本文選題：功能化石墨烯納米片 + 磁攪拌研磨法　； 參考：《山東理工大學(xué)》2015年碩士論文

【摘要】：自從石墨烯被成功分離制備以來,一直是人們所研究的熱點(diǎn)。本文對石墨烯的制備及應(yīng)用進(jìn)行了綜述,提出了一種新穎、高效的制備石墨烯納米片的方法,并在此基礎(chǔ)上得到了功能化的石墨烯納米片(Functionalized Graphene Nanoplatelets,FGNPs)。同時(shí),論文也對FGNPs的改性和應(yīng)用進(jìn)行了論述,研究了其作為潤滑油添加劑的潤滑增效性能。論文的主要研究內(nèi)容概括如下:功能化石墨烯納米片的制備:以磁攪拌研磨法作為制備方法,通過弱磁性研磨介質(zhì)的高速旋轉(zhuǎn)所產(chǎn)生的摩擦力、碰撞力和剪切力將天然鱗片石墨以極高的效率破碎至納米尺寸,隨后又利用雙氧水的氧化性將其功能化。采用氮?dú)馕健EM、TEM、FTIR、TGA和XRD等手段進(jìn)行了表征。結(jié)果表明,研磨時(shí)間為4h時(shí)即可得到比表面為738.1 m2 g-1的石墨烯納米片,相對于原始石墨1.7 m2 g-1的比表面積增大了約434倍。FTIR結(jié)果顯示樣品表面具有羥基、羧基等含氧官能團(tuán)。XRD和SAED顯示出所制備樣品具有良好的結(jié)晶性。功能化石墨烯納米片的改性:利用功能化石墨烯納米片存在的羥基、羧基等含氧官能團(tuán),以帶有長鏈烷基的正十二烷基三乙氧基硅烷、硬脂酸、油酸等為改性劑,使FGNPs以化學(xué)鍵合的形式接枝長鏈烷基以改變其在潤滑油中的懸浮穩(wěn)定性。FTIR測試結(jié)果表明,改性后的石墨烯納米片具有對稱亞甲基和不對稱甲基峰出現(xiàn)。當(dāng)改性石墨烯納米片(Modified Graphene Nanoplatelets,MFGNPs)與未改性石墨烯納米片分散液相比較時(shí),在相同的離心速度和時(shí)間下前者有著更高的吸光度值,表明其具有更好的懸浮穩(wěn)定性。改性石墨烯納米片的摩擦學(xué)性能測試:利用改性石墨烯納米片的小尺寸和自潤滑特點(diǎn),作為添加劑添加到潤滑油中以增強(qiáng)潤滑油的潤滑效果。四球摩擦實(shí)驗(yàn)表明,相比較基礎(chǔ)油而言,當(dāng)MGNPs添加量為1 wt‰時(shí),平均摩擦系數(shù)從0.1170降低到0.0642,磨斑大小從482μm降低到353μm,分別降低了約45%和26.8%。當(dāng)添加量增加到1.5 wt‰時(shí),平均摩擦系數(shù)和磨斑直徑分別為0.0282、284μm,較之基礎(chǔ)油分別降低了75.9%和41.1%。這充分說明了改性石墨烯納米片在保證其良好的懸浮穩(wěn)定性的基礎(chǔ)上有著優(yōu)秀的潤滑增效功能。此外,本實(shí)驗(yàn)制備功能化石墨烯納米片所采用的磁攪拌研磨法是一種高效、環(huán)保、低成本的物理破碎法,可實(shí)現(xiàn)石墨烯納米片的大規(guī)模制備。本論文對功能化石墨烯納米片的制備效率也進(jìn)行了一定的探究。
[Abstract]:Since the successful separation and preparation of graphene, it has been a hot topic. In this paper, the preparation and application of graphene are reviewed, and a novel and efficient method for preparing graphene nanoparticles is proposed. On the basis of this, Functionalized Graphene Nanoplatelets (FGNPs) are obtained. At the same time, the modification and application of FGNPs were discussed, and its lubricating and synergistic properties were studied. The main research contents of this paper are summarized as follows: preparation of functional graphene nanoparticles: friction produced by high speed rotation of weak magnetic grinding medium by magnetic agitation grinding method. The natural flake graphite was crushed to nanometer size by impact force and shear force with high efficiency, and then functionalized by the oxidation of hydrogen peroxide. The structure was characterized by nitrogen adsorption, TGA and XRD. The results showed that graphene nanoparticles with a specific surface area of 738.1 m ~ 2 g ~ (-1) were obtained when grinding time was 4 h, and the specific surface area of the sample was increased by about 434-fold compared with that of the original graphite (1.7m ~ (2) g ~ (-1). The results showed that the surface of the sample had hydroxyl groups. The oxygen functional groups such as carboxyl group. XRD and SAED show that the prepared samples have good crystallinity. Modification of functionalized graphene nanoparticles: using hydroxyl, carboxyl and other oxygen-containing functional groups in functionalized graphene nanoparticles, using n-dodecyl triethoxy silane, stearic acid, oleic acid and so on with long chain alkyl as modifier, FGNPs was grafted with long chain alkyl in the form of chemical bonding to change its suspension stability in lubricating oil. FTIR results showed that the modified graphene nanoparticles had symmetrical methylene and asymmetric methyl peaks. When modified Graphene Nanoplatelets (MFGNPs) is compared with unmodified graphene nanoparticles, the former has higher absorbance at the same centrifugal rate and time, which indicates that the modified graphene has better suspension stability. The tribological properties of the modified graphene nanoparticles were tested. The small size and self-lubricating characteristics of the modified graphene nanoparticles were used as additives to enhance the lubricating effect of the lubricating oil. The four-ball friction experiment shows that the average friction coefficient decreases from 0.1170 to 0.0642 and the wear spot size decreases from 482 渭 m to 353 渭 m when the content of MGNPs is 1 wt 鈥，

本文編號：1841304