Patent GB-598872-A (GB)
Title: Improvements in the creaming of synthetic rubber latices
IPC: C08C1/08
Filed: 1945-09-21
Abstract: A method of creaming an aqueous emulsion polymerisate of butadiene-1,3 hydrocarbons and copolymerisates of butadiene-1,3 hydrocarbons with other polymerisable compounds comprises creaming the aqueous emulsion polymerisate in the presence of a hydrophilic colloidal creaming agent and 0.4 to 3 per cent by weight, based on the water phase of the polymerisate, of strong alkali from the group consisting of alkali-metal hydroxides such as potassium hydroxide and quaternary ammonium hydroxides such as trimethyl benzylammonium hydroxide.  The polyer may be polymerized butadiene-1,3; methyl-2-butadiene-1,3; pentadiene-1,3; or 2,3-dimethylbutadiene-1,3. The copolymer may be the product obtained by copolymerising one of the above compounds with other polymerisable substances, preferably those having the CH2=C< group such as styrene, vinyl naphthalene, a -methylene carboxylic acids and their esters, nitriles, and amides such as acrylic acid, methyl acrylate, methyl methacrylate, acrylonitrile, methacrylonitrile, methacrylamide, and also isobutylene.  The hydrophilic colloidal creaming agent may be a vegetable mucilage such as an alginate, pectate, or an extract obtained from plants belonging to the genera Cassia, Ceratonia, Caesalpinia, Poinciana, Astralagus, and Acacia, from the seaweed Chondrous Crispus, from the stem of the Cactus Opuntia monocantha, the leaves of Hibiscus rosa-sinensis, the pods of Hibiscus esculentus, the seeds of Tamarindus indica, tubers of Amorphallus, or corms of Crocus or Amaryllis.  Alternatively synthetic creaming agents such as polyacrylates, or alkylated celluloses or hemi-celluloses may be used.ALSO:A method of creaming an aqueous emulsion polymerisate of butadiene-1, 3, hydrocarbons and copolymerisates of butadiene-1, 3, hydrocarbons with other polymerisable compounds comprises creaming the aqueous emulsion polymerisate in the presence of a hydrophilic colloidal creaming agent and 0.4 to 3 per cent. by weight, based on the water phase of the polymerisate, of strong alkali from the group consisting of alkali-metal hydroxides such as potassium hydroxide and quaternary ammonium hydroxides such as trimethyl benzylammonium hydroxide.  The polymer may be polymerised butadiene-1, 3; methyl-2-butadiene-1, 3; pentadiene-1, 3; or 2, 3-dimethylbutadiene-1, 3.  The copolymer may be the product obtained by copolymerising one of the above compounds with other polymerisable substances, preferably those having the CH2=C= group such as styrene, vinyl naphthalene, a -methylene carboxylic acids and their esters, nitriles and amides, such as acrylic acid, methyl acrylate, methyl methacrylate, acrylonitrile, methacrylonitrile, methacrylamide, and also isobutylene.  The hydrophilic colloidal creaming agent may be a vegetable mucilage such as an alginate, pectate or an extract obtained from plants belonging to the genera Cassia, Ceratonia, Caesalpinia, Poinciana, Astralagus and Acacia, from the seaweed Chondrus Crispus, from the stem of the cactus opuntia monocantha, the leaves of Hibiscus rosa-sinensis, the pods of Hibiscus esculentus, the seeds of Tamarindus indica, tubers of Amorphallus or corms of crocus or Amaryllis.  Alternatively synthetic creaming agents such as polyacrylates, or alkylated celluloses or hemi-celluloses may be used.