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991.
Atomic Force Microscopy and Scanning Electron Microscopy were used to study shear-induced alignment of alumina and silica nanoparticles in two-component polyurethane clear coatings. 1-D strings of nanoparticles, formed in an extended pearl-necklace fashion were observed near the surfaces of cured films at nanoparticle volume fractions less than 0.05. This alignment is affected by the shear conditions of the application method. When applied by spraying, linear particle strings as long as 5 cm were observed in the direction of shear. Nanoparticle strings were also found, to a lesser extent, when coatings were applied by a drawdown method. The phenomenon was not observed in coatings applied with minimal shear. These particle string formations, in addition to affecting the performance of coatings, may have broader implications in the field of nanomaterials. Our literature searches so far have not uncovered reports of stable, 1-D nanoparticle arrangements with same degree of linearity produced under simple shear with compositions having very low particle loadings. Presented at the 2006 FutureCoat! conference, sponsored by the Federation of Societies for Coatings Technology, in New Orleans, LA, on November 1–3, 2006.  相似文献   
992.
掺杂萘并吡喃的涂料光致变色性能研究   总被引:1,自引:0,他引:1  
柏立岗  谈廷风 《涂料工业》2007,37(10):29-31,36
制备了一种能用太阳光(或紫外光)控制色彩变换的涂料。研究表明,通过光调控开关,将有机光功能材料的信息存储与显示功能在高分子载体(涂料)中得到充分展示。光调控的、智能化的新材料,使色彩变化多样,能丰富人们的生活。  相似文献   
993.
In the current study, a combination of acrylic polyol (AP) and ester polyol (EP) were synthesized and reacted at variable ratios with hexamethylene diisocyanates and isophorone diisocyanates to prepare a transparent two-component polyurethane (PU) coating formulation. The formations of the polyol system, isocyanate system, and the PU systems were confirmed by 1H nuclear magnetic resonance and Fourier-transform infrared spectroscopy. Transparency of the coatings was examined using haze, and gloss measurement, which showed acrylic-ester-polyurethane (aePU-5 and aePU-6) have 91.5% and 91.8% transparency and gloss of 90.3 and 90.7 GU respectively. The thermal properties like Tg and the thermal stability of the coatings were verified using differential scanning calorimetry, and thermogravimetric analysis respectively which was found to increase with increasing EP content and decreasing AP content which may be ascribed to improved compatibility of copolymers, and homogeneity in PU along with enhanced crosslinking density. The degree of adhesion of coating with the substrate was validated from lap-shear, and cross-cut tape test which showed improved performance at AP:EP ratio of 60:40. The coatings were found to exhibit resistance toward pencil hardness with aePU-5 and aePU-6 having the optimum resistance of 9H. The surface morphology and topography were observed under scanning electron microscopy, and atomic force microscopy, respectively. The outcome confirms the higher smoothness of the surfaces subjected to the increase in EP content. The PU system with 40 wt% AP content and 60 wt% EP designated as aePU-5 was found to exhibit optimum performance.  相似文献   
994.
In this work, Bis-(3-triethoxysilylpropyl) tetrasulphane was employed for surface modification of silica, ferrite and kenaf fiber filled natural rubber composites using aqueous solvent deposition, dry blending and integral blend methods. The efficiency of each method and the preferred modification method for improving the mechanical performance of natural rubber composites was assessed. The appearance of the Fourier transform infrared spectroscopy peak around 1088 cm−1 for all types of fillers provided evidence that silane interaction had occurred between the fillers and rubber and the formation of siloxane linkages were quantitatively determined by the crosslink density measurement. The surface treatment by dry method for silica and ferrite fillers showed significant improvement of tensile performance at approximately 67% and 34% compared to those with untreated fillers. For kenaf fiber-filled rubber composites, the surface treatment by aqueous solvent deposition showed the highest tensile improvement of 59% compared to the dry blending and integral blend method.  相似文献   
995.
The modified polypropylene (PP) separators with self‐polymerization of dopamine on the surfaces are prepared by a simple solution‐immersion method to improve the interfacial hydrophilic and discharge performance. The contact angle test and the liquid electrolyte uptake capacity test results show that the wettability and the electrolyte‐retention ability of polydopamine‐modified separator are improved significantly. The robust and thin polydopamine layer on the surface also enhances thermal performance and tensile strength of the modified PP separator certified by DSC and tensile strength tests. The ionic conductivity of the modified PP separator is up to 3.08 mS·cm?1, ~2.5 times of the bare separator. Good discharge capacity retention and C‐rate discharge performance are demonstrated by a 2025 coin half‐cell with the liquid electrolyte‐soaked polydopamine modified PP separator sandwiched between lithium metal anode and LiFePO4 cathode. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40543.  相似文献   
996.
为了研究表面微结构与自抛光的协同防污效果,将具有吸水溶胀能力的微球加入到自抛光树脂中,通过交联反应制备了表面微结构自抛光防污涂层,考察了涂层浸水过程中表面微结构形貌、溶胀、自抛光性能和抑制小球藻附着性能。研究结果表明:涂层自抛光过程中,微结构形貌的变化随微球含量的增加而更加明显;涂层溶胀率与微球的含量正相关,自抛光率与可水解单体含量正相关,但可水解单体含量过大时,涂层溶胀与自抛光成相互制约关系;小球藻附着率随微球含量的增加而增大,随可水解单体含量的增加而下降,当微球分散液质量分数为10%、可水解单体质量分数为40%时,涂层抑制小球藻附着的效果最佳。  相似文献   
997.
包媛  李旭文  徐萍 《涂料工业》2020,50(4):70-75
介绍了水包砂多彩涂料的制备工艺流程,对保护胶的用量和种类、纤维素醚用量和种类、不同类型的乳液、防沉剂的种类进行平行实验。实验结果表明:选用 S482为保护胶,涂料的耐水白性和稳定性好;分散相中疏水改性纤维素醚 HE-10K用量为 0.4%~0.6%、250HBR用量为 0.2%~ 0.6%,连续相中 4% S-482保护胶溶液用量为 25%、HY-1黄原胶用量为 0.025%、TX-100乳液用量为 3%~5%、RS-3799乳液用量为 12%~15%时,所制的水包砂多彩涂料具有强度适中、抗渗色性强、耐水白性好、贮存稳定性好的特点。  相似文献   
998.
在介绍国内汽车涂装的环保、节能减排现状及差距和"绿色涂装"理念(6个高效、10个更少、2个高效、1个更低)的基础上,按汽车涂装工艺推荐了26项成熟的先进适用的绿色涂装工艺技术。  相似文献   
999.
介绍了新型耐高温耐腐蚀涂层材料——陶瓷塑料的性能及性能影响因素。  相似文献   
1000.
全面分析了我国船舶涂料、集装箱涂料、海洋资源开发及装备的防腐涂料涂装体系以及沿岸基础设施建设的防腐蚀保护涂料的现状及发展趋势。  相似文献   
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