Study On The Spinnability Of PET/PA6/MMT Nanocomposites And Their Structure And Properties

Polymer/montmorillonite nanocomposites have attracted considerable attention in academic and industrial circles due to their many outstanding performances, and become a hot subject in the polymeric material field in recent years. The studies and applications in plastic area of polymer/montmorillonite nanocomposites have been reported a lot, but as for the material, especially the study of spinnability and their structure and properties of blend polymer/ montmorillonite have been few reported.In this thesis, the nanocomposites based on PET/PA6/MMT were prepared by one-step and two-step melt intercalated mixing in a twin-screw extruder. Their structures were examined by WAXD and SEM methods. The nonisothermal crystallization kinetics and the compatibilization of PET/ PA6/MMT were studied by DSC method. The spinnability of the PET/PA6/MMT blends systems with different contents, the mechanical properties and dyeing kinetics and dyeing thermodynamics of the fibers prepared were studied. The main results obtained are as follows:1. The nanocomposites based on PET/PA6/MMT were prepared by different methods and their structures were characterized by WAXD and SEM methods. The results indicated that it is practical to prepare the exfoliated PET/PA6/MMT nanocomposites via both one-step and two-step melt intercalated mixing in a twin-screw extruder.2,The nonisthermal crystallization kinetics was studied by DSC method. The results indicated that when the content of PA6 is lower than 20%, the half time of crystallization is shorter than that of pure PET and the rate of crystallization is faster than that of pure PET. When the content of PA6 is higher than 20%, the half time of crystallization is longer than that of pure PET and the rate of crystallization is smaller than that of pure PET. When the content of PA6 is 10%, no matter by one-step or two-step melt intercalation, the relative degree of crystallinity had been improved obviously. However, with the content of PA6 higher, the compatibilzation of PET and PA6 became worse. The effect of the cooling rate on relative degree of crystalliinity is great.3,The compatibilization results of the PET/PA6/MMT blend system indicated that the PET and PA6 phase in the blend system became partly compatibilization with a little content of MMT as a compatilizer. However, when the amount of MMT is larger than 4%, the dispersion of MMT in the matrix will be affected. The compatibilizer of blend system with EPOX was also improved, and the larger the content of PA6, the better of the system compatibilization.4,The spinnability and the dyeing properties of PET/PA6/MMT blend system was studied in detail. The results indicated that the composition of 90/10/2 PET/PA6/MMT has good spinnability, the spun fiber from which has better dyeing properties. The result of dyeing kinetics of the fibers indicated that the adsorption isothermal curves of PET/PA6/MMT fibers under different dyeing temperature belong to the distribution type. The result of dyeing thermodynamics of the fibers indicated that the diffusion index became higher as the dyeing temperature.