PC/ABS流长比测试影响因素研究

Research on the Influencing Factors of PC/ABS Melt Flow Ratio Testing

流长比评估材料流动性与注塑生产关联性高,但流长比测试中经常出现数据稳定性差的问题。本文研究了影响PC/ABS材料流长比的注塑工艺因素,并与熔融指数和剪切黏度进行了对比。研究发现:料温和压力提高,停留时间加长,流长明显增加;模温提高,流长略提高;射出模式下射速和射压提高,流长提高,而射出时间提高,流长先增加后趋于稳定;保压模式下保压压力提高,流长提高,而保压速度和时间提高,流长先增加后趋于稳定。熔融指数和剪切黏度变化趋势一致,与流长比数据在低温段变化趋势一致,在高温段差异较大,290℃时对比样比3号MFR大6%,黏度大4.5%,但流长比小11%。

Flow-length ratio that evaluate material flowability,can be related to injection molding processing,but the result is unstable.In this paper,the factors affecting the flow-length ratio of PC/ABS were studied and compared with the melt index and shear viscosity.The results show that the flow length increases significantly with higher melt temperature and pressure and residence time,increase slightly with higher mold temperature.In the injection mode,higher injection speed and pressure result in higher flow length,flow length increase firstly then stable with injection time.In the holding mode,the flow length increases with higher hold pressure,while the flow length increases then stable with the increase of velocity and time.The change trend of melt index and shear viscosity is same,and same with flow length ratio in low temperature,but it is different in high temperature,the contrast sample’s MFR is 6%larger and viscosity 4.5%bigger,but the flow length is 11%smaller than 3#at 290℃.