酸处理凹凸棒黏土对PVA/APT纳米复合膜理化性能的影响

Influence of Acidification of APT on the Properties of PVA/APT Nanocomposite Films

在固体与液体质量比(简称固液比,下同)为1∶10时,将凹凸棒黏土(APT)分别采用体积分数1%盐酸、H2 SO4、H3 PO4、HClO4和H4 P2 O7溶液进行处理。以聚乙烯醇(PVA)和各种酸处理APT为原料,采用溶液-流延成膜法,制备了系列PVA/APT纳米复合膜。采用FTIR、SEM和XRD对PVA/APT纳米复合膜的结构进行了表征,测试了PVA/APT纳米复合膜的力学性能和耐水性能。结果表明,酸处理能溶出APT孔道中的杂质和碳酸盐,提高棒晶束的分散程度,因而APT可均匀分散在PVA基体中。与APT原土相比,酸处理APT明显改善了纳米复合膜的力学性能和耐水性能。其中,以HClO4处理APT时纳米复合膜的性能最优,拉伸强度及断裂延伸率分别提高了29.3%和74.9%,耐水性提高了32.2%。

Attapulgite（APT） was treated with 1% （volume fraction） HCl, H2SO4, H3PO4, HClO4 and H4P2O7 solution at a ratio of solid to liquid of 1：10. Subsequently, using film-casting method, a series of poly （vinyl alcohol）/attapulgite（PVA/APT） nanocomposite films were prepared from the raw materials of poly （ vinyl alcohol） and APT treated with different acids. The microstructures of tile nanocomposite films were characterized by means of FTIR, SEM and XRD, and the mechanical properties and waterresistance of the nanocomposite films were tested. The experimental results indicate that the method of acid treatment can increase the dispersity of APT by dissolving the impurities and carbonate in the pore canal, and then APT can be dispersed better in PVA matrix, which significantly improved the mechanical properties and water-resistance of the nanocomposite films. Compared with natural APT, when APT treated with 1% （ volume fraction） HClO4 was added, the nanocomposite film exhibited optimum performances： the tensile strength, elongation at break and water resistance of the nanocomposite films increased by 29.3% ,74.9% and 32.2% ,respectively.