| abstract |
Under particular conditions, a cationic ring-opening polymerization of a first oxirane monomer selected from the group consisting of an acyclic glycidyl ether, a cyclic glycidyl ether, and a haloalkyl epoxide, in the presence of a hydroxyl-containing organic material ("HCM"), for example a polymer (referred to herein as a 'hydroxyl-prepolymer'), and a particular catalyst, produces a polymerization having 'living polymerization' characteristics. The result is that molecular weight (mol wt) of the resulting polymer is directly proportional to the conversion of the monomer to said resulting polymer. This HCM serves as a chain propagator which initially furnishes OH groups as propagation sites. Subsequently, a second oxirane monomer, different from said first, is sequentially polymerized to yield a block copolymer. Branched block copolymers, or linear block copolymers of a HCM and (a) one or more glycidyl ethers, or (b) a haloalkyl epoxide and at least one glycidyl ether, may be prepared. Halogen containing segments of the block copolymers of the invention may be aminated to produce amphophilic polymers. |