摘要
本文介绍了硬PVC的注塑成型技术在电子领域中的应用。对所用树脂、配方设计、注塑成型设备与工艺进行了探讨。认为用于注塑成型的PVC树脂应有较低的粘度(K值为50～52)、较高的孔隙率、白度必须在92%以上。所得理想的配方为:PVC100份,稳定剂5.8份,润滑剂2份,加工助剂3.5份,冲击改性剂5份,增塑剂5份,醋酸乙烯酯共聚物4份。配方物的冲击强度为11.5kJ/m^2,拉伸强度41MPa,热变形温度70℃。宜用螺杆式注塑机注塑。所制硬PVC收录机音箱后盖的工艺条件为:注塑温度:95～190℃,注射压力:9.5～10MPa,保压压力:4.0～4.5MPa,背压0 7～1.0MPa,螺杆转速:25r/min,模温:40～45℃。
The application of injection moulding technology of rigid PVC to electronic industry, the specification for the resin,the formulating of recipe, the machinery and technology for the injection moulding were introduced in this paper. It was con-sidered that the PVC resin for the moulding should have a low viscosity (K should be 50～52) and high porosity, the resinwhiteness should be more than 92%. An ideal formula suggested for the moulding is: PVC 100 parts, stabilizer 5. 8 parts, lu-bricant 2 parts, process aid 3. 5 parts, impact modifier 5 parts, plasticizer 5 parts, EVA 4 parts, and proper contents of assitants such as ultraviolet absorber. The impact strength of the prepare? product is 11.5 kJ/m^2, tensile strength 41 MPa,thermal deformation temperature 70℃. It was better to use screw injection moulder for the processing, and the technical condi-tions for the moulding of the back cover of the cassette of tape recorder with rigid PVC is as follows: temperature 95～190℃,injection pressure 9. 5～10 MPa, holding pressure 4. 0～4. 5 MPa, back pressure 0. 7～1. 0MPa, screw speed 25 r/min,mould temperature 40～45℃.
出处
《塑料工业》
CAS
CSCD
北大核心
1990年第1期23-25,43,共3页
China Plastics Industry
