| abstract |
Cationically polymerisable styryloxy resins having urethane linkages, represented by the formula IIIn wherein R¹ and R² are H, or one of R¹ and R² is H and the other is methyl; nR³ and R⁴ (which may be the same or different) are H, lower alkyl, or alkoxy if R² is not methyl; nR⁵ is a divalent hydrocarbon radical; nG¹ is an n-valent hydrocarbon radical free of amino, aliphatic thiol, aliphatic hydroxyl or other groups which interfere with cationic polymerisation; nand n is an integer of 2 or more. n G¹ is a hydrocarbon backbone which is not interrupted by a hetero atom. Preferably G¹ is a residue of a diene homopolymer or copolymer, in which case the resins produce flexible polymers. The resins are polymerised with a cationic polymerisation initiator or latent acid catalyst. The resins have utility in the field of electronics. |