CA1088501A - Process for the polymerisation of chloroprene - Google Patents
Process for the polymerisation of chloropreneInfo
- Publication number
- CA1088501A CA1088501A CA280,710A CA280710A CA1088501A CA 1088501 A CA1088501 A CA 1088501A CA 280710 A CA280710 A CA 280710A CA 1088501 A CA1088501 A CA 1088501A
- Authority
- CA
- Canada
- Prior art keywords
- acid
- polymerisation
- weight
- chloroprene
- activator
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F36/00—Homopolymers and copolymers of compounds having one or more unsaturated aliphatic radicals, at least one having two or more carbon-to-carbon double bonds
- C08F36/02—Homopolymers and copolymers of compounds having one or more unsaturated aliphatic radicals, at least one having two or more carbon-to-carbon double bonds the radical having only two carbon-to-carbon double bonds
- C08F36/04—Homopolymers and copolymers of compounds having one or more unsaturated aliphatic radicals, at least one having two or more carbon-to-carbon double bonds the radical having only two carbon-to-carbon double bonds conjugated
- C08F36/14—Homopolymers and copolymers of compounds having one or more unsaturated aliphatic radicals, at least one having two or more carbon-to-carbon double bonds the radical having only two carbon-to-carbon double bonds conjugated containing elements other than carbon and hydrogen
- C08F36/16—Homopolymers and copolymers of compounds having one or more unsaturated aliphatic radicals, at least one having two or more carbon-to-carbon double bonds the radical having only two carbon-to-carbon double bonds conjugated containing elements other than carbon and hydrogen containing halogen
- C08F36/18—Homopolymers and copolymers of compounds having one or more unsaturated aliphatic radicals, at least one having two or more carbon-to-carbon double bonds the radical having only two carbon-to-carbon double bonds conjugated containing elements other than carbon and hydrogen containing halogen containing chlorine
Abstract
ABSTRACT OF THE DISCLOSURE
A process is provided for the polymerization of chloroprene (optionally in the presence of comonomers copolymerisable with chloroprene) in aqueous emmision in the presence of known-surface active compounds in the alkaline, neutral or acid pH-range, wherein as an activator system there is used a three-component combination of an inorganic peroxy compound, anthraquinone-2-sulphonic acid-alkali salt and formamidine sulphinic acid.
A process is provided for the polymerization of chloroprene (optionally in the presence of comonomers copolymerisable with chloroprene) in aqueous emmision in the presence of known-surface active compounds in the alkaline, neutral or acid pH-range, wherein as an activator system there is used a three-component combination of an inorganic peroxy compound, anthraquinone-2-sulphonic acid-alkali salt and formamidine sulphinic acid.
Description
i(.l~SOl ~`
This inNention relates to a prooess for the polymerisation of chloroprene, opticoally in the presenoe of cx mDIamers~ in aqueous emLlsion in the presence of known surfa e active compounds in the alkaline, neutral or acid pH-range, a ~,~ination of an in~rganic peroxy compound, anthraquinone-2-sulphonic acid~aIkali salt and fcrn~u1Jilne sulphinic acid being used as an activator system.
m e polymerisation of chlorcprene has bong been kncwn `-and has frequently been described in the li~rature~
cf. for example Encyclopedia of PDlymer Science and -Technology, Vbl. 3, pages 705-730, Unibed States Pabent Nos.
This inNention relates to a prooess for the polymerisation of chloroprene, opticoally in the presenoe of cx mDIamers~ in aqueous emLlsion in the presence of known surfa e active compounds in the alkaline, neutral or acid pH-range, a ~,~ination of an in~rganic peroxy compound, anthraquinone-2-sulphonic acid~aIkali salt and fcrn~u1Jilne sulphinic acid being used as an activator system.
m e polymerisation of chlorcprene has bong been kncwn `-and has frequently been described in the li~rature~
cf. for example Encyclopedia of PDlymer Science and -Technology, Vbl. 3, pages 705-730, Unibed States Pabent Nos.
2,394,291 and 2,567,117; British Patents Nos. 512,458, 1,048,235 and 1,094,321; and Gbrman Offenlegungsschrifts Nos. 2,008,674, 3,047,450 and 2,241,394.
m e latex obtained in the polymerisation stage can be warked up into rubber ~y low-temperature or by ~ -electrolyte ocagulation. These prooesses are described for exa~ple, in Chem. Engng. PnDgr, 43, 391 (1947), and in German Patent Nos. 1,051,506 and 1,111,804.
The latices may also be directly prooessed as described for example, in the jou~nal "Gummi, Askest, Khnstsboffe~
1973, ~os. 5-7, pp. 394-398, 494-503 and 574-582 and in the book entitled '~ prene Labex" ~y John C. ~rl, of E.J. Du Pont de Ne~urs & Co. tInc.), W~lnu`l~rb~n, C - 1 _ 10885~11 Delaware (Uhited States of America).
The polymerisation temperature laryely determines the servi oe properties of the polymer:
A product produoed at relatively low temperature has a marked tendency towards crystallisation and is eminently suitable for the production of adhesives.
Polymer p ~ d at elevated temperature can be used for the production of rubber pLoducts with valuable pls~:rtics (for example conveyor belts, nune and ~P~p-sea cables, bridge be~rings etc.).
In the polymerisation of chloroprene, the starting monomers used æ e normally stabilised against spontaneaus polymerisation because chlor~prene shcws a n~rked affinity for polymerisation (cf. Houben~Wbyl, Methoden der organischen Chcmie, ~1. XIV/l. MakromDlekulare Stoffe, part 1, Georg Thieme Verlag Stuttgart, 1961, pages 733 et ~1) and becàuse the exDthermic reaction runs out of conLLul ~ery easily, particularly in the case of large batches. m e stabilizers used include, for exa~ple, pher~rllul~ane, E~tert.-butyl pyrocatechol and nitrogen manoxide.
Gbrman Auslegeschrift No. 1,097,689 descr;h~c an advantageous polymerisation procæss for chloroprene stabilised with phenothiazine for example against uncontrolled and premature polymerisation. m ere is no need for the stabiliser "
to be æ parated off before polymerisation, which eldninabes the need for, and danger in~ol~ed in, storing the unstabilised chlorcprene in supercooled form in the strict a~sence of 1088SOl oxygen In addition, poly ors with ra~ourable proportlo~
are obtained by poly ori~atloD ~ron ~ta~illcod ¢hloroprone The advsntage Or carrylng out poly~erisation in tho pro~nco ot stabillsers i~ obtained ~y u~in~ ror - ldln- UlphlDlC
acid ln quantities Or rro 0 1 to 0 4 % by ~ ht, baJod on the a ount Or ~ononer u~ed Stabilised chloroprene oan al80 bo poly eri-od wlth 0 1 % by woight (ba~od on ono-or) Or azo ratty acld di~itrilos, as descrlbed in US Patent No 2,707,180 T~o azo co pound~
release starter radicals artor t~orral doconposltlon 80 that, under the de~cribed roaotion conditlons, olo~atod te~peratur~s arc required tor obtainin~ an adequato roactlon velocity Hardly any poly er 1~ obtalDed wltb porQ~y disulphates in~tesd ot the azo ~atty a¢id dlnitrllos When the poly~sri~atlon or chloroprene is aoti~atod with peroxy disulphates, irregular polynerlsatlon volocltlo~
are observed ~ccording to US Patent No 2,426,854, those dlrticulties can be ell~inated by ~ddin4 8 all qu~ntltles Or snthraqulnone-2-sulphonlc aoid (in the ior or lts alkali salt), ~he decomposltlon o~ tho lnorgsnic pero~y co~pound~
(rer e~a~ple the peroxy dlsulphate~) is groatly doponde~t upon te~perature unde~ constant reaction condltlo~e In order to obtaln an ade~u-to ro~otlon ~elooley even at rel~ e~y low to poratures, US Patent No 2,~17,03~ propo~es the ~ddlt~o~
Or reducing co-pounds, ~or eYample potas~lue ferri~yanlde ln the strlct absenoo o~ osy~en Tho polyrer~satlo~
~e A 17 575 _ 3 _ 10~8501 reaction may even be carried out at relatively low temperatures with a~ines as the decompDsition catalyst (Cf.Dispersionensynthetischer Hochpolymerer (Dispersions of Synthetic High polymers~, Part I, by Frio~rich ~olscher, Springer Verlag PPrlin-HeideIberg, New York, 1963.).
It is well kncwn amon~ experts that, where a reacticn is initiated with peroxy disulpbate, the amount of activator has to be kept as small as possible and the radical-fdrming pro oe ss has to take place as uniformly as possible in order to obtain products of high quality. m e number of poly-merisation initiatiors and hence the number of polymer chains increases with increasing addition of persulphate.
In addition, the radical-forming reaction has to continue throughout the entire polymerisation time.
Etut~Y~more, it is known that a low consumptian of -~
activator oontribubes oonsiderably tcwards reducing or a~iding coagulate formation during tbe polymerisation reaction. By using an activator system oonsist~ng of an in, organic pero~y oompound, anthra4uinone-2-sulphonic acid-alkali salt, preferably sodium salt, and formamidine sulphinic acid, it was surprisingly possible to achieve the required obiective n~mely red w ing the amDunt of activator avoiding dbposits, obtaining a more unifarm polymer structure and, hence, a fa~Durable range of servioe properties.
The inventian, therefore, provides a process for the polymer;c~tian of chlorcprene which msy contain up to 50~ `;
by weight of a comanomer oopolymerisable with chloroFrene in an aqueous emulsion in the presence of kncwn surfaoe-active Ccl po~cd~ in the alkaline, neutral o~ acid pH- ~ -range, whÆrein the thuEY~ ponent ccmbination of an inorganic percxy Oa~pDUnd, anthraS~i oone-2-sulphonic acid 1 0 ~ 8 5 0 1 -alkali salt and fcr~m ~dine sulphinic acid is l~cP~ as an -activator system.
Also, the inVentiQn provides an activator/initiator combination for the poly~erisatiQn of chloroprene ccnsisting of 95 to 50% by weight of formamidine sulphinic acid, 4.5 to 25% by weight of an inorganic peroxy ccnpound and 0.5 to 2.5% by weight of the aIkali ~lt of anthraquinoner2-sulphonic acid. Preferably the quantitative ratio of the pe m xy conpoun~
to the alkali salt is in the range of from 2:1 to 10:1.
Fbr exa~ple, it is possible to considerably ~mprove the visoosity stability of the polychloroprene latex, a property which is of particular advantage in cases *here the latex is used as an adhesive. In the radical emulsion poly~erisation of chloroprene at 1ow temperatures, there is the further advantage that, where the prccess is carried out oontinuously the polymerisation temperature of, for example, lo& can be lowered by a few degrees centrigrade without reducing the polymerisation velocity. As kncwn to the ~xpert, a reductian of a few degrees in the polymeris tian temperature in this range produces a distinct increase in crystallisation. `
The activat~Dr oombination according to the invention may be used with ad~antage ~oth for the batch polymerisation an~
also for the cr~-tinuous polymerisation o~ chloroprene, its advantages being particularly apparent in continuous wDr~ing. m e oombination of an inorganic E#~XXXy ccn~x~md, anthraquin~oe-2-sulphonic acid-alkali salt and formamidine sul p inic acid shows the most marked advantages over oonventional activator systems in the alkaline-pH-range. 5inoe the dbccmpo~ition of inorganic peroxy acGpcuLdh is distinctly dependent upon the pH-value of the emulsiQn with all other parameters kept oonstant, the effect of using the activator combination acoording to the invention is not as p~c~LaYnoel - '.
in the neutral and acid range as in the alkaline range.
The thre#rcxDllment contination of inorganic F~XXKy ccn~x~md prefer~hly alkali salt, aIkali salt of anthr~u~L~Yxnc-2-sulphonic acid and fcQno;~ ne sulpbinic acid is advantageously used in quantities of fron 0.02 to 0.6% by weight and more especially in quantities of fra~ 0.04 to 0.2% by weight, based -:
on the m~ers us~d. me three~nt carbination itself prefera~ly c~sists of fmm 95 to 50% ~y weight of formamidine sulphinic acid, fr01 4.5 to 25% by weight of inor~nic peroxy ca~4Ound and LL~all O.S to 25% of the alkali salt of anthraqui~2-sulphanic acid, the quantitative ratio of peroxy o~nd to the aL~sali salt being with particular preferenoe in the range of fmm 2:1 ~ 10:1.
By C0-activation with f~midine sulphinic acid, it is -possible to control the deoa~ositio~ of the inorganic :
p~roxy c~pour~, the anthraquincn~2-sulEihinic acid present suppressing induction periods of the per~ c~. ~`.
In ~his way, a uniform radical stream is ~btair~ed in the ~ lsion durin~ the pol~merisatian reaction and the ~ ptia~
of activatar is kept low. `"
The polymerisatian reactian is carried aut in ~ncwn ~. ;
~nner as an emulsion polymerisation reaction. `~
Suitable inor~anic peroxy CCn~X~lnd8ane the known oompcqnds such as, for exa~ple, percxy suiphates and di-lOWSOl sulphates, peroxy phosphates, peroxy borabes and hy~bx~n peroxide, peroxy disulphates being preferred by virtue of their availability.
Suitable emulsifiers are the kncwn anianic, cationic, non-ionic and ~ oberic surface-active crllxa~nis.
m e following are mentioned as examples of suitable emulsifiers:
(a) anionic emLlsifiers:
aIkali metal salts of disproportionabed abietic acid of which the productian is described in Uhited States Pabents ~os. 2,201,237 and 2,154,629; alkali ~etal salts of saturabed anq~or unsaturabed C6-C25-fatty acids;
aIkali metal salts of aIkylated or nan-alkylated naphthalene sulphanic acids which have been ccndenoed with -formaldehyde and of which the production is described by R.S. Earrows and G.W. Scott in Tn~. eng. C~n. 40, 2193 (1948); ~`~
aLk~l benzene sulphates, alkyl benzene sulphonabes, aIkenol polyoxethylate sulpbabes, aloohol isoethionabe, sulphosuccinic acild esbers, alkali me~Al salts of the sulphates of aliphatically aIkylabed ph~nDls or naphthDls, ~b) cationic emulsif;Prs;
quaternary ammDnium halides and quabernary carboxy-- methylated ammonium halides.
(c) non-ionic e~Llsifiers:
ethylene or propylene adducts of fatty alcohDls, fatty acids, fatty acid amides, alkylated or non-alkylated p~DlS Y
.
10885~1 (d) amphoteric emulsifiers:
O CH ~+~
R-C-NH-(CH2)3 N,-C~2-oOO
R = a saturated or unsaturated, linear or branched C8-C18-alkyl r~ical. ;
m e emulsifiers are used, either individually or in oombination, in quantities sufficient to guarantee a surface-active effect. Depending upon the type of conpcund used, the combinations selected for the surface~
active substances and the pH-range, the quantities of emLlsifier used may vary between 2 and 6% by weight, based on the qyantity of monomers used.
m e polymerisation reaction may be carried out at temperatures in the range of fram 0 to 70 & and is preferably -,;~
carried out at temperatures in the range of from 5 to 55 & .
; ..
It is advisable to add the inorganic peroxy compound to the alkali CAlt of anthrdq~ui~ne-2-sulpbonic acid in the agueous phase before the beginning of polymerisation and ;`~
then to start the polymerisation reaction with the fornalidinc ;~
sulphinic acid. ~n this way, the course of the polymerisation -,,: -.; . . , reaction can also be effectively cantrDlled by measured additian.
DepyyylLnq upon the application envisaged for the polym~r, the nDnomer i9 ccsN~:rbel tD a leNel of frcn 50 to 99%, conversions of from 65 to 70% being suitable for rubbers for obtain~ng advantageous servi oe prcpertie8, whilst latice8 of the t~pe required for strengthening paper or fDr refining - -;
bitumen are produced with a high conversion (up bD 99~3.
iO~SOl For cal~rying out tbe procoss, chloropreno ay bo polymerlsed on it8 o~n or ay bo replaoed by up to 50 ~
by weight o~ another co~pound copolynerisable ~ith chloropr~o, tor example acrylonitrile, ~ot~orylonltrile, o-ohloro-acrylonitrile, ao~lic acld estors, ~ethaorylio acld e~t-ro, vinylidene chloride, styrene, ~inyl toluenes, 1,3-~utadi-no, l-chloro-l,3-butadiene, 2,;-dlchloro-1,3-butadlene or 2-o~loro-
m e latex obtained in the polymerisation stage can be warked up into rubber ~y low-temperature or by ~ -electrolyte ocagulation. These prooesses are described for exa~ple, in Chem. Engng. PnDgr, 43, 391 (1947), and in German Patent Nos. 1,051,506 and 1,111,804.
The latices may also be directly prooessed as described for example, in the jou~nal "Gummi, Askest, Khnstsboffe~
1973, ~os. 5-7, pp. 394-398, 494-503 and 574-582 and in the book entitled '~ prene Labex" ~y John C. ~rl, of E.J. Du Pont de Ne~urs & Co. tInc.), W~lnu`l~rb~n, C - 1 _ 10885~11 Delaware (Uhited States of America).
The polymerisation temperature laryely determines the servi oe properties of the polymer:
A product produoed at relatively low temperature has a marked tendency towards crystallisation and is eminently suitable for the production of adhesives.
Polymer p ~ d at elevated temperature can be used for the production of rubber pLoducts with valuable pls~:rtics (for example conveyor belts, nune and ~P~p-sea cables, bridge be~rings etc.).
In the polymerisation of chloroprene, the starting monomers used æ e normally stabilised against spontaneaus polymerisation because chlor~prene shcws a n~rked affinity for polymerisation (cf. Houben~Wbyl, Methoden der organischen Chcmie, ~1. XIV/l. MakromDlekulare Stoffe, part 1, Georg Thieme Verlag Stuttgart, 1961, pages 733 et ~1) and becàuse the exDthermic reaction runs out of conLLul ~ery easily, particularly in the case of large batches. m e stabilizers used include, for exa~ple, pher~rllul~ane, E~tert.-butyl pyrocatechol and nitrogen manoxide.
Gbrman Auslegeschrift No. 1,097,689 descr;h~c an advantageous polymerisation procæss for chloroprene stabilised with phenothiazine for example against uncontrolled and premature polymerisation. m ere is no need for the stabiliser "
to be æ parated off before polymerisation, which eldninabes the need for, and danger in~ol~ed in, storing the unstabilised chlorcprene in supercooled form in the strict a~sence of 1088SOl oxygen In addition, poly ors with ra~ourable proportlo~
are obtained by poly ori~atloD ~ron ~ta~illcod ¢hloroprone The advsntage Or carrylng out poly~erisation in tho pro~nco ot stabillsers i~ obtained ~y u~in~ ror - ldln- UlphlDlC
acid ln quantities Or rro 0 1 to 0 4 % by ~ ht, baJod on the a ount Or ~ononer u~ed Stabilised chloroprene oan al80 bo poly eri-od wlth 0 1 % by woight (ba~od on ono-or) Or azo ratty acld di~itrilos, as descrlbed in US Patent No 2,707,180 T~o azo co pound~
release starter radicals artor t~orral doconposltlon 80 that, under the de~cribed roaotion conditlons, olo~atod te~peratur~s arc required tor obtainin~ an adequato roactlon velocity Hardly any poly er 1~ obtalDed wltb porQ~y disulphates in~tesd ot the azo ~atty a¢id dlnitrllos When the poly~sri~atlon or chloroprene is aoti~atod with peroxy disulphates, irregular polynerlsatlon volocltlo~
are observed ~ccording to US Patent No 2,426,854, those dlrticulties can be ell~inated by ~ddin4 8 all qu~ntltles Or snthraqulnone-2-sulphonlc aoid (in the ior or lts alkali salt), ~he decomposltlon o~ tho lnorgsnic pero~y co~pound~
(rer e~a~ple the peroxy dlsulphate~) is groatly doponde~t upon te~perature unde~ constant reaction condltlo~e In order to obtaln an ade~u-to ro~otlon ~elooley even at rel~ e~y low to poratures, US Patent No 2,~17,03~ propo~es the ~ddlt~o~
Or reducing co-pounds, ~or eYample potas~lue ferri~yanlde ln the strlct absenoo o~ osy~en Tho polyrer~satlo~
~e A 17 575 _ 3 _ 10~8501 reaction may even be carried out at relatively low temperatures with a~ines as the decompDsition catalyst (Cf.Dispersionensynthetischer Hochpolymerer (Dispersions of Synthetic High polymers~, Part I, by Frio~rich ~olscher, Springer Verlag PPrlin-HeideIberg, New York, 1963.).
It is well kncwn amon~ experts that, where a reacticn is initiated with peroxy disulpbate, the amount of activator has to be kept as small as possible and the radical-fdrming pro oe ss has to take place as uniformly as possible in order to obtain products of high quality. m e number of poly-merisation initiatiors and hence the number of polymer chains increases with increasing addition of persulphate.
In addition, the radical-forming reaction has to continue throughout the entire polymerisation time.
Etut~Y~more, it is known that a low consumptian of -~
activator oontribubes oonsiderably tcwards reducing or a~iding coagulate formation during tbe polymerisation reaction. By using an activator system oonsist~ng of an in, organic pero~y oompound, anthra4uinone-2-sulphonic acid-alkali salt, preferably sodium salt, and formamidine sulphinic acid, it was surprisingly possible to achieve the required obiective n~mely red w ing the amDunt of activator avoiding dbposits, obtaining a more unifarm polymer structure and, hence, a fa~Durable range of servioe properties.
The inventian, therefore, provides a process for the polymer;c~tian of chlorcprene which msy contain up to 50~ `;
by weight of a comanomer oopolymerisable with chloroFrene in an aqueous emulsion in the presence of kncwn surfaoe-active Ccl po~cd~ in the alkaline, neutral o~ acid pH- ~ -range, whÆrein the thuEY~ ponent ccmbination of an inorganic percxy Oa~pDUnd, anthraS~i oone-2-sulphonic acid 1 0 ~ 8 5 0 1 -alkali salt and fcr~m ~dine sulphinic acid is l~cP~ as an -activator system.
Also, the inVentiQn provides an activator/initiator combination for the poly~erisatiQn of chloroprene ccnsisting of 95 to 50% by weight of formamidine sulphinic acid, 4.5 to 25% by weight of an inorganic peroxy ccnpound and 0.5 to 2.5% by weight of the aIkali ~lt of anthraquinoner2-sulphonic acid. Preferably the quantitative ratio of the pe m xy conpoun~
to the alkali salt is in the range of from 2:1 to 10:1.
Fbr exa~ple, it is possible to considerably ~mprove the visoosity stability of the polychloroprene latex, a property which is of particular advantage in cases *here the latex is used as an adhesive. In the radical emulsion poly~erisation of chloroprene at 1ow temperatures, there is the further advantage that, where the prccess is carried out oontinuously the polymerisation temperature of, for example, lo& can be lowered by a few degrees centrigrade without reducing the polymerisation velocity. As kncwn to the ~xpert, a reductian of a few degrees in the polymeris tian temperature in this range produces a distinct increase in crystallisation. `
The activat~Dr oombination according to the invention may be used with ad~antage ~oth for the batch polymerisation an~
also for the cr~-tinuous polymerisation o~ chloroprene, its advantages being particularly apparent in continuous wDr~ing. m e oombination of an inorganic E#~XXXy ccn~x~md, anthraquin~oe-2-sulphonic acid-alkali salt and formamidine sul p inic acid shows the most marked advantages over oonventional activator systems in the alkaline-pH-range. 5inoe the dbccmpo~ition of inorganic peroxy acGpcuLdh is distinctly dependent upon the pH-value of the emulsiQn with all other parameters kept oonstant, the effect of using the activator combination acoording to the invention is not as p~c~LaYnoel - '.
in the neutral and acid range as in the alkaline range.
The thre#rcxDllment contination of inorganic F~XXKy ccn~x~md prefer~hly alkali salt, aIkali salt of anthr~u~L~Yxnc-2-sulphonic acid and fcQno;~ ne sulpbinic acid is advantageously used in quantities of fron 0.02 to 0.6% by weight and more especially in quantities of fra~ 0.04 to 0.2% by weight, based -:
on the m~ers us~d. me three~nt carbination itself prefera~ly c~sists of fmm 95 to 50% ~y weight of formamidine sulphinic acid, fr01 4.5 to 25% by weight of inor~nic peroxy ca~4Ound and LL~all O.S to 25% of the alkali salt of anthraqui~2-sulphanic acid, the quantitative ratio of peroxy o~nd to the aL~sali salt being with particular preferenoe in the range of fmm 2:1 ~ 10:1.
By C0-activation with f~midine sulphinic acid, it is -possible to control the deoa~ositio~ of the inorganic :
p~roxy c~pour~, the anthraquincn~2-sulEihinic acid present suppressing induction periods of the per~ c~. ~`.
In ~his way, a uniform radical stream is ~btair~ed in the ~ lsion durin~ the pol~merisatian reaction and the ~ ptia~
of activatar is kept low. `"
The polymerisatian reactian is carried aut in ~ncwn ~. ;
~nner as an emulsion polymerisation reaction. `~
Suitable inor~anic peroxy CCn~X~lnd8ane the known oompcqnds such as, for exa~ple, percxy suiphates and di-lOWSOl sulphates, peroxy phosphates, peroxy borabes and hy~bx~n peroxide, peroxy disulphates being preferred by virtue of their availability.
Suitable emulsifiers are the kncwn anianic, cationic, non-ionic and ~ oberic surface-active crllxa~nis.
m e following are mentioned as examples of suitable emulsifiers:
(a) anionic emLlsifiers:
aIkali metal salts of disproportionabed abietic acid of which the productian is described in Uhited States Pabents ~os. 2,201,237 and 2,154,629; alkali ~etal salts of saturabed anq~or unsaturabed C6-C25-fatty acids;
aIkali metal salts of aIkylated or nan-alkylated naphthalene sulphanic acids which have been ccndenoed with -formaldehyde and of which the production is described by R.S. Earrows and G.W. Scott in Tn~. eng. C~n. 40, 2193 (1948); ~`~
aLk~l benzene sulphates, alkyl benzene sulphonabes, aIkenol polyoxethylate sulpbabes, aloohol isoethionabe, sulphosuccinic acild esbers, alkali me~Al salts of the sulphates of aliphatically aIkylabed ph~nDls or naphthDls, ~b) cationic emulsif;Prs;
quaternary ammDnium halides and quabernary carboxy-- methylated ammonium halides.
(c) non-ionic e~Llsifiers:
ethylene or propylene adducts of fatty alcohDls, fatty acids, fatty acid amides, alkylated or non-alkylated p~DlS Y
.
10885~1 (d) amphoteric emulsifiers:
O CH ~+~
R-C-NH-(CH2)3 N,-C~2-oOO
R = a saturated or unsaturated, linear or branched C8-C18-alkyl r~ical. ;
m e emulsifiers are used, either individually or in oombination, in quantities sufficient to guarantee a surface-active effect. Depending upon the type of conpcund used, the combinations selected for the surface~
active substances and the pH-range, the quantities of emLlsifier used may vary between 2 and 6% by weight, based on the qyantity of monomers used.
m e polymerisation reaction may be carried out at temperatures in the range of fram 0 to 70 & and is preferably -,;~
carried out at temperatures in the range of from 5 to 55 & .
; ..
It is advisable to add the inorganic peroxy compound to the alkali CAlt of anthrdq~ui~ne-2-sulpbonic acid in the agueous phase before the beginning of polymerisation and ;`~
then to start the polymerisation reaction with the fornalidinc ;~
sulphinic acid. ~n this way, the course of the polymerisation -,,: -.; . . , reaction can also be effectively cantrDlled by measured additian.
DepyyylLnq upon the application envisaged for the polym~r, the nDnomer i9 ccsN~:rbel tD a leNel of frcn 50 to 99%, conversions of from 65 to 70% being suitable for rubbers for obtain~ng advantageous servi oe prcpertie8, whilst latice8 of the t~pe required for strengthening paper or fDr refining - -;
bitumen are produced with a high conversion (up bD 99~3.
iO~SOl For cal~rying out tbe procoss, chloropreno ay bo polymerlsed on it8 o~n or ay bo replaoed by up to 50 ~
by weight o~ another co~pound copolynerisable ~ith chloropr~o, tor example acrylonitrile, ~ot~orylonltrile, o-ohloro-acrylonitrile, ao~lic acld estors, ~ethaorylio acld e~t-ro, vinylidene chloride, styrene, ~inyl toluenes, 1,3-~utadi-no, l-chloro-l,3-butadiene, 2,;-dlchloro-1,3-butadlene or 2-o~loro-
3-methyl-1,3-butadiene, By adding known ~odi~ying oo~pounds, ror e~u ple mercaptans, santhogone dlsulphldes, qulnones, benzyl lodide or iodoton~, it 1~ possl~le to ~ary tho structure and properties ot the polyrers ~ithln ~id~ li~lts.
Unreacted organlc oo~pQunds ~ay ~e re o~ed by ~toa~
distillatlon, tor e~u ple at 50C and under an ab~oluto pressure ot 20 Torr.
The rollo~lng Esa ples are lntonded to illu~trate tho invention wlthout li~iting It ln any way.
EXAMPLE I
Poly~erlsation acoordin~ to the Drior art To produce the poly er, a ni~ture Or tho rollo~lng co~position was poly~erised under nit~ogen:
Chloroprene 100,00 parts by ~elght n-Dodecyl ~ercaptan 0.25 p~rts by ~eight Phe~othiaslne 0,01 part by ~oight Desalted water 120,00 parts by ~eight Sodiu~ salt Or a disproportionated abietic acid 4.00 parts by ~elght Caustic soda 0.6 p~rt by ~elght Sodium salt ot the oondensatlon product Or napthaleno sulphonic acld and ~on aldohyde 0.6 part by ~eig~t Le A 17 575 - 9 -10~8501 The poly~erisation reaction ~a~ carrlod out at 40C
by running B 1% aqueous ~olution o~ Sor~a idino sulphinic acid continuou41y into the ~isturo.
The reaction was stopped at a nono er oon~or~ion oi ~5~ by r~moving the ~ono~er.
The consu~ption of actiYator a~ounted to 0.21 ~ by welght, ba~ed on the quantlty Or ~ono~or usod, Polymerisation according to Drlor art The procedure was as described ln E~a~plo 1, oscept that the rorma~idine sulphinic acid was roplacod by a 2 ~ aquoous ~olution Or potassiu~ pero~y disulphate containlng 10 %
by woight Or the sodiu~ salt oi aDthraquinone-2-sulphonic acid, the quantity by weight being basod on K2S208.
0.17 % by weig~t Or X2S208 hsd been consu~od by tho tino a mono~er conversion Or 65 % was roached.
Poly~erisation with the activator ~sten a¢cordlDg to tho invention The procedure was as described in E~a plo I, escopt thatO.O~
by weight Or K2S208 and 0.05 ~ by welght o~ anthr~quinone-2-sulphonic acid (sodiu~ salt) wore added to the i~ture.
The poly~erisation reaction co~menced i~mediatoly a~tor the beginning Or the dropwise addition Or tho 1 ~ aqueous rorma~idine sulphinic aold salution, 0.04 % by weight ot ~on~ldlne sulphinlo acid had been consumod by tho ti~e tho ~ono~er con~orsion reaohed ~5f-(All quantitios aro basod on the quantity Or nono er uoed).
Le A ~7 ~75 - 10 -10~8SO~
A mixture of the rollowing composition ~a8 polymorised under nitrogen:
Chloroprene lO0.0 parts by welght Phenothiazone o.005 part by weight n-Dodecyl mercaptan O.lO part by weight Desalted water ~0.0 parts by woight Sodlum salt Or a disproportionated abietic aci~ 2.8 parts by weight ~austic soda 0.5 part by weight Adduct of i-nonyl phenol and lO mole~
o~ ethylene amide 0.5 part by weight Polymerisation wa~ carried out at 50C by running a 2.~% a~ueous ~ormamidine ~ulphinic acld cont$nuous}y into the mi~ture.
The monomer was converted to a level o~ 99%. The consumption of acti~ator amounted to 0.32 % by welght, based on monomer.
~0 EXAMPLE 5 The procedure was as de~cribod in Example 4, escept that 0.05 ~ by weight Or K2~208 and 0.0005 ~ by ~eight oi anthraquinone-2-sulphonic a¢id (~odium salt) were added to the mixture before the beglnning Or the polymerisation reaction.
OoOB % by weight oi rormamidine ~ulphlnic aeid ~a8 required to obtain a mono~er oonYersion Or 99% (all quantitie9 are based on monomer).
Le A 17 57~
1~
~MPLE 1~
Polymerisation according to the Drior art To produce the polymer~ a mixture or the iollo~ing composition W8~ poly~erised under nltrogens Chloroprene 98 0 parts by wolght Methacrylic acid (stablli~ed wlth 50 ppm of ~ydroqulnone methyl ether)2 0 parts by ~el~ht Phenothiazine 0 01 part by weight n-Dodecyl mercaptan 0 20 part by ~eight Desalted w~ter 85 0 parts by ~elght Parafiin sulphonate 3 5 parts by woight~
Adduct of 1 mole Or stearyl alcohol and 20 moles o~ ethylene oside1 0 part by ~oight Conden~atlon product oi naphthaleno sulphonic acld and ror~aldehyde0 3 part by ~elght The reaction was oarrled out at a te perature ln tho range Or irom 45 to 50C A~ter the addltlo~ o~ a 2 5 %
aqueous ror~a~idine sulphinlc acld solutlon, the polynorlsatlon reaction began vigorously and nocossitated inte~sl~o cooling The fonmamidine sulphinio aold solution ~as thon addod dropwise at suoh a rate that the polyaeri~atlon teaperature re~ained in the required range -~; 0 1~ ~ by welght of ior~a ldine ~ulphlnic aold, basod ; on monoaer, had boen consumed by the tiao tho ao~oaor ~o~orslon reached 99 ~0 On co~pletion oi tho roaotion, tho a~turo had ~ p~alue ~ Or 4 0 -~ E~AMPLE 7 The repotitlon oi E~a~plo 6 wlth 0 004 ~ by weight of X2S208 ~nd 0 0004 ~ by woight oi ~nthr~Qul~o~e~ ulphi~lc Le A 17 575 - 12 -.
, .. . . . . .
lllW501 æ id (_odiun~ salt) produced a reduction in ~he ccnsulFtion of fornEm~idine sulphinic acid bo 0.04% by weight (all quantities are based on monomer). an completion of the reaction, the m ~ Yld a pH-value of 2.8.
æX~ME'LE 8 us poly~risation m e continuol~Q perfor~ance of the polymeri a tion re~ ion of Example 1 Fuxxhx~ed the e~#~bed reduction in the amD nts of activatcr in relation to the catch-type procedure.
Tbst A4~xlrat~s .~nom th x e supply vessels (emulsifier, monomer and activator p~Lase), the ~ s were pumped by precision mebering ~umps into a premix1n~ vessel (v~l. 1 litre; oooled to 5 & , intensive acrixtore) and ~ub~eqyen¢1y passed thrcu~h three polymerisation vessels (heatable and ccolable indbperlently of one another).
m e polymerisati~on vessels had a volume of 3 litres.
Admixture w~as obtained by propeller stirrers with a dia~eter of 5 om rotating at 600 rpm.
A,fter 15 hc~rs' operation, a state of equili~rium was reached in the continoDus polymerisation process. `~
The nr~mer throughput amDunted to 1.5 litres of chlorDprene F~r hour, w!hilst the nr~Yxner con~ersion as determlned at the discharge e~d of the third vessel amDunted to 65%.
The ccrao~EdiuQoof activator were determined after 10 hours' equilibrium in the apparatus.
m e acti~a~r consumptions amounted to:
for comparisan:
Continuous procedure batch-type Eu~xa#iure Example 8 a) Example 1) IOB~SOl 0.025 S by ~elght Or rorna~idine sulphinic ucid 0 21 ~ by ~ei8ht oi ionnuaidine ulphi~ic a¢ld E~ple 8 b) Esu~pl- 2) 0 09 ~ by weight f ~2S28 17 ~ br woight Or 0.009 ~ by weight Or anthraquiuone-2-sulpho~lc acld (Na-~alt) 0.017 ~ by welg~t or anthraqulno~--2-~ulphonic acld (Na--a}t) Exa~ple 8 c) E~anple ~) 0.05 ~ by weight Or ~2S208 0 S050% by ~olght Or 0.005 ~ by weight of anthr~qulnone- 0.005 % by ~olght Or 2-sulphonic aold (Na salt) a~thraqul~o~e-2-~ulphonlc ucia (Na-~alt) 0.0011 % by weight oi tor~a~ldlno 0.04 S by ~elght oi sulphinlc acid ror u~idlne sulphinic acid (All qusntities basod on ~ono~or).
~"~ ~
~ ~, ::
~ e A 17 575 - 14 -
Unreacted organlc oo~pQunds ~ay ~e re o~ed by ~toa~
distillatlon, tor e~u ple at 50C and under an ab~oluto pressure ot 20 Torr.
The rollo~lng Esa ples are lntonded to illu~trate tho invention wlthout li~iting It ln any way.
EXAMPLE I
Poly~erlsation acoordin~ to the Drior art To produce the poly er, a ni~ture Or tho rollo~lng co~position was poly~erised under nit~ogen:
Chloroprene 100,00 parts by ~elght n-Dodecyl ~ercaptan 0.25 p~rts by ~eight Phe~othiaslne 0,01 part by ~oight Desalted water 120,00 parts by ~eight Sodiu~ salt Or a disproportionated abietic acid 4.00 parts by ~elght Caustic soda 0.6 p~rt by ~elght Sodium salt ot the oondensatlon product Or napthaleno sulphonic acld and ~on aldohyde 0.6 part by ~eig~t Le A 17 575 - 9 -10~8501 The poly~erisation reaction ~a~ carrlod out at 40C
by running B 1% aqueous ~olution o~ Sor~a idino sulphinic acid continuou41y into the ~isturo.
The reaction was stopped at a nono er oon~or~ion oi ~5~ by r~moving the ~ono~er.
The consu~ption of actiYator a~ounted to 0.21 ~ by welght, ba~ed on the quantlty Or ~ono~or usod, Polymerisation according to Drlor art The procedure was as described ln E~a~plo 1, oscept that the rorma~idine sulphinic acid was roplacod by a 2 ~ aquoous ~olution Or potassiu~ pero~y disulphate containlng 10 %
by woight Or the sodiu~ salt oi aDthraquinone-2-sulphonic acid, the quantity by weight being basod on K2S208.
0.17 % by weig~t Or X2S208 hsd been consu~od by tho tino a mono~er conversion Or 65 % was roached.
Poly~erisation with the activator ~sten a¢cordlDg to tho invention The procedure was as described in E~a plo I, escopt thatO.O~
by weight Or K2S208 and 0.05 ~ by welght o~ anthr~quinone-2-sulphonic acid (sodiu~ salt) wore added to the i~ture.
The poly~erisation reaction co~menced i~mediatoly a~tor the beginning Or the dropwise addition Or tho 1 ~ aqueous rorma~idine sulphinic aold salution, 0.04 % by weight ot ~on~ldlne sulphinlo acid had been consumod by tho ti~e tho ~ono~er con~orsion reaohed ~5f-(All quantitios aro basod on the quantity Or nono er uoed).
Le A ~7 ~75 - 10 -10~8SO~
A mixture of the rollowing composition ~a8 polymorised under nitrogen:
Chloroprene lO0.0 parts by welght Phenothiazone o.005 part by weight n-Dodecyl mercaptan O.lO part by weight Desalted water ~0.0 parts by woight Sodlum salt Or a disproportionated abietic aci~ 2.8 parts by weight ~austic soda 0.5 part by weight Adduct of i-nonyl phenol and lO mole~
o~ ethylene amide 0.5 part by weight Polymerisation wa~ carried out at 50C by running a 2.~% a~ueous ~ormamidine ~ulphinic acld cont$nuous}y into the mi~ture.
The monomer was converted to a level o~ 99%. The consumption of acti~ator amounted to 0.32 % by welght, based on monomer.
~0 EXAMPLE 5 The procedure was as de~cribod in Example 4, escept that 0.05 ~ by weight Or K2~208 and 0.0005 ~ by ~eight oi anthraquinone-2-sulphonic a¢id (~odium salt) were added to the mixture before the beglnning Or the polymerisation reaction.
OoOB % by weight oi rormamidine ~ulphlnic aeid ~a8 required to obtain a mono~er oonYersion Or 99% (all quantitie9 are based on monomer).
Le A 17 57~
1~
~MPLE 1~
Polymerisation according to the Drior art To produce the polymer~ a mixture or the iollo~ing composition W8~ poly~erised under nltrogens Chloroprene 98 0 parts by wolght Methacrylic acid (stablli~ed wlth 50 ppm of ~ydroqulnone methyl ether)2 0 parts by ~el~ht Phenothiazine 0 01 part by weight n-Dodecyl mercaptan 0 20 part by ~eight Desalted w~ter 85 0 parts by ~elght Parafiin sulphonate 3 5 parts by woight~
Adduct of 1 mole Or stearyl alcohol and 20 moles o~ ethylene oside1 0 part by ~oight Conden~atlon product oi naphthaleno sulphonic acld and ror~aldehyde0 3 part by ~elght The reaction was oarrled out at a te perature ln tho range Or irom 45 to 50C A~ter the addltlo~ o~ a 2 5 %
aqueous ror~a~idine sulphinlc acld solutlon, the polynorlsatlon reaction began vigorously and nocossitated inte~sl~o cooling The fonmamidine sulphinio aold solution ~as thon addod dropwise at suoh a rate that the polyaeri~atlon teaperature re~ained in the required range -~; 0 1~ ~ by welght of ior~a ldine ~ulphlnic aold, basod ; on monoaer, had boen consumed by the tiao tho ao~oaor ~o~orslon reached 99 ~0 On co~pletion oi tho roaotion, tho a~turo had ~ p~alue ~ Or 4 0 -~ E~AMPLE 7 The repotitlon oi E~a~plo 6 wlth 0 004 ~ by weight of X2S208 ~nd 0 0004 ~ by woight oi ~nthr~Qul~o~e~ ulphi~lc Le A 17 575 - 12 -.
, .. . . . . .
lllW501 æ id (_odiun~ salt) produced a reduction in ~he ccnsulFtion of fornEm~idine sulphinic acid bo 0.04% by weight (all quantities are based on monomer). an completion of the reaction, the m ~ Yld a pH-value of 2.8.
æX~ME'LE 8 us poly~risation m e continuol~Q perfor~ance of the polymeri a tion re~ ion of Example 1 Fuxxhx~ed the e~#~bed reduction in the amD nts of activatcr in relation to the catch-type procedure.
Tbst A4~xlrat~s .~nom th x e supply vessels (emulsifier, monomer and activator p~Lase), the ~ s were pumped by precision mebering ~umps into a premix1n~ vessel (v~l. 1 litre; oooled to 5 & , intensive acrixtore) and ~ub~eqyen¢1y passed thrcu~h three polymerisation vessels (heatable and ccolable indbperlently of one another).
m e polymerisati~on vessels had a volume of 3 litres.
Admixture w~as obtained by propeller stirrers with a dia~eter of 5 om rotating at 600 rpm.
A,fter 15 hc~rs' operation, a state of equili~rium was reached in the continoDus polymerisation process. `~
The nr~mer throughput amDunted to 1.5 litres of chlorDprene F~r hour, w!hilst the nr~Yxner con~ersion as determlned at the discharge e~d of the third vessel amDunted to 65%.
The ccrao~EdiuQoof activator were determined after 10 hours' equilibrium in the apparatus.
m e acti~a~r consumptions amounted to:
for comparisan:
Continuous procedure batch-type Eu~xa#iure Example 8 a) Example 1) IOB~SOl 0.025 S by ~elght Or rorna~idine sulphinic ucid 0 21 ~ by ~ei8ht oi ionnuaidine ulphi~ic a¢ld E~ple 8 b) Esu~pl- 2) 0 09 ~ by weight f ~2S28 17 ~ br woight Or 0.009 ~ by weight Or anthraquiuone-2-sulpho~lc acld (Na-~alt) 0.017 ~ by welg~t or anthraqulno~--2-~ulphonic acld (Na--a}t) Exa~ple 8 c) E~anple ~) 0.05 ~ by weight Or ~2S208 0 S050% by ~olght Or 0.005 ~ by weight of anthr~qulnone- 0.005 % by ~olght Or 2-sulphonic aold (Na salt) a~thraqul~o~e-2-~ulphonlc ucia (Na-~alt) 0.0011 % by weight oi tor~a~ldlno 0.04 S by ~elght oi sulphinlc acid ror u~idlne sulphinic acid (All qusntities basod on ~ono~or).
~"~ ~
~ ~, ::
~ e A 17 575 - 14 -
Claims (5)
OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A process for the polymerisation of chloroprene which may contain up to 50% weight of a comonomer copolymerisable with chloroprene in an aqueous emulsion in the presence of known surface-active compounds in the alkaline, neutral or acid pH-range wherein the three-component combination of an inorganic peroxy compound, anthraquinone-2-sulphonic acid-alkali salt and formamidine sulphinic acid is used as an activator system.
2. A process as claimed in claim 1, wherein the three-component combination is used in quantities of from 0.02 to 0.6% by weight, based on the monomers used.
3. A process as claimed in claims 1 and 2, wherein the alkali salt of the anthraquinone-2-sulphonic acid and the peroxy compound are added before the beginning of polymerisation whilst the polymerisation reaction is started and controlled with formamidine sulphinic acid.
4. An activator/initiator combination for the polymerisation of chloroprene consisting of 95 to 50% by weight of formamidine sulphinic acid, 4.5 to 25% by weight of an inorganic peroxy compound and 0.5 to 2.5%
by weight of the alkali salt of anthraquinone-2-sulphonic acid.
by weight of the alkali salt of anthraquinone-2-sulphonic acid.
5. An activator/initiator combination as claimed in claim 4, wherein the quantitative ratio of the peroxy compound to the alkali salt is in the range of from 2:1 to 10:1.
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE2627452 | 1976-06-18 | ||
| DEP2627452.2 | 1976-06-18 | ||
| DEP2650342.4 | 1976-11-03 | ||
| DE19762650342 DE2650342C3 (en) | 1976-11-03 | 1976-11-03 | Process for the polymerization of chloroprene |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1088501A true CA1088501A (en) | 1980-10-28 |
Family
ID=25770584
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA280,710A Expired CA1088501A (en) | 1976-06-18 | 1977-06-16 | Process for the polymerisation of chloroprene |
Country Status (5)
| Country | Link |
|---|---|
| JP (1) | JPS534088A (en) |
| CA (1) | CA1088501A (en) |
| FR (1) | FR2393013A1 (en) |
| GB (1) | GB1547318A (en) |
| NL (1) | NL7706658A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3605331A1 (en) * | 1986-02-19 | 1987-08-20 | Bayer Ag | METHOD FOR POLYMERIZING CHLOROPRENE |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2426854A (en) * | 1945-12-15 | 1947-09-02 | Du Pont | Polymerization of chloroprene |
| BE577398A (en) * | 1958-04-10 | |||
| US3344128A (en) * | 1965-04-12 | 1967-09-26 | Phillips Petroleum Co | Thiourea dioxide as reductant in emulsion polymerization |
-
1977
- 1977-06-16 GB GB2521477A patent/GB1547318A/en not_active Expired
- 1977-06-16 CA CA280,710A patent/CA1088501A/en not_active Expired
- 1977-06-16 NL NL7706658A patent/NL7706658A/en not_active Application Discontinuation
- 1977-06-16 JP JP7055377A patent/JPS534088A/en active Granted
- 1977-06-17 FR FR7718743A patent/FR2393013A1/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6154806B2 (en) | 1986-11-25 |
| FR2393013B1 (en) | 1983-12-23 |
| JPS534088A (en) | 1978-01-14 |
| NL7706658A (en) | 1977-12-20 |
| FR2393013A1 (en) | 1978-12-29 |
| GB1547318A (en) | 1979-06-06 |
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