Patent Publication Number: US-3876590-A

Title: Cross-linked polymer of an epihalohydrin and a process for producing the same

Description:
United States Patent [1 1 Shimogawa et al.  
 [ Apr. 8, 1975 21 Appl. No.: 401,873  
 [30] Foreign Application Priority Data Oct. 5, l972 Japan 47-l000l6 Nov. l, 1972 Japan 47-l0973l [52] US. Cl 260/79; 260/2 A; 260/23 R;  
  260/23 S; 260/23 H; 260/37 R; 260/79; 260/795 C; 260/793; 260/874; 260/887;  
  260/897 R [5 l] Int. Cl C08g 23/00 [58] Field of Search 260/79, 79.5 C, 2 A, 793, 260/887. 897 R, 874  
 [56] References Cited UNITED STATES PATENTS 3,700,650 10/1972 Hani et al. 260/2 A 3,708,461 1/1973 Karastu et al 260/79 E 2.0 U )1 1 5 X V LL] 3 O 0.5  
 Primary Examiner-Melvyn l. Marquis Attorney, Agent, or FirmSherman &amp; Shalloway [57] ABSTRACT A cross-linked polymer of an epihalohydrin prepared by heating a polymer of an epihalohydrin in the presence of a metal salt of ethylene-bisdithiocarbamic acid having the following formula:  
 wherein symbol M stands for a divalent metal atom in the amount of from 0.1 to l0 parts by weight based on 100 parts by weight of the polymer of epihalohydrin, said epihalohydrin polymer being selected from the group consisting of polymers of epihalohydrin, copolymcrs of epihalohydrin with alkylene oxides, and mixtures containing other sulphur vulcanizable rubbers of not more than 50 percent by weight based on the weight of the mixture of the sulphur-vulcanizable rubbers with these homoor co-polymers, and a process for preparation said polymer.  
 5 Claims, 2 Drawing Figures A RUBBER COMPOSITION OFA POLYMER OF AN EPl HALOHYDORIN TIME (mm) CROSS-LINKED POLYMER OF AN EPIHALOHYDRIN AND A PROCESS FOR PRODUCING THE SAME The present invention is concerned with a process of cross-linking epihalohydrin polymers, copolymers of an epihalohydrin and an alkylene oxide, and mixtures with other sulphur-vulcanizable rubbers containing more than 50 percent by weight of these polymers and copolymers. Whenever epihalohydrin polymer&#34; is used in describing the subject invention. it is to be understood that epihalohydrin copolymer with alkylene oxide&#34; and mixtures of more than 50 percent by weight of epihalohydrin polymers and/or epihalohydrin copolymers with alkylene oxide with other sulphur-vulcanizable rubbers may be substituted therefor, with the obvious exceptions of specific examples and the like.  
  Epihalohydrin polymers assume a variety of configurations depending upon the type of the polymerization catalyst used. Particularly polymers ofa high molecular weight and which are amorphous or nearly amorphous are vulcanized, (that is, cross-linked) to be used as a special rubber having useful physical properties. Known processes of producing cross-linked epihalohydrin polymers include the use of polyamines, polyamine hydrochlorides, polyamine carbamates and the like; a process of subjecting polymers to the action of a substance selected from the group consisting of sulphur, dithiocarbamate, thiuram sulfide and thiazole-in the presence of an amine (U.S. Pat. No. 3,026,305); a process involving the use of Z-mercaptoimidazoline or 2-mercaptopyrimidine (U.S. Pat. No. 3,341,491); etc.  
  The cross-linking reaction of epihalohydrin polymers is said to be caused by the reaction of halogen in the side chain. Obviously the above methods differ from the cross-linking reaction sulphurvulcanizable rubbers in general.  
  The present invention relates to a cross-linked polymer of an epihalohydrin prepared by heating an epihalohydrin polymer, copolymer, or mixture thereof with sulphur-vulcanizable rubbers in the presence ofa metal salt of ethylenebisdithiocarbamic acid having the following formula wherein symbol M stands for a divalent metal atom in an amount of from 0.1 to 10 parts by weight based on 100 parts by weight of the polymer of epihalohydrin. The epihalohydrin polymer is selected from the group consisting of: polymers of epihalohydrin; copolymers of epihalohydrin with alkylene oxides; and mixtures of not more than 50 percent by weight based on the weight of the mixture of other sulphur-vulcanizable rubbers with these homoor copolymers.  
  In the proposal of US. Pat. No. 3.026,305, there is described the utilization of straight chain dithiocarbamates being represented by the following formula S S H H N-C-S-Metal-S-C-N in the presence of an amine or an amine and sulphur. The dithiocarbamates concerned are widely used as vulcanizing agents (or vulcanization acceleraters) and are well known for use in conjunction with sulphur or sulphur releasing compounds in vulcanizing the usual sulphur-vulcanizable rubbers. In order to obtain satisfactory results in the presence of an amine, vulcanization of a polymer of an epihalohydrin is conducted using the aforesaid known vulcanizing agents in the presence of sulphur and it is demonstrated that this vulcanizing agent alone will not bring about vulcanization results capable of utilization.  
  The present inventors have devoted themselves to studying the vulcanization of an epihalohydrin polymer and discovered that the metal salt of ethylene-bisdithiocarbamic acid being represented by the aforesaid formula (conventionally well known and used as the active component of agricultural-horticultural fungicides) could exhibit, by itself, excellent vulcanization effects on the aforesaid polymers, or preferably can be used in the presence of an oxide or hydroxide of metals of Group &#34;A of the Perodic Table.  
  Explanation will be given in more detail by referring to drawings. It was entirely unexpected and surprising result that the aforesaid straight chain dithiocarbamates, which are known vulcanizing agents, exhibit, by themselves, vulcanization effects on the usual rubber, while not showing any vulcanization effects capable of utilization on the polymers of epihalohydrin. ln sharp contrast, the aforesaid known fungicidal active component used in the present invention does not show any vulcanization effects capable of utilization on the usual rubber while showing excellent vulcanization effects on the polymers of epihalohydrin.  
  In the present invention it was further found that the co-presence of the oxide or hydroxide of a metal from Group 11A of the Periodic Table increased the rate of vulcanization and at the same time, improved heat resistance of the cross-linked product.  
  Furthermore, when a cross-linked product of an epihalohydrin polymer was conventionally produced, its vulcanization vessel, such as a molding die, vulcanization can, and so on, was markedly corroded and there was a long felt need for the inhibition of corrosion or a cross-linking method not accompanied with corrosion. According to the present invention, it has been also discovered that the co-presence of a certain amine or amine carboxylate can bring about an increase of the cross-linking rate at the same time, make it possible to inhibit die corrosion to a remarkable degree.  
  Cross-linked blends of an epihalohydrin polymer with a variety of other sulphur-vulcanizable rubbers are interesting as materials with useful modified physical properties and it was found that according to the present invention, it was made easier to cross-link the aforesaid blends.  
  Thus, the present invention is designed to provide a novel cross-linked polymer from an epihalohydrin polymer.  
  The second object of the present invention lies in providing a cross-linking method having reduced die corrosion and producing cross-linked products of an epihalohydrin polymer.  
  The third object of the present invention lies in providing a vulcanizing method easily capable of crosslinking blends of epihalohydrin polymers with unsaturated rubbers.  
 Sulphur-vulcanizable rubber (SBR) composition Present invention Comparison SBR Zineb Stearic acid FEF carbon MB MgO  l 40 l s l (Note I:  
 SBR Styrcnc-hutadicnc rubber (JSR-l778) MB Z-Mercaptohenzothiazole (antioxidant) &#39;l&#39;l&#39; &#39;lctramcth lthiuram disullidc Zineb Zinc cth lenc-biodithiucarhamate PZ Zine dimcth ldithiocarbarnatc FEF carbon A product of &#39;l&#39;okyo Denkyoku Company Rubber composition of a polymer of an epihalohydrin Present invention Comparison C HC 100 Zineb Tin stearate FEF carbon M B MgO (Note): CHC Ethylene oxide-cpichlorohydrin l:l Copolymcrizctl ruhhcr (a product of Osaka Soda Co., Ltd.)  
  The results of FIG. 1 are indicative of the fact that PZ does not exhibit any vulcanization effect capable of utilization in&#39; the aforesaid rubber composition of the epihalohydrin polymer whereas Zineb exhibits excellent vulcanization effects in the composition concerned. The results of FIG. 2 are indicative of the fact that PZ exhibits vulcanization effects in the aforesaid SBR composition whereas zineb does not exhibit any vulcanization effect capable of utilization in the composition concerned.  
  The experimental results demonstrate the fact that the chain dithiocarbamate and cyclic dithiocarbamate differ from each other in vulcanization characteristics.  
  The metal salts of ethylene-bisdithiocarbamic acid, used in the present invention include barium, zinc, copper, cadmium lead salt, iron, nickel, manganese, etc. Particularly preferred are zinc and lead salts.  
  in the present invention, in addition to the metal salts, the epihalohydrin polymer can be incorporated with at least one accelerator selected from the group consisting of oxides and hydroxides of Group IlA metals of the Periodic Table, sulphur, thiuram sulfide, morpholine disulfide, secondary amine, tertiary amine,  
 guanidines and monoor di-carboxylates of these amines.  
  The above thiuram sulfide is a compound presented by the general formula in which R stands for hydrogen, an alkyl, a cycloalkyl or a polymethylene group with 2 Rs attached to the same nitrogen being connected to form a ring, but in no case 2 Rs attached to the same nitrogen being both hydrogen, and is an integer not smaller than 1.  
  Specific examples of these compounds are tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetrabutylthiuram disulfide, pentamethylenethiuram disulfide, tetramethylthiuram tetrasulfide, pentamethylenethiuram tetrasulfide, etc.  
  Useful Group A metal oxides or hydroxides include magnesium oxide, calcium oxide, barium oxide, magnesium hydroxides calcium hydroxide and barium hydroxide. Particularly preferred is magnesium oxide.  
  In the present invention, amines or amine carboxylates can be used, but amine carboxylates are preferred. Useful amines, are secondary or tertiary amines represented by R- NH, RN, or guanidines. Preferred amine carboxylates are those produced from monobasic carboxylic acids and secondary or tertiary amine salts being represented by RCOONH R RCOONHR&#39;}; and dibasic carboxylic acids and secondary or tertiary amine salts being represented by R&#34; H NOOR-R&#39; COONH R&#34; and R HNOOC-R COONHR&#34; In the above formula R Nl-l, R N, it is preferred that R should be a group selected from alkyl groups with 4-8 carbons, alkenyl groups with 4-8 carbons, cyclohexyl groups, methylcyclohexyl groups and ethylcyclohexyl groups. It is not necessarily required that R should be all the same. Further, in the aforesaid formulae RCOONH- R&#39;Q R&#39;COONHR&#34; it is preferred that R should be a group selected from alkyl or alkenyl groups with 1-11, preferably 3-8, carbons; phenyl groups; tolyl groups; phenylvinyl groups; CH O- COCH=CH groups; C H OCOCH=CH groups; C H OCOCH=CH groups; and C,H,,OCOCH%H- groups. R&#34; is selected from alkyl or alkenyl groups with l-8 carbons; cyclohexyl groups; methylcyclohexyl groups and ethylcyclohexyl groups.  
  As dibasic carboxylic acids, there can be used those in which R is a methylene chain of 2-8 carbons, such as succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid; or maleic acid, fumaric acids, phthalic acid and so on. The amine used in forming a salt with dibasic carboxylic acid is the same as in the case of monobasic acids.  
  Examples of guanidines include, diphenylguanidine, diorthotolylguanidine, orthotolylbiguanidine and the like.  
  Examples of epihalohydrin polymers to be crosslinked in the present invention include homopolymers of epichlorohydrin, epibromohydrin, epiiodohydrin, methylepichoro hydrin and their copolymers, and copolymers of the above epihalohydrins with alkylene oxides, such as ethylene oxide, propylene oxide, butyiene oxide, styrene oxide, phenylglycidyl ether, allyl glycidyl ether, butylglycidyl ether and so on. These polymerized products can be produced using a variety of catalysts, but the cross-linking method of the present invention can be put in practice regardless of the process for the production of polymers. I  
  Examples of other sulphur-vulcanizable rubbers capable of being blended with the aforesaid polymers to carry out the cross-linking reaction include natural rubber, styrene-butadiene rubber, butadiene rubber, isoprene rubber, isoprene-isobutylene rubber, acrylonitrile-butadiene rubber, ethylene-propylene-diene rubber, propylene oxide-allylglycidyl ether copolymer and so on. These rubbers are used in and amount of not more than 50 percent by weight based on the weight of the mixture.  
  In the present invention, the amount of the aforesaid metal oxides, hydroxides, sulphur, amines or carboxylates thereof and sulfides that can be used is suitably varied, but in the case of the said metal oxides, hydroxides and amines or their salts, it is 0.1 20 parts by weight, preferably 1 10 parts by weight and most preferably 1 7 parts by weight, based on 100 parts by weight of the epihalohydrin polymer, whereas in the case of the sulphur and sulfides, it is about 0.05 5 parts by weight based on 100 parts by weight of the epihalohydrin polymer.  
  The mixing of these vulcanizing agents and accelerators with polymers can be conducted by any conventionally known means such as a mixing roll, kneader, Banbury mixer and so on. It is also possible to add them to the solution of the epihalohydrin polymer. Furthermore, there can be incorporated other known components used for the production of cross-linked molded products, such as carbon; inorganic fillers, such as silica, silicate, calcium carbonate, magnesium carbonate and so on; lubricants; plasticizers, softeners, stabilizers, antioxidants, flame resistant agents, pigments and the like. The compounding of the cross-linking agent and other ingredients of the present invention can be conducted in any order.  
  The most preferred cross-linked polymer in the present invention is across-linked polymer of an epihalohydrin prepared by heating a an epihalohydrin polymer in the presence of a metal salt of ethylene-bisdithiocarbamic acid having the following formula II OH -JiH-O-S 1 M CH -HH-- wherein the symbol M stands for a divalent metal atom selected from the group consisting of Pb and Zn in the amount of from 0.1 to parts by weight based on 100 parts by weight of the epichalohydrin polymer; 0.1 parts by weight based on 100 parts by weight of the epihalohydrin polymer of magnesia; at least one member selected from the group consisting of 0.05 5 parts by weight based on 100 parts by weight of the epihalohydrin polymer of sulphur, thiuram disulfide, thiuram tetrasulfide and morpholine disulfide and 0 7 parts by weight based on 100 parts by weight of the epihalohydrin polymer of C, C carboxylates of aliphatic or alicyclic secondary or tertiary amines. The epihalohydrin polymer is selected from the group consisting of: poly(epich1orohydrin): copolymers of epichlorohydrin and ethylene oxide; copolymers of epichlorohydrin and propylene oxide; and mixtures containing other sulphur-vulcanizable rubber present in not more than 50 percent by weight based on the weight of the mixture of the sulphur-vulcanizable rubbers with said homoor copolymers.  
  1n the present invention, the cross-linking reaction can be carried out by heating these mixtures usually at a temperature of 120C or more, for instance, at a temperature ranging from 120 to 200C. The reaction time usually takes 5 60 minutes, but with the temperature elevated a, shorter reaction time will be required. For hot molding of the product, there can be used all heating systems of direct or indirect heating. Examples are by means of press d&#39;ie molding, extrusion or injection molding and continuous heating involving the use of an oil bath, sand bath and so on. It is possible to conduct so-called after-care with a view to improving the physical properties of vulcanized products.  
  The most suited embodiment in the process of the present invention is a process for production of a crosslinked polymer of an epihalohydrin, characterized by heating a polymer of ethylene-bisdithiocarbamic acid having the following formula -ma-g- -s wherein the symbol M stands for a divalent metal atom in the amount of from 0.1 to 10 parts by weight based on 100 parts by weight of the epihalohydrin polymer and l 7 parts by weight based on 100 parts by weight rubbers with these homoor co-polymers.  
  Some embodiments of the present invention will be explained hereinafter by way of Example. The amounts of compositions in the Examples are all based on weight unless otherwise specified. The following is the general process for the production of vulcanized products in the Examples. Using open rolls with the front rolls maintained at C., and the rear rolls at C., the cross-linking agent and other compounding agents (in the amounts clearly described in the Examples with regard to parts of the polymer) were blended together to produce a compound. The compound so obtained was heated and applied with pressure at for 30 minutes under 100 kg/cm to mold sheet-like samples, whose physical properties were measured.  
 Examples 1 and 2 Examples 1 and 2 relate to cross-linking epichlorohydrin homopolymer rubber and epichlorohydrinethylene oxide copolymerized rubber with zinc -ethylenebisdithiocarbamate alone. The comparative Examples are indicative of the results of cross-linking the above rubber with zinc tetramethyldithiocarbamate. The compounds having the following compositions, were produced according to the above general method and vulcanized by means of a die press at 155C. for 30 minutes.  
 Compositions Compositions-Continued Examples Comparative Examples Example 7 Example 8 Example 9 Example l l NBC l l v 7 7 7 CHR* 100 100 g I I I I CHC*- 100 100 SI-Zfl l l l E82 7 NBC l 1 1 l 7 FEF-carhon*&#34; 40 40 40 40 EB EBZ* 2 2 pzh 2 2 Physical properties of vulcanized U Physical properties of vulcanized pmduc&#39;b for 30 minutes products at l55 C for 30 minutes TB &#39;66 I50 154 I65 &#34;n3* l 90 43 5g &#34;a? g? i? EB* 1000 I000 1300 Not H 66 90 70 66 vulcanized 1 5 PS*&#39;&#34; 28 30 54 H*&#34; 66 63 60 &#34;A product of Goodrich company. epichlorohytlrin homopolymcrizud ruhhen H \drin No, ltll) A product of (ioodrich comp-an upichloroh drinelhylenc oxide copolymerized 7 FEE-carbon Examples ll, l2, l3 and l4 The following are examples for vulcanization of epichlorohydrin-ethylene oxide copolymerized rubber by using a variety of ethylene-bisdithiocarbamates in conjunction with thiuram disulfide and&#39;magnesia.  
 Zinc tutramclh ldithiocnrbamatc Strength at a time of breakdown. lag/cm composltlons &#34;Elongation percentage at a time of breakdown &#39;4 &#34;&#34;Permancnt elongation percentngc &#39;4 7 ,Hmdnmhshmc A Example ll Example 1. Example l3 Example l4 CHC&#34; 100 ;r 2 H I, 1! Examples 3, 4. 5 and 6 FEF-carbon*&#34; 40 I ,1 I, H The following are examples for vulcanization of epi- 3O MgO 5 *1? H H 1&#39; chlorohydnn rubber in the system wherein magnesia gin; l was added to a variety of ethylene bisdithiocarbamates. p 3  
  EB-Cu*&#34; 2 EB-Mn*&#34;&#34; 2 Com ositions p 35 Physical properties of vulcanized products at 155C. for minutes Example 3 Example 4 Example 5 Example 6 100% Mod*&#34; 23 10 3| CHR&#34; I00 TB I4] I33 I01 l5l 5r 2 EB 640 750 I000 680 FEF-carhon*-&#34; 4 40 H 70 73 65 72 MBMR I I, n Mgo 2 &#39;l&#39;ctramethylthiuram disullidc EB-Cd*&#34;&#39; 2 *Coppcr cthylcne-bisdithiocarhamate EB-ZH; 2 *&#34;l0()&#39;.; modulus. kg/em EB-Mn*&#34;&#34; 2 EB-Ph*&#34; 2 Examples 15, 16 and 17 Physical properties of vulcanized The following are examples showing the vulcanizas 1 0 r Pmduu C M tion results of eplchlorohydrm-ethylene oxide copoly- TB 130 37 153 135 merized rubber by using a variety of sulfides in con- EB 8610 695 845 8 90 junction with zinc ethylene-bisdithiocarbamate. PS 20 l7 l6 6 H 66 72 66 66 Compositions &#39;LuhricanL tin stenrate &#34;AntioxidunL 2-mcrcaptohenzothiazolc Example 15 Example Example 17 *Cadmium ethylunu-hisdithiocarhamatc 0 &#34;&#34;Manganusc cthylcnc-hisdithiocarhaman: CH0 I00 &#34;&#34;Lcad cthylenc-hisdithiocarbamate STZn*&#34; 2 FEF-carbon 40 MB klr&#39;i l I! I! M o 5 I! I! Examples 7, 8, 9 and 10 5 4 n H TBT l The following are examples for vulcanizatlon of ep1- t-al 1 chlorohydrin-ethylene oxide copolymerized rubber by 6 R** l I l e u n v 0 usmga var ety of ethylene bisdithlocarbamates In con Physical properties of vulcanized uncnon with sulphur and magnesia. products at 155C. x 30 minutes Compositions 100% Mod. 40 54 49 TB I45 122 I23 EB 410 Example 7 Example 8 Example 9 Example 10 H 74 38 CHCflq I00 100 &#34;&#34;Tclrahutylthiuram disulfidc I l l l &#34;Dipcntamcthylcnethiuram tctrasulfide 40 40 40 40 &#34;&#39;Morpholinc disulfidc Sehacid acid* Examples 1 27 Compositions-Continued I Ex. Ex. Ex. Ex. The following are examples showing the results of 28 29 30 31 cross-linking epichlorohydrm rubbers by adding a vanb ety of amines or amine-carboxylates to the vulcanizalsophthafic acidw 3 tion system using ethylene-bisdithiocarbamate. DIPA 3 Compositions Ex. Ex. Ex. Ex. Ex. Ex. Ex. Ex. Ex. Ex. l8 I9 2] 22 23 24 25 26 27 CHC I00 I00 I00 I00 I00 I00 I00 CHR I00 I00 I00 St Zu* 2 2 2 2 2 2 2 2 2 2 FEF carbon 40 40 40 40 -10 40 40 40 40 40 MB*&#34; l I l, w l I l 0.5 l l NBC I 0.5 l i TH&#34; l I I I I I 0.2 0.2 0.2 0.2 MgO 5 5 5 5 5 5 5 5 5 5 EBZ 2 2 I 2 2 2 2 2 EB-Mn*&#34;&#34; 2 2 DCHA* 5 DT I C aproic acid*&#39;-&#34; DCHA 3 5 Cinnamic acid*&#39;-&#34;&#34; DCHA 5 Cinnamic ucid*&#39;-&#34; DIPA 3 5 Methylmaleic acid DIPA 3 Butyric z1cid*&#39;-&#39;&#34; DBA 3. Sorhic llCltI DCHA 3 Sorhic acid*&#39; TE&#39;A 3 Physical properties of vulcanized products at 155T. for 30 minutes 10071 Mod. 39 I 26 40 38 39 35 38 I 39 TB I3] I21 Il0 I20 I19. I22 98 I25 I23 12] EB 4 I 0 430 490 470 480 510 350 580 430 440 H 76 76 73 76 76 75 73 76 76 Physical properties after hot aging for 7 days at [50C. (gear oven) I007: Mod. 83 76 73 75 78 XI 74 79 82 XI TB I04 92 87 93 r 90 I05 I06 I I3 I15 EB I30 ll5 I20 I I5 I I0 I20 80 I40 I50 H 84 84 80 83 83 X4 84 82 82 83 &#34;-&#34;-&#39;I)ic \clohex l amine *Diurlhuluhlgunnidinc *&#39;-&#34;l&#39;)ic clohe&#39; lnmine-capromc &#39;3clohcxylnmine-einnumate supmp luminc-cinnnnmte I so rup vlaminc-moth lmnlculc &#34;I)ihut \lnminc-hul rate *&#39;-&#39;&#34;l)iisuprup Inminc-surhmc &#34;&#34;I&#39;riclhylnminc-surhanc Examples 28 29 30 and 31 50 Physical properties of vulcanized products at C. for 30 minutes The following are examples showing the results of cross-linking epichlorohydrin rubbers by adding amine 1 3i 32 as salts of dibasic acid to the vulcanization system using 53 430 490 420 430 cthylenebisdithiocarbamate. I 55 H 75 74 76 75 *&#34;Dicyclohcxyluminc-fumarate &#34;Tricthylumine-adipulc composlnons *Dicyclohcxylaminoschucatc EX- EX. EX EX. Diisopropylamine-isophthzilatc 28 29&#39; 30 31 CHC*&#34;&#39; I00 I00 i 100 60 CHR*&#39; I00 St-Zn 2 7 2 2 FEF-carbon*&#34; 40 40 4(1) 40 M 1 1 Exam les 32, 33 and 34 s. 0.2 0.2- 0.2 0.2 p gg 2 g g I 65 The following are examples showing the results of \Fumflric vulcanizing mixtures of epichlorohydrin and ethylene DC H A W 3 oxide copolymerized rubber and butadiene rubber in $82 3 the vulcanization system using ethylene-bisdithiocarbamat e.  
 Compositions Compositions-Continued Example 32 Example 33 Example 34 Example 33 CHC*&#39;- so 5 155C. for 30 minutes BRQUL&#39;I I! I! 5V3 (143 3007: Mod*&#34; 92 St-Sn 0.8 TB 153 MB l EB 550 MgO 5 H 7s l Degree of EB-Mn* 4 l0 swelling +142 EB-Ph* 4 EBZ 4 &#34;300&#39; modulus. kg/cru&#34; *&#34;lmmcrscd in toluene of C for 24 hours. Weight increased rate Physical properties of vulcanized 1 what we clfnm ls:  
  products at 155C, for minute 5 1. A cross-linked polymer of epihalohydrin prepared TB H x I by heating at 120 to 200C. a polymer of an epihalohy- EB 3: :6 drin in the presenceof a metal salt of ethylene-bisdithi- H 78 76 77 ocarbamlc acld having the following formula:  
 *Polyhutadicnc rubhcr BR-(ll (a product olJupan Synthetic Rubber Company) &#34;Lubricant. slcaric acid Examples and 36 The following are examples showing the results of vulcanizing mixtures of epichlorohydrin homopolymer rubber and natural rubber with lead ethylene-bisdithiocarbamate.  
  The following is indicative of the results of vulcanizing epichlorohydrin-ethylene oxide copolymerized rubber and natural rubber.  
 Compositions Example 33 CHC 90 NR=BITT St-Zn*&#34; 1 FE B-carbon*&#34;&#39; 50 MB=H3 l MgO 5 EB-Pb 4 Physical properties at wherein M is a barium, zinc, copper, cadmium, lead, iron, nickel or manganese ion in the amount of from 0.1 to 10 parts by weight based on parts by weight of the polymer of epihalohydrin, said epihalohydrin polymer being selected from the group consisting of polymers of epihalohydrin, copolymers of epihalohydrin with alkylene oxides, and mixtures containing the polymers or the copolymers and sulphur-vulcanizable rubbers selected from at least one of the group consisting of natural rubber, styrene-butadiene rubber, butadiene rubber. isoprene rubber, isoprene-isobutylene rubber, acrylonitrile-butadiene rubber, ethylenepropylene-diene rubber and propylene oxide-allyl glycidyl ether copolymerized rubber, and present in not more than 50% by weight based on the weight of the mixture of the sulphur-vulcanizable rubbers with the polymers or copolymers.  
  2. A cross-linked polymer according to claim 1 in which in addition to said metal salts of ethylene-bisdithiocarbamic acid, said epihalohydrin polymer is incorporated with at least one accelerator selected from the group consisting of oxides and hydroxides of Group llA metals of the Periodic Table, sulphur, thiuram sulfide, morpholine disulfide, secondary amines, tertiary amines, guanidines and monoor di-carboxylates of these amines, with the proviso that: in the case of said metal oxides, said metal hydroxides and said amines or salts thereof they are contained in the amount of 0.1 20 parts by weight based on 100 parts by weight of the epihalohydrin polymer; and in the case of said sulphur and said sulfides, they are contained in the amount of 0.05 5 parts by weight based on 100 parts by weight of the epihalohydrin polymer.  
  3. A cross-linked polymer according to claim 1 in which said epihalohydrin is epichlorohydrin and said alkylene oxide is a member selected from the group consisting of ethylene oxides and propylene oxides.  
  4. A cross-linked polymer of an epihalohydrin prepared by heating at to 200C. a polymer of epihalohydrin in the presence of a metal salt of ethylene-bisdithiocarbamic acid having the following formula:  
 CH -N&#39;H- wherein symbol M stands for a divalent metal ion selected from the group consisting of Pb and Zn in the amount ,of from 0.1 to parts by weight based on 100 parts by weight of the polymer of epihalohydrin; 0.1 parts by weight based on 100 parts by weight of the polymer of epihalohydrin of magnesia; at least one member selected from the group consisting of 0.05  
 - 5 parts by weight based on 100 parts by weight of the 15 polymer of epihalohydrin of sulphur, thiuram disulfide, thiuram tetrasulfide and morpholine disulfide and O 7 parts by weight based on 100 parts by weight of the polymer of epihalohydrin of C C carboxylates of aliphatic or alicyclic secondary or tertiary amines, said 5. A process for production ofa cross-linked polymer of an epihalohydrin, characterized by heating at 120 to 200C. a polymer of an epihalohydrin in the presence of a metal salt of ethylene-bisdithiocarbamic acid having the following formula:  
 wherein M is a barium,&#39;zinc, copper, cadmium, lead, iron, nickel, or manganese ion in the amount of from 0.1 to 10 parts by weight based on parts by weight of the polymer of epihalohydrin and l 7 parts by weight based on 100 parts by weight of the polymer of epihalohydrin of C C carboxylates of aliphatic or alicyclic secondary or tertiary amines, said epihalohydrin polymer being selected from the group consisting of polymers of epihalohydrin, copolymers of epihalohydrin with alkylene oxide and mixtures containing the polymers or copolymers and sulphur-vulcanizable rubbers selected from at least one of the group consisting of natural rubber, styrene-butadiene rubber, butadiene rubber, isoprene rubber, isoprene-isobutylene rubber, acrylonitrile-butadiene rubber, ethylene-propylene-diene rubber and propylene oxide-allyl glycidyl ether copolymerized rubher. and present in not more than 50 percent by weight based on the weight of the mixture of other sulphurvulcanizablc rubbers of these polymers or copolymers.