【作者】 张驰；

【导师】 牟其伍；

【作者基本信息】 重庆大学 ， 材料物理与化学， 2006， 硕士

【摘要】 超高分子量聚乙烯(UHMWPE)纤维化学上不活泼,表面能低,表面缺乏极性基团,且超高模量聚乙烯纤维是高度对称的亚甲基结构,使得纤维具有很高的结晶度和取向度。这一方面保证其具有较高的力学强度,另一方面也使得纤维表面的化学惰性特别突出,集中表现在与树脂基体制成复合材料后,界面结合力很低。因此需对超高模量聚乙烯纤维改性。目前研究较多的采用等离子表面处理超高分子量聚乙烯纤维,采用空气等气体电离后产生的高能离子轰击纤维表面,使纤维表面产生过氧基团等一系列活泼基团,这些基团容易活化,使纤维与树脂间产生化学键接。从而增加粘接强度。但等离子处理过程中,由于仅仅在纤维表面产生活性基团,活性基团数量较少。且活性基团在空气中容易衰退,因此难以得到广泛的应用。采用表面接枝的方法,可以按照人为设计,在纤维的表面生成接枝共聚物层,这些接枝共聚物可以按照设计包含特定的官能团,但由于超高分子量聚乙烯的化学惰性,通过在液态溶液接枝聚合的方法中难以在表面引发接枝。本文主要采用等离子接枝聚合表面处理和等离子引发紫外光接枝聚合表面处理的方法在超高分子量聚乙烯纤维表面分别接枝苯乙烯和甲基丙烯酸。超高模量聚乙烯纤维经上述两种方法改性后浸润性能和粘接强度都得到的提高。经过普通等离子处理的纤维与乙二醇之间的接触角为75.3o,与环氧树脂间粘接强度为1.69Mpa。而采用等离子接枝聚合苯乙烯表面处理改性的高分子量聚乙烯纤维的接触角可以降低至24.60o,接枝甲级丙烯酸后单丝粘接强度可以达到2.14Mpa。等离子引发紫外光接枝苯乙烯聚合表面处理高分子量聚乙烯纤维的接触角可以降低至37.40o,接枝甲级丙烯酸单丝粘接强度可以达到2.26Mpa。采用经过改性处理后的纤维所制备的环氧树脂基复合材料的拉伸性能和层间剪切性能也得到大幅度的提升。等离子接枝聚合表面处理后复合材料的拉伸强度比等离子处理提高了37.5%,层间剪切强度提高了30.1%。等离子引发紫外光接枝聚合表面处理后复合材料拉伸强度比等离子处理提高了82%,层间剪切强度提高了92.9%。经过改性处理后,复合材料的拉伸破坏较少表现为脆性断裂,这说明纤维与基体之间粘接良好,基体可以传递和分散拉伸过程中的应力。同时红外光谱分析也表明,采用上述两种方法接枝改性的超高分子量聚乙烯表面都成功的接枝上了聚苯乙烯和聚甲基丙烯酸。更多还原

【Abstract】 The ultra high molecule weight polyethylene (UHMWPE) fiber is chemically inactive with none function on its surface. It lacks active radical on its surface. And ultra high molecule weight polyethylene fiber is highly symmetrical structure of methylene, which makes the fiber Possesses high crystalline and degree of orientation. On one hand, this ensure that it has relatively high intension in terms of mechanics; on the other hand, it makes the external chemical inertness of the fiber very obvious, which is mainly represented by the low interface binding force after the fiber is made into composite material. So it is necessary to modify the ultra high module polyethylene fiber.At present there is many uses of plasma surface treatment on ultra high molecular weight polyethylene fiber, after uses high energy ion bombardment surface of fiber which electrification by air plasma , it causes the fiber surface to have the oxygen groups and so on . these groups are easy to activate, it cause chemical bond between the textile fiber and the resin produce . Thus increase Adhesion intensity In plasma treatment processes, because it only has the active groups merely in the fiber surface, the active groups quantity are few. Also the active groups are easy to decline in the air, therefore It obtains the widespread application with difficulty.Uses the surface grafting method, it may defer to the artificial design, in the fiber surface production graft polymer level, these graft polymers may defer to the design to contain the specific functional group, but as a result of high macromolecular weight polyethylene chemistry inertia, through in liquid solution surface grafting polymerization method with difficulty in superficial initiation surface grafting.This article mainly uses the plasma grafting polymerization surface treatment and the plasma initiation grafting polymerization surface treatment method in the ultra high molecular weight polyethylene fiber surface distinction grafting styrene and the methyl acrylic acid. The wetability and the adhesion intensity are enhanced after the above two methods modification. After the ordinary plasma processing, the fiber contract angle is 75.3o, The adhesion intensity is 1.69Mpa. But uses the plasma grafting polymerization surface treatment modified macromolecular weight polyethylene fiber the contract angle is to be possible to reduce to 24.60o, the single filament adhesion intensity may 2.14Mpa. The plasma initiation grafting polymerization surface treatment更多还原