Preparation and characterization of aluminum oxide–poly(ethylene-co-butyl acrylate) nanocomposites

This article describes the preparation and characterization of composites containing poly(ethylene-co-butyl acrylate) (EBA–13 and EBA–28 with 13 and 28 wt % butyl acrylate, respectively) and 2–12 wt % (0.5–3 vol %) of aluminum oxide nanoparticles (two types differing in specific surface area and hydroxyl-group concentration; uncoated and coated with, respectively, octyltriethoxysilane and aminopropyltriethoxysilane). A greater surface coverage was obtained with aminopropyltriethoxysilane than with octyltriethoxysilane. An overall good dispersion was obtained in the EBA-13 composites prepared by extrusion compounding. Composites with octyltriethoxysilane-coated nanoparticles showed the best dispersion. The addition of the nanoparticles to EBA–28 resulted in poor dispersion, probably due to insufficiently high shear forces acting during extrusion mixing which were unable to break down nanoparticle agglomerates. The nanoparticles had no effect on the crystallization kinetics in the EBA–13 composites, but in the EBA–28 composites the presence of the nanoparticles led to an increase in the crystallization peak temperature, suggesting that the nanoparticles had a nucleating effect in this particular polymer. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

硅烷偶联剂对碳微球的表面化学修饰

首先采用混酸体系对碳微球(CMSs)表面进行氧化处理,使CMSs表面引入含氧官能团,进而以γ-(甲基丙烯酰氧)丙基三甲氧基硅烷(KH-570)与CMSs表面发生缩合反应,得到了表面有机修饰的CMSs.利用傅立叶红外光谱仪、场发射扫描电子显微镜、X射线光电子能谱等检测手段对各阶段的产物进行了形貌和结构表征,并研究了其在乙...     

碳钢硅-锆复合预处理工艺研究

目的为解决传统预处理工艺能耗高、环境污染严重的问题,在前期研制的硅烷化和锆化配方的基础上,进一步调整工艺参数,探索将硅烷化和锆化工艺合二为一,优化出性能优良的硅-锆金属预处理工艺。方法通过硫酸铜点滴实验、盐水浸泡实验、电化学极化曲线法测试转化膜的耐蚀性能,采用拉开法测试涂层在金属表面的附着力。使用SEM对转化膜的微观形貌进行表征。结果硅锆处理的最佳工艺参数为:pH=3.5,处理温度20℃,处理时间10 min。极化曲线测试结果表明,经硅锆处理后的碳钢腐蚀电流密度为未处理的1/40,膜层耐蚀性能良好。拉开法测得涂层在基体上的附着力达到11.48 MPa,完全满足一般预处理工艺要求。微观形貌分析显示,硅锆膜属于纳米级无定形型转化膜,膜层均匀、致密,能为金属表面提供有效防护。结论通过调整工艺参数,将硅烷化处理和锆化处理合二为一,获得性能优良的硅-锆复合膜。转化膜的耐蚀性能优良,与涂层附着力良好,满足预处理工艺要求。     

Surface Silanization of Polyethylene for Enhanced Adhesion

Low density polyethylene has been treated using a novel surface treatment process “SICOR” (“SIIane-on-CORona” treated polymer) in order to enhance adhesion with a range of adhesives including polyure-thane, methacrylate and cyanoacrylate. The process comprises two steps, i.e corona discharge followed by application of an organo-functional silane. The incorporation of surface hydroxyl groups onto the polymer surface enables organo-silane to create the hydrogen or covalent bonds with the oxidized polymer surface. The possibility of the creation of these bonds has been investigated using FTIR, XPS and wettability studies. The adhesion enhancement due to the new process is significant. Frequently, the strength increase exceeds 200% compared with the corona discharge treatment and more than 300% compared with LDPE priming using the “Loctite 770” polyolefin primer. The process is shown to be as good as, or better than, plasma treatment in terms of the strength increase following substrate treatment prior to adhesive bonding.     

硅烷处理N2O氧化苯生产苯酚催化剂抑制结碳失活研究

The main cause to the deactivation of ZSM-5 catalyst, used for oxidation of benzene to phenol (BTOP) by nitrous oxide, is that the carbon deposition on the catalyst surface blocks the mouth of pores of the catalyst.In the experiments, ZSM-5 catalyst was modified by chemical surface deposition of silicon, and then the effect of modification condition on the catalyst activation was studied. The catalyst samples were characterized by XRF,EPS, XRD, TEM, N2 adsorption at low temperature, pyridine adsorption-infrared technique and etc. All the above results show that the uniform SiO2 membrane can be formed on ZSM-5 crystal surface. The SiO2 membrane covers the acid centers on ZSM-5 surface to inhibit surface coking, to avoid or decrease the possibility of ZSM-5 pore blockage so that the catalyst activity and stability can be improved efficiently. The optimum siliconiting conditions determined by the experiments are as follows: 4% load of silanizing agent, volume (ml)/mass (g) ratio of hexane/ZSM-5=15/1, and 16 h of modification time. Compared with the samples without siliconiting treatment,the samples treated under the above optimum condition can increase the productivity of phenol by 14% for 3 h reaction time and by 41% for 6 h reaction time respectively.     

Si69在白炭黑补强溶聚丁苯橡胶中的应用研究

研究了不同温度下Si69改性白炭黑的硅烷化反应、改性白炭黑对溶聚丁苯橡胶（SSBR）力学性能以及Si69对SSBR硫化特性的影响。结果表明,Si69与白炭黑发生硅烷化反应的最佳温度为140℃;Si69能够增大胶料的最大转矩（MH）和交联密度;Si69改性白炭黑补强SSBR的混炼胶在140℃静置处理后,其综合力学性能最佳。     

场效应器件表面修饰对DNA测试性能影响的研究

对比甲醇-盐酸混合物及硫酸处理对场效应器件(Field-effect device,FED)电化学测试性能的影响.实验结果表明,FED表面经过两种方式处理,其电化学阻抗测试特性发生变化,表现在阻抗的虚部值(用Zq表示)随加在FED器件与参比电极之间的电压的变化特性(用Zq-V曲线表示)发生改变.经过硫酸处理的器件的Zq-V曲线相对于未处理器件有微小偏移;而甲醇-盐酸体系处理后曲线在耗尽层区的斜率有所下降,表明这种处理对器件测试性能有负向的影响.经硅烷化固定在表面的氨基采用荧光标记,荧光测试结果表明,两种表面处理方式对硅烷化效果影响不大.进一步通过共价连接在硅烷化FED表面引入探针DNA分子,制备基于FED的DNA传感器.与目标DNA分子杂交反应后,实验表明,硫酸处理的测试结果要好于甲醇-盐酸的处理方法.     

Substrate-Independent and Re-Writable Surface Patterning by Combining Polydopamine Coatings,Silanization, and Thiol-Ene Reaction

Polydopamine coating is a unique, simple, and substrate-independent surface functionalization strategy. Techniques for secondary functionalization, patterning, and re-functionalization of polydopamine modified materials are important to broaden the scope of applications of such materials in a variety of fields. Here, a facile and substrate-independent strategy for surface functionalization and patterning is presented. This approach combines the advantages of three important methods: facile and substrate-independent polydopamine coating, versatile gas phase silanization, and rapid thiol-ene photoclick reaction for patterning. They demonstrate equally efficient functionalization and patterning of diverse materials, such as glass, polytetrafluoroethylene, aluminum, polypropylene, or polyethylene. They also show the possibility of controlled chemical removal of the patterns or surface functionalization by treatment with tetrabutylammonium fluoride, which allows re-modification or re-patterning of the substrate. Thus, this universal and powerful approach for substrate independent surface modification and patterning can significantly facilitate the development of novel functional materials and devices useful for various applications.     

N,O-双三甲基硅基乙酰胺的合成进展

简述了N,O-双三甲基硅基乙酰胺的应用,论述了国内外合成工艺路线,并对其优缺点进行讨论。     

多孔Si光学干涉法生物传感器的研究

实验制备多孔Si材料作为传感器载体,通过H2O2浸泡的方法使其表面形成Si-OH键,然后对样品进行硅烷化处理。用戊二醛作为偶联剂,通过共价键偶联法将血管紧张素-Ⅱ(Ang-Ⅱ)抗体固定到多孔Si的孔洞中。分别滴加不同浓度的抗原使其发生反应,测量傅里叶变换红外谱(FT-IR)和加入抗体前后反射谱的变化,结果表明,硅烷化效果明显,生物抗原较好固定,抗原抗体反应前后反射谱有明显红移,且红移量于滴加抗原浓度增加而增加,并呈现抗原抗体浓度于红移量的非线性关系。