硅烷接枝聚乙烯的加工流变性能

The Rheological Property of Vinyl Silane Grafted Polyethylene

采用HAAKE流变仪作为反应器,将不饱和硅烷熔融接枝到低密度聚乙烯(LDPE),制得硅烷接枝聚乙烯,然后将该接枝料用于毛细管流变测试和熔体流动速率测试。实验结果表明,转速越高,扭矩曲线的峰值越大,达到最高峰的时间越短,并且料温上升也越快。毛细管流变测试表明体系为假塑性流体,表现出典型的切力变稀行为。随着剪切速率的增大和温度的升高,表观黏度都呈下降趋势。随着剪切速率的增大,体系的表观黏度对温度的依赖性减小。熔体流动速率(MFR)测试表明,硅烷接枝PE的MFR随引发剂用量的增多而减小,但并非呈线性关系。

Polyethylene was melting grafted with vinyl silane in the reactor of HAAKE Rheometer. HAKKE and capillary Rheometer were used for reasearching rheological behavior of vinyl silane grafted polyethylene. The results indicate that with the increasing of the rotating speed, the peak value in the torque curves increases and the time reaching torque peak in curves is in advance, meanwhile the stuff temperature rise more rapid. Capillary rheological property tests show that the vinyl silane grafted polyethylene are pseudo-plastic fluid, and the behavior of obvious shear thinning was observed; the results show that the increasing of temperature or shear rate would make the apparent melt viscosity decrease And as increasing of shear rate, the dependence of shear viscosity on temperature is decreased. MFR tests indicate that the MFR of vinyl silane grafted polyethylene is decreased along with the increase of DCP content, but not in accord with linear relationship.