Saha Pathikrit, Khomlaem Chanin, Aloui Hajer, Kim Beom Soo
Department of Chemical Engineering, Chungbuk National University, Cheongju, Chungbuk 28644, Korea.
Polymers (Basel). 2021 Apr 24;13(9):1387. doi: 10.3390/polym13091387.
Biodegradable polyurethanes (PUs) were produced from castor oil (CO) and poly (3-hydroxybutyrate) diol (PHBD) using hexamethylene diisocyanate as a crosslinking agent. PHBDs of different molecular weights were synthesized through transesterification of bacterial PHB and ethylene glycol by changing the reaction time. The synthesized PHBDs were characterized in terms of Fourier transform infrared and proton nuclear magnetic resonance spectroscopy. A series of PUs at different NCO/OH and CO/PHBD ratios were prepared. The resulting CO/PHBD-based PUs were then characterized in terms of mechanical and thermal properties. Increasing PHBD content significantly increased the tensile strength of CO/PHBD-based PUs by 300% compared to neat CO-based PU. CO/PHBD-based PUs synthetized from short chain PHBD exhibited higher tensile strength compared to those produced from long chain PHBD. As revealed by scanning electron microscopy analysis, such improvement in stiffness of the resulting PUs is due to the good compatibility between CO and PHBD. Increasing PHBD content also increased the crystallinity of the resulting PUs. In addition, higher degradation rates were obtained for CO/PHBD-based PUs synthetized from long chain PHBD compared to neat CO PU and PUs produced from short chain PHBD.
以蓖麻油（CO）和聚（3-羟基丁酸酯）二醇（PHBD）为原料，采用六亚甲基二异氰酸酯作为交联剂制备了可生物降解聚氨酯（PUs）。通过改变反应时间，使细菌聚羟基丁酸酯（PHB）与乙二醇进行酯交换反应，合成了不同分子量的PHBD。利用傅里叶变换红外光谱和质子核磁共振光谱对合成的PHBD进行了表征。制备了一系列不同NCO/OH和CO/PHBD比例的PUs。然后对所得的基于CO/PHBD的PUs的力学性能和热性能进行了表征。与纯CO基PU相比，增加PHBD含量可使基于CO/PHBD的PUs的拉伸强度显著提高300%。与由长链PHBD制备的PUs相比，由短链PHBD合成的基于CO/PHBD的PUs表现出更高的拉伸强度。扫描电子显微镜分析表明，所得PUs刚度的这种提高是由于CO和PHBD之间具有良好的相容性。增加PHBD含量也提高了所得PUs的结晶度。此外，与纯CO PU和由短链PHBD制备的PUs相比，由长链PHBD合成的基于CO/PHBD的PUs具有更高的降解速率。
