Process for preparing fluid sols of organic elastomers

Claim 1

A METHOD FOR PREPARING A FLUID SOL OF A HIGH-MOLECULAR-WEIGHT RUBBEROID POLYMER SELECTED FROM THE CLASS CONSISTING OF POLYISOBUTYLENE, NATURAL RUBBER, BUTADIENESTYRENE COPOLYMERS, BUTADIENE-METHYL METHACRYLATE COPOLYMERS, POLYCHLOROPRENE, BUTADIENE-ACRYLONITRILE COPOLYMERS, POLYETHYLENE POLYSULFIDE, POLYPROPYLENE POLYSULFIDE, POLYVINYL CHLORIDE, AND ISOBUTYLENE-ISOPRENE COPOLYMERS, WHICH COMPRISES TREATING SAID POLYMER WITH A FIRST VOLATILE LIQUID WHICH, AT THE TREATING TEMPERATURE, IS NOT A SOLVENT FOR SAID POLYMER BUT IS A SWELLANT THEREFOR, THE TREATMENT BEING SUCH THAT THE POLYMER ABSORBS SUFFICIENT SWELLANT TO EFFECT A SUBSTANTIAL SWELLING THEREOF, SAID TREATING BEING EFFECTED AT A TEMPERATURE SUFFICIENTLY LOW TO AVOID THE FORMATION OF A PERCEPTIBLE GUMMY LAYER ON THE EXTERIOR SURFACES OF SAID POLYMER, THEREAFTER TREATING AND PROGRESSIVELY DISSOLVING THE SWOLLEN POLYMER IN A SOLVENT-SWELLANT MIXTURE COMPRISING (1) A SECOND VOLATILE LIQUID WHICH, AT THE TREATING TEMPERATURE, IS NOT A SOLVENT FOR SAID POLYMER BUT IS A SWELLANT THEREFOR AND (2) A THIRD LIQUID WHICH IS A SOLVENT FOR SAID POLYMER AT THE TREATING TEMPERATURE AND IS MISCIBLE WITH SAID SECOND LIQUID, SAID DISSOLVING BEING EFFECTED WHILE SIMULTANEOUSLY BOILING OFF SWELLANT FROM THE LIQUID MIXTURE AND FROM THE SWOLLEN POLYMER TO GRADUALLY REDUCE THE SWELLANT CONCENTRATION IN THE LIQUID MIXTURE AND CAUSE MECHANICAL DISRUPTION OF UNDISSOLVED POLYMER BY THE VAPORIZATION AND ESCAPE OF SWELLANT BUBBLES FROM SAID UNDISSOLVED POLYMER, SAID FIRST AND SECOND LIQUIDS BEING LOWER BOILING THAN SAID THIRD LIQUID.

Claim 2

A METHOD FOR PREPARING A FLUID SOL OF A HIGH-MOLECULAR-WEIGHT RUBBEROID POLYMER SELECTED FROM THE CLASS CONSISTING OF POLYISOBUTYLENE, NATURAL RUBBER, BUTADIENESTYRENE COPOLYMERS, BUTADIENE-METHYL METHACRYLATE COPOLYMERS, POLYCHLOROPRENE, BUTADIENE-ACRYLONITRILE COPOLYMERS, POLYETHYLENE POLYSULFIDE, POLYPROPYLENE POLYSULFIDE, POLYVINYL CHLORIDE, AND ISOBUTYLENE-ISOPRENE COPOLYMERS, WHICH COMPRISES TREATING SAID POLYMER WITH A FIRST VOLATILE LIQUID WHICH, AT THE TREATING TEMPERATURE, IS NOT A SOLVENT FOR SAID POLYMER BUT IS A SWELLANT THEREFOR, THE TREATMENT BEING SUCH THAT THE POLYMER ABSORBS SUFFICIENT SWELLANT TO EFFECT A SUBSTANTIAL SWELLING THEREOF, SAID TREATING BEING EFFECTED AT A TEMPERATURE SUFFICIENTLY LOW TO AVOID THE FORMATION OF A PERCEPTIBLE GUMMY LAYER ON THE EXTERIOR SURFACES OF SAID POLYMER, THEREAFTER TREATING AND PROGRESSIVELY DISSOLVING THE SWOLLEN POLYMER IN A SOLVENT-SWELLANT MIXTURE COMPRISING (1) A SECOND VOLATILE LIQUID WHICH, AT THE TREATING TEMPERATURE, IS NOT A SOLVENT FOR SAID POLYMER BUT IS A SWELLANT THEREFOR AND (2) A THIRD LIQUID WHICH IS A SOLVENT FOR SAID POLYMER AT THE TREATING TEMPERATURE AND IS MISCIBLE WITH SAID SECOND LIQUID, SAID DISSOLVING BEING EFFECTED WHILE SIMULTANEOUSLY BOILING OFF SWELLANT FROM THE LIQUID MIXTURE AND FROM THE SWOLLEN POLYMER TO GRADUALLY REDUCE THE SWELLANT CONCENTRATION IN THE LIQUID MIXTURE AND CAUSE MECHANICAL DISRUPTION OF UNDISSOLVED POLYMER BY THE VAPORIZATION AND ESCAPE OF SWELLANT BUBBLES FROM SAID UNDISSOLVED POLYMER, SAID FIRST AND SECOND LIQUIDS BEING LOWER BOILING THAN SAID THIRD LIQUID.