聚己内酯聚氨酯预聚体增容壳聚糖/聚己内酯复合材料的结构与性能研究

Structures and Properties of Chitosan/Polycaprolactone Composites Compatibilized with Polycaprolactone-Based Polyurethane Prepolymer

以聚己内酯聚氨酯预聚体(PUP)为增容剂,采用熔融法制备了壳聚糖(CS)/聚己内酯(PCL)复合材料,探究了PUP含量和PCL分子量对CS/PCL复合材料结构及性能的影响。结果表明,PUP分子上的异氰酸酯基团可以与CS分子上的羟基和氨基反应形成共价键,同时PUP与PCL相似相容,通过PUP与两相的相互作用可以有效提高CS与PCL之间的界面相容性;随着PUP含量的增加,复合材料的热稳定性和力学性能增强,当PUP含量为20%、PCL分子量为40000时,复合材料的断裂强度从15.94 MPa增至33.60 MPa,断裂伸长率从1.0%升至18.4%;PCL的分子量越高,PCL与CS的界面相容性越低。该研究为壳聚糖基复合材料的热塑加工制备及其应用奠定了一定的理论基础。

Taking polycaprolactone-based polyurethane prepolymer(PUP)as a compatibilizer,we prepared chitosan(CS)/polycaprolactone(PCL)composites by a melting method,and investigated the effects of PUP content and molecular weight of PCL on the structures and properties of CS/PCL composites.The results show that the isocyanate groups on PUP molecules can react with the hydroxyl and amino groups on CS molecules to form covalent bonds.Meanwhile,PUP and PCL are similar and compatible,the interface compatibility between CS and PCL can be effectively improved through the interaction between PUP and the two phases.With the increase of PUP content,the thermal stability and mechanical properties of the composite increase.When the PUP content is 20%,and the PCL molecular weight is 40000,the fracture strength of the composite increases from 15.94 MPa to 33.60 MPa,and the elongation at break increases from 1.0%to 18.4%.The higher the molecular weight of PCL is,the lower the interfacial compatibility between PCL and CS will be.The study lays a theoretical foundation for the preparation and application of CS-based composites in thermoplastic processing.