纺丝组件中多孔介质对PA6熔体流动性能的影响

Effect of porous media on flowability of PA6 melt in spinning pack

在毛细管流变仪上增加多孔介质金属过滤砂,研究了聚己内酰胺(PA6)熔体通过不同过滤精度的多孔介质时的流动规律。结果表明:随着多孔介质过滤精度与熔体流动速率的增大,PA6熔体的压力增加值增大;PA6熔体压力增加值与流动速率关系可用Forchheimer方程较好地描述,其方程的拟合相关系数均大于0.997,粘性阻力因子(1/k)与惯性阻力因子(β)都随多孔介质过滤精度的增加而增加,当温度为265℃时,β较1/k大2个数量级;随着熔体温度的升高,1/k与β均减小;在实验条件下,PA6熔体的压力增加值主要来自粘性损耗,但随着流动速率的增加,惯性损耗增加,过滤精度越高,惯性损耗增加越明显。

The flowing law of polycaprolactam （PA6） melt through porous media with different filtration precision was studied with a capillary rheometer filled with metal filter sand. The results showed that the pressure growth of PA6 melt was increased with the increase of filtration precision and melt flow rate; Forchbeimer equation accurately described the relationship between the pressure growth and the flow rate of PA6 melt, the fitting correlation coefficient was above 0. 997 ; the viscous resistance factor （1/k） and inertial resistance factor （ β ） were both increased with the increase of the filtration precision of porous media; β was two orders of magnitude larger than 1/k at 265℃ ; 1/k and β beth decreased with the elevation of melt temperature; the pressure growth of PA6 melt was mainly attributed to viscous loss under experimental conditions, which was increased with the increase of flow rate; and the higher the filtration precision, the greater the inertial loss growth.