PURPOSE: To efficiently obtain the subject polymer, excellent in weather and heat resistance, water repellency and low surface tension and refractivity and useful as a surface treading agent, etc., by polymerizing a cationic polymerizable monomer in the presence a protonic acid, etc., using a specific cationic polymerization initiator.
CONSTITUTION: A cationic polymerizable monomer such as ethyl vinyl ether is polymerized in the presence of a protonic acid such as phosphoric acid and/or a Broensted acid using a fluoroalkyl group-containing derivative of formula I [Rf is (C2)nX (X is F, Cl or H; n is 1-10) or formula II (n is 0-8); R14 is 1-20C alkoxy, 3-8C cycloalkyl, naphthyl, etc.; R15 is H, 1-5C alkyl or alkoxy] as a cationic polymerization initiator to afford the objective polymer having 500-1000000 average molecular weight.
KAWAMOTO KEIJI
ISHIDOYA MASAHIRO
