气相法白炭黑生产技术的研究

本文介绍了气相法白炭黑的制备原理与生产工艺,以及在生产过程中的技术难题.     

Effect of Fumed Silica Nanoparticles on the Gas Permeation Properties of Substituted Polyacetylene Membranes

Summary The gas permeability of three substituted polyacetylenes, poly(1-chloro-2-phenylacetylene) (PClPA), poly[1-phenyl-2-(4-trimethylsilyl)phenylacetylene] (PTMSDPA), and poly[1-(trimethylsilyl)-1-propyne] (PTMSP), increased systematically with increasing content of nonporous fumed silica (FS) nanoparticles. For instance, the oxygen permeability coefficient (PO₂) of PClPA containing 30 wt % FS was 86 barrers, which was 10 times higher than that of the unfilled polymer (PO₂=8.6 barrers). The extent of permeability increase with the addition of FS was smaller when the permeability of the original polymer was higher. The order of the permeability increase in FS-filled polymers was as follows: PClPA > PTMSDPA > PTMSP. The addition of FS resulted in the decrease of O₂/N₂ permselectivity of these polymers. The H₂/CH₄ permselectivity largely decreased with increasing FS content in PClPA, while it hardly changed with FS loading in PTMSP. The gas solubility of PClPA was practically independent of FS content, and the increase in gas permeability in filled PClPA resulted from an increase in diffusivity with the addition of FS.     

气相法白炭黑生产技术的研究

本文介绍了气相法白炭黑的制备原理与生产工艺,以及在生产过程中的技术难题。     

气相二氧化硅和胶体电池

通过对气相二氧化硅本身的特性和气相二氧化硅成胶性能的分析,提出优异的触变性能是气相二氧化硅用于胶体电池的关键因素,也是未来胶体发展的方向。使用优质气相二氧化硅,配合完善的电池组件设计和选择,可以保证较高的胶体电池气体再化合效率,也使得胶体电解液不易干涸,这样的胶体电池才会有着较长的循环寿命。     

气相二氧化硅的表面改性

简要介绍了气相二氧化硅的表面改性、改性原理、改性工艺、常用改性剂以及改性气相二氧化硅的应用。概述了我国气相二氧化硅工业的发展现状。     

Particle Sizes of Fumed Silica

Fumed silica is a synthetic amorphous silicon dioxide produced by burning silicon tetrachloride in an oxygen-hydrogen flame. Surface areas range from 50–400 m²/g. Using particle sizing techniques, fumed silica shows micron sized particles leading to surface areas markedly lower than expected. Fumed silica appears as a fluffy solid with bulk densities down to 0.03 g/cm³, being invariant over the wide range of surface areas. Attempts to relate the variation of the surface area directly to the performance of fumed silica in technical applications, such as its thickening efficiency in fluids, mainly fail and remain ambiguous.     

气相法二氧化硅的表面改性

以气相法二氧化硅为原料,六甲基二硅氮烷为改性剂,采用干法工艺对气相法二氧化硅表面进行改性,探讨了六甲基二硅氮烷用量、反应温度、反应时间对气相法二氧化硅表面改性效果的影响。结果表明,当六甲基二硅氮烷用量为气相法二氧化硅质量的25%、反应温度为150℃、反应时间为40 min时,二氧化硅表面的硅羟基数量最少,比改性前减少97%。     

气相法白炭黑的表面改性

综述了近年来气相法白炭黑表面改性的研究成果和工业化技术。     

合成条件对气相法白炭黑性能的影响

以甲基三氯硅烷、氢气、空气为原料,制备气相法白炭黑。考察了原料配比、骤冷介质温度、合成炉温度、原料气速对白炭黑的比表面积、平均粒径的影响。结果表明：甲基三氯硅烷、氢气的量之比与白炭黑的比表面积成反比;合成炉温、骤冷介质温度与白炭黑的比表面积、平均粒径成反比;原料气速与白炭黑的比表面积成正比,与平均粒径成反比。较佳工艺为：甲基三氯硅烷、氢气与空气的量之比为0.33∶0.47∶1,冷却介质温度80～90℃,炉温800～850℃,气体流速5～6 m/s。     

气相法白炭黑的市场分析

简述了世界气相法白炭黑生产厂的生产能力、国内外差距和国内需求预测。     

Optical and Mechanical Properties of Nanocomposite Films Based on Polymethyl Methacrylate (PMMA) and Fumed Silica Nanoparticles

Nanocomposite polymer films are prepared by using ultrasonic spray deposition (USD) technique through mixing polymethyl methacrylate as matrix and fumed silica nanoparticles as second phase in dimethyl carbonate solvent. Annealing procedure improves the film uniformity and optical transmission. The addition of fumed silica nanoparticles impedes the transmission of the electrolyte films due to agglomeration of fumed silica nanoparticles. Fortunately, adding surfactant, cetyltrimethylammonium bromide, disperses the fumed silica nanoparticles and retrieves the optical transmission of nanocomposite polymer films to around 90%. The hardness and elastic modulus of the nanocomposite polymer films are better than the commercial bulk. The USD deposited nanocomposite polymer film comprises of PMMA and fumed silica nanoparticles is a promising candidate of solid-state electrolyte for EC windows application. POLYM. ENG. SCI., 60:553–557, 2020. © 2019 Society of Plastics Engineers     

气相法白炭黑在涂料中的应用

综述了气相法白炭黑的特性及其在涂料中应用的关键技术，并提出了发展建议。     

Reaction of Ammonia with Fumed Silica

The reaction between fumed silica and ammonia has been studied between 600° and 1200°C. Up to 24 wt% nitrogen can be introduced into vitreous silica by adjusting the partial pressure of ammonia, temperature, and reaction time. The experiments show that the amount of nitrogen incorporated into silica has a linear dependence on the partial pressure of ammonia and a square root dependence on the reaction time. The activation energy for the reaction was found to be 76.0 kJ/mol. The nitrided powders as well as several hotpressed samples were crystallized at 1550° to 1650°C. Silica glasses containing 0 to 1 wt% nitrogen crystallize to cristobalite. Glasses containing 2 to 10 wt% nitrogen are stable against devitrification in nitrogen, even at 1650°C. Glasses with 12 to 28 wt% nitrogen crystallize to fine-grained Si₂N₂O with residual glass.     

气相法二氧化硅在硅橡胶中的应用

介绍了气相法二氧化硅在硅橡胶中的用量对其拉伸强度、伸长率及硬度的影响。此外,分析了硫化后产生气泡的各种原因。     

气相二氧化硅的制备方法及其特性

简述了气相二氧化硅的发展情况和制备方法,介绍了气相二氧化硅的特性、标准及其相关表征方法。     

气相二氧化硅对防污涂料流变性的影响研究

通过曲线对比法与改变E51环氧树脂涂料中H18气相二氧化硅的比例,探究防污涂料的流变性。研究表明H18气相二氧化硅的量是E51环氧树脂2%~8%为最优比例范围,其中比例为5%的环氧树脂涂料配方是在最优比例范围内的最佳添加量。比例为5%的环氧树脂涂料流变性能最好,具有优越的增稠性和触变性。     

SiO_2复合磁性纳米粒子的合成及表面性质的研究

采用溶胶凝胶法合成具有快速磁场响应能力的SiO2复合磁性纳米粒子。用表面电位仪研究了不同包覆层厚度对粒子表面性质的影响。用AFM对粒子的表面形貌进行了表征。并考察了不同SiO2包覆层厚度粒子的抗酸性。结果表明生长3层SiO2后复合粒子的表面完全被SiO2所包覆,粒子具有高的磁含量和快速的磁场响应能力,并具有高的抗酸性。     

气相法白炭黑在消泡剂中的应用

论述了气相法白炭黑的结构特点及在消泡剂中的作用,表明比表面积为200～380m2/g的气相法白炭黑具有最佳应用效果。接着,讲述了它的应用特点、配比和应用体系。     

气相法白炭黑的研究进展

概述了气相法白炭黑的制备、结构与性能，重点介绍了气相法白炭黑的改性方法以及在高分子材料方面的应用进展，并展望了气相法白炭黑的应用前景。