Development of Advanced Water-Assisted Injection Molding System and Its Applications in the Processing of Engineering Plastics

The proposed project is to experimentally develop advanced water assisted injection molding system and to investigate the moldability of engineering plastics such as Nylon and glass fiber reinforced Nylon composites. The total research works can be divided into three different stages and be completed in three years. The research will develop a new lab-type water assisted injection unit. Combined with the existing injection molding machine, the research will design a new general water assisted injection unit that features the ability of molding thin and thick parts as well as the auto-removal of water after molding. The research will also discuss the effects of melt temperature, mold temperature, melt filling speed, melt filling pressure, water pressure, and water injection delay time etc. on the quality of molded Nylon and Nylon composites. The research will also investigate the effect of polymer』s rheological properties on molded properties and the total cycle time of the liquid assisted injection molding process. The project will include a four-stage research. The first stage is to design and develop a novel water assisted injection unit. The unit will include a high-pressure water pump, a piping system, a water injection system, a control system as well as a new mechanism for water removal. The second stage 「Optimization of the Mold and Process」 is to find out, through different experiments, the effect of melt temperature, mold temperature, melt filling speed, melt filling pressure, water pressure, water injection delay time etc. on the quality of molded products. The third stage 「The Influence of rheological Properties」 is to discuss the effect of polymer rheological properties on the molded products and the total cycle time of the liquid assisted injection molding process. The final stage will be to observe the filling process of liquid assisted injection molding and how the molding problems occur inside the cavity. The final goal of this research is to further understand the molding problems in liquid assisted injection molded polymers so that the optimum conditions can be obtained. It is also hoped that the optimum processing conditions obtained in this research can be used as a reference by the molders so that the overall liquid assisted injection molding techniques can be promoted.

Project ID:PB9708-0125
External Project ID:NSC95-2221-E182-032-MY3