MWCNTs-PVA复合材料的制备及性能研究

Study on Preparation and Properties of MWCNTs-PVA Composites

摘要:

聚乙烯醇（PVA）是一种可降解高分子材料，具有生物相容性和亲水性等优良特点，在涂料、纳米纤维、纺织、浆料、粘合剂及复合材料中具有非常广泛的应用。为了改善PVA的力学性能和耐热稳定性，利用淀粉基分散剂处理的具有较大长径比的多壁碳纳米管（MWCNTs） 制备了MWCNTs-PVA复合材料，并对其力学性能和热稳定性进行了测试。结果表明：当优化后的MWCNTs的添加量（质量分数）为0.50%时，MWCNTs-PVA复合材料具有较好的拉伸强度，最高可以达到129.2 MPa，与未加MWCNTs的PVA材料相比，其拉伸强度提高了33%、断裂伸长率为276%、热分解温度向更高温方向右移；当MWCNTs添加量为1%时，MWCNTs-PVA复合材料第二阶段的分解温度由288.5 ℃提高到295.3 ℃，第三阶段的分解温度由422.1 ℃提高到427.1 ℃，表明MWCNTs的加入有助于增强复合材料的热稳定性。因而，使用优化的MWCNTs制备新型复合材料，可以显著提高MWCNTs力学性能和热稳定性。

Abstract:

Polyvinyl alcohol （PVA） is a degradable polymer material with excellent characteristics such as biocompatibility and hydrophilicity. It has a very wide range of applications in coatings， nanofibers， textiles， sizing， adhesives and especially composite materials. To improve the mechanical properties and thermal stability of polyvinyl alcohol （PVA）， multi-walled carbon nanotubes （MWCNTs） with large aspect ratio treated by starch-based dispersant were prepared in this paper， and their mechanical properties and thermal stability were tested. The results show that when the optimized MWCNTs content is 0.50 wt.%， the MWCNTs-PVA composite has a good tensile strength， which can reach 129.2 MPa. Compared with PVA without MWCNTs， the tensile strength is increased by 33% and the elongation at break is 276%. In addition， compared with the PVA material without MWCNTs， the thermal decomposition of MWCNTs-PVA composite shifted to the right in the direction of higher temperature. When the addition of MWCNTs is 1 wt.%， the decomposition temperature of MWCNTs-PVA composites increases from 288.5 ℃ to 295.3 ℃ in the second stage， and from 422.1 ℃ to 427.1 ℃ in the third stage， which indicates that the addition of MWCNTs is helpful to enhance the thermal stability of the composites. Therefore， the mechanical properties and thermal stability of MWCNTs can be significantly improved by using optimized MWCNTs to prepare new composite materials.