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991.
992.
高黏度苯丙乳液的制备 总被引:2,自引:0,他引:2
为了制备高性能的苯丙乳液,研究了乳化剂、助剂DZ-1及丙烯酸对苯丙乳液黏度及触变指数等性能的影响。研究结果表明:乳化剂用量低反应生成的凝聚物较多,用量大乳液的气泡较多。乳液的黏度和触变指数随DZ—1用置增大而大幅度提高。乳液黏度随丙烯酸用量的增加而提高,但用量超过3%后,耐水性能变差。乳化剂用量为1.0%,DZ-1用量为4.5%,酸用量为3.0%时合成的苯丙乳液黏度和触变指数较高。用该苯丙乳液配制的涂料黏度高、触变性好,耐擦洗及耐水性好,综合性能优良。 相似文献
993.
994.
The copolymer of polyacrylate/polysiloxane for vibration damping materials was synthesized through emulsion polymerization. The effects of the amount of methyl methaerylate (MMA),polysiloxane containing vinyl, initiator and emulsifier on the conversion, stability of polyacrylate/polysiloxane emulsion were discussed when the emulsion was prepared by pre-emulsifying half continuous method. The graft copolymer has good vibration damping performance. The widest glass transition region of the copolymer spans 100℃, and the highest value of tan8 reached 2.0. The glass transition of the samples was examined by dynamic mechanical analysis (DMA). The vibration damping performance of the graft copolymer was affected by the amount of poly-vinyl dimethylsiloxane (PVMS). 相似文献
995.
Sánchez-García JA Ortega A Barceló-Santana FH Palacios-Alquisira J 《International journal of molecular sciences》2010,11(10):3906-3921
Maxillofacial prostheses is a dental medicine specialty aimed at restoring anatomical facial defects caused by cancer, trauma or congenital malformations through an artificial device, which is commonly attached to the skin with the help of an adhesive. The purpose of our research was to develop a pressure-sensitive adhesive (PSA) based on acrylic monomers, characterizing and determining its drying kinetics, that is to say the time it takes to lose 50 to 90% of its moisture. The adhesive synthesis was realized by means of emulsion polymerization; the composition of formulations was: (AA-MMA-EA) and (AA-MMA-2EHA) with different molar ratios. The formulation based on (AA-MMA-2EHA) with 50 w% of solids, presented good adhesive properties such as tack, bond strength, and short drying time. We propose this formulation as a PSA, because it offers an alternative for systemically compromised patients, by less irritation compared to organic solvent-based adhesives. 相似文献
996.
The vacuum residual from Iranian Light crude oil are separated into a series of 16 narrow fractions according to the molecular weight by the supercritical fluid extraction and fractional (SFEF) technology. The chemical element and the UV spectrum of each fraction are analyzed. The effects of several factors on the interfacial tension are investigated, which are the fraction concentration in oil phase, the ratio of oil component, the salts dissolved in the water phase and the pH value. The interfacial tension decreases rapidly as the concentration of the residual fraction in the oil increases, showing a higher interfacial activity of the fraction. The interfacial tension changes, as the amount of absorption or the state of the fractions in the interface changes resulting from different ratios of oil, different kinds or concentrations of salts in water, and different pH values. It is concluded that the intrfacial tension changes regularly, corresponding to the regular molecular parameters of the vacuum residual fractions. 相似文献
997.
998.
环氧树脂拥有诸多优异的性能,被广泛应用于各领域,然而溶剂型环氧树脂越来越难以满足市场对于绿色环保的要求,故寻求将环氧树脂水性化显得颇为关键。详细介绍了机械法、相反转法、化学改性法和固化剂乳化法等水性环氧树脂乳液的制备方法,系统阐述了各种方法的原理和流程,分析总结了影响水性环氧树脂乳液性能的重要因素,详尽地叙述了不同制备方法的优点和缺点,并对其优化和改进方向进行了展望。综述了国内外环氧树脂水性化的最新研究进展,指出了筛选生产配方、优化工艺流程以及有计划地功能性改性等是水性环氧树脂今后的发展趋势。 相似文献
999.
采用Span-80为乳化剂,白油为分散介质,(NH4)2S2O8-Na2SO3为引发剂,研究了丙烯酰胺(AM)与2-丙烯酰胺基-2-甲基丙磺酸(AMPS)的反相乳液共聚反应,合成出了高相对分子质量的共聚物。讨论了引发剂用量、乳化剂用量、水油比、单体浓度等因素对共聚物相对分子质量的影响。引发剂用量为单体质量的0.2‰,乳化剂为油相的6.7%,水油比为1:1.5,单体浓度为37.5%时可获得高相对分子质量的共聚物,且聚合反应平稳易控制。 相似文献
1000.
A. G. Anshits N. N. Anshits A. A. Deribas S. M. Karakhanov N. S. Kasatkina A. V. Plastinin A. Yu. Reshetnyak V. V. Sil'vestrov 《Combustion, Explosion, and Shock Waves》2005,41(5):591-598
The detonation velocity of an emulsion explosive containing hollow alumosilicate microspheres (cenospheres) as the sensitizer
is measured. The size of the microspheres is 50–250 μm. The relations between the detonation velocity and the charge density
and diameter are compared for emulsion explosives containing cenospheres or glass microballoons as the sensitizer. It is shown
that for a 55 mm diameter charge, the maximum detonation velocity of the composition with cenospheres of size 70–100 μm is
5.5–5.6 km/sec, as well as for 3M glass microballoons. The critical diameter for the emulsion explosive with cenosphere is
1.5–2 times larger than that for the emulsion explosive with glass microballoons and is 35–40 mm.
__________
Translated from Fizika Goreniya i Vzryva, Vol. 41, No. 5, pp. 119–127, September–October, 2005. 相似文献