纳米TiO_2和纳米CaCO_3对EVAC流滴棚膜性能的影响

采用内添法,将纳米二氧化钛(nano-TiO_2)或纳米碳酸钙(nano-CaCO_3)与流滴剂司班60等助剂混合后,利用挤出机制备以乙烯–乙酸乙烯酯塑料(EVAC)为载体的流滴母粒,进而通过吹塑工艺制备EVAC流滴棚膜,探讨了nano-TiO_2或nano-CaCO_3用量对EVAC流滴棚膜拉伸性能、流滴性和透光性的影响。结果表明,适当的加入nanoTiO_2或nano-CaCO_3,均能提高棚膜的拉伸强度,当母粒中nano-CaCO_3用量为4份时,棚膜的纵横向拉伸强度达到最大,而母粒中nano-TiO_2用量为2份时,即可使棚膜的纵横向拉伸强度达到最大;nano-TiO_2的加入略微改善了棚膜的流滴性,而nano-CaCO_3使棚膜的流滴性降低;添加nano-TiO_2或nano-CaCO_3后,棚膜对紫外光均有明显的屏蔽效果,对可见光的透光率也均有所提升,其中添加nano-TiO_2的棚膜的紫外光屏蔽效果以及对可见光的透光率均明显高于添加nano-CaCO_3的棚膜。

Effects of Nano-TiO2 and Nano-CaCO3 on Properties of EVAC Droplet Greenhouse Films

Nano-TiO2 or nano-CaCO3,anti-dropping agent Span 60 and other additives were mixed,the anti-dropping master-batch with ethylene-vinyl acetate plastic (EVAC) as the carrier was prepared by extruder and then the EVAC droplet greenhouse film was prepared by blow molding. The effects of nano-TiO2 or nano-CaCO3 contents on the tensile properties,anti-dropping property and light transmittance on the films were studied. The results show that the appropriate addition of nano-TiO2 or nano-CaCO3 can im-prove the tensile strength of the film. When the content of nano-CaCO3 in the masterbatch is 4 phr,the vertical and horizontal tensile strengths of the film are the largest,but when the content of nano-TiO2 in the masterbatch is 2 phr,the vertical and horizontal tensile strengths are highest. The addition of nano-TiO2 improves the anti-dropping property of the film slightly,while the nano-CaCO3 reduces the anti-dropping property. With the addition of nano-TiO2 or nano-CaCO3,the film has a significant shielding effect on the ultraviolet light,the visible light transmittance also is improved,the film added by nano-TiO2 has better ultraviolet shielding effect and the visible light transmittance than those added by nano-CaCO3.