Jan Rahim, May Peter, Bell Alan P, Habib Amir, Khan Umar, Coleman Jonathan N
School of Chemical and Materials Engineering, National University of Sciences and Technology, H-12 Campus, Islamabad, Pakistan.
Nanoscale. 2014 May 7;6(9):4889-95. doi: 10.1039/c3nr06711d.
We have used liquid exfoliation of hexagonal Boron-Nitride (BN) to prepare composites of BN nanosheets of three different sizes in polyvinylchloride matrices. These composites show low levels of reinforcement, consistent with poor alignment of the nanosheets as-described by a modified version of Halpin-Tsai theory. However, drawing of the composites to 300% strain results in a considerable increase in mechanical properties with the maximum composite modulus and strength both ∼×3 higher than that of the pristine polymer. In addition, the rate of increase of modulus with BN volume fraction was up to 3-fold larger than for the unstrained composites. This is higher than can be explained by drawing-induced alignment using Halpin-Tsai theory. However, the data was consistent with a combination of alignment and strain-induced de-aggregation of BN multilayers.
我们采用六方氮化硼（BN）的液相剥离法，在聚氯乙烯基体中制备了三种不同尺寸的BN纳米片复合材料。这些复合材料显示出较低的增强水平，这与经修正的Halpin-Tsai理论所描述的纳米片排列不佳相一致。然而，将复合材料拉伸至300%应变会导致机械性能显著提高，复合材料的最大模量和强度均比原始聚合物高出约3倍。此外，模量随BN体积分数的增加速率比未拉伸的复合材料高出3倍。这比用Halpin-Tsai理论通过拉伸诱导排列所能解释的要高。然而，数据与BN多层的排列和应变诱导解聚的组合是一致的。
