abstract |
Condensation polymers of high molecular weight, such as polyesters, polyureas, and polyamides, are usually prepared at temperatures of 200 DEG C. or greater. However, by utilizing the catalyst system of the present invention condensation polymers can be synthesized at much lower temperatures. These catalyst systems are comprised of (1) a silicon-phosphorus composition which contains at least one divalent oxygen atom which is bonded directly to a tetravalent silicon atom and a trivalent or pentavalent phosphorus atom; and (2) at least one acid acceptor. For example, P(OSiR3)3 wherein R can be an aliphatic or aromatic hydrocarbon radical, can be used in conjunction with a basic solvent as a catalyst system. Polymeric agents having pendant diphenylphosphine dichloride groups can also be used in conjunction with an acid acceptor as a catalyst system. |