• Fibers and Polymers
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• 제6권1호
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• pp.13-18
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• 2005

PLA/LPCL/HPCL blend fibers composed of poly (lactic acid) (PLA), low molecular weight poly ($\varepsilon$-caprolactone) (LPCL), and high molecular weight poly ($\varepsilon$-caprolactone) (HPCL) were prepared by melt blending and spinning for bioab­sorbable filament sutures. The effects of blending time and blend composition on the X-ray diffraction patterns and tensile properties of PLA/LPCL/HPCL blend fibers were characterized by WAXD and UTM. In addition, the effect of in vitro degra­dation on the weight loss and tensile properties of the blend fibers hydrolyzed during immersion in a phosphate buffer solu­tion at pH 7.4 and 37$^{\circ}C$ for 1-8 weeks was investigated. The peak intensities of PLA/LPCL/HPCL blend fibers in X-ray diffraction patterns decreased with an increase of blending time and LPCL contents in the blend fibers. The weight loss of PLA/LPCL/HPCL blend fibers increased with an increase of blending time, LPCL contents, and hydrolysis time while the tensile strength and modulus of the blend fibers decreased. The tensile strength and modulus of the blend fibers were also found to be increased with an increase of HPCL contents in the blend fibers. The optimum conditions to prepare PLA/LPCL/HPCL blend fibers for bioabsorbable sutures are LPCL contents of $5 wt\%, HPCL contents of $35 wt\%, and blending time of 30 min. The strength retention of the PLA/LPCL/HPCL blend fiber prepared under optimum conditions was about $93.5\% even at hydrolysis time of 2 weeks.

• 폴리머
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• 제29권3호
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• pp.314-319
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• 2005

촉매인 stannous octeate 존재 하에서 글리콜리드를 이관능성 개시제인 1,4-butanediol, 1,6-hexanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol과 반응시켜 4가지 종류의 새로운 지방족 디올을 합성하였다. 이들 새로운 디올과 succinic acid, adipic acid, 혹은 suberic acid와 titanium(IV) isopropoxide 촉매하에서 170, 190, 또는 $220^{circ}C$에서 축합중합 시켜 분자구조가 규칙적으로 배열된 새로운 지방족 폴리에스테르와 무질서한 구조를 갖는 폴리에스테르를 각각 얻었다. 이들 지방족 폴리에스테르들의 유리전이온도($T_g$)는 -40에서 $30^{circ}C$ 사이였다. 또한 $170^{circ}C$에서 제조된 분자구조가 규칙적으로 배열된 폴리에스테르가 높은 온도에서 합성된 구조가 무질서한 폴리에스테르들보다 $T_g$가 $5-10^{circ}C$ 정도 높았다. 체외분해 실험 결과, 분자구조가 규칙적으로 배열된 폴리에스테르가 불규칙한 중합체보다 완충용액 속에서 가수분해속도가 느렸다.