Patent ID: 6524606
Filing Date: 2003-02-25
Classification: C08G,Y10S

Abstract:
A polyorthoester of formula I or formula II: where:R* is a C1-4 alkyl; R is a bond, â€”(CH2)aâ€”, or â€”(CH2)bâ€”Oâ€”(CH2)câ€”; where a is an integer of 1 to 10, and b and c are independently integers of 1 to 5; n is an integer of at least 5; and A is a mixture of R1 and R4, and optionally R2 and or R3, where R1 is: where:p is an integer of 1 to 20; R5 is hydrogen or C1-4 alkyl; and R6 is: where:s is an integer of 0 to 30; t is an integer of 2 to 200; and R7is hydrogen or C1-4 alkyl; R2 is: â€ƒR3 is: where:x is an integer of 0 to 30; y is an integer of 2 to 200; R8 is hydrogen or C1-4 alkyl; R9 and R10 are independently C1-12 alkylene; R11 is hydrogen or C1-6 alkyl and R12 is C1-6 alkyl; or R11 and R12 together are C3-10 alkylene; and R4 is the residual of a diol containing at least one amine functionality incorporated therein; in which at least 0.1 mol % of the A units are R1, and at least 0.1 mol % of the A units are R4.