双向拉伸聚对苯二甲酸乙二醇酯/聚己二酰间苯二胺的形态结构与阻隔及力学性能

Morphology, Barrier and Mechanical Properties of Biaxially Stretched Poly(ethylene terephthalate)/Poly(m-xylene adipamide)

以聚对苯二甲酸乙二醇酯(PET)和聚己二酰间苯二胺(MXD6)为原料,通过熔融共混和同步双向拉伸的方法制备了双向拉伸PET/MXD6复合材料。通过扫描电子显微镜、气体渗透试验、差示扫描量热仪及力学性能测试研究了双向拉伸PET/MXD6复合材料的形态结构及其对复合材料气体阻隔性能、力学性能及结晶性能的影响。研究结果表明,通过同步双向拉伸,使MXD6在PET基体中的分散相形态由零维球形变为高长径比的二维片状,这些形态使得双向拉伸复合材料的气体阻隔性能与力学性能大幅提高,其中质量分数20%的PET/MXD6复合薄膜材料在拉伸倍率为3×3时,较纯PET相比提升了2.3倍。与此同时,断裂伸长率与拉伸强度也大幅提高,最大增幅分别达到10.6倍和3.1倍。

Poly(ethylene terephthalate)(PET) and poly(m-xylene adipamide)(MXD6) were used as raw material to prepare PET/MXD6 composites by melt blending and simultaneous biaxially stretching. Scanning electron microscopy(SEM), gas permeation test, differential scanning calorimetry(DSC) and mechanical properties test were used to study the morphology structure of PET/MXD6 composites and their effects on the gas barrier, mechanical properties and crystallization properties. The results show that the morphology of the MXD6 dispersed phase in the PET matrix changes from zero-dimensional spherical shape to two-dimensional sheet shape with high aspect ratio by simultaneous biaxially stretching, which leads to a significant improvement in the gas barrier and mechanical properties of biaxial stretching composites, the 20% PET/MXD6 composite film material increased by 2.3 times compared with pure PET when the tensile ratio is 3×3. The elongation at break and tensile strength are also increased significantly, with the maximum increase of 10.6 times and 3.1 times, respectively.