Optimal injection parameters for multiple qualities in poly lactic acid/nano mica composites

Abstract

This study melted and mixed poly lactic acid and nano mica into a new nano composite material for injection molding. The injection parameters for the mixture included the melting time, screw speed, heating plate temperature, nano mica content, melting temperature, nozzle temperature, holding pressure, and injection speed. The quality considerations of the new nano composite material were ultraviolet (UV) absorption rate, far-infrared absorption rate, Rockwell hardness, and flame resistance. This study applied main effect analysis and variance analysis theory of the Taguchi method to analyze the single quality characteristic of the experimental results. The optimal factors and level combination was identified through multi-quality integration using the Analytic Hierarchy Process. After consistent examination and calculation of the total weighting of various parameter levels, as well as the ranking of the parameter levels, the optimal injection parameters were obtained. According to the confirmation experiment results, the Signal-to-Noise ratio of the four qualities for the new nano composite fell within the 95% confidence interval, indicating the experiment was reproducible and reliable. The results indicated that the best qualities for the new nano composite are UV absorption rate at 98.22%, far-infrared absorption rate at 90.53%, Rockwell hardness at 108.07, and the limiting oxygen index for fire resistance rating at 30.