橡胶基复合材料用高性能纤维的表面修饰及其粘合性能研究

发布时间：2018-07-23 12:23

【摘要】：伴随着高性能橡胶制品的需求量日益增大,高性能纤维骨架材料得到了快速的发展。芳纶纤维是目前高性能橡胶骨架材料的主要成员之一。相比传统的骨架材料,芳纶纤维具更优异的力学性能,耐热性,和化学稳定性等性能。目前已经实现在轮胎、输送带、和胶管等领域的应用。超高分子量聚乙烯纤维具有较高的拉伸强度,抗切割以及抗冲击性等突出的力学特性,良好的光稳定性和耐腐蚀性,在橡胶工业中也具有一定应用前景。但是由于具有较高的结晶度,表面光滑且化学惰性较强,这两种纤维与橡胶的界面粘合作用较差。多巴胺仿生修饰方法对基体表面性质没有依赖性,对环境没有污染,是一种简单而有效的新改性手段。它能够有效改善芳纶纤维和超高分子量聚乙烯纤维与橡胶基体的界面粘合性能,但昂贵的成本限制了这种纤维改性方法在工业中的应用。多巴胺超强粘附性的一个重要原因就是结构中含有酚羟基和氨基基团,针对这个观点我们选用了分别含有这两种基团的单体邻苯二酚和多胺对多巴胺进行有效替代,这两种单体的成本不足多巴胺的百分之一。单宁酸是一种植物多酚,由于富含邻苯二酚和连苯三酚结构,可以与金属离子发生配位反应在基体表面形成多酚-金属络合层。γ射线对纤维进行辐照改性使近年来一种较新颖的改性手段,这种手段不需要特定的引发剂或催化剂,对温度也没有特殊要求。受上述观点启发,本文探索了三种纤维表面修饰方法来改善纤维与橡胶的界面粘合性能。具体内容如下:(1)通过邻苯二酚/多胺的共沉积和硅烷偶联剂γ-缩水甘油醚氧丙基三甲氧基硅烷(GPTMS)的接枝改性对对位芳纶(PPTA)纤维进行了表面修饰。聚(邻苯二酚/多胺)(PCPA)在芳纶纤维表面沉积的最佳反应条件如下:邻苯二酚/四乙烯五胺(TEPA)组合,摩尔比为3:1,反应溶液的pH为9.5。探究了接枝反应温度以及单体的反应浓度对GPTMS的接枝率的影响。接枝引入的环氧基团可以参与橡胶硫化,有效提高了PPTA纤维/橡胶复合材料的界面粘合性能。相比多巴胺处理的方法,这种方法有较短的预沉积时间,相比多巴胺缩短了 1 h,同时将PPTA纤维与橡胶的界面粘合强度提升了 83.3%,甚至优于多巴胺方法处理的改性效果(67.5%)。除此之外,酚胺的成本不到多巴胺的1%。由于本实验方法具有可控,低成本,高效等优点,有在橡胶工业领域广泛应用的前景。(2)酚胺仿生修饰的改性方法已经证明能够有效改善芳纶纤维与橡胶基体的界面粘合性能,但是较长的PCPA预沉积时间限制了这种方法在橡胶工业的应用。分别采用紫外辐照和添加氧化剂的方法来加速邻苯二酚/多胺的氧化自聚合进程以及在芳纶纤维表面的沉积速率。在紫外辐照的条件下,PCPA在纤维表面的预沉积时间缩短到了 1h。之后,利用乙二醇二缩水甘油醚(EGDE)对PCPA修饰的芳纶纤维进行接枝改性引入环氧基团。利用抽出力测试探究了 EGDE浓度和接枝时间对芳纶纤维与橡胶基体的界面粘合强度的影响。相比未改性PPTA纤维,改性纤维与橡胶的界面抽出力最大提升了 85.6%。添加氧化剂的处理方式,使PCPA预沉积时间缩短到了 30 min。随后接枝了硅烷偶联剂双-(γ-三乙氧基硅基丙基)四硫化物(Si69),将芳纶纤维/橡胶复合材料的界面抽出力提升了 42%。(3)采用一种绿色环保而且有效的方法改善了芳纶纤维与橡胶基体的界面粘合性能。单宁酸(TA),一种天然多酚,可以短时间内与三价铁离子通过络合作用在纤维表面形成一个金属-多酚的粘附层。然后,在单宁酸/三价铁(TA/FeⅢ)修饰的芳纶纤维表面分别接枝了硅烷偶联剂Si69和GPTMS。通过在纤维表面引入高活性的环氧基团和多硫键,将芳纶纤维/橡胶复合材料的界面粘合强度分别提升了 73.6%和55.4%。相比我们之前采用的多巴胺仿生修饰的方法,这个方法具有成本低和反应时间短的优势,具有一定工业化应用前景。此外,这种利用植物多酚改性纤维的方法也符合绿色化学的需求。(4)采用伽马射线引发单体甲基丙烯酸缩水甘油酯(GMA)分别在PPTA纤维和UHMWPE纤维表面接枝聚合。选择的实验方案为共辐射接枝,具体操作是将纤维浸渍到氮气气氛条件下GMA的甲醇溶液中进行共辐射处理。研究了不同单体浓度对纤维表面接枝率的影响。纤维与橡胶基体的的界面粘合强度随单体浓度的增加而增大。当GMA浓度达到12 vol%的时候,PPTA纤维/橡胶复合材料和UHMWPE纤维/橡胶复合材料的界面抽出力分别提升了 130%和93.6%。
[Abstract]:With the increasing demand for high performance rubber products, high performance fiber skeleton materials have been developed rapidly. Aramid fiber is one of the main members of high performance rubber skeleton materials. Compared with traditional skeleton materials, aramid fiber has better mechanical properties, heat resistance, chemical stability and so on. Ultra high molecular weight polyethylene fiber has high tensile strength, anti cutting and impact resistance and other outstanding mechanical properties, good light stability and corrosion resistance. It has a certain application prospect in the rubber industry. But because of its high crystallinity, the surface is smooth and changed. The interfacial adhesion of the two fibers and rubber is poor. The dopamine biomimetic modification method has no dependence on the surface properties of the matrix and has no pollution to the environment. It is a simple and effective new means of modification. It can effectively improve the interfacial adhesion between the aramid fiber and the UHMWPE fiber and the rubber matrix. But the expensive cost limits the application of this fiber modification method in industry. One important reason for the super strong adhesion of dopamine is that the structure contains phenolic hydroxyl groups and amino groups. In this view we have selected the two groups of monomeric catechol and polyamines to replace the dopamine effectively, these two kinds of monomers. The cost of the body is less than one percent of the dopamine. Tannic acid is a kind of plant polyphenols. Due to the structure of catechol and polyphenols, it can react with metal ions to form a polyphenol metal complex layer on the surface of the matrix. For a specific initiator or catalyst, there is no special requirement for temperature. Inspired by the above viewpoint, three kinds of fiber surface modification methods have been explored to improve the interfacial adhesion of fiber and rubber. The specific contents are as follows: (1) co deposition of catechol / polyamine and silane coupling agent gamma glycidoxypropyl trimethoxysilicon The surface modification of the para aramid (PPTA) fibers by the grafting modification of alkane (GPTMS). The optimum reaction conditions for the deposition of poly (catechol / polyamine) (PCPA) on aramid fiber are as follows: the combination of catechol / four ethylene five amine (TEPA), the molar ratio of 3:1, and the pH of the reaction solution to 9.5. to explore the grafting reaction temperature and the reaction concentration of the monomer to GP The effect of the grafting ratio of TMS. The epoxy group introduced by the graft can participate in rubber vulcanization, effectively improving the interfacial adhesion of the PPTA fiber / rubber composites. Compared with the dopamine treatment method, the method has a shorter deposition time, 1 h shorter than dopamine, and the bonding strength of the PPTA fiber and rubber at the same time. 83.3%, and even better than dopamine treatment modified effect (67.5%). Besides, the 1%. of Phenolamine has the advantages of controllable, low cost and high efficiency. (2) the modification method of Phenolamine biomimetic modification has proved to be able to improve the aramid fiber effectively. The interfacial adhesion with the rubber matrix, but the longer PCPA predeposition time restricts the application of this method to the rubber industry. UV irradiation and the addition of oxidants are used to accelerate the process of the oxidation of catechol / polyamine and the deposition rate on the surface of aramid fiber. Under UV irradiation, PCPA is The predeposition time of the fiber surface was shortened to 1h., and ethylene glycol two glycidyl ether (EGDE) was used to graft the PCPA modified aramid fiber into the epoxy group. The effect of EGDE concentration and grafting time on the bonding strength of the boundary between the aramid fiber and the rubber matrix was investigated by the extraction force test. Compared to the unmodified PPTA fiber, the effect of the EGDE concentration and the grafting time were investigated. The interfacial pulling force of the modified fiber and rubber greatly enhanced the treatment of 85.6%. adding oxidant, shortened the PCPA pre deposition time to 30 min. and then grafted the silane coupling agent, double (gamma triethoxyl silicon propyl) four sulfide (Si69), and increased the interfacial pulling force of the aramid fiber / rubber compound to 42%. (3). A green and effective method improves the interfacial adhesion between the aramid fiber and the rubber matrix. Tannic acid (TA), a natural polyphenol, can form a metal polyphenols adhesion layer on the fiber surface in a short time with trivalent iron ions. Then, the surface of the tannic acid / trivalent iron (TA/Fe III) modified aramid fiber surface. The grafting of silane coupling agent Si69 and GPTMS. respectively by introducing highly active epoxy groups and polysulfide bonds on the surface of the fiber, the interfacial bonding strength of aramid fiber / rubber composites is increased by 73.6% and 55.4%., compared to the dopamine biomimetic modification that we used before. This method has low cost and short reaction time. In addition, the method of using plant polyphenols to modify fiber also meets the requirements of green chemistry. (4) graft copolymerization of PPTA fiber and UHMWPE fiber on the surface of GMA with gamma ray induced monomeric glycidyl methacrylate. Co radiation treatment was carried out in the methanol solution of GMA under nitrogen atmosphere. The effect of different monomer concentration on the grafting ratio of fiber surface was studied. The interfacial adhesion strength of fiber and rubber matrix increased with the increase of monomer concentration. When the concentration of GMA reached 12 vol%, PPTA fiber / rubber composite and UHMWPE The interfacial extraction force of fiber / rubber composites increased by 130% and 93.6%. respectively.
【学位授予单位】：北京化工大学
【学位级别】：博士
【学位授予年份】：2017
【分类号】：TQ342.72;TB33

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