Effect of comonomer content on the crystallization kinetics and morphology of biodegradable poly(3-hydroxybutyrate-co-3-hydroxyhexanoate)
Effect of comonomer content on the crystallization kinetics and morphology of biodegradable poly(3-hydroxybutyrate-co-3-hydroxyhexanoate)
复制标题
共聚单体含量对可生物降解聚(3-羟基丁酸酯-co-3-羟基己酸酯)结晶动力学和形貌的影响
DOI：
10.1039/b907677h
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发表时间：
2009-01-01
影响因子：
3.3
通讯作者：
Qiu, Zhaobin
中科院分区：
文献类型：
--
作者：
Cai, Haoyuan;Qiu, Zhaobin
采用差示扫描量热法、偏光显微镜和广角x射线衍射研究了含有7、10和18 mol% 3-羟基己酸酯（HHx）共聚单体的可生物降解聚（3-羟基丁酸酯-co-3-羟基己酸酯）（PHBHHx）的结晶动力学和形貌。实验结果表明，PHBHHx共聚物的整体等温结晶速率随着结晶温度和HHx含量的升高而降低；然而，结晶机理保持不变。PHBHHx共聚物的平衡熔点温度随着HHx含量的增加而降低。在较宽的结晶温度范围内研究了PHBHHx的带状球晶形态和球晶生长速率。随着HHx共聚单体含量的增加，带间距和球晶生长速率均减小。所研究的PHBHHx共聚物均表现为II型到III型的结晶转变，并且随着HHx含量的增加结晶转变温度向低温范围转移。此外，增加HHx含量不会改变PHBHHx的晶体结构和晶胞参数，但会降低PHBHHx的结晶度。
Crystallization kinetics and morphology of biodegradable poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) containing 7, 10 and 18 mol% 3-hydroxyhexanoate (HHx) comonomer were investigated by differential scanning calorimetry, polarized optical microscopy and wide angle X-ray diffraction in detail in this work. The experimental results indicate that overall isothermal crystallization rates of PHBHHx copolymers are reduced with increasing crystallization temperature and HHx content; however, the crystallization mechanism remains unchanged. Moreover, the equilibrium melting point temperatures of PHBHHx copolymers decrease with increasing the HHx content. Banded spherulites morphology and spherulitic growth rates of PHBHHx have been studied in a wide crystallization temperature range. Both band spacing and spherulite growth rate decrease with increasing the HHx comonomer content. All the investigated PHBHHx copolymers exhibit a crystallization regime II to III transition, and the crystallization regime transition temperature shifts to low temperature range with increasing the HHx content. In addition, increasing the HHx content does not modify the crystal structure or crystal cell parameters but decreases the crystallinity of PHBHHx.