导　　师： 王小萍

学科专业： 080502

授予学位： 硕士

作　　者： ;

机构地区： 华南理工大学

摘　　要： 据统计我国每年的报废轮胎差不多1亿条,如何利用这么大量的废轮胎是环境保护中十分重大的问题。废轮胎可以生产废胶粉,并副产大量的废轮胎纤维。为了同时回收利用废胶粉和废纤维,解决不饱和树脂固化后硬而脆、耐冲击性能差的问题。本课题首次提出并制备了不饱和聚酯//废胶粉//废纤维复合材料,利用不饱和聚酯作为基体和粘接剂,废纤维作为增强增韧材料,废胶粉作为增韧和填充材料,通过调整三者的比例,获得了具有优良综合性能的环保复合材料。 本文对所使用的废胶粉和废纤维的基本情况进行了表征。结果表明,所用的废胶粉的平均粒径为174.4μm;测试分析表明废胶粉的组成是橡胶等有机物为62.5wt/%,炭黑为26.3wt/%,无机填料为11.18wt/%;废胶粉中的橡胶组分为天然橡胶和顺丁橡胶。研究表明废纤维直径约为30μm左右,长径比约为100～150之间其主要成为尼龙6和尼龙66纤维。 本文用DMA技术来探讨了复合材料的固化和后固化工艺。确定135～150℃为复合材料的快速固化温区;发现在145℃固化时凝胶时间大概为17.8min,后固化条件为170℃×6h时,材料性能最佳。 用废胶粉增韧复合材料。TEM和光电子能谱测试结果表明,苯乙烯单体可以渗透到废胶粉颗粒中并交联;SEM、TEM测试表明苯乙烯单体预处理后的废胶粉在树脂中的分散比较均匀,废胶粉与树脂的界面变得模糊,两相界面结合良好;预处理时间为12h时复合材料的综合性能最佳。废胶粉量在15～20phr时,冲击强度由不加废胶粉时的13kJ//m2提高到20kJ//m2,提高了54/%,增韧效果明显,综合力学性能最佳。 对废纤维进行改性研究,发现废纤维经过四种改性剂改性后的复合材料的力学性能都得到了一定的提高,其中改性剂MF的改性效果最好,最佳用量为6～12phr。改性纤维在用量为120phr左右时有最佳综合性能,拉伸强度、弯曲强度和冲击强度分别为21.27MPa、50.45MPa和21.29kJ//m2,比没改性的分别提高了73.2/%、35.5/%和19.7/%,这说明废纤维对复合材料有增强增韧作用。红外光谱图和显微照片分析表明改性剂MF可以粘附到废纤维表面;DMA测试结果表明,改性剂MF的加入可提高废纤维跟树脂的相容性,增加复合材料的储能模量;接触角测试表明改性剂MF的加入有利于提高材料的疏水性;SEM测试表明,改性剂MF的加入增强了废纤维与树脂间粘结性,使得它们之间的结合更加牢固,这也是加入改性剂MF的材料力学性能大幅提高的主要原因。 对复合材料进行了热氧老化性能研究。测试分析表明:复合材料的热氧老化主要以交联反应为主;随着老化条件的苛刻度增加,交联程度越高,各组分间相容性下降。 在80℃热水老化后,复合材料的拉伸强度、弯曲模量和弯曲强度都大幅下降,而冲击强度略有上升。其原因可能是水的增塑作用、废纤维能在热水中水解以及不饱和聚酯与水形成氢键。 According to statistics, there are almost 100 million scrap tires every year in China. How to deal with so large number of waste tires is a very critical issue in environmental protection. Lots of waste fibers are by-product during making the waste rubber powder by waste tires. In order to simultaneously recycle waste rubber powder and fiber and solve shock resistant performance problems of the unsaturated resin after curing, the first time the unsaturated polyester // waste rubber powder // tires fiber composites were raised and prepared in this study. Using unsaturated polyester as matrix and adhesive, waste fiber as toughening and reinforcing materials and waste rubber as toughening and filled materials, the environmental composites with good overall performance were gained by adjusting the ratio of these three. In this paper, the waste rubber powder and waste fibers were characterized at first. The results showed that the average size of waste rubber powder is 174.4μm.Test analysis showed that the composition of the waste rubber powder is 62.5 wt/% organic matters, 26.3wt/% carbon black and 11.18wt/% inorganic filler. The rubber groups in the waste rubber powder are natural rubber and butadiene rubber. The studies showed that the diameter of the waste rubber powder is about 30μm and the aspect ratio of that is between 100 um and 150 um. Test results showed that the main compounds of waste fiber are nylon 6 and nylon 66 fibers. In this paper, DMA technique was used to study the curing and post-curing process of the composite. We found that the composites have fast curing speed when the temperature is 135 ~ 150℃; when the composites are cured at 145℃,the gel time is about 17.8min and post cured for 6h at 170℃, the composites have the best performance. We used waste rubber powder to toughen composite materials. TEM and X-ray photoelectron spectroscopy tests showed that styrene monomer can penetrate and cross-link in the powder particles. SEM and TEM tests showed that waste rubber powder pretreated by styrene monomer is more evenly distributed in the resin and the interface of waste rubber powder and resin has become blurred which indicating a good combination of the two-phase. The composite has the best performance when pretreatment time is12h. When the amount of waste rubber powder is15 ~ 20phr, relative to the composites without waste rubber powder, the impact strength raised from 13kJ//m2 to 20kJ//m2, increased by 54/%, the toughening effect is obvious and the mechanical properties is best. The mechanical properties of composite have been improved to some degree using different four modifiers on the modification of waste fibers. MF has the best modification effect and the optimal dosage is 6~12phr. When the dosage of modified waste fiber is 120phr, the tensile strength, flexural strength and impact strength of the composites are 21.27MPa, 50.45MPa and 21.29kJ//m2respectively and increased by 73.2/%, 35.5/% and 19.7/% than those without modification. These indicated that waste fibers can enhance the toughness and strength of the composites. IR and microscopic photographs showed the modifier MF can adhere to the surface of waste fiber. DMA test results showed that the modifier MF can enhance the compatibility of waste fibers and the resin and increase the storage modulus of composite. The contact angle test showed that the addition of MF modifier helps to improve the hydrophobic performance. The SEM showed that the addition of MF modifier increases adhesion between fiber and resin, making them combining solidly. And this is the main reason of the mechanical properties increas with adding modifier MF. The heat oxygen aging property of composite was studied. The results showed that the thermal aging of composite base mainly on cross-linking reaction. When the aging conditions are harsher, the degree of crosslink-king is higher and the compatibility among the various components decreased. When the composite were aging at 80℃hot water, tensile strength, flexural modulus and flexural strength were significantly decreased and the impact strength was increased slightly. The significant reasons may be water plasticization, hydrolysis of waste fiber in hot water and formation of hydrogen bonds of unsaturated polyester and water.

关 键 词： 不饱和聚酯 废胶粉 废纤维 固化 表面改性

分 类 号： [TB332]

领　　域： [一般工业技术]