Emulsion polymerization in the presence of lignosulfonate salt

Claim 2

An improved emulsion polymerization process for preparing a polymer latex comprising polymerizing an emulsion polymerizable ethylenically unsaturated monomeric material in an aqueous medium in the presence of an emulsion polymerization catalyst for said monomeric material, and in the presence of an anionic principal emulsifying agent, the improvement comprising including a water-soluble lignosulfonate salt as an emulsion modifier.

Claim 3

The process of claim 1, wherein said lignosulfonate salt is present in an amount of from 0.1 to 6 parts, and said principal emulsifier is present in an amount of from 0.1 to 3 parts, per 100 parts by weight of the said monomeric material, the resulting latex having an average particle size of from 500 to 5,000 Angstroms.

Claim 4

The process of claim 1, wherein the emulsion polymerization is conducted at a temperature of from 5° to 80° C.

Claim 5

The process of claim 1, wherein said monomeric material includes a monomer having carboxylic funtionality.

Claim 6

The process of claim 4, wherein the emulsion polymerization is conducted at a pH of from 2 to 6.

Claim 7

An emulsion polymerization process for preparing a rubber latex comprising agitating, at a temperature of from 5° to 80° C, a mixture of water and monomeric material selected from conjugated dienes with or without at least one copolymerizable monoethylenically unsaturated monomer, in the presence of an emulsion polymerization catalyst for said monomeric material in an amount effective to catalyze the polymerization of said monomeric material, and in the presence of from 0.1 to 6 parts, per 100 parts by weight of said monomeric material, of a water-soluble lignosulfonate salt as an emulsion modifier, and from 0.1 to 3 parts, per 100 parts by weight of said monomeric material, of a different anionic principal emulsifying agent, resulting in a stable rubber latex having a particle size of from 500 to 5,000 Angstroms average diameter as determined by turbidity measurement.

Claim 8

An emulsion polymerization process for preparing a rubber latex comprising agitating, at a temperature of from 5° to 80° C, a mixture of water and monomeric material selected from conjugated dienes with or without at least one copolymerizable monoethylenically unsaturated monomer, in the presence of an emulsion polymerization catalyst for said monomeric material in an amount effective to catalyze the polymerization of said monomeric material, and in the presence of from 0.1 to 6 parts, per 100 parts by weight of said monomeric material, of a water-soluble lignosulfonate salt as an emulsion modifier, and from 0.1 to 3 parts, per 100 parts by weight of said monomeric material, of a different anionic principal emulsifying agent, resulting in a stable rubber latex having a particle size of from 500 to 5,000 Angstroms average diameter as determined by turbidity measurement.

Claim 9

The process of claim 6, wherein said monomeric material comprises a mixture of a conjugated diene, a copolymerizable vinyl aryl monomer and a copolymerizable ethylenically unsaturated carboxylic acid, the pH of the polymerization mixture during the said process being from 2 to 6.

Claim 10

The process of claim 7, wherein said conjugated diene is butadiene, said vinyl aryl monomer is styrene, and said carboxylic acid is itaconic acid.

Claim 11

The process of claim 6, wherein said lignosulfonate salt is an alkali metal or alkaline earth metal lignosulfonate.

Claim 12

The process of claim 6, wherein said anionic principal emulsifying agent is sodium dodecylbenzenesulfonate.

Claim 13

The process of claim 6, wherein said anionic principal emulsifying agent is an alpha-olefinsulfonate.

Claim 14

The process of claim 6, wherein said anionic principal emulsifying agent is sodium laurylsulfate.

Claim 15

The process of claim 6, wherein said anionic principal emulsifying agent is sodium dicyclohexylsulfosuccinate.

Claim 16

The process of claim 6, wherein said lignosulfonate salt is sodium lignosulfonate.

Claim 17

The process of claim 6, wherein said lignosulfonate salt is calcium lignosulfonate.

Claim 18

An emulsion polymerization process for preparing a rubber latex comprising agitating, at a temperature of from 5° to 80° C, a mixture of water and monomeric material comprising a conjugated diene, a copolymerizable vinyl aryl monomer and a copolymerizable monoethylenically unsaturated carboxylic acid, at a pH of 2 to 3.5, in the presence of an emulsion polymerization catalyst for said monomeric material in an amount effective to catalyze the polymerization of said monomeric material, and in the presence of from 0.2 to 5 parts, per 100 parts by weight of said monomeric material, of a water-soluble lignosulfonate alkali metal or alkaline earth metal salt as an emulsion polymerization modifier and from 0.5 to 1.5 parts, per 100 parts by weight of said monomers, of a different anionic principal emulsifying agent, resulting in a stable rubber latex having a particle size of from 1,000 to 3,000 Angstroms average diameter as determined by turbidity measurement.

Claim 19

An emulsion polymerization process for preparing a rubber latex comprising agitating, at a temperature of from 5° to 80° C, a mixture of water and monomeric material comprising a conjugated diene, a copolymerizable vinyl aryl monomer and a copolymerizable monoethylenically unsaturated carboxylic acid, at a pH of 2 to 3.5, in the presence of an emulsion polymerization catalyst for said monomeric material in an amount effective to catalyze the polymerization of said monomeric material, and in the presence of from 0.2 to 5 parts, per 100 parts by weight of said monomeric material, of a water-soluble lignosulfonate alkali metal or alkaline earth metal salt as an emulsion polymerization modifier and from 0.5 to 1.5 parts, per 100 parts by weight of said monomers, of a different anionic principal emulsifying agent, resulting in a stable rubber latex having a particle size of from 1,000 to 3,000 Angstroms average diameter as determined by turbidity measurement.

Claim 20

The process of claim 16, wherein said carboxylic acid is itaconic acid.

Claim 21

The process of claim 16, wherein said monomeric material is a mixture of butadiene, styrene, and itaconic acid.

Claim 22

The process of claim 16, wherein said anionic principal emulsifying agent is sodium dodecylbenzenesulfonate.

Claim 23

A stable large particle size latex resulting from the process of claim 1.