聚2,5-呋喃二甲酸乙二酯的合成及性能

Synthesis and Characterization of Poly(ethylene 2,5-furandicarboxylate)

以生物基2,5-呋喃二甲酸(FDCA)和乙二醇(EG)为原料,钛酸四丁酯为催化剂,经直接酯化法制备聚2,5-呋喃二甲酸乙二酯(PEF).采用傅里叶变换红外光谱(FTIR)和核磁共振氢谱(1 H-NMR)分析PEF的分子结构,研究不同醇酸摩尔比对PEF合成动力学的影响,并探讨了PEF的热性能及结晶性能.研究结果表明:PEF的酯化反应速率、缩聚反应速率和特性黏度均在醇酸摩尔比为1.8时达到最大值;随着醇酸摩尔比、缩聚时间的增加,PEF的冷结晶温度(tcc)增加,熔融温度(tm)和热结晶温度(tmc)降低,PEF的结晶能力明显减弱.PEF为半结晶型聚合物,经熔融淬冷后结晶度降低,且降温速率较快时,表现出较小的结晶度.

Poly（ethylene 2, 5-furandicarboxylate） （PEF） polyester was synthesized by bio-based 2,5- furandicarboxylic acid （FDCA） and ethylene glycol （EG） through polycondensation. Tetrabutyl titanate was adopted as catalyst. The molecular structure of PEF was characterized with Fourier transform infrared spectroscopy （FTIR） and nuclear magnetic resonance spectroscopy （1H-NMR）. The kinetics of polycondensation, crystallization and thermal properties of PEF prepared at different mole ratios of EG to FDCA were investigated. It is found that the esterification rate, polycondensation rate, and intrinsic viscosity of PEF all reach to the maximum value when the mole ratio of EG to FDCA is equal to 1.8. The cooling crystallization temperature （ t cc） of PEF increases rapidly with the increasing of the mole ratio of EG to FDCA and polycondensation time. The melting temperature （tm） and heating crystallization temperature （tmc） of PEF have a slight decrease with increasing the mole ratio of EG to FDCA and polycondensation time. However, the crystallization capacity is weakened significantly due to the excess EG and increasing polycondensation time. PEF is a semicrystalline polymer,so the crystallinity of PEF is reduced by heating, and it shows lower crystallinity after quenched with high cooling rate.