for~ed duri~g the react~on was re~oved. Th~ reactlon mixtur~ was filte~ed and d~s~illed to give 2~7g of a product (75~ yleld) wieh the followin~ ~tructure:

ClcH2c~2ocH2c~ocH2o7H 2 2CH2 1H ~C1 CH2C1 Fluorlnatlon of the product (660g) in a typical reactlon ~ 20~C ~ave 1086~ of a product (82~ yield) havin~ the follow~ng ~t~uct~r~:
ClCF2CF20GF2CFOCF20~FCF~OCF2CF2Cl CF2Cl CF2Cl b,p.: 223~C
19~ NMR; (~ ppm v~ CFC13): -46.3~f), -67.3(e), -74.3ta). -81.0(c~, -87.3(b) and -141.9(d) ~ClcF2CF~OCF2CF(cF2c1)0]2 CF2 a b c d e f .. .. . . .

~ 0 2 9 1 Example 28 Into a 1 liter flas~ was c~arged 300 trichloropentaery~hri~ol, (1.5~ mol), 150 ~1 o~
benzene, 10 g ion exchange resi~ ~nd 60 g paraformsldehyde (2 mol). The ~ixture was refluxed as w~ter wa~ beln~ removed continuously.
A portlon of the a~ove product, lg2 ~, wa~
dlluted wi~h 1,17 2-trichlorotrifluoroeth~e to gi~e 210 ml of ~olut~on whlch was pumped ~nto a 22~C
reactor containing 4.3 liters of 1,1,2-tr~chlo~otri-fluoroeth~ne . The reactlon w~s co~plete in approximately 8 hours. The unreacted fluorine wa~
~lushed from the reac~or with nit~ogen ga~ ~nd the produet (30~ ~7 87.8% yield) was recovered by ~istillation:

9F NMR (~ pp~ vs CFC13): -48.9~a), -Sl.l(~), -66.4(b~

E ( cl~2 ) 3 c CF2 o ] 2CF2 a b c Example 29 A m~xture o~ 3~2 g 1~4-cylcohexanedl~ethanol t2.72 mol~, 140 g parafor~aldehyde (4,7 mol~, 200 ml benzene and 10 g of a H ion exchange resin wa~
refluxed for sev~ral hours in a flask containing ~
water separator. A nearly quantitati~e yleld of a sticky solid was obtained after re~o~al of the solvent: by d~stillation.

~ ~02~

Fluorin~lon of 2~3 ~ of the poly~er, d~luted with 220 ~ chlorofo~ and 340 g 1,1,2-trichlorotri-~luoroethane in a reactor ~lO~C) coneaining 4.8 liters 1 t l,~-~richlorotrifluoroethsne and 1300 g sodlu~ fluorid~ power, gave 440g of a perfluoro-polyether ~aving ~he fol~owing structure:
CF2 ~F2 ICF2~FCF2CF2 F CF2~CF2~]n Example 30 Into a 1 li~er fl~k were placed 350 g ~eeraethylene glycol ~1.8 ~ol), 300 ml ben~ene, and 10 ~ ion exchange resin. The ~ixture was refluxed ~or 1 hour to remove ~ny moist~re presen~. To the ~ixture was added 200 ml di~ethoxypropane. The distillate was continuou~ly ~emoved over ~ 2-hour period in 50 31 increments, which were extracted with water to removR the ethanol formed in t~e react~on. After drying, the distlllate wa~ returned to t~e flask. An additional 200 ml dimethoxypropane ~as added and the dlstillate was collecee~, extracted, dried, and return~d ~o the flask for an additional 3 hours. ~emoval of the resin and solven~ yielded 410 g of a polymeric fluid having a viscosity of 5~0 cst. at 30~C.
Fluorina~ion of 336 gr~ms of the polyether ~n lO~C reactor ~ontaini~g S liters of l,l,~-trichloro-trifluoroethane and 1420 g sodium fluoride powder gave 642 g of a perfluoropolyether ~69.8~ yield).

.

1~4~2~

F ~M~ ppm v~ CFC13): -S5.8(a), -76.3(e), -87.3~d), -~8.6(c) and -90.5~b) CF30 [CF2(CF20G~2)3 ~20C~CF3)2 ~]n a b c c d e Example 31 A mixture of 300 g pentanedlol t2.88 mol), 450 ~ chloroacetaldehyde/water mixture having a bo~ling poin~ b~tween 87 and 92~C and lS0 ml benzene W8~
refluxed in a flalk conta$ning a water sepa~ator.
Approxi~ately S gra~s of an ~cidlc lon exchan~e resin w~s adde~ to ~atalyze the ~eaction. Aft~r refluxi~g for approximate}y f~ve hours the solution wa~ filterad and the benzene ~a~ removed by distillation to leave ~ residue (approximately ~00 ~) having a visco.city of 9,700 cst. at 100~F.
Fluorin~tion of 318 g of the polymer, diluted wlth 235 g chloroform snd 375 g 1,1,2-trichlorot~i-fluoroetha~e, in a 12~C ~esctor co~aining 5 liters of 1,1,2-trichlorotrifluoroethane and 1200 g ~odium fluoride powder gave 623 g (84~ yield) of the fluorlnat~d polye~her in ~ 22-hour reaction.

F ~M~ (~ ppm vs ~FC13~

-73,4(h), -74.3(c), -81.6(~ 82.3(d), -87.1(g), -122.1(f), -125,3(e) and -126.3(b) ~4029~

C~3cF2cF2cF2o[c~2cF2cF2cF2cF2ocF(cF2cl)o~ CF2CF2-a b b c d e f e d g h ~ b b a Eq~ivalents Those skllled in the ~rt w~ll recognize or be able to ascertain using no more than routine experimentatlon many equivalents to the ~pecific embodi~ent~ of the lnvention described hereln. Such ~qu~valents are int~nded ~o be encompassed by the following cla~m~;

. . , -SUPPLEMENTARY DISCLOSURE ~~ 4~ 2 g 4 sriefly, in one aspect, this invention provides a perfluocinated gem-alkylenedioxy composition which can be normally liquid and which consist or consist essentially of one or a mixture of perfluorinated gem-alkylenedioxy compounds, viz., perfluoroacetal or perfluoroketal compounds, having 6 to 100, and preferablyl at least 12, e.g. 12 to 50, carbon atoms, which are useful, for example, as lubricants, hydraulic fluids, liquid heat transfer media such as thermal shock fluid and vapor phase soldering fluids In another aspect, this invention provides a normally liquid, perfluoroacetal composition which is useful, for example, as a thermal shock testing fluid. The composition can consist or consist essentially of a saturated perfluoro-1,1-bis(alkyloxy)alkane compound as the single molecular species in the composition (and such composition is hereafter on occasion referred to for brevity as a "single molecular perfluoroacetal composition" or "unimolecular~ composition or fluid).
Said compound (hereafter referred to on occasion as a perfluoroacetal compound) thus has a perfluoro-l,1-alkylenedioxy moiety, -O-CF-O-, but can have another perfluoro-l,l-alkylenedloxy moiety, provided it is separated from the other by at least two catenary carbon atoms of a perfluoroalkylene moiety. In another aspect, this invention provides a normally liquid, perfluoroacetal composition which consists or consists essentially of a mixture of two or more such compounds (and such composition is hereafter referred to on occasion for brevity as a "mixed perfluoroacetal composition"~ of --discrete, non-random molecular weights, said compounds pceferably being those having complementary properties, .A~'' 1 3~029~ 1 for example, boiling points and pour points each within respective narrow ranges, desired for a particular use of the composition, e.g. for use as a heat exchange medium.
Unless otherwise stated or apparent, the term ~perfluoroacetal composition" as used herein means that consisting or consisting essentially of one or a mixture of said compounds, that is, the term is used in a generic sense to cover the single molecular and the mixed perfluoroacetal compositions of this invention.
he perfluoroacetal compound can have one or a few, e.g. 2 or 3, chlorine atoms, each of which is bonded to carbon atoms other than those carbon atoms to which an ether oxygen atom is bonded; stated otherwise, the compound can have 1, 2, or 3 carbon-bonded chlorine atoms in place of 1, 2 or 3 carbon-bonded fluorine atoms of the alkyloxy moieties if the carbon atoms to which the chlorine atoms are bonded are other than those to which the ether oxygen atoms are bonded.
The perfluoroacetal composition, which is liquid at ambient conditions, e.g. 20 C at 740 Torr, generally has a boiling point greater than 20~C, preferably a boiling point of at least qO~C, and more preferably a boiling point greater than 125~C, e.g. 180~C, and can have a boiling point as high as 300~C. Generally the perfluoroacetal compound has at least 6 carbon atoms, and can have as many as 24 carbon atoms or even up to 30 carbon atoms, but preferably the compound has at least 12 carbon atoms, e.g. 12 to 17 carbon atoms. Where a perfluoroacetal compound is a chlorine-containing perfluoroacetal compound, its effect on the boiling point of the perfluocoacetal composition will be approximately the same as that of a perfluoroacetal compound which does not contain chlorine atoms and has a higher carbon content. Generally, one chlorine atom will have about the same effect on boiling point as 1.5 to 2 carbon atoms.
A particularly useful property of the perfluoroacetal composition of this invention is its wide liquid range, meaning it is normally liquid over a wide temperature ~':

range; in fact, some of them can be considered as having exceptionally wlde liquld ranges. A feature of the perfluocoacetal compositions of this lnvention i5 that the perfluoroacetal compound or compounds thereof are each of well-defined, definite, certain, and known structure of a non-random nature and with fixed carbon, fluorine, and oxygen ratios and of a definite (or pacticular or distinct) molecular identity. In the mixed perfluoroacetal compositions, specific molecular structures and amounts of each compound in the mixture are features which can be completely predetermined and the mixture made by mixing or blending selected single molecular perfluoroacetal compositions or the mixture made as such as a reaction product of the corresponding precursor mixture of acetals. These features are in contrast to those perfluoropolyether chemicals which are --polymeric or oligomeric in nature and have a distribution of molecular weiqhts, those which have a random structure, or those which are a random mixture of compounds. The control over the nature of the single molecular perfluoroacetal compositions of this invention is a feature which means that their physical properties, particularly thelr low temperature viscosity and their discrete boiling point, are invariable under conditions of use, for example where in use as a thermal shock fluid some of such single molecular weight perfluoroacetal composition is lost through volatilization. Some of the mixed perfluoroacetal compositions can have these advantages if the perfluoroacetal compounds ln the mlxture are judiciously selected, for example by empirically selecting those with the desired boiling points and low temperature viscosities.
The above-described features of the compositions of this invention advantageously contribute to their usefulness as heat exchange liquids, such as thermal shock testing fluids. The perfluoroacetal compositions also have utility as hydraulic fluids, as pump fluids for corrosive environments, and as fluids for vapor-phase '.1 3 . . . . . . .

condensation heating for soldering and polymer-curing applications. Their low temperature viscosities are especially low compared with the viscosities of prior art perfluorinated polyether fluids which have a distribution of molecular weights and compositions. These low viscosities render the perfluoroacetal compositions of this invention especially effective, particularly in comparison with the prior art fluids, as heat transfer media at low temperatures.
In another aspect of this invention, the perfluoroacetal and perfluoroketal compositions are prepared by direct fluorination of their perfluorinateable, saturated or unsaturated acetal or ketal precursors which can be fluorine-free or partially-fluorinated and chlorine-free or partially chlorinated. ("Perfluorinateable" means the acetal or ketal precursor contains carbon-bonded hydrogen atoms which are replaceable with fluorine and any carbon-carbon unsaturation in the precursor can be saturated with fluorine.) The resulting perfluoroacetal or perfluoroketal compounds can be made with the same number and spatial arrangement of carbon atoms as the precursors thereof. The fluorination can be carried out at a temperature between -80 C and +150 C or at moderate or near ambient temperatures, e.g. -20 C to +50 C, preferably between -10~C and +40 C, with a stoichiometric excess of fluorine gas, which is preferably diluted with an inert gas, such as nitrogen, helium, argon, perfluoromethane, or sulfur hexafluoride, to minimize or avoid hazards and to control the amount of heat generated upon initial contact of the precursor with the fluorine.
A class of perfluoroacetal compositions of this invention is that whose members consist or consist essentially of one or of a mixture of perfluorinated ' ~ .

- 61 - ~3~029~
acetal compounds whlch fall within the follo~l~g representational general formula:

Rl(OR~)~[OfF(ORt)yJ~OfFO~~R~O)~R5 wherein: R~ and R~ are each independently selected from the group consisting of Cl to C" preferably Cl to C6, linear or branched perfluoroalkyl, C~ to C~, preferably C
to C6, linear or branched chloroperfluoroalkyl, and unsubstituted or lower alkyl-substituted perfluorocycloalkyl or chloroperfluorocycloalkyl wherein the lower alkyl substituent has 1 to 4 carbon atoms and the number of ring carbon atoms in the cycloalkyl is 4 to 6, preferably 5 or 6; R~, Rt, and R~ are each independently selected from the group consisting of C2 to C~ linear or branched perfluoroalkylene and C~ to C~
linear or branched chloroperfluoroalkylene; each R~ is independently a fluorine atom or perfluoroalkyl with 1 to 4 carbon atoms, and is preferably perfluoromethyl or, more preferably a fluorine atom; x and w are each independently an integer of 0 to 4; y is an integer of l to 6, preferably 1 to 3; z is an integer of 0 or 1; and the total number of carbon atoms in said compound can be 6 to 30, preferably at least 12, e.g. 12 to 17, and more preferably 13 to 14 because of the extremely low viscosity at low temperatures, e.g. less than about 300 centistokes at -70~C, coupled with high boiling point, e.g. above about 175~C, that the compositions have when the total carbon atoms are 13 or 14. (The term "chloroperfluoro-n is used herein to describe a perfluoro moiety in which 1 or 2 fluorine atoms are replaced in a sense by chlorine atoms, e.q. as in the case of ClC2F~- or -CF2CF(CF2Cl)-.) The perfluoroacetal compositions preferably have a boiling point in the range of 160~C to 250~C, and more preferably in the range of 175~C to 200~C.
The perfluoroacetal compounds of this invention contain at least one perfluoro-1,1-alkylenedioxy unit, A

.... . . .

- 62 - ~t, f~0 29~
e.q. -OCF(R~)O- in formula I, wh~ch can be located approximately at the center of the perfluoroacetal molecule, but a perfluoroacetal compound can contain two perfluoro-~ alkylenedioxy units separated by at least two catenary carbon atoms of a perfluoroalkylene moiety and each of the units located at approximately the center of a different molecular half of the compound. Here, "approximately at the center~ means having about the same number, plus or minus about one, of perfluoroalkyleneoxy units on each side of the molecule (in the case of a single alkylenedioxy unit) or molecular half (in the case of two such units). The acetals having one perfluoro-1,1-alkylenedioxy unit which is centrally located are generally more easily prepared because their precursors are readily available materials.
A particularly useful subclass of the perfluoroacetal compositions of this invention is that whose members consist or consist essentially of one oc a mixture of two or more perfluoroacetal compounds falling within the following representational general formula:

C F~ l(Oc~F~.-OcF[(cF2)~F]O-(c.~F2.~o)bcn~F2n~

wherein: each n and n' is independently an integer of 1 to 6, each m and m' is independently an integer of 2 to 4, a and b are each independently an integer of 0 to 4, and p is 0 or 1 (if p is 0 then the central moiety is -OCF~O-and if it is 1 then the central moiety is -OCF(CFl)O-), each said compound preferably having 13 to 14 total carbon atoms, said composition having a viscosity at -70~C of less than about 300 centistokes, preferably less than about 200 centistokes.
In another aspect, this invention also provides a method of transferring heat from an article, such as an electronic component or device, to a cooling liquid, the method comprising directly contacting_the article with an above-described perfluoroacetal composition of this invention.

.

~- - 63 - ~ 1029~
This invention further provides a method of inducing a thermal shock to an article, such as an electronic component or device, for example for purposes of testing the integrity or soundness of the article as described earlier herein, the method comprising the following steps:
a) heating a first bath of a heating liquid to a temperature above ambient temperature;
b) cooling a second bath of a cooling liquid to a temperature below ambient temperature; and c) sequentially:
i) immersing the article in an initial bath which is one of said first and second baths and allowing said article to come to the temperature of said initial bath before removing said article from said initial bath, and ii) then immersing said article in the other of said first and second baths and allowing said article to come to the temperature of said other bath before its removal therefrom;
wherein said liquids are inert, thermally stable, perfluorinated liquids, at least one of which is, but preferably both are, a perfluoroacetal composition of this invention, more preferably the version which is a single molecular perfluoroacetal composition.
When a prior art fluorochemical made up of a mixture of molecular weights is used as a single thermal shock fluid, the lower molecular weight components of such fluid can boil off from the heating bath and the remaining higher molecular weight components can lead to increased viscosity through pollution or contamination of the cooling bath. The single molecular perfluoroacetal composition of this invention, which is essentially a single perfluoroacetal compound, does not have these disadvantages of prior art fluids (which have a distribution of molecular weights). The version of the perfluoroacetal composition of this invention which is a mixture of perfluoroacetal compounds also can overcome these disadvantages if each of the compounds in the mixture have the same or about the same boiling point, e.g. boiling points ..

- 64 - ~?~'102~

within a 10 to 15~C range, and viscosity, e.g. viscosities at -70~C of up to ~00 cs, necessary to maintain the desired bath temperatures.
The perfluoroacetal compositions and perfluoroketal compositions of this invention may be prepared from their hydrogen-containing, saturated or unsaturated, non-fluorinated or partially-fluorinated, non-chlorinated or partially-chlorinated hydrocarbon analog acetals and ketals which are perfluorinateable by direct fluorination. Although the perfluorinated products may contain small amounts of fluorinated materials having one or a few residual hydrogen atoms, the perfluoroacetal and perfluoroketal compositions of this invention are, except for any chlorine content, essentially fully-fluorinated, i.e. perfluorinated, with a residual carbon-bonded hydrogen content of generally less than about 0.4 mg/g, usually less than 0.01 mg/g, and preferably less than about 0.1 mg/g, e.g. 0.01 to 0.05 mg/g.
This residual hydrogen content can be lowered or essentially completely removed (as well as traces of undesired carboxylic acid derivatives such as terminal acyl fluoride groups resulting presumably from chain degradation reactions) upon treating at elevated temperature, e.g. at 150~C or higher, e.g. 175~C or even 260 C, the fluorinated product with fluorine, for example fluorine diluted with an inert gas such as nitrogen, such treatment being referred to hereinafter on occasion as the "polishing" finishing technique.

''~'' . .

- 65 - ~ ~4029 Suitable liquids u~ful as liquid phas~ reaction media are chlorofluorocarbons such as Freon~ 113, 1,1,2-trichlorotrifluoroethane, and Freon~
fluorotrichloromethane, and chlorofluoroethers such as 2,5,5-trichloroperfluoro-2-butyl tetrahydrofuran, perfluoro-bis(chloroethyl)ether, and perfluorinated polyepichlorohydrin liquids, which media generally will function as good solvents for non-fluorinated precursors, and Fluorinert electronic liquids FC-75, FC-72, and FC-40, perfluoroalkanes such as perfluoropentane and perfluorodecalin, perfluoropolyethers such as ~rytoxT~ and FomblinSM, perfluoroalkanesulfonyl fluorides such as perfluoro-1,4-butanedisulfonyl fluoride and perfluorobutanesulfonyl fluoride, and the perfluoroacetal compositions of this invention, and this latter group of media, i.e., perfluoroalkanes, etc., generally will function well as solvents for some precursors or as reaction media for forming dispersions of other precursors. Mixtures of such liquids can be used, e.g. to get good dispersion of precursor and intermediate reaction products. The reaction media are conveniently used at atmospheric pressure. Lower molecular weight members of the above classes of reaction media can also be used, but elevated pressures are then required to provide a liquid phase. The fluorination reaction is generally carried out at a temperature between about -10~C to +50~C, preferably between about -10 C to 0~C if a hydrogen fluoride scavenger is used,~-and~if-such scavenger~ls not~ ~
used, between about 0 C to 150~C, preferably about 0~C to 50~C, most preferably about 10~C to 30~C, the temperature ..,~ f ~ 3~029~
-being sufficient to volatilize the hydrogen fluoride by-product and with the aid of the inert gas, flowing at a sufficient rate, cause the purging of the by-product from the - fluorination reactor as it is generated. At these temperatures, the liquids utilized as reaction media do not react appreciably with the diluted fluorine and are essentially inert. The reaction medium and other organic substances may to some extent be present in the gaseous reactor effluent, and a condenser may be used to condense the gaseous reaction medium and such substances in the effluent and permit the condensate to return to the reactor. The condenser should be operated so as to minimize or prevent the return to the reactor of hydrogen fluoride by-product (which would have an adverse effect on yield of perfluorinated product if allowed to remain in the reactor during fluorination). The return of the hydrogen fluoride can be minimized or prevented by selective condensation of the organic materials while allowing the hydrogen fluoride to pass through the condenser, or by total condensation into a separate vessel of both hydrogen fluoride and the organic materials followed, if desired, by separation of the hydrogen fluoride as the upper liquid phase and the return of the lower liquid phase. The reaction may be carried out in a batch mode, in which all of the precursor is added to the liquid prior to fluorination to provide a precursor concentration of up to about 10% by weight, and the fluorine-containing gas then bubbled through the precursor-containing liquid. The reaction can also be carried out in a semi-continuous mode, in which the precursor is continuously pumped or otherwise fed neat, or as a diluted solution or dispersion or emulsion in a suitable liquid of the type used as a reaction medium, into the reactor, e.g. at a rate of about 1 to 3 g/hr into 400 mL of liquid reaction mixture, as fluorine is bubbled through, e.g. at a fluorine flow rate of about 40 to 120 mL/min and an inert gas flow rate of about 150 to 600 mL/min. The fluorination can also be carried out in a continuous manner: the precursor (either neat or dissolved or dispersed in a suitable liquid of the s .. . . ...

~ 67 - ~ 34a2~

type used as a reaction medium to form a solution or emulsion) being continuously pumped or otherwise fed into the reactor containing the reaction medium as the fluorine-containing gas is introduced, as described above, and the stream of unreacted fluorine, hydrogen fluoride gas, and inert carrier gas being continuously removed from the reactor as is a stream of liquid comprising perfluorinated product, incompletely fluorinated precursor, and inert liquid reaction medium, and the necessary separations being made to recover the perfluoroacetal composition, and, if desired, with recycling of the unreacted fluorine and the incompletely fluorinated precursor. The perfluorinated produ~t frn~ tn~
batch mod~ generally wi , ~ ~ .
f~

.. .. .,~ ~

- 68 - ~31023~

have significant residual hydrogen, e.g. about 7 mg/g, whereas the perfluorinated product made by the contlnuous or semi-continuous mode will generally have less residual hydrogen, e.g. less than 0.1 mg/g. In general, the continuous addition of precursor is preferred and provides a higher yield, better product quality, and more efficient use of fluorine, though the batch mode has similar advantages if the "polishing" finishing step is used.
Due to the extremely high exothermicity of the fluorination reaction, a cooled liquid or ice bath is generally employed in order that acceptable rates of reaction may be achieved. When the reaction is complete, the reactor is purged of fluorine and the reactor contents are removed.
In the solids fluorination technique, the reactor contents can be mixed with Freon 113 or Fluorinert FC-72 solvent, the resulting slurry filtered, and the solvent stripped, e.g. by vacuum distillation, to provide crude perfluorinated product.
Where the fluorination is carried out by the liquids fluorination technique in the presence of a hydrogen fluoride scavenger, the spent scavenger can be separated by filtration or decantation from the liquid reactor contents and the latter then distilled to separate the reaction medium from the crude perfluorinated product. Where the fluorination is carried out by the liquids fluorination technique without using the scavenger, the reaction product mixture can be distilled to recover the perfluorinated product.
The crude perfluorinated product can be treated with a base, e.g. sodium hydroxide, to remove acid and hydride impurities or treated, e.g. at a temperature above 150~C, by the polishing finishing technique to remove hydrogen and acid impurities and the so-treated product distilled. The order of these purification steps can be varied to obtain best results.
The precursor acetals used for preparation of the perfluoroacetal compositions of this invention can be prepared in a variety of ways by reaction of alcohol(s) with appropriate co-reactants. Symmetrical acetals result upon heating two moles of a single alcohol with an aldehyde, e.g.

,'~;

- ~' 3~0294 formaldehyde, under acld catalysis, with removal of water during the reaction, as illustrated in Equation 1.

2ROH + R'CHO --> ROCHOR + H20 Eq. 1 Lower acetals can be converted to higher ones by heating with the higher alcohol under acid catalysis, as illustrated in Equation 2.

C ~R n 2ROH + R'O HOR' --> ROCHOR + 2R'OH Eq. 2 A third route, to symmetrical acetals, as illustrated in Equation 3, involves basic conditions and is useful for hindered or acidic alcohols in which the above acid-catalyzed equilibria are unfavored. Under phase transfer catalysis, a mixture of NaOH, or preferably ROH, and the alcohol displaces chloride from methylene chloride.

2ROH + 2ROH + CH2C12 --> ROCH2OR + 2KCl +2H20 Eq. 3 The preferred route to asymmetric acetals requires prior formation of the alpha-chloroalkyl derivative of one alcohol and subsequent reaction with the second alcohol under basic conditions, as illustrated in Equations 4 and 5.

ROH + R'CHO + HCl --> ROCHCl + H20 Eq. 4 IR' IR' ROCHCl + RnOH + KOH --> ROCHOR" + KCl +H20 Eq. 5 This latter reaction is also the preferred method to prepare precursors containing two alkylenedioxy units.

The other methods illustrated in Equations 1-3 can be used for preparing those precursors with two of such units, although yields are lower due to competinq oligomerization.
In the schemes illustrated in above Equations 1 to 5, mixtures of alcohols, aldehydes, and/or acetals can be used as reactants to prepare mixtures of precursors that are fluorinated to make perfluoroacetal compositions of this invention which are mixtures of perfluoroacetal compounds. Thus, the process of Equation 1 can be modified by use of two different alcohols, as lllustrated in Equation 6.

R.n ~rl 4ROH + 4R'OH + 4R~CHO --> 2ROCHOR' + ROCHOR +

~ n R'OCHOR' + 4H20 Eq- 6 ~' ~ ~1029~
Useful precursor acetals for conversion by direct fluorination to the perfluoroacetals of this invention include each of those in the following list of materials and mixtures of 2, 3, or more thereof:

CH3(CH2)50CH20(CH2)sCH3 CH3(CH2)30cH20(cH2cH2o)2(cH2)3cH~

2 ~ {

Cl ~ OCH20 ~ Cl ~CH2 OCH2 OCH2~

CH3(CHz)60CH20(CH~)6CH3 CH (CH2)2(ocH2cH2)3ocH2o(cH2cH2o)3(c 2)2 3 CH =cHcH2(ocH2cH2)3ocH2o(cH2cH2o)3c 2 2 CHz CHCH20(CH2)30cH2o(cH2)3ocH2cH~cH2 - 72 ~ 0 2 9 CF~CHFCF20(CH~)30CH20(CH2)~0CF2CHFCF~

CH,(CH2)2(0CH2CH2)~0CH20(CH2CH20)~(CH2)2CH3 CF3CHFCF20C~H60CH~OC3H60CF2CHFCF3 and CH3[0C3H6]~0CH20[C3H6 0 1 2 CH3 (where C3H6 can be either -CH2~H- or -ICHCH2- or a mixture of both) ClCH2CH2OCH2CH2OCH2OCH2CH2OCH2CH2Cl CH3(CH2) 3 ocH2cH2ocH2ocH2cH2o(cH2) 3 CH
CH3(cH2)3(ocH2cH2) 2 ~CH2 ~( CH2 CH2 ~) 2(CH2)3CH3 CH3(cH2)3ocH2ocH2c-ccH2ocH2o(cH2)3cH3 CH3cH2(ocH2cH2) 2 ~CH2 ~ ( CH2 CH2 ~ ) 2 CH2CH3 CH3(CH2) 2 ( OCH2 CH2 ) 2 ~CH2 ~( CH2 CH2 ~ ) 2 (CH2)2CH3 3OcH2cH2ocH2(ocH2cH2)3ocH2ocH2cH2OcH3 3 C 2ocH2cH2ocH2(ocH2cH2)3ocH2ocH2cH2ocH2cH

CH3.CH20CH2CH~OCH2(0CH2CH2)20CH20CH2CH~OCH2CH3 CH30CH2CH20CH20(CH2CH20) 2 (CHl)3CH3 CH3cH2(ocH2cH2) 2 OCH20(CH2)sCH3 CH3cH2ocH2o(cH2cH2o)3(cH2)3cH3 CH3(CH2)30CH2CH20CH(CH3)0CH2CH20(CH2)3CH3 CH3(cH2)3ocH2cH2OcH(cH2cH2cH3)OcHzcH2o(cH2)3cH3 ~ C

,, , , . . . ~ , .. ... . .. . ..

, 1 02g i ( CH3 ) 3 COCH, CH2 OCHl OCH2 CH2 OC ( CH3 ) 3 C3 H7 OCH2 CH2 OCH ( CH2 Cl ) OCH2 CH2 OC3 H, CH3 OCH2 CH2 OCH2 CH ( CH3 ) OCH2 OCH ( CH3 ) CH2 OCH3 CH3 CH2 OCH2 CH ( CH2 Cl ) OCH~ OCH ( CH2 Cl ) CH2 OCH2 CH3 CH3 CH2 OCH2 CH2 OCH2 CH2 OCHZ OCH2 CH2 O ( CH2 ) 3 CH3 C, Fl 5 CH2 OCH2 OCH2 C, Fl 5 C3 F, CH2 OCH2 CH2 OCH2 OCH2 CH2 OCH2 C3 F7 Representative examples of the perfluoroacetal compounds of this invention include the perfluorinated counterparts of the precursor acetals listed above. Where the precursors have unsaturation, the corresponding perfluoroacetals thereof are saturated.
The perfluoroacetal compositions of this invention generally have surprisingly low viscosities at low temperatures compared with the viscosities of commercial GALDENR perfluoropolyether immersion fluids of comparable molecular weiqht, which commercial fluids contain a distribution of molecular compositions. These low viscosities render the perfluoroacetal compositions of this invention especially effective, particularly in comparison with the prior art fluids, as heat transfer media at low temperatures. A preferred utility for the perfluoroacetal compositions of this invention is in cooling an article to a temperature below ambient, e.g., a temperature far below ambient temperature, such as -65~C.
Such cooling may take place as part of a thermal shock method which can be used to temper or test a material. An especially preferred utility is use in the thermal shock method of this invention, which is preferably car-ried ~ut in accordance with Condition B or C of U.S. Military Standard MIL-STD-883C, Notice 4, method 1011.6, ~Al ~

- 3.. 3llO2~
incorporated herein by reference, with a perfluoroacetal composition of this invention substituted for both of the fluids specified in that procedure. The thermal shock method may also be carried out using two thermal shock liquids, one being a conventional electronic testing fluorochemical liquid which may be used in either of the two baths, and the other being a perfluoroacetal composition of this invention which is used in the remaining bath. Examples of suitable conventional liquids include the inert, perfluorinated organic compounds available from 3M as FLUORINERT Electronic Liquids described in product bulletin No. 98-0211-2267-0(161)NPI
issued February 1986.
The thermal shock method of this invention using a single thermal shock liquid can be carried out, for example, as follows in accordance with MIL-STD-883-1011.6, Condition C. The article, such as an electronic component or device to be tested, can be preconditioned by being immersed in a heated bath of a perfluocoacetal composition of this invention at an elevated temperature between 150~C
and 160~C for a minimum of 5 minutes. Immediately upon conclusion of the preconditioning period, the article is transferred to a cooled bath of the perfluoroacetal composition at a temperature between about -65~C and -75~C. The article is held at the low temperature for 5 minutes, at the end of which time it must itself reach -65~C, and it is then transferred back to the heated bath of the perfluoroacetal composition. The article remains at the high temperature for 5 minutes. Transfer time from the high temperature bath to the low temperature bath and from the low temperature bath to the high temperature bath is less than 10 seconds. The duration of the test is generally about 15 complete cycles, where one cycle consists of immersion in and removal from the heated bath of the perfluoroacetal composition and immersion in and removal of the article from the cooled bath of the perfluoroacetal composition. After completion of the final cycle of a thermal shock test, an external visual .. .

2 9 ~
examination of the article is generally pecformed without magnification or with a magnifying viewer. Typical effects of thermal shock on defective articles include cracking and delamination of substcates or wafers, opening of terminal seals and case seams, and changes in electrical conductivity due to moisture or to mechanical displacement of conductors or insulating materials. The electronic performance of the electronic components can be determined and compared with the electronic performance of the article prior to thermal shock testing.
In an alternative thermal shock method of this invention using two thermal shock liquids, a perfluoroacetal composition of this invention can be placed in the heating bath of a thermal shock apparatus and a different perfluorinated, inert liquid, such as a conventional, perfluorinated, inert thermal shock testing liquid, e.g., FLUORINERT FC-77, is placed in the cooling bath. In this alternative method, the manipulative steps and conditions used can be the same as those described above for the single thermal shock method. As the alternative thermal shock method is practiced, the perfluoroacetal composition, when carried over into the cooling bath, will generally not raise the viscosity of the cooling bath to the extent that a conventional thermal shcck heating liquid, e.g., FLUORINERT FC-40, does over extended use.
In another alternative thermal shock method of this invention using two thermal shock liquids, a perfluoroacetal composition of this invention can be placed in the cooling bath of a thermal shock apparatus and a different perfluorinated, inert liquid, such as a conventional, perfluorinated, inert, thermal shock testing liquid, e.g., FLUORINERT FC-40, is placed in the heating bath. In this alternative method, the manipulative steps and conditions used can be the same as those described above for the single thermal shock method. As the thermal shock method is practiced, the perfluocoacetal composition of this invention, when carried ovec into the heating - 76 - ~ 3 '10 2~ i bath, will generally not volatilize from the heating bath to the extent that a conventional thermal shock cooling liquid, e.g. FLUORINERT FC - 77, does over extended use.
While the methods of this invention of inducing a thermal shock can be applied to almost any article which is immersible in the baths used in the method, the methods are preferably used to induce a thermal shock in an electronic device or component to evaluate the electronic component's response to the thermal shock. Examples of electronic components and devices include inteqrated circuits, integrated circuit assemblies, micro-electronic components and devices, ceramic and plastic carriers for electronic chips, and assemblies of micro-electronic components, e.g., integrated circuits, transistors, diodes, resistors, capacitors, and the like.
Apparatus suitable for performing a thermal shock test are available from many manufacturers, e.g., Blue M
Engineering, Blue Island, IL; Cincinnati Sub-Zero Products, Inc., Cincinnati, OH; Maruberi, Santa Clara, CA;
Ransco Industries, Oxnard, CA; Standard Environmental Systems, Inc., Totowa, NJ; and Thermodynamic Engineering, Inc., Camarillo, CA. Each of these apparatus possesses particular features and makes different demands on the fluid, especially in the cold bath. While some baths in such apparatus can tolerate a higher cold bath viscosity than others (e.g., at a cold bath temperature of -65~C), others tolerate a maximum in viscosity of about 600 cs at -70~C. Preferred perfluoroacetal compositions used in this invention have cold bath viscosities below the above value and thus have general utility in such apparatus.
This variability in apparatus apparently relates to the observation that fluid in the vicinity of the cooling coils or panels of the apparatus tends to be somewhat cooler (e.g., -80 C or -85 C) than the set temperature of the cold bath and, as a result, problems in maintaining the set point can occur due to thickening of this fluid and/or due to the formation of an insulating coating on the coil. For prior art fluids and, by inference, many of the fluids of this invention which have low viscosity at -70~C, but not at -85~C, this can be overcome by increased mechanical agitation. However, in order for a fluid to be most useful in heat transfer applications, good fluidity, i.e., low viscosity, at temperatures as low as -85~C is especially desirable. Single molecular weight perfluoroacetal compositions of this invention offer an advantage over fluids which contain higher molecular weight components which can selectively congeal on cooling coils and also have the advantage that thermal or mechanical losses in use do not change the composition (and, therefore, properties) of that volume or residual amount remaining. The desiqn characteristics and specifications for a number of commercially available apparatus are described in a product bulletin of Ransco Industries, Oxnard, CA, entitled "Thermal Shock Temperature Cycling, Product Bulletin 7000 Seriesn.
Minor amounts of optional components may be added to the perfluoroacetal compositions, e.g., thermal stabilizers, dyes, etc., to impart particular desired properties.
The perfluoroacetal compositions of this invention can also be as additives for other inert fluorochemical liquids, used, for example, as thermal shock fluids, hydraulic fluids, heat exchange media, and other working fluids, to modify or adjust their viscosities or pour points. The pour points given in the examples below were estimated by first immersing a thermometer in a sample of distilled liquid product contained in a glass vial and then placing the vial in a liquid nitrogen or dry ice bath to cool the sample to a solid, glassy state. The vial was then allowed to warm slowly and the temperature at which complete fluidity was ~h'~
.. .. . .

.. .. .

- 78 - ~ ~40291 attained wa~ noted and recorded as the pour point. The viscosity in these examples was measured by conventional means using a wescan viscometer timer and Cannon-Fenske viscometer tubes, as described in ASTM D446-74 (reapproved in 1979~. Stable low temperatures for the viscosity measurements were achieved using Fluorinert FC-75 as the bath medium; the temperature of the perfluoroacetal composition was measured with a resident thermocouple.

EXAMPLES

~xample 32 A cylindrical brass reactor (about 7.5 cm in diameter and about 30 cm long, with a sealed bottom and a removable head) was fitted with a copper tube through the head reaching to within about 5 cm of the bottom as the gas inlet and a hole in the head was fitted as the exit. An intimate mixture of 30.0 g (0.139 mol) bis(n-hexyloxy)methane (prepared by the procedure described in Example 7 usinq methylene chloride as a source of the formal moiety) and 210 g t5.0 mol) NaF
powder was placed in the reactor, which was then installed horizontally in a water-ethylene glycol bath and rotated at about 20-30 rpm. Fluorine and nitrogen were mixed prior to entry. The bath was cooled to -17~C and the gas mixture of 60 mL/min fluorine and 240 mL/min nitrogen was begun. An exotherm of abouat 2 to 5~C was registered by an internal thermocouple. After 22 hr, the exotherm was <1~C and the temperature was increased by 10-15~C
increments over the next 8 hrs to 55 C. At hour 25, the nitrogen was reduced to 120 mL/min and, at hour 29, to 60 mL/min. The fluorine was stopped at the 30th hr. The resulting white powder (364.2 g) was combined with 7.0 g of condensate from a cooled trap tcontaining dry ice) in line after the condenser and was washed three times with 500 mL Freon 113. The--~ombined Freon 113 washings was stripped on a rotary evaporator at less than 25~C. The residue, 72.4 g, was distilled on a short path to 19.4 g .~ ,j .
"~

134029~

(19%) of 88% pure perfluoro-bis(n-hexyloxy)methane ~structure confirmed by fluorine nuclear magnetic resonance and gas chromatography-mass spectrometry), having a boiling range of 120-130 C/60 Torr, a pour point of -70~C, and a viscosity greater than 2000 cs at -85~C.
47.4 g of higher-boiling materials was also isolated.
Examples 33, 34 and 35 Using the fluorination technique of Example 32 and formals prepared by the methylene chloride route of Example 38 three perfluoroacetal compositions were made:
Ex. 33,perfluoro-bis (cyclohexyloxy)methane, having a boiling range of 105-130~C/60 Torr and a pour point of -45~C, was prepared from bis(1,1-cyclohexyloxy)methane:
Ex. 34,perfluoro-bis(2,4-dichlorocyclohexyloxy)methane, having a boiling point of 150~C/40 Torr and a pour point of -25~C, was prepared from bis(2,4-dichlorophenoxy)-methane: and Ex. 35,[n-C4Fg(OC2F~)2O]2CF2, having a boiling point of 130-155~C/25 Torr, a pour point of -75~C, and a viscosity greater than 2000 cs at -85~C, was prepared from the corresponding hydrocarbon acetal.
Example 36 A mixture of 130.2 g (1.0 mol) isooctyl alcohol, g2 ml (1.05 mol) CH3OCH2OCH3, and 1 g p-toluenesulfonic acid was stirred at reflux for 18 hr. The internal temperature was now 60~C. Gas-liquid chromatography showed 30%
unreacted isooctyl alcohol, 41% presumed 1-isooctyloxy-1-methoxy methane, and 13%
bis(isooctyloxy)methane, the latter as three distinct peaks on the SE-52 chromatographic column. The reflux condenser was removed and the mixture was heated for 3 hr.
The temperature rose rapidly to 220 C. Gas-liquid chromatography now showed 13% isooctyl alcohol, 2%
1-isooctyloxy-1-methoxy methane, and 84~ bis(isooctyloxy)-methane. The p-toluene sulfonic acid was neutralized with Na2 C~3 and the filtered product was distilled to 102.3 g (75%) of pure bis(isooctyloxy)methane, bp 110-120~c/0.8 Torr.
Perfluoro-bis(isooctyloxy)methane, having a boiling ~"~ .

. ... ...

~3 lO29~

range o~ 120-140~C/60 Torr and a pour point of -40~C, was prepared from the above-prepared bis(isooctyloxy)methane using the fluorination technique of Example 32.
Example 37 In a 250 ml glass flask, a solution of 20.3 g (0.025 mol) bis(1,1-dihydropecfluorooctyloxy)methane (prepared from the alcohol by the method of Example using methylene chloride) in 80 mL Fluorinert FC-75 was treated with 8.0 g (0.154 mol) NaF. The mixture was flushed with nitrogen and chilled in an ice bath to 10~C. A slow feed (approximately 50-100 mL/min) of 9% fluorine in nitrogen was maintained over about 40 hr, using approximately 18 g fluorine. Gas-liquid chromatography and mass spectrometry showed two products in a 5:1 ratio, the larger being perfluoro-bis(perfluoro-octyloxy)methane (920 mol wt) and the smaller being monohydrido derivative(s) thereof.
Filtration and distillation gave a main cut of 10.2 g, bp 140-145 C/40 Torr, melting point -10 C. Gas-liquid chromatography showed two main isomers and a minor amount of the monohydrides. The total yield including other fractions was approximately 13g (56%).
Example 38 A mixture of 1645 g (13.9 mol) 2-butoxyethanol, 225 g (7.5 mol) paraformaldehyde, 2.0 g p-toluenesulfonic acid, and 1.5 liters toluene was stirred at reflux under a Dean-Stark trap, with steady evolution of water. After 16 hr, 10 g more paraformaldehyde was added and, at 18 hr, 20 g of 37~ formaldehyde was added, in attempts to force the reaction to completion. Conversion, as determined by gas-liquid chromatography was greater than 95~ and the mixture was cooled, washed with water containing a few grams NaOH, and the toluene allowed to evaporate. The residue was distilled, yielding 1430 g (83%) of bis(2-butoxyethoxy)methane, bp 100-110~C at 0.5 Torr.
Bis(2-butoxyethoxy)methane was also prepared from methylene chloride and 2-butoxyethanol as follows. A
mixture of 590.9 g (5.0 mol) 2-butoxyethanol, 1120 g (20 mol) KOH, 3 g AdogenT~ 464 quaternary ammonium salt, and 1 A ~

liter tetrahydrofuran was stirred for 30 min. The temperature rose to 45 C. -Careful addition of 750 ml (11.5 mol) methylene chloride and continued stirring at 55~C for 18 hr gave complete conversion of the alcohol to bis~2-butoxyethoxy)methane. The mixture was filtered with additional methylene chloride and distilled, yielding 552 g (96%) bis(2-butoxyethoxy)methane, bp 106~C/0.25 Torr, which is a product equivalent to that prepared above using formaldehyde as the source of the formal moiety, -OCH2O-.
A 600 mL Parr reactor of Monel~ metal was equipped with a 0.6 cm diameter Monel metal gas feed line (for premixed fluorine and nitrogen) with its outlet being about 2.5 cm from the bottom of the reactor, a 0.15 cm diameter nickel organic feed line with its outlet being about 7.5 cm below the top of the reactor, and a condenser cooled by the same bath as the jacket. The condenser was a 50 cm long straight double-tube construction, the inner tube having a diameter of about 1.2 cm and the outer tube having a diameter of about 2.5 cm. Gases from the reactor are cooled as they flow through the inner tube by ethylene-glycol-water flowing in the annulus between the tubes. This reactor was charged with 450 mL Freon 113 and 105 g (2.5 mol) NaF. The reactor was purged with nitrogen (175 mL/min) for 1 hr while stirring at 3~C. Fluorine was introduced into the nitrogen stream at 35 mL/min. After 15 min, a solution of 15.7 g (0.063 mol) of the above prepared bis(2-butoxyethoxy)methane diluted to 200 mL with Freon 113 was placed in a syringe pump and addition of the resulting solution was started at 9.2 mL/hr. The additions were maintained over the next 22 hr and after the organic addition was complete the fluorine addition was continued for 15 min more. The NaF and NaHF2 were filtered from the reaction product mixture, washed well with Freon 113, which was stripped at less than 25~C on a rotary evaporator, and the combined filtrate and washings were distilled, yielding 26.0 g (55%) of perfluoro-bis-(2-butoxyethoxy)methane, which was 95% pure as determined by gas-liquid chromatography. This perfluoroacetal product ~A~

..... . ....

- 82 - 13~0294 had a boillng range of 100-110 C/40 Torr, boiling po~nt of 183~C, pour point of -95~C, and viscosities of 147 cs, 504 cs, and 858 cs at -70 C, -80~C, and -85~C, respectively.
(In another run, the product had viscoSitieS of 117 cs and 690 cs at -70~C and -85~C, respectively). Traces of acid fluoride and hydrides (0.02 mg/g) were present (as found by infra-red and proton nuclear magnetic resonance analyses). The perfluoroacetal product was purified by stirring it with hot, aqueous KOH (25%) for 18 hrs, then washing the separated product with water and drying the washed product over silica gel. In another run, the distilled residue was purified by bubbling into it for 5 hrs at 175~C a mixture of fluorine diluted with nitrogen.
Both purification procedures gave colorless, odorless, thermally stable perfluoro-bis(2-butoxyethoxy)methane.
The thermal stability was determined by heating the purified product with aqueous sodium acetate for 22 hrs.
at 180~C in a closed, stainless steel tube and subsequently analyzing the aqueous layer for released fluoride ion, low fluoride ion content being indicative of thermal stability.
In a similar fluorination at -5~C (using a condenser temperature of about -5 C), bis(2-butoxyethoxy)methane precursor was fed into the reactor as an undiluted liquid to the mixture of NaF and Freon 113.
In another variation of the fluorination, the precursor diluted in Freon 113 was fed to a mixture of 15.7g NaF in Freon 113 and the fluorination carried out at -3~C with the condenser at -3 C (resulting in 51% yield).
In another variation of the fluorination, the precursor diluted in Freon 113 was fed to a mixture of NaF
and Freon 113 at -10 C (resulting in 42% yield compared to essentially no yield in a run when no NaF was used). In these runs, the condenser temperature was set at -25~C.
In another variation of the fluor-ination, the precursor was fed (diluted in Freon 113) to a mixture of Freon 113 and NaF at 18 C with the condenser set at -25~C
(resulting in 50% yield compared to a yield of 77% from a ,~-, - 83 - ~ 4~29~

run where no NaF was used). Another run without NaF at 0~C qave a 65% yield.
In another variation, the precursor was fed undiluted into Fluorinert FC-72 at 18 C (58% yield), and in another, fed diluted in Freon 113 into a slurry of NaF and Fluorinert FC-75 at 18 C and in another, fed diluted in Freon 113 into perfluoro-bis(2-butoxyethoxy)methane at 18~C. In these runs, the condenser was set at -25~C.
In another variation, the precursor was fed undiluted into Fluorinert FC-75 at 70 C tS5% yield) and in another run, fed undiluted into Fluorinert FC-87 at 20~C (42%
yield). In these runs, the condenser was set at about -25~C.
In another variation, the reactor was charged initially with 15.7 g bis(2-butoxyethoxy)methane, 105 g NaF, and 400 mL Freon 113 and cooled to -8~C with the condenser set at -8 C. A flow of 30 mL/min F2 and 120 mL/min N2 was continued for 20.5 hours. The c.ude product was isolated as above. H-nmr analysis showed the product contained 7.1 mg H/g liquid, corresponding to an average composition of C13H5F23O~. Gas-liquid chromatography showed little perfluoroacetal; instead the analysis revealed a series of many small peaks at retention times intermediate between those of the perfluoroacetal and the hydrocarbon acetal precursor. In a 200 mL vessel of Monel metal equipped with a water-cooled condenser, 25.0 g of the crude product was exposed to a gas flow of 20 mL/min F2 and 80 mL/min N2 for 0.5 hr at 50 C, then 2.6 hr at 100~C, 1.6 hr at 150 C, and 2.0 hr at 175 C. Distillation of the residue (16.4 g) yielded 12.7 g (41%) of perfluoro-bis-(2-butoxyethoxy)methane. H-nmr indicated it contained 0.3 mg H/g liquid.
Perfluoro-bis(2-butoXyethoxy)methane was also prepared by the solid fluorination technique of Example 32, the yield of the product being about 20%.
Example 39 A mixture of 150 g (1.5 mol) n-hexanol and 122 g (1.5 mol, 37%) formalin was treated with 140 g HCl gas over 3 .

., ~ ~029~
hr. The result~ng chloromethyl hexyl ether (172 g, 73%) was used directly. A mixture of 147.4 g (1.1 mol) 2-(2-ethoxyethoxy)ethanol, 130 g (1.3 mol), and 275 mL
acetonitrile was heated to 65 C and the above chloromethyl hexyl ether was added slowly, followed by refluxing overnight. Gas-liquid chromatography indicated 12%
unreacted RocH2cl and another 14 g of the alcohol was added. After an additional hour, the mixture was cooled, washed with water, and the product was dried in methylene chloride over Mg2SO~ and distilled to 205.6 g (75%) 3,6,9,11-tetraoxaheptadecane, bp 126~C/0.5 Torr.
The tetraoxaheptadecane, prepared as described above, was fluorinated by the liquids fluorination technique of Example 7 at about -5~C in the pcesence of NaF to produce C6Fl3OCF2O(C2F~O)2C2Fs, which had a boiling range of 75-88~C/11 Torr, boiling point of 170~C, viscosities at -70~C
and -85~C of 237 cs and >2500 cs, respectively, and pour point of -80~C.
Examples 40-58 Using the liquids fluorination technique of Example 38 at about -5~C in the presence of NaF, different perfluoroacetal compositions, each containing a single perfluoroacetal compound listed below (except as indicated) together with properties of the composition, were prepared from corresponding precursor acetals (made by the routes illustrated by Equations 1, 2, or 3 or by Equations 4 and 5, supra) which were saturated except as noted.
3 (CF2)3OCF2O(C2F~O) 2 ( C~2 ) 3CF3, boiling range of 100-120 C/46 Torr, boiling point of 173 C, pour point of -90~C, and viscosities at -70~C and -85~C of 148 cs and >2000 cs, respectively.
41- (cyclo-C6Fl1O)2CF2,- boiling range of 100-120 C/20 Torr, pour point of -60~C, made from diphenoxymethane.

, 1 ~ 4 !~ 2 9 4 42. (cyclo-C6FllCF~O)2CF2, boiling range of 95-115 C/10 Torr, pour point of -60~C, and viscosity at -70~C of >2000 cs, ~ade from dibenzyloxymethane [CF3 (CF2 )2 ~OC2F~)3O]2CF2, boiling range of 110-125~C/8 Torr.
44. [CF3 (O-isoC3 F6)2O]2CF2, boiling at 120 C/35 Torr, pour point of -75~C, and viscosity of 1111 cs at _70~C.
45. (ClC2F4OC2F~O)2CF2, boiling range of 155-170~C/740 Torr, and viscosities of 55 cs and 398 cs at -70~C
and -85~C, respectively.
46.... [C2F5(OC2F~)2O]2CF2, boiling range of 100-110~C/60 Torr, boiling point of 176 C, pour point of -8S C, and viscosities of 106 cs, 469 cs, and 1531 cs at -70~C, -80~C, and -85~C, respectively.
lCF3 (CF2 )2 (OC2F~)2Ol2CF2, boiling at 120~C/35 Torr pour point of -85 C, and viscosities of 429 cs and >2000 cs at -70~C and -85~C, respectively.
48. 3 ~C2 F~ ~CF2 ( ~C2 F~ ) 3 OCF2 ~C2 F4 OCF3, boiling at 115~C/30 Torr, pour point of -95 C, and viscosities of 162 cs and 1500 cs at -70~C and -85~C, respectively.
3 C2 F~ ~CF2 ~ ( C2 F~ ~ ) 2 ( CF2 ) 3 CF3, boiling at 90~C/40 Torr, pour point of -85~C.
C F Oc2F~ocF2(oc2F4)3ocF2oc2F~oc2F5l boil g 120-140~C/40 Torr.
51. 2 5 OC2 F~ OCF2 ( OC2 F4 ) 2 OCF2 OC2 F4 OC2 F5 ~ boiling range of 90-110~C/15 Torr, boiling at 190~C/740 Torr, and viscosities of 274 cs and 2375 cs at -70~C and -85~C, .

- 86 - ~ q~ ~02 respectively.
52. CF3(CF2)3(OC2F~)~OCF~OC2F5, boiling range of 70-90~C/lS Torr, boiling point of 165~C, and viscosities of 120 cs and 750 cs at -70~C and -85~C, respectively.
53. (n-C~Fl~O)2CF2, boiling range of 125-140~C/24 Torr, boiling point of 211 C, and melting point of -50~C.
54. [(CF3 )2CFCF2OC2F4O]2CF2, boiling range of 70-110~C/25 Torr, and viscosities of 240 cs and 1015 cs at -70~C
and -80~C, respectively.
55. [(CF3 )3COC2F4Ol2CF2, boiling range of 80-88 C/17 Torr, boiling point of 183~C, and pour point of -80~C, and viscosity of 2600 cs at -70~C.
56. [CF3 (CF2)3OC2F4O]2CFCF3, boiling range of 85-95~C/40 Torr, and viscosities of 180 cs and 2504 cs at -70~C
and -80~C, respectively.
57. An approximately equimolar mixture of ( C2 F5 ~C2 F~ ~C2 F, ~ )2 CF2 and (C~ Fg ~C2 F4 ~ )2 CF2, made by fluorinat-on of a mixture of 11.2g and 10.0g of the respective hydrocarbon precursors, boiling at 178~C
and having a viscosity of 104 cs and 395 cs at -70~C
and -80~C, respectively.
58. A ternary mixture of approximately one part (C2F5OC2F4OC2F4O)2CF2, one part (C4FgOC2F4O)2CF2l and two parts C4 Fg ~C2 F4 OCF2 ~C2 F4 ~C2 F4 ~C2 F5 ~ made by fluorination of the reaction product of an equimolar mixture of C2 Hs ~C2 H4 ~C2 H4 OH and C4 Hg ~C2 H4 OH wi th formaldehyde, said fluorinated mixture boiling at 179~C and having viscosities of 87 cs and 340 cs at -70~C and -80~C, respectively.
;, j

Claims (56)

1. A perhalogenated polyether consisting essentially of:

wherein R1, R2, R3, R4, R5 and R6 are the same or different and are selected from the group consisting of -F, -Cl, -CF2Cl, -CFCl2, -CCl3, perfluoroalkyl of one to ten carbon atoms, perfluoroalkoxyalkyl of one to ten carbon atoms and perfluoroalkoxyether of one to ten carbon atoms wherein one or more of the fluorine atoms can be substituted by a halogen atom other than fluorine; X and Z are the same or different and are selected from the group consisting of -(CF2)r COF, -(CF2)r OCF3, -(CF2)r COOH and -C r F2r+1-q Cl q, wherein r is an integer from 1 to 12 and q is an integer from 0 to 25; n is an integer from 2 to 1,000; m is an integer from 0 to 1000; p and t are the same or different and are integers from 1 to 50, provided that when p and t are one and R1, R2, R3 and R4 together are F, then R5 or R6 is a group other than fluorine.

2. The perhalogenated polyether of claim 1 wherein m is zero; R1, R2, and R5 are F and p is an integer between 2 and 50.

3. A perhalogenated polyether consisting essentially of:

wherein X and Z are the same or different and are selected from the group consisting of -(CF2)r COF, -(CF2)r OCF3, -(CF2)r COOH and -C r F2r+1-q Cl q, wherein r is an integer from 1 to 12 and q is an integer from 0 to 25; wherein R1 and R2 are the same or different and are selected from the group consisting of -F, -Cl, -CF2Cl, -CFCl2, -CCl3, perfluoroalkyl of one to ten carbon atoms, perfluoroalkoxyalkyl of one to ten carbon atoms and perfluoroalkoxyether of one to ten carbon atoms wherein one or more of the fluorine atoms can be substituted by a halogen atom other than fluorine, provided that R1 and R2 together are not F;
wherein n is an integer from 2 to 1,000.

4. A perhalogenated polyether of claim 3, wherein R1 is F, R2 is -CF2Cl and n is greater than 20.

5. A perfluorinated polyether consisting essentially of:
Y-O-CF2-O-Y' wherein Y and Y' are the same or different and are selected from the group consisting of perfluoroalkyl of one to ten carbon atoms, perfluoroalkoxyalkyl of one to ten carbon atoms, perfluoroalkyleneoxyalkyl of one to ten carbon atoms and perfluoroalkoxyether of one to ten carbon atoms; wherein one or more of the fluorine atoms can be substituted by a halogen atom other than fluorine and wherein the polyether comprises less than 8 or at least 12 carbon atoms provided that Y and Y' cannot both be -CF3 or -C2F5.

6. The perfluorinated polyether of claim 5, wherein the polyether comprises from 12 to 20 carbon atoms.

7. A perhalogenated polyether consisting essentially of:

wherein Y and Y' are the same or different and are selected from the group consisting of perfluoroalkyl, perfluoroalkoxyalkyl and perfluoroalkyleneoxyalkyl;
wherein R1 and R2 are the same or different and are selected from the group consisting of -Cl, -CF2Cl, -CFCl2, -CCl3, perfluoroalkyl having one to twenty carbon atoms, perfluoroalkyleneoxyalkyl of one to ten carbon atoms and perfluoroalkoxy of one to ten carbon atoms wherein one or more of the fluorine atoms can be substituted by a halogen atom other than fluorine;
and wherein the polyether comprises at least 12 carbon atoms.

8. The polyether of claim 7 wherein the polyether comprises 12 to 25 carbon atoms.

9. A perhalogenated polyether consisting essentially of:

wherein Y and Y' are the same or different and are selected from the group consisting of perfluoroalkyl, perfluoroalkoxyalkyl and perfluoroalkyleneoxyalkyl, each having 1 to 50 carbon atoms; R is selected from the group consisting of -Cl, -CF2Cl, -CFCl2, -CCl3, perfluoroalkyl of one to twenty carbon atoms, perfluoroalkyleneoxyalkyl of one to ten carbon atoms and perfluoroalkoxyether of one to ten carbon atoms wherein one or more of the fluorine atoms may be substituted by a halogen atom other than fluorine;
and wherein the polyether comprises at least 12 carbon atoms.

10. The polyether of claim 9 wherein the polyether comprises from 12 to 25 carbon atoms.

11. A perhalogenated polyether consisting essentially of:

wherein Y and Y' are the same or different and are selected from the group consisting of perfluoroalkyl, perfluoroalkyleneoxyalkyl and perfluoropoly(alkyleneoxy)alkyl, each having 1 to 50 carbon atoms, wherein one or more of the fluorine atoms can be halogen atoms other than fluorine; wherein R1 and R2 are the same or different and are selected from the group consisting of -F, -Cl, -CF2Cl, -CFCl2, -CCl3, perfluoroalkyl having 1 to 20 carbon atoms, perfluoroalkoxyalkyl of one to ten carbon atoms and perfluoroalkoxy of one to ten carbon atoms wherein one or more of the fluorine atoms can be substituted by a halogen atom other than fluorine.

12. The polyether of claim 11 wherein R1 and R2 are fluorine.

13. The polyether of claim 11 wherein R1 is fluorine and R2 is perfluoromethyl.

14. A method of preparing a perhalogenated polyether consisting essentially of:

wherein X and Z are the same or different and are selected from the group consisting of -(CF2)r COF, -(CF2)r OCF3, -(CF2)r COOH and -C r F2r+1-q Cl q, wherein r is an integer from 1 to 12 and q is an integer from 0 to 25; wherein R1 and R2 are the same or different and are selected from the group consisting of -F, -Cl, -CF2Cl, -CFCl2, -CCl3, perfluoroalkyl of one to ten carbon atoms, perfluoroalkoxyalkyl of one to ten carbon atoms and perfluoroalkoxyether of one to ten carbon atoms wherein one or more of the fluorine atoms can be substituted by a halogen atom other than fluorine provided that R1 and R2 together are not F;
wherein n is an integer from 2 to 1,000; comprising the steps of:
a) placing a polyether hydrocarbon analog of the above formula into a fluorine reactor;
b) fluorinating the polyether hydrocarbon analog by establishing a flow of gas mixture of fluorine gas and an inert gas into the reactor under conditions sufficient for perfluorination of the polyether; and c) after the fluorination reaction is completed to a desired degree, removing the perfluorinated polyether from the reactor.

15. The method of claim 14 wherein the reactor is a stationary metal tube, rotating drum reactor fluidized bed reactor, or solvent reactor.

16. The method of claim 14 wherein the polyether is mixed with a hydrogen fluoride scavenger or coated on the hydrogen fluoride scavenger, the amount of the hydrogen fluoride scavenger in relation to the amount of polyether being sufficient to react with most of the hydrogen fluoride formed during fluorination.

17. The method of claim 16 wherein the hydrogen fluoride scavenger is sodium fluoride or potassium fluoride.

18. A method of preparing a perhalogenated polyether consisting essentially of:

wherein Y and Y' are the same or different and are selected from the group consisting of perfluoroalkyl, perfluoroalkylether and perfluoroalkylpolyether, each having 1 to 50 carbon atoms, wherein fluorine can be substituted with one or more halogen groups other than fluorine, wherein one or more of the fluorine atoms can be halogen atoms other than fluorine;
wherein R1 and R2 are the same or different and are selected from the group consisting of -F, -Cl, -CF2Cl, -CFCl2, -CCl3, perfluoroalkyl of one to ten carbon atoms, perfluoroalkoxyalkyl of one to ten carbon atoms and perfluoroalkoxyether of one to ten carbon atoms wherein one or more of the fluorine atoms may be substituted by a halogen atom other than fluorine; and comprising the steps of:
a) placing a polyether hydrocarbon analog of the above formula into a fluorine reactor;
b) fluorinating the polyether by establishing a flow of gas mixture of fluorine gas and an inert gas into the reactor under conditions sufficient for perfluorination of the polyether; and c) after the fluorination reaction is completed to a desired degree, removing the perfluorinated polyether from the reactor.

19. The method of claim 18 wherein the reactor is a stationary metal tube, rotating drum reactor, fluidized bed reactor, or solvent reactor.

20. The method of claim 18 wherein the polyether is mixed with a hydrogen fluoride scavenger or coated on the hydrogen fluoride scavenger, the amount of the hydrogen fluoride scavenger in relation to the hydrogen fluoride scavenger in relation to the amount of polyether being sufficient to react with most of the hydrogen fluoride formed during fluorination.

21. The method of claim 20 wherein the hydrogen fluoride scavenger is sodium fluoride or potassium fluoride.

22. A perfluorinated gem-alkylenedioxy composition which is normally liquid and consists or consists essentially of a perfluorinated gem-alkylenedioxy compound, where said alkylene is (a) bis(trifluoromethyl)methylene and said compound has at least 12 carbon atoms, (b) perfluoroalkylene-substituted fluoromethylene and said compound has at least 6 carbon atoms, (c) difluoromethylene and said compound has at least 6 carbon atoms, or (d) any of (a), (b), and (c) wherein one or more of the fluorine atoms of said compound may be chlorine atoms, and wherein said compound may contain one or more further ether oxygen atoms.

23. A composition of Claim 22, wherein said compound can have two perfluoro-1,1-alkylenedioxy moieties provided such moieties are separated from each other by at least two catenary carbon atoms of a perfluoroalkylene moiety.

24. The composition of Claim 23 consisting or consisting essentially of one of said compounds.

25. The composition of Claim 23 consisting or consisting essentially of a mixture of said compounds.

26. The composition of Claim 23 wherein each saturated perfluoro-1,1-bis(alkoxy)alkane compound is represented by the formula:

wherein R1f and R5f are each independently selected from the group of C1 to C8 linear or branched perfluoroalkyl, C1 to C8 linear or branched chloroperfluoroalkyl, and unsubstituted or lower alkyl-substituted perfluorocycloalkyl or chloroperfluorocycloalkyl wherein the number of ring carbon atoms is 4 to 6; R2f, R3f, and R4f are each independently selected from the group consisting of C2 to C4 linear or branched perfluoroalkylene and C2 to C4 linear or branched chloroperfluoroalkylene;
each R6f is independently a fluorine atom or perfluoroalkyl with 1 to 4 carbon atoms and wherein the compound optionally includes one or more chlorine atoms; x and w are each independently an integer of 0 to 4; y is an integer of 1 to 6; z is an interger of 0 or 1; and where the total number of carbon atoms in said compound is 6 to 30.

27. The composition of claim 26, wherein each R6f is independently F or CF3 and the total number of carbon atoms in said compound is 12 to 17.

28. The composition of claim 23 wherein each saturated perfluoro-1,1-bis(alkoxy)alkane compound is represented by the formula:

C n F2n+1(OC m F2m)a-OCF[(CF2)p F]O-(C m'F2m'O)b C n'F2n'+1 wherein each n and n' is independently an integer of 1 to 6, each m and m' is independently an integer of 2 to 4, a and b are each independently an integer of 0 to 4, and p is 0 or 1, each said compound having 13 or 14 total carbon atoms, said composition having a viscosity at -70°C of less than about 300 centistokes.

29. The composition of Claim 26 wherein said compound is perfluoro-bis(2-butoxyethoxy)methane.

30. The composition of Claim 26 wherein said compound is perfluoro-3,6,9,11-tetraoxaheptadecane.

31. The composition of Claim 26 wherein said compound is perfluoro-5,7,10,13-tetraoxaheptadecane.

32. The composition of Claim 26 wherein said compound is perfluoro-2,14-dimethyl-4,7,9,12-tetraoxapentadecane

33. The composition of Claim 26 wherein said compound is perfluoro-3,6,9,11,14,17-hexaoxanonadecane.

34. The composition of Claim 26 wherein said compound is perfluoro-2,5,7,10,13,16,18,21-octaoxadocosane.

35. The composition of Claim 26 wherein said compound is perfluoro-3,6,8,11,14,16,19-heptaoxaheneicosane.

36. The composition of Claim 26 wherein said compound is perfluoro-3,5,8,11,14-pentaoxaoctadecane.

37. The composition of Claim 25 consisting or consisting essentially of a mixture of perfluoro-bis(2-butoxy-ethoxy)methane, perfluoro-3,6,9,11,14,17-hexaoxanon-adecane, and, optionally, perfluoro-3,6,9,11,14-pentaoxaoctadecane.

38. The composition of Claim 22 wherein said compound is represented by the formula:

CF3CF2CF2CF2OCF2CF2OCF2CF2OCF2OCF2CF2OCF2CF2OCF2CF2CF2CF3.

39. The composition of Claim 22 wherein said compound is represented by the formula:

CF3CF2OCF2CF2OCF2CF2OCF2CF2OCF2OCF2CF2OCF2CF2OCF2CF2OCF2CF3.

40. The composiiton of Claim 22 wherein said compound is represented by the formula:

OCF2CF2OCF2CF2CF2CF3.

41. The composition of Claim 22 wherein said compound is represented by the formula:

OCF2CF2OCF2CF2OCF2CF2OCF2CF2CF2CF3.

42. The composition of Claim 22 wherein said compound is represented by the formula:

CF3O(iso-C3F6O)3CF2(O-iso-C3F6)3OCF3.

43. The composition of Claim 22 wherein said compound is represented by the formula:

CF3CF2O(CF2CF2O)3CF(CF3)O(CF2CF2O)2CF(CF3)-(CF2CF2O)3CF2CF3.

44. The composition of Claim 22 wherein said compound is represented by the formula:
CF3CF2OCF2CF2OCF2CF2OCF2CF2OCF(CF3)OCF2CF2-CF2CF2OCF2CF2OCF2CF3.

45. The composition of Claim 22 wherein said compound is represented by the formula:

CF3-iso-C3F6O-iso-C3F6O-OCF(CF3)O-iso-C3F6O-iso-C3F6OCF3.

46. The composition of Claim 22 wherein said compound is represented by the formula:

CF3CF2CF2CF2OCF2CF2OCF2CF2OCF(CF2Cl)OCF2CF2OCF2CF2O-CF2CF2CF2CF3.

47. The composition of Claim 22 wherein said compound is represented by the formula:

.

48. The composition of Claim 22 wherein said compound is represented by the formula:

(ClCF2)2CFOCF2OCF(CF2Cl)2.

49. The composition of Claim 22 wherein said compound is represented by the formula:
.

50. The composition of Claim 22 wherein said compound is represented by the formula:

.

51. The composition of Claim 22 wherein said compound is represented by the formula:

.

52. A process for making the composition of Claim 23, which comprises contacting the corresponding perfluorinateable, fluorine-free or partially-fluorinated precursor acetal with a stoichiometric excess of fluorine gas to essentially perfluorinate the same.

53. The process of Claim 52 wherein said contacting is carried out in the presence of a hydrogen fluoride scavenger.

54. A method of transferring heat from an article to a cooling liquid comprising at least partially immersing the article into a liquid cooling bath, wherein the cooling bath comprises the composition of Claim 22, for a period of time sufficient to cool the article.

55. A method of inducing thermal shock of an article comprising:
a. heating a first bath of a heating liquid to a temperature above ambient temperature;
b. cooling a second bath of a cooling liquid to a temperature below ambient temperature; and c. sequentially:
i. immersing the article in an initial bath which is one of said first and second baths and allowing said articles to come to the temperature of said initial bath before removing said article from said initial bath, and ii. then immersing said article in the other of said first and second baths and allowing said article to come to the temperature of said other bath before removing said article from said other bath;
wherein said liquids are inert, thermally stable, perfluorinated liquids, at least one of which is the composition of Claim 23.

56. A method in accordance with Claim 55, wherein said heating and cooling liquids are identical and are saturated perfluoro-1,1-bis(alkoxy)alkane compounds.