Study On PP/PA6 Blending Modification Based On Interface Adjustment

With the improvement of people’s living standards,the demand for high-performance materials is gradually increasing.When developing high-performance materials,the cost of polymer blending modification is lower and the development cycle is shorter than that of developing a completely new material.For polymer blending modification,the conventional blending process involves directly melting and blending granular or powdered polymers according to the formula to produce composite materials.In most cases,premixing is simply mechanical mixing,with limited interface area growth.In order to produce composite materials with better performance,In this paper,based on the mixing theory that the larger the interface area during polymer mixing,the better the mixing effect,a new blending modification technology,namely interface adjustment blending modification technology,has been proposed.The method is explored by producing composite materials of polypropylene(PP)and Polyamide 6(PA6).The primary work and consequent are as below:1)PP/PA6 composites were produced using interface adjustment blending modification and conventional blending modification process,to explore the effect of interface adjustment blending modification.The results showed that the tensile strength and impact strength of the composite material prepared by the interface controlled blending modification process were increased by11.2 % and 8.5 %,and the dispersed phase on the impact section of the sample was flake-like,with a blurry interface between the two phases and almost no pores.This indicates that the interface adjustment blending modification process has a better mixing effect and obvious advantages compared to conventional blending modification processes.PP/PA6 composites with different formulations were produced using interface adjustment blending modification process,and changes in their comprehensive mechanical properties were investigated under different formulations.The results showed that with the increase of PA6 content,there is a trend of first increasing and then decreasing.When the formula of PP and PA6 is 70:30,the composite material has the best comprehensive mechanical property.2)In order to explore the reasons for interface controlled delamination of composite films in experiments,the flow field inside the interface adjusted die under different PP and PA6 material formulations were simulated and analyzed.The results showed that the simulation results are consistent with the experimental results..As the content of PA6 material in the formula increased,the interface velocity difference between the two melts during extrusion increased,which is consistent with the results of the delamination phenomenon of the composite film prepared in the experiment.Based on the research results of the influence of the formulation on the performance of PP/PA6 using interface controlled blending technology,the flow field inside the interface adjusted die was simulated under different feed rates.The simulation results showed that as the feeding rate increased,the interface velocity difference between PP and PA6 melted during extrusion gradually increased.3)In order to research the effect of drafting ratio on the properties of PP/PA6 composite materials,numerical simulation and experimental research were conducted.The results showed that the draft ratio increased from 3 to 7.The smaller the thickness of the composite film,the better the comprehensive mechanical properties of the composite material.Simulation and experimental results are consistent,with a 99 % decrease in film thickness,while the comprehensive mechanical properties of the composite material prepared by the experiment are improved by 41.3 %.