| abstract |
Copolymerisation is carried out in the presence of a radical polymerisation initiator, of an aqueous mixture of, by weight:n (a) 60 - 99.8% of an acrylic acid fluoroalkyl ester derivative up to 90% of which may be replaced by an acrylic acid alkyl ester and up to 99% of which may be replaced by a radical polymerisable vinyl monomer; (b) 0.1 - 20% of an acrylic acid derivative, (c) 0.1 - 20% of a polyfunctional monomer causing internal cross-linking of the copolymer and (d) optionally 0.001 - 10% of a vinyl monomer having a sulfonic acid group. n The resultant emulsion contains copolymer particles of size 0.03 to 2 µm and a specific gravity of 0.9 to 1.5, and it has excellent stability and can be dispersed in a buffer solution or physiological saline solution. |