聚己内酯(PCL)改性PET/N100黏合剂的力学性能

To improve the mechanical properties of the ethylene oxide tetrahydrofuran copolyether (PET)/N100 binder system, polycaprolactone (PCL) was introduced into PET/N100 system. Differential scanning calorimetry (DSC), fourier transform infrared spectroscopy (FTIR), low field nuclear magnetic (LF-NMR) and mechanical tensile tests at different temperatures were used to analyze the effect of PCL content on the mechanical properties of PET/N100 system.The results show that the glass transition temperatures of modified binder systems with different PCL contents are all below -60℃, while the elongation is still 560.4% at low temperature. The increase of PCL content makes the number of hydrogen bonds in the system increase sharply, and the content of high temperature resistant cross-linked parts in the cross-linked network increase, so the high-temperature mechanical strength of the binder improves. Compared with the blank sample, the breaking strength of the binder film with 50% PCL content increases from 1.26MPa to 1.95MPa at 25℃, and the breaking strength reaches 1.93MPa at 60℃. When temperature continues to rise to 80℃, the breaking strength is 1.84MPa, indicating that the addition of PCL can greatly improve the mechanical strength of PET binder at high temperature while maintaining the elongation at low temperature.