Certain EPDM copolymer/maleic anhydride adducts and thermoplastic elastomers therefrom

Abstract

An adduct of maleic anhydride and an elastomeric copolymer of ethylene, at least one C 3 -C 6 α-olefin, and at least one nonconjugated diene; the adduct having an inherent viscosity of at least one as measured on 0.1 gram of adduct dissolved in 100 milliliters of perchloroethylene at 30° C. and having a gel content less than about 5 percent as measured by weight percent adduct insoluble in boiling tetrahydrofuran at atmospheric pressure after 48 hours. Also, a process of making the adduct and thermoplastic elastomers prepared from the adduct.

What is claimed is:  .[.1. An adduct of maleic anhydride and an elastomeric copolymer of ethylene, at least one C 3  to C 6  α-olefin, and at least one nonconjugated diene; the adduct having an inherent viscosity of at least one as measured on 0.1 gram of adduct dissolved in 100 milliliters of perchloroethylene at 30° C. and having a gel content less than about 5 percent as measured by weight percent adduct insoluble in boiling tetrahydrofuran at atmospheric pressure after 48 hours..]. .[.2. The adduct of claim 1 wherein the elastomeric copolymer is a copolymer of ethylene, propylene, and at least one of a linear aliphatic diene of at least six carbon atoms having one terminal double bond, and a cyclic diene with at least one double bond in a cyclic ring..]. .[.3. The adduct of claim 1 wherein the elastomeric copolymer is a copolymer of ethylene, propylene, and 1,4-hexadiene having an inherent viscosity of at least about 1.5, and the adduct contains about 0.5 to 9 percent by weight maleic anhydride..]. .[.4. The adduct of claim 3 wherein the adduct contains about 1 to 4 percent by weight maleic anhydride and has a gel content less than about 2 percent..]. .[.5. The adduct of claim 1 wherein the elastomeric copolymer is a copolymer of ethylene, propylene, and at least one of an alkylidene bicycloalkene, alkenyl bicycloalkene, bicycloalkadiene, and an alkenyl cycloalkene..]. .[.6. The adduct of claim 5 wherein the nonconjugated diene is 5-ethylidene-2-norbornene, the elastomeric copolymer has an inherent viscosity of about 1.5 to 3.0, and the adduct contains about 0.5 to 9 percent by weight maleic anhydride..]. .[.7. The adduct of claim 1 wherein the elastomeric copolymer is a copolymer of ethylene, propylene, a monoreactive nonconjugated diene, and at least one direactive nonconjugated diene..]. .[.8. The adduct of claim 7 wherein the elastomeric copolymer is a tetrapolymer of ethylene, propylene, 1,4-hexadiene, and 2,5-norbornadiene having an inherent viscosity of about 1.2 to 3.0; and the adduct contains about 0.5 to 9 percent by weight maleic anhydride..]. .[.9. A thermoplastic elastomer obtained by curing 
     
       3. an accelerator having an active hydrogen atom..]. .[.10. The thermoplastic elastomer of claim 9 wherein the adduct is an ethylene/propylene/nonconjugated diene copolymer containing about 0.5 to 9 percent by weight maleic anhydride and the accelerator is at least one of water, mercaptans, thiols, phenols, organic acids, alcohols, and amines..]. .[.11. The thermoplastic elastomer of claim 10 whwerein the copolymer is an ethylene/propylene,5-ethylidene-2-norbornene terpolymer..]. .[.12. The thermoplastic elastomer of claim 10 wherein the copolymer is ana ethylene/propylene/1,4-hexadiene/2,5-norbornadiene tetrapolymer..]. .[.13. The thermoplastic elastomer of claim 10 wherein the copolymer is an ethylene/propylene/1,4-hexadiene terpolymer..]. .[.14. The thermoplastic elastomer of claim 9 wherein the copolymer is an ethylene/propylene/1,4-hexadiene terpolymer having an inherent viscosity of at least 1.5, and said adduct contains about 1 to 4 percent by weight maleic anhydride..]. .[.15. The thermoplastic elastomer of claim 14 wherein said accelerator is at least one of zinc acetate dihydrate, hydrated zinc acetylacetone, and hydrated zinc catecholate..]. .[.16. The thermoplastic elastomer of claim 14 wherein zinc oxide is also present..]. .[.17. The method of preparing an elastomeric adduct containing maleic anhydride, the adduct having a gel content less than about 5 percent as measured by weight percent adduct insoluble in boiling tetrahydrofuran at atmospheric pressure after 48 hours consisting essentially of 1. mixing A. an elastomeric copolymer of ethylene, at least one C 3  to C 6  α-olefin, and at least one nonconjugated diene, the copolymer having an inherent viscosity of at least one as measured on 0.1 gram copolymer dissolved in 100 milliliters of perchloroethylene at 30° C., and   B. maleic anhydride, and d     2. heating the mixture to a temperature of about 225° to 350° C..]. .[.18. The method of claim 17 wherein the copolymer is a copolymer of ethylene, propylene, and at least one of a linear aliphatic diene of at least six carbon atoms having one terminal double bond, and a cyclic diene with at least one double bond in a cycle ring..]. .[.19. The method of claim 17 wherein the copolymer is an ethylene/propylene/1,4-hexadiene terpolymer having an inherent viscosity of at least 1.5..]. .[.20. The method of claim 17 wherein the copolymer is an ethylene/propylene/1,4-hexadiene/2,5-norbornadiene tetrapolymer having an inherent viscosity of about 1.2 to 3.0..]. .[.21. The method of claim 17 wherein the copolymer is an ethylene/propylene/5-ethylidene-2-norbornene terpolymer having an inherent viscosity of 1.5 to 3.0..]. .[.22. A method of preparing a thermoplastic elastomer, said method comprising the following steps:   1. mixing A. an adduct of maleic anhydride with an ethylene/propylene/1,4-hexadiene terpolymer, the proportion of maleic anhydride being about 1-4 weight percent of the adduct; the gel content of the adduct being less than about 2 weight percent as measured by the proportion of adduct insoluble in boiling tetrahydrofuran at atmospheric pressure for 48 hours; and the inherent viscosity of the adduct being at least 1 as measured on 0.1 gram of adduct dissolved in 100 ml. of perchloroethylene at 30° C.; and   B. an amount of at least one zinc salt selected from the group consisting of zinc acetate dihydrate, hydrated zinc acetylacetone, and hydrated zinc catecholate effective to cure the adduct;     2. exposing the resulting mixture to at least one accelerator selected from the group consisting of water, mercaptans, phenols, organic acids, alcohols, and amines; and   3. heating the exposed mixture for a sufficient time to cure the adduct..]. .Iadd. 23. The method of preparing an elastomeric adduct containing maleic anhydride, the adduct having a gel content less than about 5 percent as measured by weight percent adduct insoluble in boiling tetrahydrofuran at atmospheric pressure after 48 hours consisting of   1. mixing A. an elastomeric copolymer of ethylene, at least one C 3  to C 6  α-olefin and at least one nonconjugated diene selected from 1,4-hexadiene, 5-alkylidene-2-norbornenes, and a combination of either of the above with at least one of 2,5-norbornadiene and 1,7-octadiene, the copolymer having an inherent viscosity of at least one as measured on 0.1 gram copolymer dissolved in 100 milliliters of perchloroethylene at 30° C., and   B. maleic anhydride, and     2. heating the mixture to a temperature of about 225° to 350° C. .Iaddend..Iadd. 24. The method of claim 23 wherein the copolymer is an ethylene/propylene/1,4-hexadiene terpolymer having an inherent viscosity of at least 1.5. .Iaddend..Iadd. 25. The method of claim 23 wherein the copolymer is an ethylene/propylene/1,4-hexadiene/2,5-norbornadiene tetrapolymer having an inherent viscosity of about 1.2 to 3.0. .Iaddend..Iadd. 26. The method of claim 23 wherein the copolymer is an ethylene/propylene/5-ethylidene-2-norbornene terpolymer having an inherent viscosity of at least 1.5 to 3.0. .Iaddend..Iadd. 27. The method of preparing a thermoplastic elastomer, said method comprising the following steps:   1. mixing A. an adduct of maleic anhydride with an ethylene/propylene/1,4-hexadiene terpolymer, the proportion of maleic anhydride being about 1-4 weight percent of the adduct; the gel content of the adduct being less than about 2 weight percent as measured by the proportion of adduct insoluble in boiling tetrahydrofuran at atmospheric pressure for 48 hours, and the inherent viscosity of the adduct being at least 1 as measured on 0.1 gram of adduct dissolved in 100 ml. of perchloroethylene at 30° C.; and,   B. an amount of at least one zinc salt selected from the group consisting of zinc acetate dihydrate, hydrated zinc acetylacetone, and hydrated zinc catecholate effective to cure the adduct;     2. exposing the resulting mixture to at least one accelerator selected from the group consisting of water, mercaptans, phenols, organic acids, alcohols, and amines; and   3. heating the exposed mixture for a sufficient time to cure the adduct. .Iaddend.