## Abstract The hydrolytic degradation of three aromatic poly(esterโanyhdride)s, PEA's, was studied at 25ยฐC in buffer solutions at pH 6 and pH 7 over a period of 16 and 14 months, respectively. Two PEA's (1 and 2a) possessed an ester/anhydride mole ratio of 75 : 25. The loss of weight, the film thi
Processing and hydrolytic degradation of aromatic, ortho-substituted polyanhydrides
โ Scribed by Christi Bedell; Meng Deng; Theodore J. Anastasiou; Kathryn E. Uhrich
- Publisher
- John Wiley and Sons
- Year
- 2001
- Tongue
- English
- Weight
- 247 KB
- Volume
- 80
- Category
- Article
- ISSN
- 0021-8995
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โฆ Synopsis
Polyanhydrides containing 1,3-bis(p-carboxyphenoxy)propane, abbreviated poly(p-CPP), are currently being used as controlled-release devices for the treatment of brain cancer. These polymers are biodegradable and biocompatible and release pharmaceuticals in a controlled fashion. However, polyanhydrides have an important drawback: The polymers themselves are highly insoluble in both organic solvents and water and have high melting temperatures, rendering them difficult to process into fibers and/or films. Previously, we synthesized polymers that overcame the solubility and, thus, processing problems associated with poly(p-CPP). In this report, we describe the mechanical properties and hydrolytic degradation characteristics of these newly developed polyanhydrides. After formation of films by either compression-molding or solventcasting, the polymer surfaces were examined by SEM. Mechanical studies were also performed on the compression-molded samples. Compression-molded samples were sterilized by โฅ-irradiation and then examined by GPC for changes in their polymer structure. Lastly, the polymers and the degradation media were evaluated by TGA, DSC, GPC, and HPLC to gain a better understanding of the degradation process.
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