碳系填料填充天然橡胶复合材料的设计、制备与性能研究
发布时间：2018-07-23 11:47
【摘要】：橡胶制品如汽车轮胎等的失效主要是由于裂纹的引发和扩展导致的。从材料的角度来看,橡胶和填料是影响橡胶复合材料裂纹引发和扩展的重要因素。本课题以天然橡胶(NR)为基体,重点探究了不同形状系数的碳系填料对NR在准静态条件下的裂纹引发、扩展,以及动态条件下的裂纹扩展性能的影响,并且分析了两者之间的关联性及其失效机理。填料主要包括球形炭黑(CB)、纤维状碳纳米管(CNTs)、片状氧化石墨烯(GO)。采用J-积分测试表征了准静态条件下的抗裂纹引发和扩展性能。J-积分测试得到临界J-积分JIC和撕裂模量TR等参数。JIC表征材料的抗准静态裂纹引发性能,TR表征材料的抗准静态裂纹扩展性能。采用动态疲劳测试研究了材料的抗动态裂纹扩展性能。主要内容包括以下四个部分:(1)研究了具有不同表面特性的CB和SiO_2杂化填料网络对NR复合材料的抗准静态和动态裂纹扩展性能的影响。结果表明,随SiO_2/CB质量比的增加(SiO_2与CB的填料总量为5O份),JIC和TR均逐渐增加,表明抗准静态裂纹引发和扩展能力得到提高。恒定应变下的动态疲劳测试表明,随SiO_2/CB质量比的增加,复合材料的动态裂纹扩展速率降低,疲劳寿命增加,这主要是由于恒定应变下的应变能密度随Si02/CB质量比的增加而降低。恒定应变下的动态疲劳的结果与准静态条件下的TR、JIC和应变能密度等参数的结果一致。因此,准静态条件下的复合材料的TR、JIC和应变能密度等参数可以用来预测恒定应变下的动态疲劳性能。(2)研究了纤维状CNTs和球形CB杂化填料网络对NR复合材料的准静态和动态裂纹扩展行为的影响。采用1份CNTs非等量替代3份CB的方式制备了具有相近硬度的CNTs/CB/NR复合材料。结果表明,CNTs和CB并用会对材料的抗准静态和动态裂纹扩展性能产生协同效应。填充3份CNTs的复合材料表现出最优异的抗疲劳性能。重点讨论了准静态和动态失效的协同机理和控制因素,例如CNTs的分散状态,杂化填料网络,应变诱导结晶,应变能密度以及粘弹性滞后损耗等因素。填充5份CNTs的NR表现出最弱的抗疲劳性能,原因是动态疲劳过程中的严重的滞后生热降低了材料的抗疲劳性能。(3)研究了片状GO对NR复合材料的抗准静态和动态裂纹扩展性能的影响。通过胶乳共絮凝工艺制备了 GO增强的NR复合材料。胶乳共絮凝实现了 GO片层的完全剥离和在橡胶基体中的均匀分散。结果表明,随GO含量的增加,GO/NR复合材料的力学性能、抗准静态裂纹引发和扩展能力都明显提高。GO具有比其它的传统填料更高的补强效率。恒定应变条件下,加入1份GO的NR复合材料具有最强的抗疲劳裂纹扩展性能。填充3份和5份GO的复合材料的抗疲劳性能较弱,主要原因是它们具有较高的滞后损耗和应变能密度。(4)对比研究了不同形状系数的碳系填料对NR裂纹扩展行为的影响,包括球形CB、纤维状CNTs以及片层GO。通过机械共混法或胶乳共絮凝法制备了具有相等硬度的填料均匀分散的复合材料。结果表明,填充25份CB,3份CNTs和4份GO的复合材料具有相等的邵A硬度(硬度均为52)。填充25份CB的NR表现出最佳的抗准静态裂纹引发和扩展性能以及抗疲劳性能。为了探究复合材料的失效机理,采用数字图像相关技术分析了裂纹尖端应变场的分布及应变放大效应。裂纹尖端应变场分布表明,填充25份CB的NR表现出最高的应变放大效应和放大面积,这些都将有助于耗散掉局部输入的能量,从而提高抗裂纹扩展性能。填料不仅能够提高橡胶材料的抗裂纹扩展性能,也可以提高材料的导电性能。导电橡胶制品是功能化橡胶材料的一个非常重要的研究领域。如上所述,GO在提高橡胶材料抗疲劳性能方面的能力有限,而它的还原产物即还原氧化石墨烯(RGO)却可以赋予橡胶材料优异的导电性能。本课题分别采用GO “先还原”和“后还原”的方式,制备了导电石墨烯/NR复合材料,并且分别探究了它们在应变敏感和溶剂敏感等领域的应用。具体包括以下两个部分:(1)采用明胶(Gel)作为界面稳定剂和助还原剂,水合肼(HAA)作为主还原剂,制备得到了 Gel-HHA-RGO水分散液,避免了 GO在还原过程中的不可逆团聚。Gel-HHA-RGO片层在碱性环境中表现出优异的胶体分散性和稳定性。通过水相溶液铸膜法制备了具有结构规整的石墨烯隔离网络的Gel-HHA-RGO/NR复合材料。随RGO含量的增加,复合材料的拉伸模量和动态储能模量提高了若干数量级。同时,RGO隔离网络降低了材料的导电阈渗值(0.21 vol%),提高了材料的电导率。应变敏感性测试表明,具有隔离网络结构的RGO/NR复合材料表现出优异的应变敏感性和重复性,可作为检测人体关节循环运动的传感器。(2)吸附到RGO上的界面改性剂会降低RGO的导电性能。通过将GO水分散液与NR胶乳混合,水相溶液铸模以及原位氢碘酸(HI)还原等一系列简单工艺,制备出具有三维连续石墨烯隔离网络的HI-RGO/NR复合材料,避免了表面改性剂的使用,同时简化了制备工艺。HI-RGO/NR表现出较低的导电阈渗值(0.31 vol%)和较高的电导率。当填充5.00 vol%的RGO时,材料的电导率高达49.3 S/m。当把HI-RGO/NR置于有机溶剂中时,NR基体会发生溶胀。通过检测电阻随时间的变化,我们研究了材料的溶剂敏感性能。HI-RGO/NR对有机溶剂表现出非常敏感的刺激响应,并且对不同的有机溶剂表现出不同的敏感响应。由于溶剂挥发之后连续RGO网络的重新构筑,该复合材料表现出优异的溶剂敏感重复性。
[Abstract]:The failure of rubber products, such as automobile tires, is mainly due to the initiation and expansion of cracks. From the point of view of material, rubber and filler is an important factor affecting the crack initiation and expansion of rubber composites. This topic is based on natural rubber (NR) as the matrix, focusing on the quasi static strip of NR in the carbon system with different shape coefficients. The effect of crack initiation, expansion and crack propagation under dynamic conditions, and the correlation and failure mechanism between the two are analyzed. The filler mainly includes spherical carbon black (CB), fibrous carbon nanotube (CNTs), and flaky graphene oxide (GO). The J- integral test is used to characterize the crack initiation and expansion under quasi-static conditions. The spreading performance.J- integral test obtains the critical J- integral JIC and the tearing modulus TR to characterize the anti quasi-static crack initiation properties, and TR characterizing the quasi static crack propagation properties. Dynamic fatigue testing is used to study the dynamic crack propagation properties of the material. The main contents include the following four parts: (1) the study has not been done. The effect of CB and SiO_2 hybrid packing network with the same surface properties on the quasi static and dynamic crack propagation properties of NR composites shows that JIC and TR increase gradually with the increase of the mass ratio of SiO_2/CB (the total amount of SiO_2 and CB is 5O), indicating that the ability to induce and expand the quasi static crack initiation and expansion. The fatigue test shows that with the increase of the mass ratio of SiO_2/CB, the dynamic crack propagation rate of the composite decreases and the fatigue life increases, which is mainly due to the decrease of the strain energy density under the constant strain with the increase of the mass ratio of Si02/CB. The results of dynamic fatigue under constant strain and the parameters of TR, JIC and strain energy density under quasi static condition The results are consistent. Therefore, the parameters such as TR, JIC and strain energy density in quasi-static composite materials can be used to predict the dynamic fatigue performance under constant strain. (2) the effect of fiber like CNTs and spherical CB hybrid packing network on the quasi static and dynamic crack propagation behavior of NR composites is studied. 1 CNTs non equal quantities are used instead of 3. The CNTs/CB/NR composites with similar hardness are prepared by CB. The results show that CNTs and CB can produce synergistic effects on the quasi static and dynamic crack propagation properties of the materials. The composite materials filled with 3 portions of CNTs exhibit the most excellent fatigue resistance. The synergistic mechanism and control of quasi static and dynamic failure are discussed. Factors such as the dispersion state of CNTs, hybrid packing network, strain induced crystallization, strain energy density and viscoelastic hysteresis loss. The NR filled with 5 parts CNTs shows the weakest anti fatigue properties, the reason is that the severe hysteresis heat in the dynamic fatigue process reduces the fatigue resistance of the material. (3) the study of the sheet GO to NR composite GO reinforced NR composites were prepared by the latex co flocculation process. The total peeling of the GO lamellae and the uniform dispersion in the rubber matrix were realized by latex flocculation process. The results showed that the mechanical properties of the GO/NR composite material with the increase of the content of GO, the resistance to quasi-static crack initiation and the resistance to quasi-static cracks were caused by the increase of the content of the GO/NR. The expansion ability obviously improves the reinforcing efficiency of.GO than other traditional fillers. Under constant strain conditions, 1 GO NR composites have the strongest fatigue crack propagation properties. The fatigue resistance of the composites filled with 3 and 5 copies of GO is weak, mainly due to their high hysteresis loss and strain energy density. Degree. (4) the effects of carbon fillers with different shape coefficients on the crack propagation behavior of NR were investigated, including spherical CB, fibrous CNTs and lamellar GO. by mechanical blending or latex co flocculation. The results showed that 25 CB, 3 CNTs and 4 GO composites were filled. Equal shore A hardness (hardness is 52). NR with 25 portions of CB shows the best anti static crack initiation and propagation properties and fatigue resistance. In order to explore the failure mechanism of the composite material, the distribution of strain field and strain amplification effect at the crack tip are analyzed by digital image correlation technique. The strain field distribution table at the crack tip is analyzed. It is clear that the filling of 25 CB NR shows the highest strain amplification effect and enlargement area, which will help to dissipate the local input energy and improve the crack propagation resistance. The filler can not only improve the crack growth resistance of the rubber material, but also improve the conductive properties of the material. The conductive rubber product is a functional rubber material. GO is a very important field of research. As mentioned above, the ability to improve the fatigue resistance of rubber materials is limited, and its reduction product, the reduction of graphene oxide (RGO), can give the rubber material excellent electrical conductivity. This topic has been prepared by GO "first reduction" and "after reduction", respectively, to prepare the tourmaline. The application of the /NR composites in strain sensitivity and solvent sensitivity are investigated. The following two parts are included: (1) using gelatin (Gel) as an interface stabilizer and reducing agent, hydrazine (HAA) as the main reducing agent, the Gel-HHA-RGO water dispersions are prepared to avoid the inability of GO in the process of reduction. The reverse reunion.Gel-HHA-RGO layer shows excellent colloidal dispersion and stability in the alkaline environment. Gel-HHA-RGO/NR composites with structured graphene isolation network are prepared by aqueous solution casting film method. With the increase of RGO content, the tensile modulus and dynamic energy storage modulus of the composite are increased by a number of orders of magnitude. The RGO isolation network reduces the conductivity of the material (0.21 vol%) and improves the conductivity of the material. The strain sensitivity test shows that the RGO/NR composite with isolated network structure shows excellent strain sensitivity and repeatability, and can be used as a sensor for detecting the movement of human joints. (2) the interfacial modifier adsorbed on RGO The conductivity of RGO can be reduced. By mixing GO water dispersions with NR latex, water phase solution casting and in situ hydroiodic acid (HI) reduction, a series of HI-RGO/NR composites with three dimensional continuous graphene isolation network are prepared, avoiding the use of surface modifier and simplifying the preparation process.HI-RGO/NR. Low conductivity threshold (0.31 vol%) and higher conductivity. When filled with 5 vol% RGO, the conductivity of the material is up to 49.3 S/m.. When HI-RGO/NR is placed in the organic solvent, the NR matrix will dissolve. By detecting the change of resistance with time, we have studied the solubility of the solution sensitivity of the material.HI-RGO/NR to the organic solvent. Sensitive response and sensitive response to different organic solvents. The composite exhibits excellent solvent sensitivity repeatability due to the restructure of continuous RGO networks after solvent volatilization.
【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】：TB332
本文编号：2139313
[Abstract]:The failure of rubber products, such as automobile tires, is mainly due to the initiation and expansion of cracks. From the point of view of material, rubber and filler is an important factor affecting the crack initiation and expansion of rubber composites. This topic is based on natural rubber (NR) as the matrix, focusing on the quasi static strip of NR in the carbon system with different shape coefficients. The effect of crack initiation, expansion and crack propagation under dynamic conditions, and the correlation and failure mechanism between the two are analyzed. The filler mainly includes spherical carbon black (CB), fibrous carbon nanotube (CNTs), and flaky graphene oxide (GO). The J- integral test is used to characterize the crack initiation and expansion under quasi-static conditions. The spreading performance.J- integral test obtains the critical J- integral JIC and the tearing modulus TR to characterize the anti quasi-static crack initiation properties, and TR characterizing the quasi static crack propagation properties. Dynamic fatigue testing is used to study the dynamic crack propagation properties of the material. The main contents include the following four parts: (1) the study has not been done. The effect of CB and SiO_2 hybrid packing network with the same surface properties on the quasi static and dynamic crack propagation properties of NR composites shows that JIC and TR increase gradually with the increase of the mass ratio of SiO_2/CB (the total amount of SiO_2 and CB is 5O), indicating that the ability to induce and expand the quasi static crack initiation and expansion. The fatigue test shows that with the increase of the mass ratio of SiO_2/CB, the dynamic crack propagation rate of the composite decreases and the fatigue life increases, which is mainly due to the decrease of the strain energy density under the constant strain with the increase of the mass ratio of Si02/CB. The results of dynamic fatigue under constant strain and the parameters of TR, JIC and strain energy density under quasi static condition The results are consistent. Therefore, the parameters such as TR, JIC and strain energy density in quasi-static composite materials can be used to predict the dynamic fatigue performance under constant strain. (2) the effect of fiber like CNTs and spherical CB hybrid packing network on the quasi static and dynamic crack propagation behavior of NR composites is studied. 1 CNTs non equal quantities are used instead of 3. The CNTs/CB/NR composites with similar hardness are prepared by CB. The results show that CNTs and CB can produce synergistic effects on the quasi static and dynamic crack propagation properties of the materials. The composite materials filled with 3 portions of CNTs exhibit the most excellent fatigue resistance. The synergistic mechanism and control of quasi static and dynamic failure are discussed. Factors such as the dispersion state of CNTs, hybrid packing network, strain induced crystallization, strain energy density and viscoelastic hysteresis loss. The NR filled with 5 parts CNTs shows the weakest anti fatigue properties, the reason is that the severe hysteresis heat in the dynamic fatigue process reduces the fatigue resistance of the material. (3) the study of the sheet GO to NR composite GO reinforced NR composites were prepared by the latex co flocculation process. The total peeling of the GO lamellae and the uniform dispersion in the rubber matrix were realized by latex flocculation process. The results showed that the mechanical properties of the GO/NR composite material with the increase of the content of GO, the resistance to quasi-static crack initiation and the resistance to quasi-static cracks were caused by the increase of the content of the GO/NR. The expansion ability obviously improves the reinforcing efficiency of.GO than other traditional fillers. Under constant strain conditions, 1 GO NR composites have the strongest fatigue crack propagation properties. The fatigue resistance of the composites filled with 3 and 5 copies of GO is weak, mainly due to their high hysteresis loss and strain energy density. Degree. (4) the effects of carbon fillers with different shape coefficients on the crack propagation behavior of NR were investigated, including spherical CB, fibrous CNTs and lamellar GO. by mechanical blending or latex co flocculation. The results showed that 25 CB, 3 CNTs and 4 GO composites were filled. Equal shore A hardness (hardness is 52). NR with 25 portions of CB shows the best anti static crack initiation and propagation properties and fatigue resistance. In order to explore the failure mechanism of the composite material, the distribution of strain field and strain amplification effect at the crack tip are analyzed by digital image correlation technique. The strain field distribution table at the crack tip is analyzed. It is clear that the filling of 25 CB NR shows the highest strain amplification effect and enlargement area, which will help to dissipate the local input energy and improve the crack propagation resistance. The filler can not only improve the crack growth resistance of the rubber material, but also improve the conductive properties of the material. The conductive rubber product is a functional rubber material. GO is a very important field of research. As mentioned above, the ability to improve the fatigue resistance of rubber materials is limited, and its reduction product, the reduction of graphene oxide (RGO), can give the rubber material excellent electrical conductivity. This topic has been prepared by GO "first reduction" and "after reduction", respectively, to prepare the tourmaline. The application of the /NR composites in strain sensitivity and solvent sensitivity are investigated. The following two parts are included: (1) using gelatin (Gel) as an interface stabilizer and reducing agent, hydrazine (HAA) as the main reducing agent, the Gel-HHA-RGO water dispersions are prepared to avoid the inability of GO in the process of reduction. The reverse reunion.Gel-HHA-RGO layer shows excellent colloidal dispersion and stability in the alkaline environment. Gel-HHA-RGO/NR composites with structured graphene isolation network are prepared by aqueous solution casting film method. With the increase of RGO content, the tensile modulus and dynamic energy storage modulus of the composite are increased by a number of orders of magnitude. The RGO isolation network reduces the conductivity of the material (0.21 vol%) and improves the conductivity of the material. The strain sensitivity test shows that the RGO/NR composite with isolated network structure shows excellent strain sensitivity and repeatability, and can be used as a sensor for detecting the movement of human joints. (2) the interfacial modifier adsorbed on RGO The conductivity of RGO can be reduced. By mixing GO water dispersions with NR latex, water phase solution casting and in situ hydroiodic acid (HI) reduction, a series of HI-RGO/NR composites with three dimensional continuous graphene isolation network are prepared, avoiding the use of surface modifier and simplifying the preparation process.HI-RGO/NR. Low conductivity threshold (0.31 vol%) and higher conductivity. When filled with 5 vol% RGO, the conductivity of the material is up to 49.3 S/m.. When HI-RGO/NR is placed in the organic solvent, the NR matrix will dissolve. By detecting the change of resistance with time, we have studied the solubility of the solution sensitivity of the material.HI-RGO/NR to the organic solvent. Sensitive response and sensitive response to different organic solvents. The composite exhibits excellent solvent sensitivity repeatability due to the restructure of continuous RGO networks after solvent volatilization.
【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】：TB332
【参考文献】
相关期刊论文 前1条
1 张立群,吴友平,王益庆,王一中,张慧峰,余鼎声,贺建芸;橡胶的纳米增强及纳米复合技术[J];合成橡胶工业;2000年02期
，本文编号：2139313
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