Early stage structural evolution of PLLA porous scaffolds in thermally induced phase separation process and the corresponding biodegradability and biological property
Early stage structural evolution of PLLA porous scaffolds in thermally induced phase separation process and the corresponding biodegradability and biological property
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PLLA多孔支架在热诱导相分离过程中的早期结构演化及其相应的生物降解性和生物性能
DOI：
10.1016/j.polymdegradstab.2012.03.014
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发表时间：
2012-06-01
影响因子：
5.9
通讯作者：
Du, Chang
中科院分区：
文献类型：
--
作者：
Shao, Jundong;Chen, Cong;Du, Chang
研究了热诱导相分离过程中PLLA多孔支架的结构演变及其可生物降解性和生物学性能。采用扫描电镜（SEM）、WAXD、XPS、接触角测量、原子力显微镜（AFM）、水解降解和细胞培养实验等方法研究了其形貌、结晶行为、化学结构、表面性能、疏水性、生物降解性和生物学性能。最初的相分离导致非晶凝胶与非晶沉淀斑块的凝结，其次是PLLA晶体的成核。随着胶凝过程的延长，形成微孔结构。在淬火初期，观察到温度相关的相行为。随着结晶度的增加，聚合物的结构随着胶凝时间的延长而向更有序、致密的状态转变。XPS分析证实了甲基的表面偏析可能对水接触角的增加有一定的影响。在猝灭初期，聚合物的结构、结晶度、化学结构、表面性能和聚合物链的排列方式等的演变对其疏水性、生物降解性和生物性能有直接的功能影响。(C) 2012 Elsevier Ltd.版权所有。
The structural evolution and the corresponding biodegradability and biological property of PLLA porous scaffolds during the early quenching period in a thermally induced phase separation process have been investigated. The morphology, crystallization behavior, chemical structure, surface property, hydrophobicity, biodegradability and biological property were studied by using SEM, WAXD, XPS, contact angle measurement, AFM, hydrolytic degradation and cell culture experiments. The initial phase separation resulted in an amorphous gel with the condensation of patches of amorphous precipitates, followed by the nucleation of PLLA crystals. With extending the gelation process, a microporous structure was formed. A temperature dependent phase behavior during the early quenching period has been observed. Along with the increase in the degree of crystallinity, structural transformation of the polymer toward a more ordered and compact state proceeded with the extending of the gelation time. The possible surface segregation of the methyl groups was confirmed by XPS analysis which may have certain effect on the increase of water contact angle. The evolution of architecture, crystallinity, chemical structure, surface property and the polymer chain packing mode, etc, during the early quenching period, has a direct functional consequence in the hydrophobicity, biodegradability as well as biological property. (C) 2012 Elsevier Ltd. All rights reserved.