PTW增强POM/TPU复合材料的制备及性能研究

摘要

Reinforced thermoplastic polyurethane elastomer (TPU )/polyoxymethylene (POM ) composites with potassium hexatitanate whisker (PTW)were prepared by a melt mixing method. Effect of PTW content on mechanical properties of TPU/POM composites was studied,and impact fracture morphologies of the composites were investigated by scanning electron microscopy.The results indicated that the impact toughness of POM was significantly improved by the addition of TPU.The notch impact strength of the composites increased by a factor of 2 .5 times compared with that of pure POM when 10 wt % TPU was incorporated.Nevertheless,the tensile and flexural strength showed a decrease in the presence of TPU. Mechanical properties of the composites at TPU/POM weight ratio of 10/90 could be significantly improved by the introduction of PTW.With the addition of 15 wt % PTW,the composites achieved optimum mechanical properties,in which the tensile strength,tensile modulus,elongation at break,flexural strength, flexural modulus,and notched impact strength reached 35.91 MPa,248.32 MPa,24.17 %, 144.94 MPa,12.26 GPa,and 112.1 kJ/m2 ,respectively.Compared with those of TPU/POM composite,the tensile modulus,flexural modulus and notched impact strength of the POM/TPU/PTW composite increased by 14.7 %,54.2 %and 9.2 %,respectively.%以钛酸钾晶须(PTW)为增强体,采用熔融共混和注射成型法,制备了聚甲醛(POM)/热塑性聚氨酯弹性体(TPU)/PTW复合材料.研究了PTW含量对POM/TPU复合材料力学性能的影响,并借助扫描电子显微镜(SEM)分析了冲击断面形貌.结果表明,TPU的加入有效改善了纯POM的韧性,当TPU含量为10%(质量分数,下同)时,缺口冲击强度是纯POM的2.5倍,但拉伸强度和弯曲强度有所下降;PTW的加入对POM/TPU有较好的增强效果,当PTW含量为15%时,复合材料的拉伸强度、拉伸模量、断裂伸长率、弯曲强度、弯曲模量、缺口冲击强度分别为35.91 MPa、24.17%、144.94 MPa、12.26 GPa、112.1 kJ/m2,拉伸模量、弯曲模量、缺口冲击强度与POM/TPU相比分别提高了14.7%、54.2%和9.2%,综合力学性能达到最佳.