注塑工艺对PC/ABS合金电镀性能的影响研究

对聚碳酸酯(PC)/丙烯腈-丁二烯-苯乙烯(ABS)合金采用使用不同的注塑工艺注塑后电镀。研究了注塑工艺对PC/ABS合金粗化性能和镀层结合力的影响。结果表明:注塑工艺对PC/ABS合金的粗化性能和镀层结合力影响较大,注塑温度过低、压力和速度过高以及模具温度过低都会降低PC/ABS合金的粗化性能和镀层结合力。     

车灯装饰圈用PBT/PET合金的成型加工

研究了聚对苯二甲酸丁二醉酯/聚对苯二甲酸乙二醇酯(PBT/PET)合金的流变特征;并结合PBT/PET合金的特点,研究了干燥工艺、模其设计、注塑设备选择、注塑加工工艺对制品性能的影响,对优化PBT/PET合金材料的注塑工艺条件具有指导意义.     

RPVC/ABS合金的润滑体系研究

研究了不同种类的润滑剂对硬质聚氯乙烯/丙烯腈-丁二烯-苯乙烯共聚物(RPVC/ABS)合金流变性能的影响。结果表明:低熔点的润滑剂和石蜡对RPVC/ABS合金的塑化性能影响很小,并且石蜡与ABS的相容性很差,非常容易析出,限制了其在RPVC/ABS合金中的应用;高熔点的润滑剂可明显延长合金的塑化时间,降低平衡扭矩。在相同试验条件下,润滑剂A的外润滑效果明显好于乙撑双硬脂酰胺(EBS)的。注塑试验发现,添加润滑剂A的RPVC/ABS合金具有良好的注塑加工性能,并且注塑样片的白度提高,黄色指数降低,可以满足合金的长周期注塑要求。     

注塑工艺对PC/ASA合金光泽度的影响

对通用级和哑光级聚碳酸酯/丙烯晴–苯乙烯–丙烯酸酯三元共聚物(PC/ASA)合金采用不同的注塑工艺注塑样板,研究了注塑工艺中的模具温度、注射温度、注射速度和注塑压力对这两种PC/ASA合金K31皮纹面和光面光泽度的影响。研究结果表明,注塑工艺中模具温度和注射温度对两种PC/ASA合金K31皮纹面和光面光泽度影响较大,而注射速度和注塑压力对两种PC/ASA合金K31皮纹面和光面光泽度影响较小,提高模具温度和注射温度,K31皮纹面的光泽度明显降低,但光面的光泽度却明显提高。     

注塑工艺对PVC-U合金性能的影响

研究了注塑工艺对PVC-U合金性能的影响,结果表明:在注射温度185℃、注射压力80MPa、注射速度60g/s、注射时间5s的工艺条件下,注塑制品具有较好的力学性能。     

几种相容剂对PVC/ABS合金注塑料性能影响

研究了氯化聚乙烯(CPE)、乙烯醋酸乙烯酯共聚物(EVA)、甲基丙烯酸甲酯-丁二烯-苯乙烯共聚物(MBS)和丁腈橡胶(NBR)4种相容剂对聚氯乙烯/丙烯腈-丁二烯-苯乙烯共聚物(PVC/ABS)合金注塑料性能的影响。研究结果表明,4种相容剂均会降低PVC/ABS合金注塑料的弯曲性能和阻燃性;CPE和EVA综合性能较好,有利于注塑料的加工和使用;MBS和NBR对合金注塑料流动性的不利影响较大,不适用于PVC/ABS合金注塑料。     

PVC/ABS合金的热稳定性能研究

研究了影响聚氯乙烯/丙烯腈-丁二烯-苯乙烯共聚物(PVC/ABS)合金的热稳定性的3种因素,结果表明,随着ABS树脂含量的增加,合金的热稳定时间急剧缩短,ABS质量分数在20%~80%时,动态热稳定时间变化不大;随着有机锡热稳定剂用量的增加,合金的热稳定时间逐渐延长。通过对正交试验的极差分析,结果表明,有机锡热稳定剂对热稳定时间的影响最大,其次为硬脂酸钙,辅助稳定剂影响最小;随着注塑时间的延长,合金的白度变化不大,但黄色指数有逐渐增大的趋势。     

注塑模温对阻燃增强PET/PBT合金表面浮纤的影响

通过对玻纤增强材料表面浮纤的影响因素进行分析,发现模温是影响材料表面浮纤的一个重要因素。通过对不同黏度的聚对苯二甲酸丁二醇酯树脂(PBT)和聚对苯二甲酸乙二醇酯树脂(PET)搭配的阻燃增强PBT/PET合金表面浮纤的研究,发现注塑压力和模具温度对合金材料的表面浮纤都有较大的影响,高注塑压力和高模温可以显著地降低合金的表面浮纤。当采用较高的注塑模温后,合金流动性对表面浮纤的影响减弱。     

PVC-U管件粒料与粉料注塑工艺比较

比较了粒料注塑与粉料注塑2种工艺,从设备、模具、配方、工艺4个方面分析了影响粉料注塑的影响因素。     

注塑工艺对哑光PC/ABS冲击性能的影响

通过不同注塑工艺对哑光级聚碳酸酯(PC)和丙烯腈–丁二烯–苯乙烯(ABS)共聚混合物进行注塑成型,通过改变不同的注塑条件(注塑温度、模具温度、注塑压力、注塑速度),研究不同的注塑工艺对哑光PC/ABS材料抗冲击性能的影响。研究结果表明,注塑工艺变化,会引起材料冲击性能变化。其中注塑温度与模具温度对结果影响较大,注塑温度240℃,模具温度80℃时,哑光PC/ABS的冲击强度最高;在合适的注塑压力范围内,压力变化对材料冲击影响不大;合适的注塑速度范围内,注塑速度变化对材料冲击影响不大。工艺选择注塑温度240℃,模具温度80℃,注塑压力2.6~6.1 MPa,注塑速度13.9~32.3 g/s时,哑光PC/ABS冲击性能最好。因此,选用合适的注塑工艺可以提高材料的冲击性能。     

微孔注塑成型研究进展

阐述了微孔发泡成型的基本原理,综述了注射速度、注射量、模具温度、熔体温度等加工参数对微孔注塑成型的影响,介绍了常见的微孔注塑成型设备,并对微孔注塑成型的发展前景进行了展望。     

Effects of processing parameters on formation of sinkmarks on injection moulded parts

Abstract

The effects of different processing parameters on sinkmarks, which occur on the surface of injection moulded parts, have been investigated. An L'18 orthogonal array design based on the Taguchi method was conducted to minimise the sinkmarks of injection moulded thermoplastic parts and the relative significance of each processing parameter on the sinkmarks was considered. The polymeric material used was polypropylene and a plate cavity with various ribs was used for moulding. Experiments were carried out on a reciprocating injection moulding machine. After moulding, sinkmarks on the surface of moulded parts were measured using a profile meter. For the factors selected in the main experiments, the size of the gate, the melt temperature, and the width of the rib were found to be the principal parameters affecting sinkmark formation on injection moulded polypropylene. In this way experimental investigation can help in the understanding of the formation mechanism of sinkmarks, so that steps can be taken to optimise the surface quality of moulded parts.     

尼龙-11的注射成型技术

介绍了尼龙－１１的注射成型特性，制品与模具的设计、成型设备，成型工艺条件等。     

Experimental study of weldline caused by flow lead effect in gas assisted injection moulded parts

Abstract

Gas assisted injection moulding has become one of the most important methods for the manufacture of plastic products. However, there are several unsolved problems that confound the overall success of this technique. The weldline caused by the flow lead effect in the polymer melt is one of them. In this report, an L′18 orthogonal array design based on the Taguchi method has been conducted to investigate the flow lead induced weldlines in gas assisted injection moulded parts. A plate cavity with a gas channel on the side was used for moulding. Experiments were carried out on an 80 t reciprocating screw injection moulding machine equipped with a high pressure gas injection unit. After moulding, the depth of the weldline was measured. For the factors selected in the main experiments, melt injection temperature and mould temperature were found to be the principal factors affecting the weldline depth of gas assisted injection moulded parts. Experimental investigation of a gas assisted injection moulding problem can help in better understanding the weldlines caused by flow lead effects, so that steps can be taken to optimise the surface quality of moulded parts. PRC/1755     

聚碳酸酯的注射成型特点

介绍了聚碳酸酯(PC)注射成型的工艺特点,着重分析了PC注射成型前的注意事项及成型工艺条件(温度、压力、时间)的正确选择。     

注塑成型工艺对PBT收缩率的影响

论述了注塑成型中压力、温度、时间、速度等工艺条件对聚对苯二甲酸丁二醇酯注塑制品收缩率的影响,并以此为依据拟定了最佳成型工艺条件。     

共注射成型技术及其发展

介绍两种典型共注射成型技术,即双色注射和夹芯注射,以及在共注射成型基础上发展起来的气体辅助共注射成型技术和层状注射成型技术,并对各种共注射成型技术的工艺过程、优点及应用也作了介绍。讨论了双色注射成型过程中工艺参数对注射成型的影响;对夹芯注射成型过程中的芯层熔体前沿突破现象及其影响因素也进行了讨论。     

基于数值模拟的注塑模具优化及注塑成型工艺参数快速设置

以某一监控设备外壳成型为例,介绍了利用Moldflow软件优化模具结构及快速设置注塑成型工艺参数的方法,为注塑模具设计和试模时工艺参数的设定提供了依据,缩短了模具设计和试模周期。     

Variations in surface gloss on parts made by gas assisted injection moulding

Abstract

Gas assisted injection moulding has proved to be a breakthrough in moulding technology for thermoplastic materials. However, there are still unsolved problems that limit the overall success of this technique. The aim of this work was to study the phenomenon of gloss variations occurring across the surfaces of gas assisted injection moulded parts. Experiments were carried out on an 80 t injection moulding machine equipped with a high pressure, nitrogen gas injection unit. The materials used were pigmented acrylonitrile/butadiene/ styrene and polypropylene. A plate cavity with a gas channel across its centre was used to mould the parts. Various processing parameters were varied: melt temperature; mould temperature; melt filling speed; short shot size; gas pressure; and gas injection delay time. After moulding, a glossmeter was used to determine the effects of these processing parameters on the surface gloss profiles of the parts. A roughness meter and scanning electronic microscope were also employed to characterise the surface quality of moulded parts. In addition, a numerical analysis of the filling process was carried out to help better understand the mechanisms responsible for the phenomenon of surface gloss variations. It was found that the surface gloss difference occurs mainly in the transition area between channel and plate in the moulded parts, which might be the result of the shear stress gradient in the polymer melt during the filling process. Surface roughness of moulded parts might also be another factor resulting in the gloss difference problem. PRC/1720     

气体辅助注射成型技术

介绍了消除厚壁制件所出现的缩痕、凹痕缺陷的一种新型塑料成型工艺－－气体辅助注射成型技术的工作原理,技术关键、设备配置及其应用,并重点介绍了内置气体辅助成型和表面气体辅助成型技术。