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研究了Gemini表面活性剂中疏水"尾巴"结构对性质的影响,以脱氢松香酸和环氧氯丙烷为原料合成了中间体3-脱氢松香酰氧-2-羟丙基氯,再与四甲基乙二胺反应,得到1种以脱氢松香酰基为疏水链"尾巴"的对称Gemini型双季铵盐阳离子表面活性剂:二氯化-N,N′-二(3-脱氢松香酰氧-2-羟丙基)四甲基乙二胺。在合成工艺条件的基础上,采用IR光谱、MS谱和元素分析测试技术对产物进行了结构确认。结果表明,该产物可降低水的表面张力达34.9 mN/m,临界胶束浓度为1.0×10-4mol/L。表明具有良好疏水性能的2个大"尾巴"使合成的Gemini表面活性剂更易形成胶束,大大提高了表面活性。 相似文献
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应用半经验MNDO量子化学计算方法确定了松香中4种枞酸型树脂酸的优化几何构型及相对能量,据此对该类树脂酸分子的构象及相对稳定性作了分析与预测,并与已知的实验结果作了对比。 相似文献
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松香的主要成份是枞酸型树脂酸,其因共轭双键的存在而易被氧化,大大降低了其附加值。经氢化后的松香具有抗氧性好、脆性小、热稳定性高、颜色浅等特点,因而广泛应用于胶粘剂、合成橡胶、涂料、油黑、造纸、电子、食品等工业部门[1]。采用催化加氢的方法可使枞酸型树脂酸中的共轭双键消除[2]。以枞酸为代表的反应式为:松香催化加氢主要有熔融法[3]和溶剂法[4],所用催化剂主要是Pd和N i。熔融法制氢化松香,当反应温度低于200℃时,枞酸加氢速度较慢,反应不完全。温度升高,氢化松香中枞酸含量显著地减少,但温度高于250℃时,树脂酸脱羧严重,甚至… 相似文献
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Rosin glycerin ester and its bromide were prepared from natural renewable rosin, glycerin and liquid bromine which were first
subjected to an esterification reaction, followed by an addition reaction. Their structures were characterized by an infrared
(IR) spectrum and their thermal resistance was conducted with thermal gravity (TG) and differential scanning calorimetry (DSC).
It showed that the bromide in the rosin glycerin ester decomposed faster than the ester; hence it may be used as fire-resistant
material. 相似文献
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Jifu Wang Kejian Yao Andrew L. Korich Shigeng Li Shuguo Ma Harry J. Ploehn Peter M. Iovine Chunpeng Wang Fuxiang Chu Chuanbing Tang 《Journal of polymer science. Part A, Polymer chemistry》2011,49(17):3728-3738
Rosin polymer–grafted lignin composites were prepared via “grafting from” atom transfer radical polymerization (ATRP) with the aid of 2‐bromoisobutyryl ester‐modified lignin as macroinitiators. Three different monomers derived from dehydroabietic acid (DA) were used for execution of grafting from ATRP, while DA was separately attached onto lignin by a simple esterification reaction. Kinetic studies indicated controlled and “living” characteristics of all monomer polymerizations. Thermal studies indicated that rosin polymer–grafted lignin composites exhibited glass transition temperatures in a broad temperature range from ~20 to 100°C. The grafting of both DA and rosin polymers significantly enhanced hydrophobicity of lignin. Static contact angle measurement of water droplets showed ~90° for all these rosin modified lignin composites. X‐ray photoelectron spectroscopy demonstrated that the surface of rosin–lignin composites was dominated with chemical compositions originating from the hydrocarbon rich rosin moiety. The impartation of hydrophobicity of rosin into lignin provided excellent water resistance of this class of renewable polymers, as all rosin‐modified lignin composites showed water uptake below 1.0 wt %. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
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Functions of the polyamines in neutral rosin sizing were investigated using X-ray photoelectron spectroscopy(XPS) and laser diffraction particle analysis. The polyamine with a higher charge density and a smaller unite size could retainmore rosin and cover larger fiber surfaces. The XPS spectra demonstrated that polyallylamine.(PAAm) and polyvinylamine(PVAm) could react with a rosin size to form a-OC-N-CO-structure, but polydimethylamino ethyl methacrylate(PDMAEMA) could not, The formation of this structure may be a key step for effective sizing. 相似文献
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聚合松香中锌含量的火焰原子吸收法直接测试研究 总被引:4,自引:0,他引:4
利用95%乙醇作溶剂,采用火焰原子吸收法直接测定聚合松香中的锌含量,因内未见类似报道,此方法非常适合在林化企业中推广使用。 相似文献