聚乙烯透气膜专用料的组成与性能研究

Investigation on Composition and Properties of Specialized Formula Materials for Polyethylene Breathable Films

为了优化聚乙烯透气膜专用料的生产配方,提高其加工流动性以及透气膜性能,从分散树脂熔体流动速率、碳酸钙粒径大小、分布及用量的角度,研究了透气膜专用料组成对其加工流动性以及透气膜性能的影响。使用毛细管流变仪测定专用料的流动性,通过测定孔隙率、透气率和拉伸强度表征微孔膜的性能。结果表明,使用熔体流动速率为50 g/10 min的LDPE作为分散树脂使专用料拥有更好的流动性,并且明显改善透气膜的孔隙率和透气率;降低碳酸钙粒径可以提高透气膜的拉伸强度,适当增加碳酸钙粒径及分布宽度则可以提高透气膜的孔隙率和透气率;随着专用料中碳酸钙含量从40%增加到55%,透气膜的拉伸强度下降约20%,但孔隙率从36.1%增加到46.9%,透过性能大幅度提高。

In order to optimize the recipe of specialized formula materials for polyethylene breathable films, as well as to improve the process ability of the specialized formula materials and permeability of the resulting breathable films, the effects of composition of specialized formula materials on its flow ability and the performance of the breathable films were investigated, with respects to flow ability of dispersion resins, particle size, size distribution and the usage of CaCO3. Capillary rheometer was used to characterize rheo- logical behavior of the specialized formula materials, and the performance of breathable films was charac- terized by measurements of porosity, air permeability and tensile strength. The results showed that LDPE with melt flow rate of 50g/10min as dispersion resin could promote flowability of the specialized formula materials, and the porosity and air permeability of the resulting breathable films were improved obviously. Reducing particle size of CaCO3 led to an increased tensile strength of the breathable films, while a proper increase of particle size and distribution of CaCO3 led to increased porosity and air permeability of the breathable films. As the CaCO3 content in the specialized formula materials increased from 40 % to 55 %, the tensile strength of the breathable films dropped about 20%, while the porosity was increased from 36.1% to 46.9%.