Technologies for Quality Improvement of the Injection Molded Polymer Products Utilizing the Heat Transfer Control Technique

利用传热控制技术提高注塑聚合物产品质量的技术

基本信息

批准号：
03555041
负责人：
KUROSAKI Yasuo
金额：
$ 10.18万
依托单位：
Tokyo Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Developmental Scientific Research (B)
财政年份：
1991
资助国家：
日本
起止时间：
1991 至 1992
项目状态：
已结题

项目摘要

The main purpose of this research project is to develop the technologies for improvement of the quality of injection molded polymer products by utilizing the heat transfer control techniques, Which have been used only for maintaining the mold wall temperature uniform. The obtained results can be summarized into the followings:1. Phenomena occurring in the Packing-Holding Process and Control of Sink Mark Location by Controlling the Mold Wall Temperature Distribution. First of all, the phenomena occurring in the packing-holding process, which is used to be applied for reducing the sink mark generation, were investigated by means of visualization. And then, the control technique of the sink mark location by controlling the mold wall temperature distribution was examined under the packing-holding process. So as to apply the control technique for the practical molding, we tried to control the mold wall temperature distribution by changing the mold wall materials, which have the different thermal diffusivities, and the effectiveness of this method was confirmed.2.Rheological Examination of the Generation of Residual Stress and Molecular Orientation within the Injection Molded Polymer Products. The residual stress and molecular orientation are strongly affected both by the generation rate, i.e., cooling rate, and by their relaxation during the cooling process. In the injection molded polymer products, the generation of residual stress and molecular orientation shows complicated behaviors, because the cooling rate of the polymeric material varies in the thickness direction. From this point of view, generation process of the residual stress and molecular orientation was examined with the rheological approach. The results showed that the residual stress and molecular orientation frozen in the molded polymer can be controlled by controlling the cooling conditions through the molding processes.

该研究项目的主要目的是开发利用传热控制技术来提高注塑聚合物产品质量的技术，该技术仅用于保持模具壁温度均匀。所得结果可概括为： 1．保压过程中出现的现象以及通过控制模壁温度分布来控制缩痕位置。首先，通过可视化的方式研究了用于减少缩痕产生的保压过程中发生的现象。然后，研究了保压过程中通过控制模壁温度分布来控制缩痕位置的技术。为了将该控制技术应用到实际成型中，我们尝试通过改变具有不同热扩散率的模壁材料来控制模壁温度分布，并验证了该方法的有效性。2.流变学检查注塑聚合物产品中残余应力和分子取向的产生。残余应力和分子取向受到生成速率（即冷却速率）及其在冷却过程中的松弛的强烈影响。在注塑聚合物产品中，由于聚合物材料的冷却速率在厚度方向上变化，残余应力和分子取向的产生表现出复杂的行为。从这个角度来看，用流变学方法研究了残余应力和分子取向的产生过程。结果表明，通过控制成型过程中的冷却条件，可以控制成型聚合物中冻结的残余应力和分子取向。