硬聚氯乙烯挤出结构泡沫的流变行为研究

Study of the Rheological Behavior of Rigid PVC Extrusion Structural Foam

使用直接装在普通单螺杆挤塑机上的毛细管状机头,研究了RPVC挤出结构泡沫RPVC-EF的流变行为。结果表明:含有AC发泡剂的PVC熔融物的流变行为具有假塑性流体的特性,可以表示为Ss=K(Sr)~n的指数关系,其流动行为指数n<<1;机头口模的进口角α、直径d和长度L对RPYC-EF的流变行为有强烈影响;当α为90°,L/d=3～5/1,能获得密度<0.8g/cm^3的良好制件。

With a capillary die directly fixed in general single screw extruder, the rheological behavior of RPVC extrusion structural foam (RPVC-EF) was studied, The results show that the rheological behavior of PVC melt with AC foaming agent appears to be pseudoplasic fluid characteristic, and it can be expressed as Ss=K·(St)~n, flow beharior index n(?)1, that the entrance angle α, diameter d and length L of an extrusion die has a strong influence on the rheological behavior of RPVC-EF; and when α=90°, L/d=3～5:1 can achieve an excellent product with density lower than 0.8g/cm^3.