Surface modification on nanoscale titanium dioxide by radiation: Preparation and characterization

Electron beam mutual radiation to induce graft polymerization has been carried out respectively, between nanoscale anatase‐ or rutile‐titanium dioxide particles surface and methyl methacrylate (MMA). The composition and properties of surface modified titanium dioxide were investigated by a number of surface sensitive techniques: X‐ray photoelectron spectrum (XPS), FTIR, X‐ray diffraction (XRD), and NMR. Results of the technological measurements show how surface chemistry is affected throughout the surface modification process, finally leading to a complete and homogeneous vinyl compound overlayer on top of the titanium dioxide samples. In comparison with stereochemical structures of the graft molecular chains and the PMMA induced by radiation polymerization, the surfaces of the oxides are considered to provide a template for the graft polymerization. The grafted titanium dioxide is found to produce a stable colloidal dispersion, in good solvents for the grafted polymer, and the dispersibility of grafted dioxides is influenced by temperature. In addition, the wettability of the surface of titanium dioxide to water is readily controlled by grafting of hydrophilic or hydrophobic polymers. Based on the above results, it is concluded that MMA is covalently linked to the surface of titanium dioxide by a surface modification process. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci, 100: 3510–3518, 2006     

超分散剂对二氧化钛粉体分散稳定性的影响

采用超分散剂改性二氧化钛,研究超分散剂浓度、用量、温度等条件对其分散稳定性的影响,找出最佳改性方案。     

Surface modification of titanium dioxide for electrophoretic particles

To prepare stable electrophoretic ink (E Ink) needs color particles to be uniformly dispersed in the organic medium. Thus, t-he modification of inorganic particle surface is required. In this paper, Titanium dioxide modified by alumina has been studied. The surface composition and structures of modified particles have been characterized by X-ray photoelectron spectrometer (XPS), X-ray diffractometer (XRD) and Fourier transform infrared spectrometer (FT-IR). The dispersibility and electrophoretic mobility of these particles in tetrachloroethylene (TCE) have been investigated by laser particle size analyzer, static sedimentation and electrophoretic instrument. Effects of temperature, pH value and stirring rate on the dispersibility and the charge property of samples have been discussed. The results indicate the settle time of modified TiO₂ can last 120 h with the response time of 35 s under the optimized modifying conditions, in which temperature is 85°C–90°C, pH is 8–9 and stirring rate is 800 r·min⁻¹. The dispersibility and electrophoretic mobility have been significantly improved, which means that the modified TiO₂ is suitable for electrophoretic ink particles. __________ Translated from Journal of Chemical Engineering of Chinese Universities, 2006, 20(6): 893–897 [译自: 高校化学工程学报]     

提高二氧化钛光催化性能的研究进展

对过渡金属离子掺杂、贵金属表面沉积、表面光敏化、表面超强酸化等几种提高TiO2 光催化剂活性的方法进行了综述 ;介绍了近年来为了提高TiO2 光催化过程的效率 ,而发展形成的微波场作用下光催化反应、热催化与光催化的耦合反应、室温等离子体光催化反应、生物光催化反应、电场助光催化反应等几种新型高效光催化反应技术的研究现状与进展 ;并对TiO2 光催化的应用进行了展望。     

Plasma induced graft polymerization of acrylic acid onto polypropylene monofilament

Plasma induced graft polymerization of acrylic acid onto polypropylene (PP) monofilament was carried to introduce carboxyl functionality on its surface. The monofilament was treated with oxygen plasma to create hydroperoxide groups and subsequent graft polymerization was initiated on this exposed monofilament. It was observed that in the absence of an added inhibitor, the grafting did not proceed because of the extensive homopolymerization which left behind hardly any monomer for the grafting reaction. The addition of ferrous sulfate to the grafting medium led to the homopolymer free grafting reaction. The addition of organics, such as methanol, butanone, and acetone led to complete inhibition of the homopolymerization at 60% content. However, the addition of butanone led to much lower degree of grafting than methanol and acetone. The contact angle of the monofilament showed drastic reduction by plasma treatment and by the subsequent grafting of acrylic acid. The grafting in ferrous sulfate medium showed higher contact angles as compared to the grafting in organic medium. The surface morphology was significantly influenced by the nature of the additive in the grafting medium. © 2007 Wiley Periodicals, Inc. JAppl Polym Sci, 2008     

硅烷偶联剂KH-570湿法改性TiO2的结构与性能研究

利用硅烷偶联剂(KH-570)对纳米二氧化钛(TiO2)进行湿法改性处理.采用静态沉淀法、亲油化度、接触角、X射线光电子能谱( XPS)和傅立叶红外光谱(FT-IR)等手段对改性效果进行分析表征,探析湿法改性机理.研究表明KH-570以化学链形式结合于TiO2表面,改性后TiO2的表面性质由亲水变为亲油.     

聚酯消光剂二氧化钛粉体的改性

采用多磷酸酯表面活性剂(ADDP)与十二烷基苯磺酸钠／磷酸酯(LAS／PE)两种表面活性剂体系对聚酯消光剂二氧化钛粉体(TA-300)改性。结果表明:质量分数均为3％的ADDP与LAS／PE体系改性的TA-300对去离子水的接触角由0°分别增到了130°与109°;吸油量由0.74 mL／g均降到了约0.28 mL／g,糊粘度由3 930 mPa·s分别降到了230 mPa·s和240 mPa·s。DSC表明:ADDP体系的放热峰在360℃左右,热稳定性优于LAS／PE体系。在PET中加入ADDP(质量分数为3％)改性的TA-300,熔融挤出时的网前压力在3.2-4.3 MPa,改性TA-300在PET中有很好的分散性和热稳定性。     

硅烷偶联剂水解及对钛白粉的改性研究

通过电导率对乙烯基三乙氧基硅烷偶联剂（A-151）的水解行为进行研究,考察了pH、水与A-151体积比和温度对硅烷水解行为的影响,利用A-151的水解特性,对经锆铝二元包覆后的钛白粉进行表面改性,并采用表面接触角测试仪、红外光谱和扫描电镜对有机改性后的二氧化钛进行表征。表面接触角测试显示改性后的二氧化钛制片表面润湿角达108.2°;改性后的粉体在波数为3 078 cm-1处出现了对应的烯烃C-H伸缩振动吸收峰;扫描电镜照片显示改性后的二氧化钛粒子的分散性得到了改善。     

纳米二氧化钛粉体的制备及工艺研究

本文以钛白粉为原料自制硫酸钛溶液，采用水热合成法制备出分散性较好，粒径约为10nm的纳米二氧化钛粉体。并通过对比实验对其主要工艺参数进行了分析与讨论。     

多元改性二氧化钛的制备及其性能研究

采用浸渍法制备了铁-钐-镱-二氧化钛改性光催化剂,以苯酚为目标降解物,讨论了影响光催化剂性能的因素和提高光催化剂性能的方法。通过FE-SEM、XRD、UV-Vis等表征手段初步探讨了共掺杂提高二氧化钛光催化活性的机理。实验结果表明：常温、常压下,质量浓度为20 mg/L的苯酚废水（pH=7）,当催化剂加入量为 2.5 g/L、焙烧温度为550 ℃、金属（铁、钐、镱）掺杂量各为0.5%（质量分数）时,经4 h紫外光照其对苯酚的去除率可达90%以上。改性后的二氧化钛光催化剂在可见光下也能够显示出很好的活性。     

纳米级二氧化钛粉体的制备方法和发展趋势

介绍了纳米级TiO2 的制备方法和研究现状 ,讨论了气相法和液相法合成纳米级TiO2 的优缺点 ,指出当前纳米级TiO2 的主要研究方向。我国应加快开发适合国情的纳米级TiO2 生产新工艺     

超微细粉体材料二氧化钛的开发和应用

介绍了超微细二氧化钛的制备方法，对气相法和液相法合成纳米级二氧化钛的优缺点进行了比较，介绍了改性二氧化钛的表面处理方法及应用，建议我国应尽快开发纳米级二氧化钛生产工艺。     

Cotton fabric graft copolymerization using microwave plasma. II. Physical properties

Microwave plasma treatments were applied to lightweight cotton fabric with oxygen, nitrogen, and argon at various microwave power levels and exposure times. The results showed significant effects from the type of plasma, microwave power, and treatment time on the fabric weight loss. Oxygen plasma treatment generates higher weight loss than argon plasma and nitrogen plasma. The breaking strength of the treated fabric was affected mainly by longer exposure time to the plasma. The active centers created within the cellulose macromolecules were used to initiate copolymerization reactions with the vinyl laurate monomer [CH₃(CH₂)₁₀COOCH?CH₂]. The grafted cotton fabric showed excellent water repellency properties. Repeated home laundering of the treated cotton fabrics revealed no significant effect on the water contact angle or on the quantity of grafted vinyl laurate monomer as determined by universal attenuated total reflectance Fourier transform IR, demonstrating the good durability of the treatment that was applied. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 896–902, 2005     

原位聚合法表面改性TiO2研究

用阴离子表面活性剂十二烷基苯磺酸钠(LAS)处理TiO2粉体,后以原位聚合的方法得到了TiO2的无机有机复合粒子,并对复合粒子进行了必要的表征,探索了复合粒子的形成机理,研究了聚合条件对复合粒子形成过程的影响。结果表明TiO2复合粒子的表面性质已由亲水转变为亲油,可以认为表面包覆了St-BA共聚物的TiO2复合粒子。     

Ar等离子体改性PTFE膜接枝丙烯酸研究

研究利用Ar等离子体为引发手段对聚四氟乙烯(PTFE)膜进行表面处理,最终实现在PTFE膜表面接枝丙烯酸.通过XPS和ATR-FTIR对改性膜的表面进行表征,表明在PTFE膜的表面形成一层聚丙烯酸(pAAc)薄膜.PTFE-g-pAAc膜的表面亲水性及其表面稳定性比等离子改性PTFE膜(PTFE modified by plasma)具有较大的改善,克服了等离子体改性效果不稳定的缺点.本研究拓展了PTFE膜材料在其他各相关领域的应用,对其他高分子材料也有一定的借鉴意义.     

纳米二氧化钛表面改性与应用研究进展

纳米二氧化钛作为一种重要的纳米材料,在陶瓷材料、催化剂载体等领域有着广泛的应用。在纳米二氧化钛粉体的工业化生产中,表面处理技术是必不可少的关键步骤之一,因为改性方法的选取以及包覆物的性质会直接影响产品的应用范围。在综合分析相关文献的基础上,概述了有关纳米二氧化钛粉体表面包覆的相关机理、方法和制备过程中的控制因素等内容;主要介绍了近几年世界纳米二氧化钛粉体表面改性的研究成果及进展,并提出了今后的研究方向。     

熔盐法处理富钛渣制备金红石型TiO_2

工业生产钛白粉的方法主要有硫酸法和氯化法两种,但这两种方法都存在环境污染严重的问题。本文提出了一种常压、低温下钠碱熔盐分解富钛渣制备金红石型二氧化钛的新工艺,从生产源头消除了对环境的污染,实现钛资源的可持续发展。介绍了该反应的制备、水洗、固相离子交换-水解耦合和煅烧过程。实验结果表明,该工艺可以制得理想的金红石型二氧化钛,二氧化钛含量为96.66%。     

煅烧高岭土与钛白粉的湿法研磨复合工艺研究

采用湿法超细研磨方法对煅烧高岭土与钛白粉进行机械物理复合,通过正交试验和单因素试验研究了研磨复合工艺条件对煅烧高岭土/钛白粉复合粉体材料白度、遮盖力等物理性能的影响.结果表明,复合配比、研磨时间、pH和悬浮液质量分数是影响包覆效果的主要因素;在煅烧高岭土/钛白粉复合质量配比50:50、研磨时间10 min、pH=5、悬浮液高岭土质量分数50%条件下,制得的复合粉体在主要物理性能指标上接近钛白粉,可作为钛白粉的代用材料.     

深还原钛渣硫酸法制取钛白实验研究

以含钛铁精矿直接还原冶炼的含钛物料（深还原钛渣）为原料,对硫酸法制取颜料级钛白粉的工艺进行了研究。实验结果表明,深还原钛渣具有良好的酸解性能,酸解率可达97%;酸解后得到的钛液过滤性能好;但酸解钛液中氧化镁和氧化铝浓度过高,所以直接以该钛液为原料制得的钛白颜料性能差。采用深还原钛渣和钛精矿按一定比例混合酸解,可以避免钛液杂质含量过高对最终钛白产品质量造成的影响。深还原钛渣较佳用量为不高于钛原料总质量的20%。     

Ar等离子体改性PTFE膜接枝丙烯酸的研究

本研究利用Ar等离子体为引发手段对PTFE膜进行表面处理,最终实现在PTFF膜表面接枝丙烯酸。通过XPS和ATR-FTIR对改性膜的表面进行表征,表明在PTFE膜的表面形成一层聚丙烯酸（PAAc）薄膜。PTFE—g—PAAc膜的表面亲水性及其表面稳定性比等离子改性PTFE膜具有较大的改善,克服了等离子体改性效果不稳定的缺点。本研究拓展了PTFE膜材料在其他各相关领域的应用,对其他高分子材料也有一定的借鉴意义。