影响熔喷料聚丙烯熔体流动速率测试精密度的因素

采用熔体流动速率仪检测熔喷料聚丙烯材料的熔体流动速率,考察了三种不同熔喷料聚丙烯在不同测试条件下的熔体流动速率测试精密度的影响因素,结果标明当仪器恒温预热时间大于30 min、样品加入量8 g、料筒使用氮气吹扫8 s以上、精确控制仪器温度、装料时间控制在50~60 s以内、采用较小活塞位移距离并增加取样次数时,会大大提高测试结果的精密度。

Study on the Factors Affecting the Measurement Precision of Melt Flow Rate of Meltblown Polypropylene

Melt flow rate of meltblown polypropylene was measured by melt flow rate meter,and the influencing factors of melt flow rate test precision of three different meltblown polypropylene under different test conditions were investigated.The results showed that the precision of test results could be greatly improved when the preheating time of the meter was longer than 30 min,the amount of sample was 8 g,the cylinder was purged with nitrogen for more than 8 s,the temperature of the meter was accurately controlled,the charging time was controlled within 50~60 s,the piston displacement distance was smaller and the sampling times were increased.