【摘要】：為降低油井水泥石脆性,保持油井水泥環(huán)的完整性,解決油氣井開采安全隱患,本文將橡膠顆粒摻入到水泥基材中。為改善橡膠顆粒表面的疏水特性,增強(qiáng)橡膠顆粒與水泥基體的粘結(jié)力,本文采用低溫等離子體法對廢舊輪胎橡膠顆粒進(jìn)行了表面處理。對低溫等離子體改性橡膠顆粒表面性能、改性后橡膠顆粒表面的時效性和低溫等離子體接枝改性橡膠顆粒的表面特性及與水泥基體的粘結(jié)性進(jìn)行了研究。本文通過接觸角測試、分散性測試對低溫等離子體改性橡膠顆粒表面潤濕性的改變,優(yōu)選出最佳改性參數(shù)。通過比表面積及孔徑測試儀測試橡膠顆粒比表面積,通過紅外測試橡膠顆粒表面基團(tuán)變化情況,來表征低溫等離子體改性對橡膠顆粒表面結(jié)構(gòu)的影響。通過X射線電子能譜,測試橡膠顆粒表面元素變化,研究低溫等離子體改性橡膠顆粒表面的作用機(jī)理。通過SEM觀察低溫等離子體改性前后橡膠顆粒的表面形貌。將低溫等離子體改性后橡膠顆粒按照0-5%質(zhì)量比摻入到水泥中,制成水泥漿體,考察低溫等離子體改性后橡膠顆粒對水泥漿體性能的影響。將水泥漿體在30℃和90℃,分別測試養(yǎng)護(hù)1天、3天、7天、14天和28天水泥石的抗壓強(qiáng)度、抗折強(qiáng)度和抗拉強(qiáng)度,考察低溫等離子體改性后橡膠顆粒對水泥石力學(xué)性能的影響。測試水泥石三軸力學(xué)性能,考察低溫等離子體改性后橡膠顆粒對水泥石變形能力的影響。通過SEM觀察橡膠顆粒與水泥基材界面粘結(jié)情況。并將低溫等離子體改性后橡膠顆粒放置1天、10天和20天,考察橡膠顆粒表面性能的變化及與水泥基材粘結(jié)性能的影響,來研究低溫等離子體改性橡膠顆粒表面的時效性。通過低溫等離子體汽化接枝水,來改善低溫等離子體改性的時效性。結(jié)果發(fā)現(xiàn),低溫等離子體改性后橡膠顆粒表面潤濕性明顯增強(qiáng),接觸角降低至32.7°。比表面積增大,在3129cm-1、1625cm-1、1440cm-1、3440cm-1特征吸收帶加強(qiáng),所對應(yīng)的是-CH2、-CH鍵、-C=C-鍵和-OH鍵,材料表面O/C比提高。因為低溫等離子改性時,等離子體將橡膠粉表面的-C-C-、-C-H鍵被打斷,斷裂后的碳自由基可能形成-C=C-鍵,或者與氧等離子或原子氧反應(yīng),產(chǎn)生含氧極性基團(tuán)-C-O-鍵或-C=O鍵,使得橡膠顆粒表面的親水性得到改善。將改性后橡膠顆粒摻入到水泥漿體中,發(fā)現(xiàn)低溫等離子改性橡膠顆粒能有效改善水泥石抗壓強(qiáng)度的衰退,提高抗折強(qiáng)度和抗拉強(qiáng)度,降低彈性模量,增大水泥石變形能力。受低溫等離子體改性時效性影響,橡膠顆粒表面性能均略有降低,但仍優(yōu)于未處理橡膠顆粒。通過低溫等離子體汽化接枝水來改善低溫等離子體改性的時效性,接枝改性后的橡膠顆粒表面性能較好,與水泥基材粘結(jié)緊密。
[Abstract]:In order to reduce the brittleness of oil well cement stone, keep the integrity of oil well cement sheath and solve the hidden trouble of oil and gas well production safety, rubber particles were mixed into cement substrate in this paper. In order to improve the hydrophobic properties of rubber particles and enhance the adhesion between rubber particles and cement matrix, the surface treatment of waste tire rubber particles was carried out by low temperature plasma method. The surface properties of rubber particles modified by low-temperature plasma, the time-effect of modified rubber particles, the surface characteristics of rubber particles modified by low-temperature plasma grafting and the adhesion between rubber particles and cement matrix were studied. In this paper, the surface wettability of rubber particles modified by low temperature plasma was changed by contact angle test and dispersion test, and the optimum modification parameters were optimized. The effect of low temperature plasma modification on the surface structure of rubber particles was characterized by measuring the specific surface area and pore size of rubber particles by measuring the specific surface area of rubber particles and the change of the surface groups of rubber particles by infrared spectroscopy. The surface element changes of rubber particles were measured by X-ray electron spectroscopy, and the mechanism of modification of rubber particles surface by low temperature plasma was studied. The surface morphology of rubber particles before and after low temperature plasma modification was observed by SEM. The rubber particles modified by low-temperature plasma were added into cement according to the mass ratio of 0% to 5%. The effect of rubber particles modified by low-temperature plasma on the properties of cement paste was investigated. The compressive strength, flexural strength and tensile strength of cement paste were measured at 30 鈩，

本文編號：2441711