Abstract: A purification process for monomers and solvents used in the production of polymers by solution polymerization comprises supplying impure monomer and solvent to a distillation column which rejects light and heavy impurities from the top and bottom respectively and which dries the monomer-solvent mixture by azeotropic distillation, and withdrawing a pure monomer solvent vapor as a side stream from a point intermediate the top and bottom of the column.
Type:
Grant
Filed:
January 26, 1981
Date of Patent:
July 13, 1982
Assignee:
The International Synthetic Rubber Company, Limited
Abstract: The invention relates to a continuous flow process for the preparation of graft copolymers, for example ABS, wherein a mixture of a polybutadiene and/or styrenebutadiene copolymer latex, one or more vinyl aromatic monomers and one or more unsaturated nitrile monomers is continuously supplied to a first stage, graft polymerization is initiated in said first stage, the mixture is continuously removed from the said first stage and supplied to at least a second stage wherein graft polymerization is continued, the temperature in each stage being 50.degree. to 100.degree. C, the conversion of monomers to polymer in the first stage not exceeding 65% by weight, and the overall conversion being at least 80% by weight.
Type:
Grant
Filed:
February 12, 1976
Date of Patent:
July 5, 1977
Assignee:
The International Synthetic Rubber Company, Limited
Abstract: The invention relates to a soil stabilization composition comprising a rubber latex of solids content at least 40% by weight and a compatible oil which is prepared by admixing the oil and the latex in the presence of additional emulsifier and in the substantial absence of added water. The composition may be applied as such and optionally rotovated into the soil after application. If desired, a bitumen emulsion may be included in the composition.
Type:
Grant
Filed:
June 7, 1976
Date of Patent:
June 14, 1977
Assignee:
The International Synthetic Rubber Company, Limited
Abstract: Carboxylated latices are prepared continuously under substantially constant temperature conditions in a total reaction time of 6 to 10 hours using two or more reactors at controlled temperatures. The monomers and the reaction ingredients which are specified are all supplied to the first reactor and no additions are made to the subsequent reactors. The process uses an alkali metal or ammonium alkyl aryl sulphonate emulsifier, an alkali metal or ammonium electrolyte and a source of peroxydisulphate ion. The carboxylated latices obtained are particularly useful for carpet backing and paper coating applications.
Type:
Grant
Filed:
July 31, 1974
Date of Patent:
June 29, 1976
Assignee:
The International Synthetic Rubber Company, Limited
Inventors:
Alan Arthur John Feast, Charles Mack Scott