聚丁二酸丁二醇酯和聚辛二酸丁二醇酯及聚(丁二酸-co-辛二酸丁二醇)共聚酯的酶促降解

Enzymatic Hydrolysis of Polybutylene Succinate,Polybutylene Suberic Acid and Poly(butylene succinate-co-butylene suberate)

以1,4-丁二醇与不同链长二元酸单体为原料,合成了聚丁二酸丁二醇酯(PBS)和聚辛二酸丁二醇酯(PBSub)2种均聚酯和4种不同比例聚(丁二酸-co-辛二酸丁二醇)共聚酯。以上述6种聚酯为降解底物,利用角质酶对其进行降解研究。通过衰减全反射傅里叶变换红外光谱、核磁共振波谱仪、差示扫描量热仪、X射线衍射仪和热重分析仪等对聚酯及其降解产物进行表征分析。6种聚酯的晶体结构、熔点、结晶度和热稳定性变化不大。研究表明,聚酯的结晶度和熔点温度是影响其酶降解的重要因素。角质酶降解共聚酯的结晶区和非结晶区,但优先降解非结晶区。丁二酸/辛二酸投料摩尔比为4/6和6/4的降解效果最好,但摩尔比为6/4的样品熔点较高,为最佳比例。

Two kinds of homopolyesters,polybutylene succinate(PBS)and polybutylene octoate(PBSub),and four kinds of poly(butylene succinate-co-butylene suberate)copolyesters with different ratios,were synthesized from 1,4-butanediol and different chain length dicarboxylic acid monomers.Using the above six types of polyester as degradation substrate,the degradation of them was studied using keratinase.The polymers and their degradation products were characterized and analyzed by attenuated total reflection Fourier transform infrared spectroscopy,nuclear magnetic resonance spectroscopy,differential scanning calorimetry,X-ray diffraction,and thermogravimetric analysis.The crystal structure,melting point,crystallinity,and thermal stability of the six polyesters have little change.Research show that crystallinity and melting point temperature of polyester are important factors impacting enzymatic degradation of polyester.The degradation of the copolyesters by keratinase arises in the crystalline and amorphous regions,but the amorphous regions are degradating priority.The degradation effect is best when the mole ratio of succinic acid to octanedioic acid is 4/6 and 6/4,but the sample with a mole ratio of 6/4 has a higher melting point,which is the best ratio.