PVA/LDH-aCNTs杂化薄膜的制备及其性能研究

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

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。

Hybrid film based on layered double hydroxides(LDHs)and acidified carbon nanotubes(aCNTs)wassynthesized 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,andscanning electron microscopy.The microstructure and mechanical properties of the PVA/LDH-aCNTs hybrid film wereinvestigated.The mechanical tests suggested that the tensile strength of the PVA hybrid film containing3wt%LDHaCNTsreached a maximum value.Compared to pure PVA,the tensile strength of PVA hybrid film was increased by41%.The compatibility between aCNTs and PVA was effectively improved by LDHs,which enhanced the mechanicalproperties of the film.The water absorbency test showed that the water absorption of5wt%PVA/LDH-aCNTs hybridfilm declined by58%compared with the pure PVA(water absorption rate being649%).The hydrogen bonding formedbetween oxygenic functional groups on the LDH-aCNTs hybrid nanoparticles and hydroxyl in the chain of PVA,whichreduced the bare hydrophilic group and declined the water absorption.The mechanical properties and water resistanceof the PVA/LDH-aCNTs hybrid film were also improved,which could hopefully broaden its application domain.