【作者】 吴比；

【导师】 刘江龙；

【作者基本信息】 重庆大学 ， 材料加工工程， 2004， 硕士

【摘要】 废旧塑料的循环利用有利于节约资源和能源、减少环境污染。如果对每年350万吨可回收塑料包装材料加以回收利用,将会节约原油约1 225万吨,节约能源约210 000 000GJ相当于标煤为750万吨,同时,将减少废气排放700万立方米,减少污水排放56万立方米,还减少了大量的废渣和噪音。和废旧塑料的物理循环利用相比,现普遍使用的废旧塑料处理方式焚烧对环境的影响是巨大的。每燃烧1000kg聚乙烯会产生123.41kg多环芳烃。如果对每年350万吨(假设均为PE)废塑料进行焚烧,将会产生43.2万吨多环芳烃。同时废塑料在焚烧过程中会产生大量二恶英类化合物和硝基多环芳烃化合物。这些物质对包括鱼类、鸟类和哺乳动物在内的许多生物具有相当强的致癌、致畸和致基因突变作用。但由于单纯的废旧塑料再生料性能不高,限制了废旧塑料的应用,从而影响了废旧塑料的回收率。纤维增强废旧塑料基复合材料大大改善了废旧塑料的力学性能,拓展了废旧塑料的应用范围。鉴于纤维增强复合材料要求基体要有一定的韧性,首先研究了废旧PE和PP基体的共混增韧,获得在强度降低不大的情况下,增韧效果最好的共混组分的最佳共混比。HDPE/LLDPE的最佳共混比为40/60~20/80;PP/HDPE的为80/20左右;PP/LDPE的为80/20~60/40。然后着重研究了增强纤维的低温等离子体表面处理对增强纤维与基体间界面剪切强度的影响。证明了纤维的等离子体处理对纤维与基体的界面结合的提高作用;分析了纤维的等离子体处理增强界面结合的作用机理:一为提高了纤维表面的可浸润性,二为对纤维表面的刻蚀作用,增强了纤维的比表面积,同时增强了纤维与基体界面间的机械啮合作用;并得出了在相同处理参数(功率、真空度和工作气体)下等离子体处理时间为1~2分钟。最后研究了空间短纤维杂乱增强废旧塑料基复合材料的拉伸、冲击、弯曲等力学性能;分析了影响纤维增强废旧塑料基复合材料力学性能的因素;得出了空间短纤维杂乱增强废旧塑料基复合材料的综合力学性能大幅度提高的结论;并给出了空间短纤维杂乱增强废旧塑料基复合材料的制作工艺。更多还原

【Abstract】 Reuse of the waste plastic is propitious for saving of resources and decrease of pollution. With taking advantage of the recyclable plastic of annual 3.5 million ton to reuse, we will save crude oil 12.25 million ton, and save energy 210 million GJ (equal to 7.5 million ton coal). At the same time, 12.25 million ton waste gas and 560 thousand stere waste water and a lot of waste residue and noises will be evitable. Contrast to the physical recycle of waste plastic, the impact of setting on fire which is one of the most popular way to reuse now is great. Burning 1000 kg polythene will bring 123.41 kg mutiloop hydrocarbon. That is to say, annual 3.5 million ton waste plastic burned will bring 432 thousand ton mutiloop hydrocarbon. At the same time, with the burning of waste plastic, a large number of substance such as nitryl mutiloop hydrocarbon will be produced which will make the fish, the bird and other mammal have cancer and gene mutation.Due to the pure properties of waste plastic, its application is limited, and its recovery is influenced too. The composite that is based on fiber-reinforced waste plastic increases the mechanical properties of waste plastic and expand its application range.As the fiber-reinforced composite must has good ductility, first of all the mixing reinforcement of waste PE and PP were studied. The optimum mixture ratio was acquired with a little decrease of strength. The optimum mixture ratio of HDPE/LLDPE is 40/60~20/80, for PP/HDPE it is about 80/20, for PP/LDPE it is 80/20~60/40.Then the influence of low-temperature plasma surface treatment on interface shearing strength between reinforcing fiber and matrix was investigated. The stronger combination of fiber and matrix after plasma treatment was discovered. The mechanism of reinforcement of interface combination with plasma treatment was developed as follows: By means of plasma treatment, the wettability of fiber’s surface was increased, specific area of fiber was enhanced owing to the etching process, the meshing engagement between fiber and matrix was enhanced. With the same parameter( power, vacuum degree, processing gas), the optimum time of plasma treatment is 1~2 minutes. In the end, the mechanical properties of waste based composite treated by short fiber space random process was investigated, the comprehensive mechanical property of this kind of composite appeared much better. The manufacturing technology of waste plastic based composite treated by short fiber space random process was presented.更多还原