| Abstract: | A systematic study on the synthesis, characterization, degradation, and drug release of fatty acid terminated poly(sebacic acid) (PSA) is reported. Fatty acid terminated sebacic acid polymers were synthesized by melt condensation of acetate anhydrides of linear fatty acids (C8–C18) and sebacic anhydride oligomers to yield waxy off-white materials. Polymers with molecular weights (Mw) in the range of 9,000 and 5,000 were obtained for the 10% and 30% (weight ratio) containing fatty terminals, respectively. Up to about 30% of fatty acid terminals, the final product is mainly fatty terminated polymer with up to about 5% w/w of the symmetric fatty anhydride. Increasing amounts of fatty acid acetate anhydride in the polymerization mixture had little effect on the polymer molecular weight up to a ratio of 40 : 60 (fatty acid acetate : sebacic acid oligomer) which remains in the range of 5,000–8,000. Above this ratio the molecular weight dropped to a level of 2,000–3,000 and the percent of the symmetric anhydride increased to 10–40%. The fatty terminals had little effect on PSA melting point and crystallinity. However, the fatty terminals had a significant effect on the polymer degradation and drug release rate. PSA with 30% w/w of C14–C18 terminals degraded and released the incorporated drug for more than 4 weeks as compared with 10 days for the acetate-terminated PSA. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 3337–3344, 1999 |
