Synthesis and Enzymatic Degradation of Aliphatic Polyesters Copolymerized with Trimesic Acid
| Autor: | Taizou Hasegawa, Minoru Nagata, Tsuyoshi Kiyotsukuri, Naoto Tsutsumi, Wataru Sakai |
|---|---|
| Rok vydání: | 1997 |
| Předmět: | |
| Zdroj: | Journal of Macromolecular Science, Part A. 34:965-973 |
| ISSN: | 1520-5738 1060-1325 |
| DOI: | 10.1080/10601329708015004 |
| Popis: | Network copolyesters were made from adipic acid and ethylene glycol with 10–40 mol% trimesic acid (Y). Prepolymers prepared by melt polycondensation were cast from dimethylformamide solution and postpolymerized at 260°C for various times to form a network. The degree of reaction (D R), estimated from the infrared absorbance of hydroxyl and methylene groups, increased with increasing postpolymerization time and leveled out at about 90% after 4–6 hours. Heat distortion temperatures (T h) measured by thermomechanical analysis increased greatly from −83 to 48°C upon the incorporation of Y. Wide-angle x-ray diffraction patterns showed that the copolymer films are amorphous. Density, tensile strength, and Young's modulus decreased for the copolymers with 10–30 mol% Y, whereas they increased drastically for the copolymer with 40 mol% Y. The enzymatic degradation was estimated by the weight loss of the copolymer films in buffer solutions with a lipase at 37°C. The weight loss decreased remarkably with in... |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|