CA1041694A - Linear, thermoplastic polyesters - Google Patents

Abstract

NEW, LINEAR, THERMOPLASTIC POLYESTERS
Abstract of the Disclosure Linear polyesters based on terephthalic acid and/or isophthalic acid and containing di-(hydroxyalkyl) compounds of oligomeric N,N-heterocyclic compounds as the diol component, have higher glass transition temperatures compared with poly-(alkylene) terephthalates. The new polyesters are thermoplastic materials suitable for the manufacture, by customary moulding processes, of mouldings having a higher heat distortion point.

Description

~! ~
. ~ . . ..

~ ' . ':
i me present invention relates to new, linear polyesters ': !, ~: :
based on terephthalic acid and/or isophthalic acid and contain- -; ing di-(hydroxyalkyl) compounds of oligomeric N,N-hetero-cyclic compounds as the diol component, a process for the manu~
facture of the new polyesters and the use of these polyesters, which are valuable thermoplastic materials.
ermoplastic polyesters based on tereph-thalic acid or $ ~
isophthalic acid and aliphatic diolst such as, for example, polye-thylene terephthalates and polybu-tylene terephthalates, are known. Fur-t~ermore, the use of these polyesters for the `~
manufacture of mouldings having good mechanical properties or ; ~-`
for the coating of objects, for example for insulating purposes, is known. However, the articles manufactured from these poly-esters also have disadvantages, particularly in their thermo mechanical properties. Thus, the glass transitio~ point of `-~
these polyesters is generally relatively low, which is found to be a disadvantage in many industrial applications, because -the ;--mouldings lose their rigidity even at relatively low tempera~
tures. ~ A further disadvantage of the known polyethylene terephthalates and polybutylene terephthalates consists of the , . . . . .
fac-t that fairly high temperatures must he used in their ~;
processing.

,.', - ~,', :, . i -, .

~ `

German Offenlegungsschrift DT 2,00~,984 discloses that ~
the properties of polyethylene -terephthalates and polybutylene ~ ;
terephthalates can be improved by co-condensing dispiro-(5.1.5.1.)-tetradecane-7,14-diol into the polyester, 15 - 50%
of the ethylene glycol or propylene glycol being replaced by ~`-this special, expensive, tricyclic diol.
It has now been found -that polyesters composed of terephthalic acid and/or isophthalic acid and aliphatic diols with improved properties can also be obtained by the co-condensation of oligomeric di-(hydroxyalkyl) compounds contain-ing more than -two N,N-heterocyclic rings) which can be prepared cheaply. It is surprising that the improvement of the pro- ;`;~
perties of these polyesters is achieved by means of compounds which con-tain hydroxyethyl groups and in which the N,N hetero~
eyclic rings are linked via me-thylene groups and/or, if approp-:.i . ~:
J riate, also via substituted e-thylene groups, since it is known `~ ;
¦ ~ that, owing to the powers of free rotation of these groups, they - do not-bring rigidity into the molecule. It is also surprising that the degree of improvement in the properties which can be ~3 achieved is higher the more N,N-heterocyclic rings the di~
., :;
~hydroxyalkyl) compounds according to the invention contain.
In addition, excellent properties are displayed even by poly~
esters which are synthesised only from terephthalic acid and/or ~ -isophthalic acid and the heterocyclic diol. In the following :-~
text polyesters are understood as all polymers consisting of `
either one acid and one diol component or two acid components and one diol component or one acid component and two diol com-i ponents. In addition, the term polyester also comprises .. ~ . .

.', '"
,,"

! polymers synthesised from two acid components and two diol components. --Compared with the polyalkylene terephthalates, the polyesters according to the invention are distinguished by higher glass transition temperatures and, at the same time, low ` melting poin-ts or softening poin-ts; thus -they display be-tter `~
thermo-mechanical properties and can be processed more easily.
The present invention therefore relates to new, linear, ;
thermoplastic polyesters having a relative viscosity of 0.5 to 4.0, measured at 30C on a 1% strength solution consisting of ~, equal parts of phenol and tetrachloroethane, which are charac-- terised by the general formula I

~3-o-E-o~ C-0-CH-(I~ U2-A-Ul-A-U2 CH- r wherein the carbonyl groups can be linked to the aromatic rings ;~
in the meta- or para-position or can be linked to different ~ -aromatic rings in the meta- and para-posi-tion, E represents an aliphatic radical with 2 to 10 carbon atoms which is linear or ` is branched by means of the methyl or ethyl group, or represents ;~ -~i the 1,4-dimethylenecyclohexane radical, Rl denotes in each case a hydro~en atom or the methyl, ethyl or phenyl group, and R2 denotes a hydrogen atom or~ conjointly wi-th Rl, denotes the tetramethylene radical, A denotes a radical o~ the formulae -CH2-, -CH2-CH2-; -CH2-CH-, -CH2-CH- , -CH-CH\ or --CH2-; - 3 ~ ~
':' '.
:' .;
:., ,, , ; - , ... , . .. ... : , .. ,, , ~
.... . . . . .

~o~
U.l denotes a radical o~ the formulae .-Q ~ or C ~ C / -N ~N-.. . ~.;
;"1 ' . , ~ B~ / 1 B~ ~ / ~;

`: N / N - CH2 ~ N\ N- -~

~ ~herein B1 and B2 independently of one another each denote a ~...
~3 . hydrogen atom or an alkyl radical wi-th 1 to 4 carbon atoms, and .
;~ U2 has the same meaning as Ul or denotes a radical of the for- .: :
;.~ mula `
D2 C~ -`
'', C I . ,~
.1 -N N-'" \C~ . :

:J wherein Dl and D2 independently of one another each denote a ~r,~ `, 1 - hydrogen atom, an alkyl radical with 1 to 4 carbon atoms or the phenyl radical or, conjointly, denote the pentamethylene radi-cal, m represents 0 or integers and n represents integers, it .. 1 ~
., being possible for the mol fraction n n m derived from n and m ~ to assume values from 0.02 to 1. ~ ~.
~ 1 '. .
:3 Preferably, the polyesters with the structural element .. ,.' ... . . .
~ 4 ~
.. ', . . . . .
. :. , ,.. ~' '',' . '' ', ' .`:`" '`

' of the formula I have a relative viscosity of 1.0 -to 3.0, the carbonyl groups are linked to the aromatic rings in the meta- ~
or para-position or are linked to different aromatic rings in ~:
~: the meta- and para-position, E denotes an alipha-tic radical .
with 2 to 4 carbon atoms, Rl and R2 each denote a hydrogen --~ atom, A denotes-the methylene or ethylene radical, U1 denotes :~:
:~1 a radical of -the formulae ~ Q ~ CH~ C1~3 C\3 / 3 , ~N ~N-, N~ ~N- or~ N\ ~N - CH2 ~

and U2 denotes a radical of the formuia ;~

`~ f ~:~ N f ~
!.'.' . ...

! wherein Dl and D2 represent the methyl group or, conjoin-tly, . -:.~ represent the pen-tamethylene radical, and the mol fraction ~ n n m has values from 0.05 to 1.
.,~ . . ~
:~ m e new polyesters with the structural element of the .~
;. . .:
. formula I are obtained by known processes, by polycondensing ..
j n mols9or ~ appropriate n~m mols, of terephthalic acid, iso- :
:~ . .
phthalic acid or polyester-forming deriva-tives thereof with :
5 _ ' ~

:, .

.~ n mols of a diol of the formula II
:i : ~
H-CH-CH-U2-A-Ul-A-U2-CH-fH-H (II) 1 R2 R2 Rl :
-~ wherein Rl, R2, A, Ul and U2 have the same meaning as in for-.`~ mula I, if appropriate mixed with m mols of a diol of;~
the formula III
HO - E - OH (III) wherein E has -the same meaning as in formula I, corresponding :; to the mol fraction n n m = 0.02 to 1.0, and in the presence of catalysts, in a known manner to give a relative viscosi-ty of `~
0.5 to 4Ø
Terephthalic acid, isophthalic acid or polyester-,. .; ,, forming derivatives thereof are preferably polycondensed in a molar ra-tio corresponding to the Inol fraction n n m = 0 05 -to 1.0, to give a relative viscosity of 1.0 to 3Ø :~
Examples of the known processes ~or the preparation of the new polyesters are solution condensation or azeotropic-con~
densation, interfac~ condensation, melt condensation or solid phase eondensation as well as a combination of these methods, ..
depending on which polyester-forming derivatives and reaction catalysts are used~
me polyester-~orming derivatives of terephthalie acid and isophthalic acid used are principally the low molecular dialkyl esters with 1 to 4 carbon atoms in the molecule, pre -ferably dimethyl es-ters or diphenyl esters. In addition, the .--.:
aeid dihalides, especially the aeid dichlorides, and polyanhyd~
rides of terephthalic acid or isophthalic acid as well as mixed ;;;
anhydrides of these aeids and low molecular aliphatic mono- .

. ,, ~: :
'~1 .....
"t, ., ~,, ., ' ,.~
., , carboxylic acids are also suitable.
The known aliphatic diols wi-th 2 to 10 carbon a-toms -which are linear or are branched by means of a methyl or ethyl .
- group, and 1~4-dihydroxymethylcyclohexane are represented by ;
. means of the formula III.
The diols of the formula II are new compounds which are `-, . . .
I obtained according to aprocess describedin German Offenlegungs-schrift 2,003,016, according to the following schedule of reac-tions~
~, 1 mol of the known compound of the formula IV
H - Ul - H (IV) ~i is condensed with 2 mols of the known monohalogen compound OI ..
I the formula V
:~ H - U2 A - Hal (V) `~ wherein "Hal" represents a halogen atom, at tempera-tures bet~
ween 20 and 200C in a suitable solvent, for example water or dioxane, and in the presence of a base, for example NaOH or ;~ pyridine, with the elimination of 2 mols of hydrogen halide. ~:
In a ~ariant of the process, 1 mol of a dihalogen compound of -~ the formula VI :~
:~l HaI - A - Ul - A - Hal (VI) ' f iS reacted with 2 mols of a compound of the formula VII
H - U2 - H (VII) ~
with the eli.mination of 2 mols of hydrogen halide. . ~`
~ 1 mol of the new compounds of the general formula VIII
,l H - U2 - A - Ul - A ~ U2 ~ (VIII) `~
. ~; . .... .
prepared by these processes, is reacted, by an addition reaction with 2 mols of an alkylene oxide o~ the formula IX
.. ~ .
~ , _ -,,, . ' .
, .

~H - CH (IX) ~: 1 2 -"

in the presence of an acid or basic catalyst, for example AlC13 ..
.~ - or triethylamine, and at temperatures between 0 and 200C, to `.
~ give the diols of the formula II. In the preceding reaction .~ schedule, Ul, U2, ~, Rl and R2 have the same meaning as in :~' formula I.
Compounds corresponding to the formula IX are, in ;~
addition to ethylene oxide, propylene oxide, butylene oxide, styrene oxide and cyclohexylene oxide.
~; The following are examples of diols of the formula II~

H-~2-C~2 N N-C112 N N-SU2-N N-CH2-CH2-OH

~Z

.; -- ~- ~ ,, ! ` `~

:`, , `.'::.-. j . - . :

\C/ 3 C~ ~\N \3 1~0 IH-CH2-N~ ~ 2 \~ i C2 : ' . . . . `.~ ., :

~ C~ ~C2H5 ~0 , , , B~ CH CH I I-CH-CH2-; N- C~l N ~N-~ 2-CH2-~

2Hs s~ ' ~ C c - . ~

\C/ \C/

.
.3 HO'C11~1 2-Cj -N ll-H-C112 N ~1 ISl-Otl ~ ~

.! . ~;; ::

g .: ' ..

. .

,:, ., , ~ ' , The following ~re ~xamples of possible preferred diols of the formula II:

.j ~ .
.

o ~
., , , ~ .. , t N ~ ~ ~ :
, a \ ~ ~ ~ 1 x ,. ~, ~
`' ~ Z ~ Z ~`': : -// i~ ~ ~ '` `~''' 3~ ~ z ~ ~ z `~

~ ~\i / = a\ i / =
'3~ a a a a ~:
Z ~_ Z

I_Z/ I Z/
, ~ ? .:
~, 0~ X o ~ 3~ ,, - . ~ ' J~ J ~=o j ~=o ~ :
Z ~ Z

' - ~N
:~ o o ;' . ' ~:

iJ
`'' '' ~ ` ~`:

,', q ~3 :. . . . ..
~\ T~ ~ ~

o~ T-~`= ``~

. C....... - i O ~-Z\ ' ~

' '` ' ~ :~

,~

` .
.,,, ~ .

; In particular, -the mol fraction derived from n and m in formula I is 0.2 -to 1 for the preferred diols. .
The new polyesters can be prepared by esterifying or ~ transesterifying at 150 - 250C terephthalic acid7 isophthalic ~-j acid or low molecular dialkyl esters thereof with -the diols of the formula II, preferably mixed with the diols of the formula -~
III, in an inert atmosphere, for example a nitrogen atmosphere, "
in the presence of catalysts and with simultaneous removal of ~-:
~ the water or alkanol formed, and by subsequently carrying out ~-`.~ the polycondensation at 200 - 270C and under reduced pressure ~ ` in the presence of certain catalysts, until the polycondensates .... .. ~ .
have the desired viscosi-ty. ~
In the preparation of polyesters which also contain, ` ; i -besides a diol according to the invention, compounds of the formula III as the aliphatic diol component, this diol co~po-3i nent is advantageously used in excess, so that, after the esterification or transesterification reaction, essentially monomeric diglycol esters of both diols of the formulae II and `
'i ~
III are obtained, which are then polycondensed in -the presence .`
i~ of a polycondensation catalyst and with the removal by distil~
., i . .
lation in vacuo of the excess aliphatic diol of the formula III. ^~
Amines, inorganic or organic acids, for example hydro- ` ~`
-chloric acid or p-toluenesulphonic acid, or else metal compounds, -~ -` which are also suitable as transesterification catalysts, can i be used in a known manner as the esterification catalysts.
, Since some catalysts preferen-tially accelerate the , transesterification and others preferentially accelera-te the :, polycondensa-tion, it is advantageous to use a combination of ; - 12 -, , '':
.sl : . :
, - ~
- .:

several ca-talysts. Examples of suitable transesterification -catalysts are the oxides, salts or organic compounds of the : -metals calcium, magnesium, zinc9 cadmium, manganese, titanium and cobalt. The metals as such can also be used as catalysts.
The polycondensa-tion is catalysed, for example, by me-tals such . , . . ~ ~ !
as lead, titanium, germanium and, in particular, an-timony or --compounds thereof. These catalysts can be added to the reac~
~ tion mixture together or separately. These catalysts are .`3 . employed in quantities of about 0.001 to 1.0 per cent by weight, :; , ;~ relative to the acid component. - -~
:.1 -. :: .
In the preparation of the new polyesters it is particu~
~; larly advantageous to use those ca-talysts which accelerate both , :"
the transes-terification and the polycondensation. Possible catalys-ts of this kind are above all mixtures of various metals or metal compounds as well as corresponding metal alloys It is also possible to carry out the polycondensation in such a way tha-t the starting compounds are first condensed, J ln the melt, to give a certain viscosity, the precondensate thus ~ prepared is then granulated, for example with the aid of an `~ underwater granulator, and the granules are dried and then sub-jected -to a solid phase condensation, a vacuum and temperatures ¦ below the melting point of the granules being used. In this -,~ , :
way higher viscosities can be achieved in the polyesters.
The polycondensation reaction is carried out until -the polyesters have a relative viscosity of 0~5 to 4.0, preferably l,O to 3Ø The reaction times are about 30 minu-tes to several hours, depending on the nature of -the catalyst used and the size of the batch. A~ter being removed from the reaction ~ ~-. .

, ~;
. ,~ ., .
.,' ' ' '`~ ' ,' ' ' ~
.. ~ .

vessel and cooled in the usual way, the resul-ting polyester - melts are granula-ted or chipped.
Another process for the prepara-ti.on of the new poly- ;
esters consis-ts of polycondensing terephthalic acid dihalides `~
~ and/or isophthalic acid dihalides, preferably the acid dichlor- ~
ides, with the diols of the formula II, op-tionally mixed with ~ -the diols of the formula III, in -the presence of a basic cata-lyst in the temperature range from 0 to 100C with elimina-~$ ;
tion of hydrogen halide. Ter-tiary amines or quaternary ammon-ium salts are preferably used as the basic catalysts~ The proportion of the basic catalyst can be from 0.1 to 100 mol%, `~-~3 relative to the acid halides. This process can also be carried `~
out wi-thout a solvent or in the presence of a solvent.
~3 When working up the polyester melts or even before the polycondensation reaction, it is possible to add to -the reaction ~-mass inert additives of all kinds, such as, for example, fillers, reinforcing.materials, especially glass fibres and/or glass . ~, .
spheres, inorganic or organic pigments, optical brighteners, delustering agents, agents for promoting crystallisation and additives for rendering the material incombustible or flame~
~i retarding, such as, for example, antimony trioxide and organic ~ ;
compounds having a high content of chlorine and bromine.
If the polycondensation reaction is carried out dis-continuously, these known measures can be taken even during the last step of the condensation, for example in the solid pha~se condensation or even at the end of the melt condensation. ;
The polyesters according to the inven-tion can be partly crystalline or amorphous, depe-nding on which diols and which - 14 _ ;', , "'~, ''~
r .~

dicarboxylic acids are used as -the star-ting components and the -ratios in which the la-tter are employed.
' The new polyesters are colourless to pale yellow and reprèsent thermoplastic materials from which, after the cus~
tomary moulding processes, such as casting, injec-tion moulding and extrusion, mouldings with valuable thermo-mechanical pro-perties can be produced. -~
The new polyesters are par-ticularly suitable as ~-~
"Engineering Plastic" materials which are suitable for -the pro-duction of shaped ar-ticles, such as cog wheels, containers for ~ chemicals or food, machine parts and equipment parts, sheets, ;~ pIates, films, hot-mel-t adhesives and coatings, and also for the production of semi-fabricated produc-ts which can be shaped by machining.
e polyesters prepared in the examples which follow are `;
more fully characterised by means o~ the following character-is-tic da-ta: The polyesters are characterised by means of those ;
~i morpholog1cal changes which are measured by means of differen- ~ 3 3 tial therm~ analysis on a sample heat-treated for ~ minutes at ~;~ 30C above the melting point or softening point and then rapidly ~; cooled. The quen~led sample is heated at a heating-up speed of 16C/minute by means of the "DSC-lB" differential scanning calorimeter of Messrs. Perkin-Elmer. The thermogram of the sample (compare the diagrammatic representation in Figure 1) , ~ ,:
shows the glass transition temperature (Tg~, -the crystallisation temperature (Tc) and -the melting point (Tm). The glass trans-i-tion tempera-ture is indicated in the thermogram as the point of inflexion at the sudden increase in the specific heat, the ,, ' ',~ ' .
~ - 15 -;... ,., . : . . . . -lV~1~i"39L
crystallisation temperature is indicated as the crest o the exothermic peak and the melting point is indicated as the crest of the endothermic peak. The relative viscosity of the polycondensates of the examples is determined at 30C on solutions of 1 g of polyester in 100 ml of a mixture consisting of -equal parts of phenol and tetrachloroethane. The softening point ~Ts) is de-termined on a Kofler microscope with a heated stage having a heating-up speed of 15C/minute, a cross being formed out of 2 filaments and the softening point being designated as that temperature at which the sharp corners of the cross disappear. The nitrogen content is determined by means of elementary analysis.
Example 1 :`i Preparation of a copolyester from 1,4-butanediol~ dimethyl -terephthalate and a diol A of the formula ... . .

,1~c ~ c~ ~c ~c ~ \c~ c~ ~c . ~cf ~¦2 2 ~ ~ H2 CH2-N~ ~ - CH2 - \ N-CH2-CH2-N N-CH -CH -OH

.,A mixture of 97.1 g of dimethyl terephthalate ~DMT) (0.5 mol), .
~,99.1 g of 1,4-butanediol (1.1 mol)~ 33.2 g of diol A (10 mol% relative to -DMT) and 0.05 g of tetraisopropyl orthotitanate is condensed under an atmos-phere of nitrogen and with slow stirring accordi.ng to the following tempera-ture/pressure programme:
~1 hour at 150 - 200C/N2/atmospheric pressure ; ;~

: ~3 ~:
'j `'. ::
,1 `, . ~
., : . .

::1 . .
, ~ , ' .~ ' .

., ' :

: ` :

~V~ 4 ;: ~
,, 1 hour a-t 200 - 2Gooc/N2/atmospheric pressure , 1 hour a-t 260C/N2/20 mm Hg --~ 0~1 mm Hg '`5 1 hour at 260C/N2/0.1 mm Hg.
i The reac-tion produc-t is then poured out onto a metal ~ . ,; ~ .
,~ sheet to cool under a N2 a-tmosphere.
, The partly crystalline copolyester thus obtained, which , has a horn-like appearance, has the following characteristics:
,i Softening point (Kofler): 190C ;
Relative viscosity: 1.60 `
Glass transi-tion temperat,ure (DSC) 77C - '~
Nitrogen content: 4.00% ~-theory 3~96%) '~
~' Example 2 1 Preparation of a copolyes-ter from 1,4 butanediol ,'i dimethyl terephthalate and a diol B of -the formula - CH CH 0 0 CH CH C~i C~ 0 0 CH CH ' ;~
3 ~ \C/ 3' ' ''~
I I I I I I I I ' ~
HO-~12-CH2-~ N-CH2~N N~C~12-~ N-CH2~N ~-CH2-C~12-~ ,'.
- G C C C~
~ a a ~ a ~' .
,~ ' A mixture of 75 g of dimethyl terephthalate (DMT?
(0.386 mol), 70 g of 1,4-butanediol (0.777 mol), 24.6 g of diol B (10 mol% relative to DMT) and 0.045 g of tetraisopropyl ~i- or-thotitanate is condensed under a nitrogen atmosphere and with ,,`
" i - ~ ~
~ slow stirring according to the following temperature/pressure ',,~ programme; , ,i 1 hour at 160C/N2/atmospheric pressure '~- 2 hours at 160C -~ 245C/N2/atmospheric pressure ~ ~' 1 , - 17 ~
J~
~ , .

. ' '~:
' ;
: . ', .

J ., ~.,: ' ' , ,, ,'. ' . ` ' : ~

`
~. ~

1 hour at 245C/N2/atmospheric pressure -~ 18 mm Hg 30 minutes at 245C/~2/18 mm Hg ~ O.5 mm Hg and 1 hour at 265C/N2/0.5 mm Hg.
~ The reaction product is -then poured out onto a metal `:~ sheet to cool under a N2 atmosphere.
~ me virtually colourless, partly crys-talline copoly-`, ester thus obtained has the following characteristics:
. .
Softening point by Koflers me-thod: 207C - ~
: .
Relative viscosity 1.62 ;~
Glass transition temperature (DSC) 93C
Nitrogen content found: - 3.85% (theory 4.08%) -` -~ Comparison E~
;~ An analogous mixture9 but containing instead of 10 . mol% of the diol according -to Examp:Le 2, 20 moL% of 1,1'~
methylene-bis-[3-(2'-hydroxy-ethyl)--5~5-dimethylhydantoin]
~ ïs condensed under -the conditions quoted in Example 2. A ~ ;
;~ copolyester is obtained in -this way which contains, by way of ;
comparison with -the copolyester according to Example 2, almost `
the same proportion by weight of dimethylhydantoin radicals and which has the properties given in the -table which follows. ; -~
~h,, The following table also gives the figures for a :
i commercially available polybutylene terephthalate~

. :

~ .

. ~ - .

';.

. ,i, .. , , ... , .. " , ., ., , , . : ... . . . .

~ 6~ ~

_ _ _ CopoIyester Copolyester Poly~u-tylene according to according -to -tereph-thalate ~ Example 2 -the comparison .::~J Example .. ~ _ _ . . _ _ y Sotening , point (by 207 Approx. 185 223 Koflers method) C
' ~? _ ~ ~_ Relative -viscosi-ty 1.62 1.70 2.2 ,~ . . . _ ___ "' :;~
Par-tly Partly Partly `~ -crystalline crystalline crystalline .~ _ . __ _ _ _ ~, Glass trans- -~
ition tem~era- 93 59 24 -ture (DSC~ C ~_ ~ I _ _ L _ _ Jii If, instead of 20 mol% of the diol used in the com-parison Example, only 10 mol% are used, a copolyester having a glass transition tempera-ture of only 45C is obtained.
~; Examples_3 The starting products in the molar ratio specified in ~i ~ Table 1 are introduced into a 200 ml glass reactor having a s-tirrer, a nitrogen inlet and a condenser, and 0.01% of titan~
. j , .. ~ .
;~, ium -tetraisopropylate are added as catalyst. The reaction mixture is heated to 250C over -the course of one hour under nitrogen and in an oil bath and is kept a-t -this temperature ~, for a further hour. In the course -thereof 98% of the theore-tical quantity of methanol or phenol distil off.
;!
~j The temperature o~ the oil bath is now adjus-ted to s~f 270C and, after half an hour, a vacuum of 0.2 mm Hg is care~
, fully applied. After this vacuum has been attained, poly-', - 19 ~
. ~,, ,", ,,, , , ' '' ' ~ : ` , ~ , . . , -:'' ~,. ' , :

~ condensation is carried out for -two hours with stirring and ;~. nitrogen is then admitted and the polyester is taken out of the reactor. ~ .
~`
, ..
:~, ~........................... . . . .

; .
, , j . .
'' ~ ' ~ ' `

~ :.
.~ .~, ~ ' ' .`"' ' `;"'" ' '''', : ". '' ~'`, . .: .

~ '-,i.~,' ~` ` ';, ,`'`~ ` ' ' - ~
`''Z ;, ~ ~

; i ,,, ~ , ~
", ~,'Z , , ` . :. ': ', : :' ..':
.. ,, . ,~,. ' :' : `
.'~ `;.` ~' ~ - 20 - ~
.~' . ;,.
,'', , `
,~' ' ":
,, .
,,;;,,,,,"""" " "~,, ,, ", ", ,,, ,, . ., ~

:~
~ v ~ ~
~ o o o ~ o o u~ ~ o o ~ ~ ~
--~ u~ o 0 ~ ~ ~ u~ ~:
: ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
l ~u~
:~ ::
v ~:~
~`~` o ~ ~ ~ ~ ~ ~ ~ o ~ ~ ~
'.. , E~ ~ 0~ O ~ ~ O ~
~l ~
:~
---- - - . '~
~ o oo ~ ~ ~ ~ ~o ~ o~ ~ .c,i ~
a) ~ ~ ~ ~ ~o ~ ~ ~ ~ C--. ~ ....... . :~
: :
~ :`
:` :::
:
~l :~ ~ ~ ~
~ h ~ - c~.l ; 1 h l~ l~ o c`.l 0~ 0 L~ . ::~
: :' t~ ~ I
1 r l ~1 0 r~ 1 - : ~ .
',,-~ ~ 'u~ o ~ , .~ O~O~OOOOOC\l ,.`~ .. .. .. . ... .. .. .. .. .. 1~ :
. ~I r I r I O ~ I r I r I
,.~ ~ . . . 0 ' ' `i ~ .
,,~ ~ 1~ ' Pl ;. ~'.' .
O ~ ~

. ~ ~ m^ m ai n v v^ m^ m ~ ~ ~
h ~1 ~I rl ~` ~1 ~1 ~1 ~1 r I
.~ 0 O O O H O O O O 0 .j U~ ~ 1~ 1 , 1 ~
~ ~ . ~, :
~1 I ~1 . ..
,. 1 ~( o ~ O r-l ~, ,, X ~; ~ V '~ X

;1, ,' , ' :
."

. . .

DMT : Dimethyl terephthalate DPT : Diphenyl tereph-thalate :~
-' DMI : Dimethyl isophthalate ' B 14 : Butanediol-1,4 EG : E-thylene glycol CHDM : Cyclohexanedimethanol-1,4 `.
Diol C~

O~H CH ~ :
CH3 CH O ~ 3 3 ~O-CH2-CH2-~1 N-CH2-CH2-~T N-CH2-CH2-N N-CH2-CH2-OH
~ 11 O "~
;.~ ' ,~

i~ Di.ol D:
~ .

OCH2 CH2-N \ /N 2 ,"i, ~ , :.j , ~,:

:'1 .`; ~

~,'.

" : ~ ~

: ;~, , , . , . . . , , . . . ~ . :
,.. ::: .. - , . . .. . . . .

Claims (6)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. Process for the manufacture of linear, thermoplastic polyesters of the formula I
(I) wherein the carbonyl groups can be linked to the aromatic rings in the meta-or para-position or can be linked to different aromatic rings in the meta-and para-position, E represents an aliphatic radical with 2 to 10 carbon atoms which is linear or is branched by means of the methyl or ethyl group, or the 1,4-dimethylenecyclohexane radical, R1 in each case denotes a hydro-gen atom, or a methyl, ethyl or phenyl group, and R2 denotes a hydrogen atom or, conjointly with R1, denotes the tetramethylene radical, A denotes a radi-cal of the formulae -CH2-, -CH2-CH2-, , , or U1 denotes a radical of the following formulae , , or .

wherein B1 and B2 independently of one another each denote a hydrogen atom or an alkyl radical with 1 to 4 carbon atoms, and U2 has the same meaning as U1 or denotes a radical of the formula wherein D1 and D2 independently of one another each denote a hydrogen atom, an alkyl radical with 1 to 4 carbon atoms or the phenyl group or, conjointly, denote the pentamethylene radical, characterised in that n mols, or if appropriate n + m mols, of terephthalic acid and/or isophthalic acid or polyester-forming derivatives thereof are polycondensed with n mols of a diol of the formula II
(II) wherein R1, R2, A, U1 and U2 have the same meaning as in formula I, if appropriate mixed with m mols of a diol of the formula III
HO-E-OH (III) wherein E has the same meaning as in formula I, corresponding to the mol fraction = 0.02 to 1.0, and in the presence of a catalyst, in a known manner to give a relative viscosity of 0.5 to 4Ø

2. Process according to Claim 1, characterised in that terephthalic acid and/or isophthalic acid or polyester-forming derivatives thereof are polycondensed corresponding to the mol fraction = 0.05 to 1.0 to give a relative viscosity of 1.0 to 3Ø

3. Process according to Claim 1, characterised in that, in formula II, R1 and R2 each denote a hydrogen atom, A represents a methylene radical or ethylene radical, U1 denotes a radical of the formulae , or and U2 denotes a radical of the formula wherein D1 and D2 represent the methyl group or, conjointly, represent the pentamethylene radical, that, in the formula III, E repeesents an alkylene radical with 2 to 4 carbon atoms, and that polycondensation is carried out corresponding to the mol fraction = 0.05 to 1.0 to give a relative viscosity of 1.0 to 3Ø

4. Process according to Claim 1, characterised in that compounds of the formula , are used as the diols of the formula II.

5. Process according to Claim 4, characterised in that polycon-densation is carried out corresponding to the mol fraction = 0.2 to l.

6. Linear thermoplastic polyesters having a relative viscosity of 0.5 to 4.0, measured at 30°C on a 1% strength solution consisting of equal parts of phenol and tetrachloroethane, which are characterised by the general formula I

(I) wherein the carbonyl groups can be linked to the aromatic rings in the meta-or para-position or can be linked to different aromatic rings in the meta-and para-position, E represents an alipahtic radical with 2 to 10 carbon atoms which is linear or is branched by means of the methyl or ethyl group, or represents the 1,4-dimethylenecyclohexane radical, R1 denotes in each case a hydrogen atom or the methyl, ethyl or phenyl group, and R2 denotes a hydro-gen atom or, conjointly with R1, denotes the tetramethylene radical, A de-notes a radical of the formulae -CH2-, -CH2-CH2-, , or U1 denotes a radical of the formulae , , or wherein B1 and B2 independently of one another each denote a hydrogen atom or an alkyl radical with 1 to 4 carbon atoms, and U2 has the same meaning as U1 or denotes a radical of the formula wherein D1 and D2 independently of one another each denote a hydrogen atom, an alkyl radical with 1 to 4 carbon atoms or the phenyl radical or, conjointly denote the pentamethylene radical, m represents 0 or integers and n represents integers, it being possible for the mol fraction derived from n and m to assume values from 0.02 to 1.