PVA/LDH-aCNTs杂化薄膜的制备及其性能研究

采用恒定p H共沉淀法合成了层状双羟基氢氧化物(LDHs)和酸化碳纳米管(aCNTs)杂化材料,并将其作为填料应用到聚乙烯醇(PVA)薄膜中制备了PVA杂化薄膜。采用X射线衍射仪、拉曼光谱仪、扫描电子显微镜等对合成的LDH-aCNTs杂化材料进行了表征,并对PVA杂化薄膜进行了微观结构和力学性能测试。力学性能测试结果表明:当LDH-aCNTs的添加质量分数为3%时,PVA杂化薄膜的拉伸强度达到最大值,相比于纯PVA,拉伸强度约提高了41%。LDHs的存在有效地改善了aCNTs和PVA之间的相容性,使得PVA/LDH-aCNTs杂化薄膜具有较优异的力学性能。吸水性能测试结果表明:相比于纯PVA(吸水率为649%),添加质量分数为5%的PVA/LDH-aCNTs杂化薄膜的吸水率约下降了58%。LDH-aCNTs杂化纳米粒子中的含氧官能团能与PVA链中的羟基形成氢键,使裸露的亲水基团减少,吸水率下降。PVA/LDH-aCNTs杂化薄膜的力学性能和耐水性能的提高,有望拓宽PVA基复合薄膜的应用范围。

Preparation and Performance Study of PVA/LDH-aCNTs Hybrid Film

Hybrid film based on layered double hydroxides (LDHs) and acidified carbon nanotubes (aCNTs) was synthesized by constant pH coprecipitation method and was used as the novel nanofiller for poly(vinyl alcohol) (PVA) films. The obtained LDH-aCNTs hybrid materials were characterized by X-ray diffraction, Raman spectroscopy, and scanning electron microscopy. The microstructure and mechanical properties of the PVA/LDH-aCNTs hybrid film were investigated. The mechanical tests suggested that the tensile strength of the PVA hybrid film containing 3 wt % LDH-aCNTs reached a maximum value. Compared to pure PVA, the tensile strength of PVA hybrid film was increased by 41%. The compatibility between aCNTs and PVA was effectively improved by LDHs, which enhanced the mechanical properties of the film. The water absorbency test showed that the water absorption of 5 wt % PVA/LDH-aCNTs hybrid film declined by 58% compared with the pure PVA (water absorption rate being 649%). The hydrogen bonding formed between oxygenic functional groups on the LDH-aCNTs hybrid nanoparticles and hydroxyl in the chain of PVA, which reduced the bare hydrophilic group and declined the water absorption. The mechanical properties and water resistance of the PVA/LDH-aCNTs hybrid film were also improved, which could hopefully broaden its application domain.