权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

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内聚合物冷却的主动控制技术。为了阻止冷模腔内聚合物熔体的冷却，在注射成型的充模阶段，利用CO2激光器对型腔内的聚合物熔体进行加热，并实验研究了辐射加热对成型聚合物质量的影响。主要研究结果如下：(1)辐射加热的质量改进：采用辐射加热技术生产了聚苯乙烯带材，并对模塑聚合物的质量进行了考察。由于辐射加热造成的冷却受阻，导致减少了填充阶段由于聚合物熔体凝固而产生的失效，如在模条表面区域冻结的残余双折射、由于增加聚合物熔体的粘度而导致的短射、降低条带表面的可转录能力等。(2)红外激光照射的聚合物中的温度分布：红外辐射照射的聚合物熔体内的温度分布由聚合物内部的辐射吸收和由于与冷模壁接触而导致的传导冷却之间的关系决定。为了了解辐照条件下的温度分布，对聚合物内部的热传递进行了数值模拟。结果表明，聚合物材料的单色吸收系数与加热红外辐射波长分布的关系对模塑聚合物内的温度有很大的影响，在实际条件下，红外辐射加热效应可穿透到距聚合物表面约0.5~1 mm处。