Physico chemical and phase separation characterization of high molecular PLLA blended with low molecular PCL obtained from solvent cast processes
Physico chemical and phase separation characterization of high molecular PLLA blended with low molecular PCL obtained from solvent cast processes
复制标题
DOI：
10.1088/2053-1591/abb2c9
复制
发表时间：
2020-09-01
影响因子：
2.3
通讯作者：
Grabow, Niels
中科院分区：
文献类型：
--
作者：
Arbeiter, Daniela;Eickner, Thomas;Grabow, Niels
通过溶剂铸造生产的PLLA和PCL共混物通常表现出相分离和结晶行为，这对它们在某些生物医学应用（如可降解涂层或药物载体）的适用性有很大影响。因此，理解潜在的机制是很重要的。在本研究中，采用溶剂铸造法将高分子可生物降解半晶聚l -丙交酯（PLLA） （M-w = 320 kDa）与低分子可生物降解半晶聚e-己内酯（PCL） （M-w = 40 kDa）以不同的组合（10、50和90 wt.% PCL）混合。所得共混物分别在40℃、80℃和200℃下退火，并缓慢冷却以保持热力学平衡。采用扫描电镜、原子力显微镜、拉曼图像和差示扫描量热法研究了溶剂铸造PLLA/PCL共混物的结构、形貌和热性能。结果表明，溶剂铸造法制备的PLLA/PCL共混物的物理化学性能与熔融法制备的PLLA/PCL共混物有很大的不同。综上所述，共混物表现出复杂的相分离行为，这完全取决于制备方法和生产过程中温度的调节。
Blends of PLLA and PCL yielded by solvent casting usually exhibit phase separation and crystallization behavior which have a strong impact on their suitability for certain biomedical applications such as degradable coatings or drug carriers. Therefore, it is important to understand the underlying mechanisms. In this study, high-molecular biodegradable semi-crystalline poly(L-lactide) (PLLA) (M-w = 320 kDa) was blended with low-molecular biodegradable semi-crystalline poly(e-caprolactone) (PCL) (M-w = 40 kDa) in various combinations (10, 50 and 90 wt.% PCL) by solvent casting. The yielded blends were subjected to annealing at 40 degrees C, 80 degrees C and 200 degrees C and cooled down slowly to maintain thermodynamic equilibrium. Scanning electron microscopy, atomic force microscopy, Raman images and differential scanning calorimetry were used to investigate the structure, morphology and thermal properties of the solvent cast PLLA/PCL blends. It was shown that the physico-chemical properties of PLLA/PCL blends prepared by solvent casting differ substantially compared to those accessed by melt manufacturing processes. In summary, the blends showed a complex phase separation behavior, which is completely dependent on the method of preparation and the adjusted temperature during production process.