二氧化硅表面的APTS修饰

3-氨丙基三乙氧基硅烷(APTS)修饰的二氧化硅在生物化学、分析、催化、电子学等领域具有重要的应用前景.本文对近年来APTS修饰二氧化硅的研究进展进行了简要的概述,介绍了APTS修饰二氧化硅的典型方法和APTS修饰层的表征手段,探讨了不同修饰方法可控性及对所形成的APTS层结构及稳定性的影响.     

二氧化硅表面的APTS修饰

3-氨丙基三乙氧基硅烷（APTS）修饰的二氧化硅在生物化学、分析、催化、电子学等领域具有重要的应用前景。本文对近年来APTS修饰二氧化硅的研究进展进行了简要的概述,介绍了APTS修饰二氧化硅的典型方法和APTS修饰层的表征手段,探讨了不同修饰方法可控性及对所形成的APTS层结构及稳定性的影响。     

二氧化硅表面的GPTMS修饰

γ-(2,3-环氧丙氧基)丙基三甲氧基硅烷(GPTMS)是一种重要的硅烷偶联剂,由GPTMS修饰的纳米二氧化硅(GPTMS-SiO2)正在被广泛应用.本文对近年来GPTMS修饰二氧化硅的研究进行了简要概述:介绍了GPTMS修饰纳米二氧化硅的典型方法、修饰机理及存在的问题;归纳了FT-IR、XPS、NMR、元素分析、AFM等表征GPTMS 修饰层手段及GPTMS-SiO2表面环氧基的测定方法;探讨了不同修饰方法对所形成的GPTMS层结构及稳定性的影响;阐述了GPTMS修饰二氧化硅在色谱固定相、生化分析分离、光学材料、涂料黏合剂工业、介孔催化等领域的应用;并对其新的合成方法、分析评价体系、活性基团的测定方法及应用领域等作了展望.     

表面修饰纳米二氧化硅及其与聚合物的作用

本文综述了近几年国内外对纳米二氧化硅的表面化学修饰及其在聚合物基纳米复合材料中与基体作用方式的研究工作。对纳米SiO₂进行表面修饰可以改善纳米颗粒与聚合物基体间的亲和性,同时可以使纳米SiO₂表面功能化,有利于SiO₂与聚合物基体间形成强的结合力。纳米SiO₂与聚合物基体间可以以吸附力、氢键、共价键等方式结合,不同的结合方式对材料性能也会产生不同程度的影响。     

微结构与表面修饰对二氧化硅多孔薄膜疏水性能的影响

通过引入聚乙二醇(PEG)改性传统二氧化硅(SiO2)溶胶,得到了粒径分布较宽且粒径可控的溶胶。比较了六甲基二硅氮烷(HMDS)溶胶内修饰和薄膜表面修饰以及溶胶粒径对SiO2薄膜疏水性能的影响。采用动态光散射粒度仪定量测试了二氧化硅溶胶老化过程中粒度的变化,用原子力显微镜、接触角测试仪、红外光谱仪、紫外-可见-近红外分光光度计分别对薄膜的表面形貌、表观静态接触角、薄膜成分及透光率等进行了测量。结果表明:PEG的添加可有效增大溶胶粒度从而增大薄膜的粗糙度,提高薄膜的疏水性。表面修饰效果受修饰方式和SiO2粒径影响,粒径较小时有利于溶胶内修饰,粒径较大时有利于对薄膜修饰。经过表面修饰剂(HMDS)的气氛处理得到了接触角为152°的超疏水薄膜,而且相比溶胶内修饰可以减小薄膜透光率的损失。     

二氧化硅栅绝缘层的制备与表面修饰

研究了有机薄膜晶体管的二氧化硅栅绝缘层的性质。二氧化硅绝缘层的制备采用热生长法，氧化气氛是O₂(g)+H₂O(g)，工艺为干氧-湿氧-干氧的氧化过程。制得的绝缘层漏电流在10^-9 A左右。以该二氧化硅作为有机薄膜晶体管的栅绝缘层，并五苯作为有源层制作了有机薄膜晶体管器件。实验表明采用十八烷基三氯硅烷(OTS)进行表面修饰的器件具有OTS/SiO₂双绝缘层结构，可以有效地降低SiO₂栅绝缘层的表面能并改善表面的平整度。修饰后器件的场效应迁移率提高了1.5倍、漏电流从10^-9 A降到10^-10 A、阈值电压降低了5 V、开关电流比从10⁴增加到10⁵。结果显示具有OTS/SiO₂双绝缘层的器件结构能有效改进有机薄膜晶体管的性能。     

丙烯酸酯单体修饰二氧化硅纳米粒子的制备

采用两步法将可聚合的乙烯基单体键接到S iO2纳米粒子表面合成了大分子单体.首先利用过量的甲苯-2,4-二异氰酸酯(TD I)对S iO2粒子表面进行化学修饰合成出表面带有高反应活性-NCO基团的功能化S iO2粒子(S iO2-TD I),再利用S iO2-TD I与丙烯酸羟丙酯(HPA)反应将碳-碳双键引入到S iO2粒子表面.系统考察了反应条件对TD I与S iO2反应的影响.此外,利用红外光谱和透射电镜对大分子单体进行表征,结果表明S iO2大分子单体能均匀地分散在甲苯中,没有发生明显团聚.     

二氧化硅纳米粒子表面修饰及其表征

采用溶胶-凝胶法合成粒径在50—150nm范围内的二氧化硅（SiO2）纳米粒子。用甲基丙烯酸-3-（三甲氧基硅基）丙酯（MPS）对SiO2纳米粒子表面进行修饰,使其表面接枝能参与自由基聚合反应的碳碳双键基团。用元素分析、FTIR、^13C CP／MASNMR和^29Si CP／MASNMR等手段对修饰过的SiO2纳米粒子进行表征,以确证MPS接枝在SiO2纳米粒子上。分析修饰过的SiO2纳米粒子的^29Si CP／MASNMR和FTIR谱图,还可初步推断MPS接枝在SiO2纳米粒子表面的机理：MPS首先发生水解缩合反应形成低聚物,然后通过氢键作用吸附到SiO2纳米粒子表面,最后MPS低聚物中未缩合的硅羟基与SiO2纳米粒子表面的硅羟基发生缩合反应。     

半导体光催化剂的表面修饰

从半导体光催化剂表面修饰的类型、机理及效果出发,对其研究进展作了综合评述.     

纳米二氧化硅粒子对聚氯乙烯膜的表面结构及浸润性能的调控作用

报道了一种简便的调控聚合物材料表面结构及浸润性能的方法.利用流延成膜和纳米二氧化硅粒子的印迹修饰作用,制备出3种具有不同表面结构的聚氯乙烯(PVC)膜,膜的浸润性能表现为与水的接触角从103°的疏水性变为65°的亲水性,再改变至130°的疏水性.扫描电镜结果表明印迹修饰后的PVC膜具有纳米和微米尺寸的凹凸表面结构.通过对比实验证实了溶剂氯仿和NaOH溶液并不影响膜表面的疏水性能.     

Surface Modification of Silica Gels as Carrier for AminoacylaseImmobilization

IrnmobilisedaIninoacylaseisanotablecatalystforthekineticresolutionofN-acetyl-D,L-aIninoacidsandquitealotofresearchworkhasbeeninvolvedonaminoacylase~bilisationswithitscarriers.lTheauthorshaverePortedthattheaIninosilicagelspreparedbyanlinProvedmethodwereeffechveforchymotryPsininunobilisahon,'l'butitwasnotproperforaIninoacylasetriobilisahon.InordertodevelopasahsfactorysurfacesmictUreofsilicagelsforaIninoacylasetriobilisation,tWokindsofreactivegrouPs,theN,N-diethylaIninogrouPandthehydroxygr…     

水性纳米硅溶胶的表面改性及其应用研究

将几种功能性有机硅烷偶联剂与不同pH值的无机纳米硅溶胶水溶液通过表面改性反应和溶胶-凝胶技术制备出水分散纳米杂化改性硅溶胶,并用透射电镜TEM和红外光谱FT-IR对其进行表征和分析,研究了硅烷偶联剂碳链长度及偶联剂用量、溶液pH值对改性硅溶胶稳定性的影响,初步探讨了其在水性涂料、水性纳米罩光防污涂料及砂浆防水中的性能和应用。     

Surface Modification of Nanometer Silica by N, N''''-dicyclohexyl- carbodiimide Mediated Amidation

Nanometer silica has gained ever more attention for its superior properties over conventional micrometer particles and has been widely used as a filler in the manufacture of paints, rubber, plastics and so on1. However it is difficult to get silica mono- dispersed in the matrix due to heavy agglomeration. Surface modification through organic reactions is an efficient way to improve the dispersibility and compatibility with the matrix, thus improving the mechanical properties of the composite…     

Surface Modification of Colloidal Silica by Sulfonation Route for Super-Hydrophilicity

Colloidal silica was chemically modified by a two-step method including an olefin sulfonation route as a preliminary study for super-hydrophilic applications. The hydrophobic vinyl groups were initially bonded chemically to the hydroxylated silica surface using the trichlorosilane coupling agents. The vinyl-terminated silica was then sulfonated by addition reaction with chlorosulfonic acid. The modified silica was investigated using DRIFT, TGA, element analysis, solid-state ²⁹Si- and ¹³C CP-MAS NMR. The vinyl-terminated specimen showed a characteristic IR absorption band at 1600 cm^–1 and a weight loss of approximately 3% starting at 350°C while the ²⁹Si NMR peaks at 70.9 and 79.8 ppm and ¹³C NMR at 136 ppm and 129.8 ppm were assigned to a vinyl group bonded to silica. Elemental analysis of the sulfonated silica indicated the presence of sulfur, carbon and hydrogen. Thermal decomposition in range 150–600°C was due to the presence of sulfonated organics and unreacted vinyl groups while the new signals on ¹³C NMR, which were in the range 70–15 ppm, were assigned to sulfonated carbons.     

Surface Modification of Porous Silica with Bi-thiophene Tripodal Ligand and Aplication to Adsorption of Toxic Metal Cations

The immobilization of a thiophene-based tripodal ligand, with a donor sulfur, on the surface of an epoxide group containing a silica gel phase for the synthesis of a newly functionalized material based on porous silica-bound bi-thiophene tripodal ligand (SGBT) is described. The modified silica surface was characterized by ¹³C NMR of a solid sample, elemental analysis, and infrared spectra. This new material was also studied and evaluated by determination of the surface area using the BET equation, the adsorption and desorption capability using the isotherm of nitrogen and BJH pore sizes, respectively. The target material exhibits good thermal stability as determined by thermogravimetry curves. The synthesized material was utilized in column and batch methods for adsorption of Hg²⁺, Cd²⁺, Pb²⁺, Cu²⁺, Zn²⁺, K⁺, Na⁺, and Li⁺, and the material exhibits an affinity only towards toxic heavy metals.     

SiO2大分子单体的合成

SiO2大分子单体的合成;SiO2;甲苯二异氰酸酯;表面修饰;二氧化硅大分子单体     

Synthesis and Characterization of the Organic Surface Modifications of Monodisperse Colloidal Silica

Monodisperse colloidal silica spheres were prepared from tetraethylorthosilicate in mixtures of water, ammonia and ethanol. The surfaces of the spheres were successfully modified by chemical reaction with silane coupling agents. Several qualitative and quantitative methods were employed to analyse the organic surface modifications. As a result, the surface coverage of silica spheres with silane coupling agents could be calculated using different characterization methods.     

基于硅胶表面修饰的分子印迹技术研究进展

综述;基于硅胶表面修饰的分子印迹技术研究进展