Metal oxide paste dispersions and use as curing agents

Claim 2

THE PROCESS FOR CURING HALOPRENE POLYMERS WHICH COMPRISES INCORPORATING INTO THE POLYMER STOCK UP TO ABOUT 12 PARTS BY WEIGHT BASED ON 100 PARTS BY WEIGHT OF POLYMER, OF A PASTE CO-DISPERSION CONSISTING ESSENTIALLY OF FROM ABOUT 50% TO ABOUT 80% BY WEIGHT OF A MIXTURE OF FROM ABOUT 30 TO ABOUT 80 PARTS BY WEIGHT OF MAGNESIUM OXIDE AND FROM ABOUT 10 TO ABOUT 60 PARTS BY WEIGHT OF ZINC OXIDE, THE OXIDES HAVING AN AVERAGE PARTICLE SIZE OF UP TO ABOUT 10 MICRONS, A NON-AQUEOUS LIQUID VEHICLE AND AN OIL-SOLUBLE OR OIL-DISPERSIBLE SURFACE ACTIVE AGENT, AND HEATING THE MIXTURE TO EFFECT CURING OF THE POLYMER.

Claim 3

The process of claim 1 wherein the polymer is a chloroprene.

Claim 4

The process of claim 1 wherein from about 0.2 to about 12 parts by weight of the paste is incorporated into about 100 parts of the chloroprene polymer stock.

Claim 5

The process of claim 1 wherein the paste co-dispersion consists essentially of a mixture of from about 30 to 80 parts by weight of fine particle size magnesium oxide, from about 10 to 60 parts by weight of fine particle size zinc oxide and from about 1 to 5 parts by weight of an oil-soluble or oil-dispersible surface active agent having a hydrocarbon chain containing from about 2 to about 75 carbon atoms in a mineral oil vehicle.

Claim 6

The process of claim 1 wherein there is also included in the paste co-dispersion, from about 1 to 5 parts by weight of a modifying agent consisting of waxes, metallic soaps, and clay.

Claim 7

The process for curing haloprene polymers which comprises incorporating into the polymer stock, from about 0.2 to 12 parts by weight based on 100 parts by weight of the polymer, of a paste co-dispersion comprising from about 50% to about 80% by weight of a mixture of magnesium and zinc oxides having an average particle size of up to about 10 microns and which consists essentially of about 50 parts by weight of magnesium oxide, about 20 parts by weight of zinc oxide, from about 1 to 5 parts by weight of an oil-soluble or oil-dispersible surface active agent, 1 to 5 parts by weight of a micro-crystalline wax, and from 20 to 30 parts by weight of a mineral oil vehicle.

Claim 8

The process for curing haloprene polymers which comprises incorporating into the polymer stock, from about 0.2 to 12 parts by weight based on 100 parts by weight of the polymer, of a paste co-dispersion comprising from about 50% to about 80% by weight of a mixture of magnesium and zinc oxides having an average particle size of up to about 10 microns and which consists essentially of about 50 parts by weight of magnesium oxide, about 20 parts by weight of zinc oxide, from about 1 to 5 parts by weight of an oil-soluble or oil-dispersible surface active agent, 1 to 5 parts by weight of a micro-crystalline wax, and from 20 to 30 parts by weight of a mineral oil vehicle.

Claim 9

In the method of curing haloprene polymers wherein magnesium oxide and zinc oxide are utilized as curing additives the improvement which comprises a. providing a paste co-dispersion comprising from about 50% to about 80% by weight of a mixture of magnesium and zinc oxides having an average particle size of up to about 10 microns and consisting essentially of from about 30 to 80 parts by weight of magnesium oxide, from about 10 to 60 parts by weight of zinc oxide and from about 1 to 5 parts by weight of an oil-soluble or oil-dispersible surface active agent in about 15 to 30 parts by weight of a mineral oil vehicle; b. mixing said paste co-dispersion with the polymer stock at the beginning of the compounding cycle, and c. heat-curing the resulting mixture.

Claim 10

In the method of curing haloprene polymers wherein magnesium oxide and zinc oxide are utilized as curing additives the improvement which comprises a. providing a paste co-dispersion comprising from about 50% to about 80% by weight of a mixture of magnesium and zinc oxides having an average particle size of up to about 10 microns and consisting essentially of from about 30 to 80 parts by weight of magnesium oxide, from about 10 to 60 parts by weight of zinc oxide and from about 1 to 5 parts by weight of an oil-soluble or oil-dispersible surface active agent in about 15 to 30 parts by weight of a mineral oil vehicle; b. mixing said paste co-dispersion with the polymer stock at the beginning of the compounding cycle, and c. heat-curing the resulting mixture.

Claim 11

The method of claim 7 wherein from about 0.2 to about 12 parts by weight of the paste is utilized per 100 parts by weight of said polymer.

Claim 12

The method of claim 7 wherein the paste comprises about 50 parts by weight of magnesium oxide, about 20 parts by weight of zinc oxide, from about 1 to 5 parts by weight of a sorbitan fatty acid ester, from 1 to 5 parts of a wax, and from about 20 to 30 parts by weight of mineral oil.

Claim 13

The process of claim 7 wherein the surface active agent is a sorbitan fatty acid ester, a fatty acid ester, a polyoxyethylene sorbitol ester or a fatty acid ester of an alkylene glycol.

Claim 14

The method of claim 7 wherein the paste is mixed with the polymer before or during massing or banding of the polymer.

Claim 15

An uncured haloprene polymer which can be cured rapidly at ordinary vulcanizing temperatures and which contains from about 0.2 to about 12 parts by weight, based on 100 parts of the polymer, of a paste co-dispersion comprising from about 50% to about 80% by weight of a mixture of magnesium and zinc oxides having an average particle size of up to about 10 microns and consisting essentially of a mixture of from about 30 to 80 parts of magnesium oxide, 10 to 60 parts of zinc oxide, 1 to 5 parts by weight of an oil-soluble or oil-dispersible surface active agent, and from about 20 to 30 parts by weight of mineral oil.

Claim 16

An uncured haloprene polymer which can be cured rapidly at ordinary vulcanizing temperatures and which contains from about 0.2 to about 12 parts by weight, based on 100 parts of the polymer, of a paste co-dispersion comprising from about 50% to about 80% by weight of a mixture of magnesium and zinc oxides having an average particle size of up to about 10 microns and consisting essentially of a mixture of from about 30 to 80 parts of magnesium oxide, 10 to 60 parts of zinc oxide, 1 to 5 parts by weight of an oil-soluble or oil-dispersible surface active agent, and from about 20 to 30 parts by weight of mineral oil.

Claim 17

The uncured polymer of claim 12 wherein the surface active agent is a sorbitan fatty acid ester.

Claim 18

The uncured haloprene polymer of claim 12 wherein the paste also contains from about 2 to 5 parts by weight of a modifying agent of the class consisting of waxes, metallic soaps, and clay.

Claim 19

The uncured polymer of claim 12 wherein the paste co-dispersion also contains up to about 5 parts of an organic curing accelerator.

Claim 20

An uncured haloprene polymer which can be cured rapidly at ordinary vulcanizing temperatures and which contains from about 0.2 to about 12 parts by weight, based on 100 parts of the polymer, of a paste co-dispersion comprising from about 50% to about 80% by weight of a mixture of magnesium and zinc oxides having an average particle size of up to about 10 microns and consisting essentially of a mixture of about 50 parts of magnesium oxide, about 20 parts of zinc oxide, and about 1 to 5 parts of a sorbitan fatty acid ester in about 20 to 30 parts of a mineral oil.

Claim 21

An uncured haloprene polymer which can be cured rapidly at ordinary vulcanizing temperatures and which contains from about 0.2 to about 12 parts by weight, based on 100 parts of the polymer, of a paste co-dispersion comprising from about 50% to about 80% by weight of a mixture of magnesium and zinc oxides having an average particle size of up to about 10 microns and consisting essentially of a mixture of about 50 parts of magnesium oxide, about 20 parts of zinc oxide, and about 1 to 5 parts of a sorbitan fatty acid ester in about 20 to 30 parts of a mineral oil.

Claim 22

The uncured haloprene polymer of claim 16 containing about 4 to 6 parts of the paste per hundred parts of polymer.

Claim 23

The uncured haloprene polymer of claim 16 wherein the sorbitan fatty acid ester in the paste is sorbitan mono-oleate.

Claim 24

The uncured haloprene polymer of claim 16 wherein the paste dispersion also contains about 1 to 2 parts of a micro-crystalline wax.

Claim 25

The uncureD haloprene polymer of claim 19 wherein the paste dispersion also contains about 1 to 2 parts of an organic curing accelerator.

Claim 26

The uncured haloprene polymer of claim 20 wherein the organic accelerator is a cyclic thiourea.