Study on Quality Improvement Techniques for Injection-Molding of Polymer Utilizing Heat Transfer Control

利用传热控制的聚合物注射成型质量改进技术研究

基本信息

批准号：
06555058
负责人：
KUROSAKI Yasuo
金额：
$ 8.64万
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：
1994
资助国家：
日本
起止时间：
1994 至 1995
项目状态：
已结题

项目摘要

In this study, radiation heating of the polymeric materials was investigated as the active controlling technique for cooling of moldedpolymer within the mold. In order to obstruct the cooling of polymer melt injected into the cold mold cavity, polymer melt in the cavity was heated by using CO2 laser during the filling stage of the injection-molding process, and the effects of radiation heating on the quality of molded polymer was experimentally examined. The results can be summarized as follows :(1) Quality Improvement due to Radiation Heating : Radiation heating technique was adoptedto produce a polystirene strip, and the quality of molded polymer was investigated. The obstruction of cooling due to radiation heating results in reducing the failures originated from solidification of polymer melt during the filling stage, such as residual birefringence frozen in surface region of molded strip, short-shot due to increasing the viscosity of polymer melt, lowering the transcribability of strip surface, etc.(2) Temperature Profiles in the Polymer Irradiatedby InfraredLaser : Temperatureprofile within the polymer melt irradiatedby infraredradiation is determinedby the relation between radiation absorption within the polymer and conductive cooling due to contact with the cold mold wall. In order to obtain the understandings about the temperature profiles under the irradiation condition, heat transfer within the polymer was numerically examined. The results showed that the temperature within the molded polymer is strongly affected by the relation between the monochromatic absorption coefficient of polymer material and wavelength distribution of the heating infraredradiation, and that, under the realistic condition, heating effect due to infraredradiation penetrates about 0.5-1mm from the polymer surface.

在这项研究中，研究了聚合物材料的辐射加热作为模具内模制聚合物冷却的主动控制技术。为了阻碍注入冷模具型腔的聚合物熔体的冷却，在注射成型过程的填充阶段使用CO2激光对型腔内的聚合物熔体进行加热，并研究辐射加热对成型聚合物质量的影响进行了实验检验。结果可概括如下： (1)辐射加热带来的质量改进：采用辐射加热技术生产聚苯乙烯带材，并对模制聚合物的质量进行了研究。由于辐射加热而阻碍冷却，从而减少了填充阶段聚合物熔体固化引起的故障，例如模制带材表面区域残留的双折射冻结、由于聚合物熔体粘度增加而导致的短射、降低了(2) 红外激光照射的聚合物内的温度分布：红外辐射照射的聚合物熔体内的温度分布由聚合物内的辐射吸收与传导冷却之间的关系决定。与冷模具壁接触。为了了解辐照条件下的温度分布，对聚合物内的传热进行了数值研究。结果表明，模塑聚合物内部的温度受聚合物材料的单色吸收系数与加热红外辐射的波长分布之间的关系的强烈影响，并且在实际条件下，红外辐射的加热效应可穿透约0.5-1mm。从聚合物表面。