【摘要】：橡膠是一種高彈性高分子柔性材料,具有金屬材料、無機(jī)非金屬材料所不具有的性質(zhì),在國民生產(chǎn)中有著重要的應(yīng)用,常用來制造輪胎等動(dòng)態(tài)條件下使用的制品。由于橡膠這種具有熵彈性的高分子鏈導(dǎo)熱性較差,很容易在動(dòng)態(tài)疲勞過程中使橡膠制品產(chǎn)生微小裂紋,致使橡膠制品原有的特性和疲勞壽命大大降低,對于生產(chǎn)生活應(yīng)用造成不小損失。本文針對橡膠原料中極具耐寒性和抗老化性能優(yōu)異的順丁橡膠(BR)作為實(shí)驗(yàn)研究的基底材料,通過炭黑、白炭黑的填充以及與天然橡膠共混復(fù)合來探究順丁橡膠的裂紋的產(chǎn)生以及開裂機(jī)理;然后從宏觀和微觀角度相結(jié)合去解釋裂紋的生長過程,總結(jié)出橡膠動(dòng)態(tài)疲勞失效的新理論,對于延長橡膠在動(dòng)態(tài)過程中的使用壽命提出新思路。在論文討論的第一部分中,通過使用不同粒徑的白炭黑填充順丁橡膠,在橡膠體系中構(gòu)筑不同的填料網(wǎng)絡(luò)結(jié)構(gòu)來研究裂紋的生長以及擴(kuò)展形態(tài),發(fā)現(xiàn)并提出粒子形態(tài)的規(guī)整性對順丁橡膠性能產(chǎn)生強(qiáng)烈的影響。通過在白炭黑填料中加入硅烷偶聯(lián)劑(Si69)進(jìn)行對比試驗(yàn)進(jìn)一步表明,提升粒子與橡膠基體的相互作用可以有效的降低順丁橡膠裂紋擴(kuò)展速度。此外,也表明白炭黑與硅烷偶聯(lián)劑有效接枝率,即硅烷偶聯(lián)劑兩端分別連接橡膠分子鏈與納米粒子,也是調(diào)控橡膠裂紋擴(kuò)展速度的關(guān)鍵。在第二部分中,通過對同一粒徑不同份數(shù)的炭黑填充順丁橡膠,將其性能進(jìn)行橫向?qū)Ρ?實(shí)驗(yàn)結(jié)果表明,炭黑的填充份數(shù)與機(jī)械性能存在競爭關(guān)系。隨著炭黑填充份數(shù)的增加,其補(bǔ)強(qiáng)的順丁橡膠復(fù)合材料的力學(xué)及其他機(jī)械性能明顯增加;但是炭黑填充份數(shù)過多則導(dǎo)致其在橡膠基體內(nèi)形成聚集體,影響自身性能的發(fā)揮。所以,探究合適炭黑填充份數(shù)對于降低橡膠裂紋擴(kuò)展的速率則顯得尤為重要。在第三部分中,由于天然橡膠與順丁橡膠的相容性較好,通過不同比例共混所產(chǎn)生的不同的相態(tài)結(jié)構(gòu)探究與橡膠裂紋擴(kuò)展的關(guān)系。實(shí)際的測速結(jié)果與掃描探針顯微鏡拍攝的相圖結(jié)合分析表明,共混體系中相尺寸越小,相界面越模糊,越易降低裂紋生長的速率,我們得出裂紋尖端的應(yīng)力集中容易在薄弱的相界面進(jìn)行能量釋放,從而破壞順丁橡膠基體結(jié)構(gòu)而導(dǎo)致橡膠制品疲勞失效。
[Abstract]:Rubber is a kind of high elastic polymer flexible material, which has the properties of metal material and inorganic nonmetallic material. It has important application in national production, and is often used to manufacture products under dynamic conditions such as tire. Because of the poor thermal conductivity of rubber, a polymer chain with entropy elasticity, it is easy to produce tiny cracks in the dynamic fatigue process of rubber products, thus greatly reducing the original characteristics and fatigue life of rubber products. For the production and life of the application caused no small loss. In this paper, cis-butadiene rubber (BR), which has excellent cold-resistance and anti-aging properties in rubber raw materials, was used as the substrate material of experimental study. The crack generation and cracking mechanism of cis-butadiene rubber were investigated by filling with silica and blending with natural rubber. Then the new theory of dynamic fatigue failure of rubber is summarized from the view of macroscopic and microcosmic to explain the growth process of crack, and a new idea for prolonging the service life of rubber in dynamic process is put forward. In the first part of the thesis, the crack growth and propagation morphology were studied by using different particle size silica filled with cis-butadiene rubber and constructing different filler network structure in rubber system. It was found that the regularity of particle morphology had a strong effect on the properties of cis-butadiene rubber. By adding silane coupling agent (Si69) into silica filler, it is further shown that the interaction between the lifting particles and the rubber matrix can effectively reduce the crack growth rate of cis-butadiene rubber. In addition, it is also shown that the effective grafting rate of silica and silane coupling agent, that is to say, the two ends of silane coupling agent are connected with rubber molecular chain and nanoparticles respectively, is also the key to regulate the crack growth rate of rubber. In the second part, the properties of cis-butadiene rubber filled with carbon black with the same particle size and different content were compared horizontally. The experimental results showed that the filling fraction of carbon black had a competitive relationship with the mechanical properties. The mechanical and other mechanical properties of the reinforced cis-butadiene rubber composites increased with the increase of carbon black filling fraction, but too many carbon black fillers resulted in the formation of aggregates in the rubber matrix, which affected the exertion of the properties of the composites. Therefore, it is very important to find out the appropriate fraction of carbon black to reduce the rate of rubber crack growth. In the third part, due to the good compatibility between natural rubber and cis-butadiene rubber, the relationship between the different phase structure and the crack propagation of rubber was investigated by mixing with different proportion. The combination of the actual velocity measurement results and the phase diagram taken by the scanning probe microscope shows that the smaller the phase size is, the more fuzzy the phase interface is and the easier it is to reduce the rate of crack growth. It is concluded that the stress concentration at the crack tip is easy to release energy at the weak phase interface, thus destroying the matrix structure of cis-butadiene rubber and resulting in fatigue failure of rubber products.
【學(xué)位授予單位】：寧波大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TQ333.2;TB33

【參考文獻(xiàn)】

相關(guān)期刊論文 前3條

1 劉泳濤;董為民;石路穎;姜連升;;稀土順丁橡膠的性能和應(yīng)用[J];合成橡膠工業(yè);2008年05期

2 孟春財(cái);陳建;張敬雨;金永中;伍雅峰;;炭黑對橡膠增強(qiáng)機(jī)理的研究現(xiàn)狀[J];合成橡膠工業(yè);2012年02期

3 李玉芳,伍小明;國內(nèi)外順丁橡膠的市場分析[J];上�；�;2004年08期

相關(guān)碩士學(xué)位論文 前2條

1 高勛朝;填充橡膠材料的疲勞性能研究[D];哈爾濱工業(yè)大學(xué);2006年

2 齊興國;NR/EPDM并用橡膠的共硫化性能研究[D];青島科技大學(xué);2007年

，

本文編號：2362732