Colloidal dispersions of ammonia-comminuted particles of methyl methacrylate-acid copolymers

Abstract

Abstract AQUEOUS COLLOIDAL DISPERSIONS OF SOLID PARTICLES OF AN INTERPOLYMER IN WHICH AT LEAST 95 PERCENT BY NUMBER OF SAID PARTICLES HAVE DIAMETERS OF 0.1 TO 0.01 MICRON, AND SAID INTERPOLYMER HAS A WEIGHT AVERAGE MOLECULAR WEIGHT OF AT LEAST 10,000 AND CONSISTS ESSENTIALLY OF 20-99 PERCENT BY WEIGHT OF METHYL METHACRYLATE, 0-75, PERCENT BY WEIGHT OF ESTER SELECTED ROM THE GROUP CONSISTING OF ALKYL ACRYLATES HAVING 4 TO 16 CARBON ATOMS AND ALKYL METHACRYLATES HAVING FROM 6 TO 16 CARBON ATOMS, 0-40 PERCENT BY WEIGHT OF ETHYLENICALLY UNSATURATED COPOLYMERIZABLE MONOMER SELECTED FROM THE GROUP CONSISTING OF STYRENE, VINYL ACETATE, VINYL FLUORIDE, VINYL CHLORIDE, VINYLIDENE FLUORIDE AND VINYLIDENE CHLORIDE, AND ACID SELECTED FROM THE GROUP CONSISTING OF 1-8 PERCENT BY WEIGHT OF ACRYLIC ACID, 108 PERCENT BY WEIGHT OF METHACRYLIC ACID, 4-8 PERCENT BY WEIGHT OF MALEIC ACID, AND 4-8 PERCENT BY WEIGHT OF ITACONIC ACID. THESE DISPERSIONS ARE PREPARED BY ADDING TO A MIXTURE OF WATER AND SOLID PARTICLES OF SAID INTERPOLYMER (A) 30-150 PERCENT OF THE STOICHIOMETRIC AMOUNT OF AMMONIUM HYDROXIDE REQUIRED TO NEUTRALIZE THE ACID PRESENT IN SAID INTERPOLYMER AND (B) WHEN THE SECOND ORDER TRANSITION TEMPERATURE OF THE INTERPOLYMER IS ABOVE 35*C., AN AMOUNT OF UP TO 1 PART PER PART BY WEIGHT OF SAID INTERPOLYMER, EFFECTIVE TO RENDER SAID INTERPOLYMER COLLOIDALLY DISPERSIBLE, OF A LIQUID ORGANIC COMMINUTION AGENT WHICH IS CAPABLE OF AT LEAST SWELLING THE INTERPOLYMER PARTICLES AND IS INERT TOWARD THE AMMONIUM HYDROXIDE, AND VIGOROUSLY AGITATING THE RESULTING MIXTURE AT A TEMPERATURE OF 40-100*C. UNTIL A REDUCTION IN THE SIZE OF THE INTERPOLYMER PARTICLES TAKES PLACE SUCH THAT AT LEAST 95 PERCENT BY NUMBER OF SAID PARTICLES HAVE DIAMETERS OF LESS THAN 0.1 MICRON.

Inventors

• 👤 K Winkelblech

Bibliographic Details