溶胶-凝胶法制备透明无机-有机纳米复合硬质薄膜

利用旋覆法通过溶胶－凝胶（Ｓｏｌ－ｇｅｌ）法在有机玻璃（ＰＭＭＡ）表面制备无机－有机硬质薄膜，产品具备致密、透明、耐擦伤等性能．纳米氧化物颗粒在体系中均匀分布，使硬度及耐擦伤性能较有机玻璃均有较大提高．     

基于纳米二氧化硅的防冰疏水涂层的制备及性能研究

采用HTPS(端羟基聚二甲基硅氧烷)和APTES(氨基丙基三乙氧基硅烷)改性纳米SiO_2,并制备了改性纳米SiO_2/氟硅树脂-环氧树脂(M-SR)复合涂料。采用傅里叶变换红外光谱仪和扫描电镜对改性前后纳米SiO_2颗粒,以及M-SR复合涂料的结构和表面微观形貌进行了表征,并通过水接触角、水滴结冰时间和覆冰层的剪切附着强度评估了M-SR复合涂层的防覆冰效果。结果表明,经过HTPS和APTES改性后,纳米SiO_2颗粒表面的亲水基团被HTPS和APTES中低表面能的甲基取代,纳米SiO_2表面能更小,疏水性能更佳。随着改性纳米SiO_2颗粒含量的增加,M-SR复合涂层的疏水性增强,纳米SiO_2颗粒含量为50%的M-SR复合涂层综合性能最优,水接触角168.1°,水滴结冰时间279 s,覆冰剪切粘附强度小于5 kPa,是较为理想的防覆冰材料。     

二氧化硅纳米颗粒/硅树脂复合超疏水功能涂层的制备和性能研究

将二氧化硅纳米颗粒和硅树脂制成混合液,采用喷涂法(spray-coating)制备出了具备超疏水性的复合涂层.研究了二氧化硅、硅树脂不同含量配比对涂层疏水性能的影响,结果表明复合涂层的接触角随二氧化硅含量的增加而增加.在二氧化硅含量大于3%(质量分数)时,涂层显现超疏水性;当二氧化硅含量为3%(质量分数)、硅树脂含量为7%(质量分数)时,涂层与水的接触角达到151.6°,滚动角接近0°.通过扫描电子显微镜(SEM)观察涂层表面的微观结构,发现超疏水性的涂层具备微-纳复合阶层结构,类球状突起粒径在5μm左右,类球状突起上分布纳米团聚颗粒,直径约为50 nm.这种类似荷叶表面的微(纳复合阶层结构,结合硅树脂的低表面能,使得复合涂层具备了超疏水性能.     

面向陶瓷表面自清洁和防覆冰应用的耐候性石墨烯超疏水涂层制备

超疏水涂层应用广泛，尤其在解决陶瓷表面自清洁、防覆冰等方面具有重要的应用价值。本文采用石墨烯与甲基硅树脂为主要原料制备超疏水涂料，结合喷涂和热处理技术在陶瓷基体表面制备了石墨烯超疏水涂层。实验对该涂层的显微结构和基团组成进行测试分析，探究了石墨烯超疏水涂层的自清洁性能和防覆冰功能，并通过长期户外实验，考察涂层的耐候性。结果表明：当甲基硅树脂溶液添加量为150μL、热处理温度为200℃时，制备的石墨烯涂层具备最佳的超疏水性能。采用该超疏水涂层修饰的陶瓷表面，具备优异的自清洁和防覆冰功能，以及长期户外耐候性。     

多面体低聚倍半硅氧烷材料改性硅树脂的研究进展

硅树脂兼具有机材料和无机材料的特点,被广泛应用于电绝缘漆、涂料、粘接剂和塑料等领域,但硅树脂起始分解温度较低,限制了其进一步应用。多面体低聚倍半硅氧烷(POSS)是一类由硅氧骨架组成,具有纳米级三维立体空间结构的杂化分子,其作为添加剂能有效改善硅树脂的力学性能和耐热性能。本文主要介绍了POSS改性硅树脂的不同方法,综述了POSS材料在硅树脂改性领域的研究进展。     

纳米疏水材料的研究现状

论述了对无机有机纳米颗粒进行疏水改性,并喷涂、浸涂至各种基材上形成涂层,将纳米颗粒沉积形成薄膜,对两种纳米疏水材料的研究现状和应用进展进行展望。     

含羟基柔性链段纳米二氧化硅的制备及其对高速列车涂层性能的影响研究

采用两步法对纳米二氧化硅进行有机无机杂化改性,首先通过异氰酸酯的桥接作用,在纳米二氧化硅的表面引入环氧树脂分子,再利用环氧基团的碱式开环反应,形成可参与交联固化的羟基,制备了表面接枝含羟基柔性链段的纳米填料,研究了纳米二氧化硅不同用量对涂层材料力学性能与耐磨性能的影响。结果表明,有机无机杂化改性后的纳米二氧化硅能与有机树脂发生化学反应,改善了无机纳米二氧化硅在涂层中的分散性,提高了有机/无机的界面相容性,从而提高了涂层的韧性和致密性。当改性纳米二氧化硅的添加量为6%时,与添加未改性纳米填料的涂层相比,其耐磨性提高了24%,拉伸强度提高了25%,断裂伸长率提高了50%,涂层的饱和吸水率降低了40%。     

纳米疏水材料的研究现状

论述了对无机有机纳米颗粒进行疏水改性,并喷涂、浸涂至各种基材上形成涂层,将纳米颗粒沉积形成薄膜,对两种纳米疏水材料的研究现状和应用进展进行展望。     

含羟基柔性链段纳米二氧化硅的制备及其对高速列车涂层性能的影响研究

采用两步法对纳米二氧化硅进行有机无机杂化改性,首先通过异氰酸酯的桥接作用,在纳米二氧化硅的表面引入环氧树脂分子,再利用环氧基团的碱式开环反应,形成可参与交联固化的羟基,制备了表面接枝含羟基柔性链段的纳米填料,研究了纳米二氧化硅不同用量对涂层材料力学性能与耐磨性能的影响。结果表明,有机无机杂化改性后的纳米二氧化硅能与有机树脂发生化学反应,改善了无机纳米二氧化硅在涂层中的分散性,提高了有机/无机的界面相容性,从而提高了涂层的韧性和致密性。当改性纳米二氧化硅的添加量为6%时,与添加未改性纳米填料的涂层相比,其耐磨性提高了24%,拉伸强度提高了25%,断裂伸长率提高了50%,涂层的饱和吸水率降低了40%。     

柔性陶瓷复合涂层在油田集输管线防垢中的应用研究

无机微纳米陶瓷粉为填料,加入溶剂、稀释剂、固化剂,涂刷在金属表面可以得到柔性陶瓷复合涂层。通过扫描电子显微镜(SEM和接触角测试表征,研究涂层表面结构与润湿性能的关系。研究表明,涂层表面的乳突结构能够增大水滴角,有效降低材料表面能,减小成垢离子在涂层表面的接触面积。柔性陶瓷复合涂层在油田管道现场挂片实验,展现出良好的防垢效果。     

Mechanical properties and flammability of polycarbonate alloys containing nanosize additives

Different organic–inorganic composite particles [montmorillonite/poly(butyl acrylate) (PBA)/poly(methyl methacrylate) (PMMA), SiO₂/PBA/PMMA, and CaCO₃/PBA/PMMA] were synthesized by emulsion polymerization. Furthermore, polycarbonate (PC) alloys were prepared via the doping of these composite particles into PC with a twin‐screw extruder. The structure, mechanical properties, and flammability of the PC alloys were studied in detail. Although the tensile modulus of PC decreased a little, the flexibility and impact resistance were improved by the addition of these composite particles. This result was attributed to the fact that the composite particles were well dispersed in the PC matrix, with a cocontinuous phase formed between the particles and PC. In addition, the combustion behavior of the PC alloys, compared with that of the pure PC, resulted from a ceramic‐like char that formed on the surface of the PC alloys during burning. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Chemical resistance and cleaning properties of coated glazed surfaces

The effects of sol–gel-derived ceramic titania and zirconia coatings on staining resistance and cleanability of two matt and one glossy glazed tile were characterized. The surfaces were soaked in a weakly alkaline detergent solution in order to imitate the influence of normal household detergents on the surface properties. The soaking caused the water contact angle of the surfaces to decrease and also changes were observed in the average surface roughness. The surfaces were soiled with one color marked and two radiochemically labeled soil mixtures of oils and inorganic or organic particles. Under normal laboratory illumination conditions, the soils consisting of oil and inorganic particles were more easily cleaned from the surfaces than the soil with oil and organic particles. All surfaces soiled with the color marked mixture were also studied under exposure to UV light. The titania coating increased the cleanability and also showed self-cleaning capability after exposure to UV light, whereas exposure to UV increased the soil adherence to the zirconia-coated surfaces.     

SrTiO3 as a new solar reflective pigment on the cooling property of PMMA-ceramic composites

Polymer-ceramic hybridization is an important method for preparing functional materials. Strontium titanate (SrTiO₃, ST), a typical perovskite ceramic, has been widely applied in the electronics industry and photocatalytic fields. However, ST was barely reported to be utilized in cool materials. Herein, ST ceramic, as a solar reflective pigment, was introduced into a polymer matrix to prepare cool material. Specifically, the influences of both weight contents and surface grafting modification about ST on the properties of poly(methyl methacrylate) (PMMA)/ST composites were investigated, which include cooling performance, surface roughness, thermal emissivity, dispersion of particles and mechanical strength. The obtained composites containing 20 wt% unmodified ST possess excellent cooling property due to high thermal emissivity (86.8%, in 8–13 μm) and high solar reflectance (70.7%, in the whole solar band) which increased by 142% than that of pure PMMA resin. Temperature test highlighted that the composites containing 20 wt% unmodified ST was only 26.6 °C, 11.4 °C lower than that of PMMA resin and only 2 °C higher than initial temperature. Moreover, the surface grafting modification of ST by the silane coupling agent was proved to improve the dispersibility of ST in PMMA resin. Both the cooling and mechanical properties of composites containing modified ST particles were further improved. Though the solar reflectance of PMMA/ST composites was lower than that of PMMA/TiO₂ composites, temperature tests showed that the PMMA/ST composites had a similar cooling performance with the PMMA/TiO₂ composites when the content of the ceramic particles were 5.8 v%. This work not only prepared the polymer-ceramic hybrid materials with excellent cooling performance but also expanded the application of ST ceramic in the field of composites.     

Preparation and characterization of photopolymerizable organic–inorganic hybrid materials by the sol-gel method

A series of UV-curable organic–inorganic hybrid materials were prepared by the sol-gel technique and coated onto Plexiglass^® substrate. The effects of the content of EGDMA and the content of the inorganic part on various properties of the coatings, such as tensile strength, hardness, gloss, and cross-cut adhesion, were investigated. It was found that the properties of the coating were improved by the addition of an inorganic part. The thermal properties of the hybrids were enhanced by incorporating silane sol into the organic part. Furthermore, it was found that the coating containing silica had a higher char content at 800 °C than the coating without silica. SEM studies indicated that nanosized (about 50 nm) silica particles were evenly dispersed throughout the organic matrix. A photo-DSC investigation showed that the organic coating polymerized more quickly than the hybrid coating.     

Preparation and characterization of phosphine oxide containing organosilica hybrid coatings by photopolymerization and sol–gel process

A series of UV-cured organic–inorganic hybrid coating materials containing up to 20 wt.% silica were prepared by sol–gel method from tetraethoxy silane (TEOS) which is used as the primary inorganic precursor, and diallylphenylphosphine oxide monomer (DAPPO), aliphatic urethane diacrylate resin (Ebecryl 210) are employed as the source of the organic components. In addition, methacryloxypropyltrimethoxy silane (MAPTMS) was used as both a secondary inorganic source and a silane-coupling agent to improve the compatibility of the organic and inorganic phases. The DAPPO content in all the coating formulations were from 0 to 20 wt.%. The physical and mechanical properties such as gel content, hardness, adhesion, gloss, contact angle as well as tensile strength were measured. These measurements revealed that all the properties of the hybrid coatings improved effectively, in case of adding the sol–gel precursor and DAPPO monomer content in the hybrid systems. The photo-calorimetric-DSC studies showed that the double bond conversion of the hybrid coatings was faster than the coating materials without silica. The thermal stabilities of the UV-cured hybrid materials were investigated by thermogravimetric analysis. The results showed that the addition of sol–gel precursor and DAPPO into the organic network also improves the thermal-oxidative stability of the hybrid coating materials. The surface morphology was also characterized by scanning electron microscopy (SEM). SEM studies indicated that inorganic particles were dispersed homogenously throughout the organic matrix.     

高温防腐涂料与热障防腐涂层技术的研究进展

综述了国内外耐高温防腐有机、无机和有机-无机复合涂料和热障防腐涂层技术的研究与应用的新进展,介绍了有机硅树脂、有机氟树脂、无机硅酸盐基涂料、无机磷酸盐基涂料、陶瓷涂层和搪瓷涂层的发展现状和前景.     

Characterization of antireflective coatings on poly(methyl methacrylate) substrate by different process parameters

The high/low refractive index organic/inorganic antireflective (AR) hybrid polymers were formed using the sol–gel process, in which TiO₂/2‐hydroxyethyl methacrylate (2‐HEMA) (high refractive index hybrid polymer) and SiO₂/2‐HEMA (low refractive index hybrid polymer) two‐layer thin films were formed on a hard coating deposited poly(methyl methacrylate) (HC‐PMMA) substrate by both spin coating and dip coating. The relationship between the process parameters and the optical properties, thickness, porosity, surface morphology, and adhesion was determined. The results show that the reflectance of the two‐layer thin films on HC‐PMMA substrate is less than 0.21% (λ = 550 nm), with good adhesion (5B) and a hardness of up to 4H. In addition, the thickness, porosity, and roughness of the films affect refractive index and the antireflection properties of the AR two‐layered thin film. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Ceramic Surface Reactions and Carbon Retention during Non-Oxidative Binder Removal Al2O3/Poly(methyl methacrylate) at 20°–700°C

Neat poly(methyl methacrylate) (PMMA) thermally decomposes in oxygen-free environments with negligible production of nonvolatile residue. Compacts of α-alumina powder containing PMMA that are fired in a non-oxidative ambient, however, retain appreciable amounts of char. Fourier transform infrared (FTIR) spectroscopy and evolved gas analysis utilizing mass spectral detection were employed to probe the chemical mechanism that initiates the production of organic residue from non-oxidatively fired PMMA/alumina bodies. We find that binding of organic groups to alumina particles is caused by a sponification reaction between either the ester groups of PMMA or thermally evolved PMMA fragments (including MMA) and hydroxyl groups on alumina particle surfaces. Isolated alumina surface hydroxyl groups were found to be much more reactive than mutually hydrogen-bonded alumina surface hydroxyl groups in producing surface-bound organic groups. This surface-carboxylate-forming reaction anchors organic residue to the inorganic surfaces to temperatures above the unzipping temperature of the polymer and leads to retention of organic fragments in the compacts at temperatures where neat PMMA has completely volatilized. Subsequent transformations of these surface-bound organic fragments at high temperatures produce the nonvolatile carbonaceous residues, which are retained in the fired alumina compacts. We demonstrate that unsaturation in the carboxylate side chain plays an important role in this stage of the process in increasing the char yield. We also show that the char yields are proportional to surface carboxylate coverage but that it is difficult to control surface carboxylate coverage by thermal pretreatments of the alumina powders.     

三元硼化物陶瓷涂层的制备及其力学性能研究

笔者采用的是在Q235钢基体表面用固相反应法制备三元硼化物陶瓷涂层,因为固相反应法制备陶瓷消耗的能源少、污染小、工艺简单,相对传统的制备工艺所需成本较低,所以研究固相反应型三元硼化物陶瓷涂层有很高的科学价值和实用价值。笔者采用Fe-B、Mo、Fe、Al、Cr为陶瓷骨料,使用无机粘结剂磷酸二氢铝作为陶瓷涂层的粘结剂来制备三元硼化物陶瓷涂层,对这种制备陶瓷涂层的工艺做基础性的研究。研究主要有:陶瓷涂层配比研究,陶瓷骨料配比,陶瓷骨料与磷酸二氢铝粘结剂最佳配比;固相反应法制备三元硼化物陶瓷涂层工艺:Q235钢基体表面预处理,固化温度,固化工艺等;涂层结构与性能研究:对涂层的致密性、显微组织、相组成、涂层与基体的结合强度、涂层抗热震性能、涂层的耐磨性进行了研究。     

Heat‐resistant hydrophobic–oleophobic coatings

Thermally and chemically durable hydrophobic oleophobic coatings, containing different ceramic particles such as SiO₂, SiC, Al₂O₃, which can be alternative instead of Teflon, have been developed and applied on the aluminum substrates by spin‐coating method. Polyimides, which are high‐thermal resistant heteroaromatic polymers, were synthesized, and fluor oligomers were added to these polymers to obtain hydrophobic–oleophobic properties. After coating, Al surface was subjected to Taber‐abrasion, adhesion, corrosion, and thermal tests. The effects of the particle size of ceramic powders, organic matrix, and heat on the coating material were investigated. Coating material was characterized by FTIR spectrophotometer. Surface properties and thermal resistance of the coating materials were investigated by SEM and TGA analyses. After thermal curing, contact angles of these coatings with H₂O and n‐hexadecane were measured. It was observed that coatings like ceramic particles are more resistant against scratch and abrasion than the other coatings. Also, they are harder than coatings, which do not include ceramic particles. It was seen that coatings, containing Fluorolink D10H, have high‐contact angles with water and n‐hexadecane. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2386–2392, 2006