Effect of Stereochemistry on Physical Behavior and Degradation in Polylactide Systems

• Main Authors: Luh Jing-Win, 陸敬文
• Other Authors: David S.-G.Hu
• Format: Others
• Language: zh-TW
• Published: 1994
• Online Access: http://ndltd.ncl.edu.tw/handle/19753288874317334365

碩士 === 國立臺灣科技大學 === 纖維工程技術系 === 82 === The objective for part one is to investigate the time-dependent, structural relaxation and formation of precipitates of PDLLA/PLLA ( weight ratio PDLLA:PLLA=1: 1 ).The thermal behavior of polymers were analyzed with differential scanning calorimetry ( DSC ).DMA was used to measure the change in modulus at transition temperature.The vibration of functional groups of polymers were analyzed with FT-IR.The wide-angle X-ray scattering ( WAXS ) and solid-state 13C-NMR were used to analyze the crystalline morphology and comformation of polymers. This research is specifically concerned with hydrolysis behavior of biodegradable polymers, namely, semi-crystalline poly(L-lactide) (PLLA), amorphous poly ( D,L-lactide ) ( PDLLA ) and semi- crystalline poly ( ε -caprolactone)(PCL), under the various times of hydrolysis and temperatures. The vibration of functional groups of polymers after hydrolysis were analyzed with FT-IR.GPC and DSC were used to measure the variation of molecular weight and degree of crystalline with hydrolysis time.The chain degradation process can be described by first-order auto-catalytic kinetics.Futhermore, activation energy of hydrolysis can be obtained by Arrhenius equation.