Study On The Structure And Properties Of PTT/PC Blends And The Blended Fiber

Polytrimethylene（PTT） is a new type of thermoplastic developed after the Polyethylene terephthalate（PET） and polybutylene terephthalate（PBT） which is widely used as engineering plastic.Polycarbonate（PC） which is used as thermoplastic has an excellent performance but it also has some shortcomings.In this article,not only the compatibility of PTT/PC blends,but also the structure and properties of this system were studied.First of all,by using DSC,Infra-red spectrum,X-ray diffraction and SEM,the compatibility of PTT/PC blends was studied.It was found the PTT/PC blends was thermodynamics partly compatible blends and the blends system was partly compatible both in the amorphous and crystalline area.The infra-red spectrum test proved there is transesterification during the blend process.Secondly,the crystallization properties and the non-isothermal crystallization dynamics of PTT/PC blends were studied by DSC test.The adding of PC could increase the cold crystallization temperature of PTT.The cooling curve of DSC and POM pictures proved the crystallization ability reduced a lot when the PC component in the majority.To the PTT/PC blends system,the half-time of crystallization(t_1/2) and the value of T_c（the temperature corresponding to the exothermic peak） decreased with the cooling rate increasing;the Avrami index decreased with the PC content increasing.The rheological behavior of PTT/PC blends in different ratio was studied by ARES-RFS rheometer.The test results showed the PTT/PC blends system was non-Newton fluid and was the stress attenuation,meanwhile the dynamic viscosity decreased and the non-Newton index increased when the temperature rise.The flow-activation energy of the system appeared decrease with the content of PTT increasing. The experiment indicated the impact strength and tensile strength of PTT/PC blends appeared the maximum value with the PTT content increasing and became decrease after that.The TGA results showed the thermal-decompostion temperature of PTT/PC blends has no advantage compare to the pure PC and PTT.According to the spinning test results on PTT/PC blends,when the content of PC was under fifty percent,the tensile strength of PTT/PC fiber was increased with the adding of PC content,and the recovery was also favorable.