| Polymer nanocomposites have great market prospects due to the fact that polymer nanocomposites have special advantage in optics,price magnetism,mechanics,thermal,and electrical properties and that nano-particles are inexpensive.But the research on polymer nanocomposite was mostly concentrated on the mechanical properties,dimensional stability and permeability of the polymer.The influence of thermal history on the polymer nanocomposites' crystalliza behavior was rarely mentioned.However,the influence of thermal history on the polymer nanocomposites' crystalliza behavior is of great value for polymer processing and special modification.In this thesis,PA6/nano-silica nanocomposites were prepared by the method of melt intercalation.Nano-silica were well dispersed in the PVDF matrix.Nano-silica nanoparticles modified by KH602 promoted the aggregation of nano-silica in nylon 6 matrix,and nano-silica modified by KH560 promoted the dispersion of nanoparticles in nylon 6 matrix.The results indicate that lower heating rate,lower cooling rate and longer annealing time are helpful in terms of improving the toughness of y-type crystal in the crystalline proportion.PA66/clay nanocomposites were prepared by the method of melt intercalation.clay nanocomposites were well dispersed in the PA66 matrix.However,with the increase of clay nanocomposites content,there was aggregation tendency.PA66/clay nanocomposites prepared by the phase inversion method were stratified.The results indicate that by lower heating rate and cooling rate,as well as providing a longer time in solid-state annealing are helpful for improving the toughness of ?-type crystal in the crystalline proportion.Then,under conditions of high temperature annealing,long annealing time were more conducive to the formation of a-type crystal.PVDF/nano-silica nanocomposites were prepared by the phase inversion method.Nano-silica were well dispersed in the PVDF matrix.But the PVDF nanocomposites had no crystalline transformation. |
PDF Full Text Request