摘要
研究了等通道转角挤压技术对生物降解材料聚(DL)-乳酸(PDLLA)的增强、增韧。探讨了挤压温度、挤压次数对PDLLA性能的影响。实验表明,随挤压次数增加,材料强韧性提高;挤压温度对材料性能影响明显。经过 2次挤压后,PDLLA的弯曲强度由83．3MPa增加到178．7 MPa;原始试样弯曲断口呈脆性断裂,强韧化挤压后,断口呈典型韧性断裂特征,强韧性明显提高。扫描电镜观察表明,断口有大量纤维尾端,呈明显纤维化。广角X射线衍射和差示扫描量热分析表明,随挤压次数增加,PDLLA玻璃化转变温度提高,结构更趋稳定。
The biodegradable material, poly （DL-lactic acid）（PDLLA）, was processed via equal channel angular extrusion （ECAE） and strengthening and toughening were observed. The mechanical strength of the PDLLA was increased with increasing extrusion times. After two times of ECAE, the bending strength of PDLLA increased from 83.3 MPa to 178.7 MPa. The bending fracture of PDLLA changed from brittle failure to ductile. Fibrillar structure on the longitudinal split surface and fibril ends on fracture surface were observed by SEM. Differential scanning calorimetry （DSC） and wide X-ray diffraction （XRD） indicated that the Tgof PDLLA increased and the dimension of crystal grain diminished after ECAE.
出处
《中国塑料》
CAS
CSCD
北大核心
2005年第11期58-62,共5页
China Plastics
基金
天津市高校科技发展基金资助(20030429)
关键词
强韧化
等通道转角挤压
聚(DL)-乳酸
toughness reinforcement
equal channel angular extrusion
poly （DL-lactic acid）
