玻纤毡增强聚丙烯复合材料的增容及力学性能

Compatibilization and Mechanical Properties of Glass Fiber Mat Reinforced Polypropylene Composites

通过玻璃纤维(GF)毡与双螺杆挤出相容剂改性聚丙烯(PP)膜的多层叠合,以熔融浸渍法制得PP基GF毡增强热塑性塑料(GMT)复合材料,研究了相容剂PP接枝马来酸酐(PP-g-MAH)和PP接枝丙烯酸(PP-g-AA)的用量(为PP基体质量的百分数)及其复配改性,以及相容剂改性PP基体分布和毡体种类对GMT力学性能的影响。结果表明,PPg-MAH可明显提高GMT的拉伸与弯曲性能,但降低了冲击性能;PP-g-AA可明显提高GMT的冲击性能,但不利于拉伸与弯曲性能的提高,只有当PP-g-AA用量超过5%后,拉伸性能才有所提升。在PP-g-MAH用量为3%的条件下,将其与不同用量的PP-g-AA进行复配改性没有对GMT力学性能产生协同作用。在各相容剂用量相近(3%~3.5%)的情况下,与相容剂复配改性GMT相比,以两层PP-g-AA改性PP为芯层、PP-g-MAH改性PP为上下表面层作为改性基体分布时,GMT拉伸与弯曲强度分别提高17%和27%、缺口冲击强度提高48%;而以两层PP-g-MAH改性PP为芯层、PP-g-AA改性PP为上下表面层作为改性基体分布时,在不损失强度与刚性的同时,缺口冲击强度提高了88%。采用连续GF毡的GMT力学性能比采用短切GF毡的GMT高,尤其是缺口冲击强度提高了89.6%。

Glass fiber(GF)mat reinforced thermoplastic(GMT)composites based on polypropylene(PP)were prepared bymelt impregnation method through multilayer stacking of GF mats and compatibilizer modified PP films extruded by twin screwextruder.The effects of compatibilizer PP-g-MAH and PP-g-AA contents(percentage of PP matrix mass)and their combination,compatibilizer modified PP matrix distribution and mat type on mechanical properties of GMT were investigated.The results showthat PP-g-MAH can increase the tensile and flexural properties of GMT obviously,but decreases the impact strength.For PP-g-AA,it can improve the impact strength significantly but can’t improve the tensile and flexural properties,only the content of PP-g-AAis above5%,the tensile properties are increased.When the content of PP-g-MAH is3%,the combination of it and PP-g-AA withdifferent contents does not produce synergistic effect on the mechanical properties of GMT.Compared with GMT modified by thecompatibilizer combination on the base of similar content(3%–3.5%)of each compatibilizer,for the matrix distribution design oftwo layers PP films modified by PP-g-AA as core layers and PP films modified by PP-g-MAH as the upper and lower surface layers,the tensile and flexural strength of the composites are increased by17%and27%respectively,while the notched impact strength isimproved by48%,on the other hand,for the distribution design of two layers PP films modified by PP-g-MAH as core layers and thePP matrix modified by PP-g-AA as upper and lower surface layers,the notched impact strength of GMT is improved by88%withoutthe loss of strength and rigidity.Moreover,the mechanical properties of GMT with continuous GF mat are higher than those of GMTwith short GF mat,especially the the notched impact strength is improved by89.6%.