Thickener prepn. by monomer mixt. copolymerisation in organic solvent - contg. ethylene!-propylene! non-conjugated diene! copolymer elastomer as protective colloid

摘要

Thickeners are prepd. by copolymerising monomer mixts. contg., by wt., (a) 20-70% (meth)acrylic acid and/or maleic-, fumaric- and/or itaconic acid mono-esters, (b) 30-80% (meth)acrylates and/or vinyl esters of 2-4C monocarboxylic acids, (c) 0-10% (meth)accrylonitrile and/or (meth)acrylamide, (d) 0-30% opt. substd. styrene and (e) 0-2% of =1 monomer contg. =2 ethylenically unsatd. double bonds, in an inert solvent, by pptn. polymerisation, using polymerisation initiators. Polymerisation is at 100-150(105-125) degrees C in the presence of 2-10wt.%, w.r.t. monomers, of a C2H4-C3H6 elastomer contg. 10wt.% inter-polymerised no(-conjugated diene. The elastomer has I2-index 1-15 and Mooney viscosity (100 degrees C, ML 1+4), 30-55. The thickeners can be used inthe prepn. of printing pastes, paper coating mixts. and aq. coating compsns. Elastomer presence prevents formation of highly crosslinked copolymers which do not dissolve in aq. alkali solns. In polymerisation, the elastomers act as protective colloids and are built into the copolymer.