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31.
Gemini表面活性剂的研究现状及其前景 总被引:1,自引:0,他引:1
Gem in i表面活性剂具有特殊的结构与性质,所以也就具有了独特的用途。本文从合成、应用等方面系统地分析了Gem in i表面活性剂国内外研究现状,重点介绍了国内的最新研究进展,并展望了其发展前景。 相似文献
32.
松香基吉米奇(Gemini)季铵盐的合成与应用 总被引:4,自引:0,他引:4
以天然松香、四甲基乙二胺、环氧氯丙烷为原料,制备出松香基吉米奇(Gem in i)季铵盐,成盐最佳温度80℃,酯化最佳温度140℃。产品可用于阳离子分散松香胶乳化剂、农药增效剂、阳离子沥青乳化剂。 相似文献
33.
34.
中国加入WTO后,中国洗涤用品行业面临着新的机遇与挑战,中国洗涤用品市场将面临更加激烈的竞争。由于环保的呼声越来越高,中国已开始在部分地区禁磷。中国洗涤用品工业将如何发展,其前景如何,专家的看法又如何,就这些问题本刊专访了有关人士。 相似文献
35.
Peter?S.?Piispanen Bj?rn?Hedman Torbj?rn?NorinEmail author 《Journal of surfactants and detergents》2002,5(2):165-168
The syntheses of derivatives of dehydroabietic acid suitable for further manipulation into surfactants are presented. The
compounds are produced at very high yields and purity. They contain several different functional groups, e.g., carboxylic
acid, amine, ester, alcohol, and an aromatic group. The functional groups are useful as the linking unit to the hydrophilic
part in synthesizing surfactants. 相似文献
36.
Robert G. Laughlin 《Journal of the American Oil Chemists' Society》1990,67(11):705-710
Recent phase studies of several surfactant-water systems, using new or refined methods, have revealed significant errors in
earlier phase diagrams. These diagrams had been determined largely using methods based on the isoplethal phase studies principle.
This principle has inherent limitations which do not exist in isothermal methods.
Isothermal nuclear magnetic resonance and refined calorimetric methods have been extensively used in recent surfactant phase
studies. Methods based on the new lyotrope gradient (swelling) principle show great promise as a means of improving the efficiency
and quality of surfactant phase studies. 相似文献
37.
介绍了阳离子双子表面活性剂近年来在新材料制备、抗腐蚀、杀菌、三次采油、织物染整、生物技术及造纸工业等方面的应用。 相似文献
38.
Zhong-Ni Wang Gan-Zuo Li Jian-Hai Mu Wen-Xia Zhang 《Journal of surfactants and detergents》2002,5(4):391-396
The interaction and synergism of some polyoxyethylenated fatty alcohol ether (POE) nonionic surfactants (C12E2, C12E3, C10E5, C10E7, where Cx indicates number of carbon atoms in the chain and Ey indicates number of oxyethylene glycol ethers) with trioxyethylenated dodecyl sulfonate (C12E3S) in mixed monolayer formation at the surface and in mixed micelle formation in aqueous solutions were studied at 25 and
40°C by calculating interaction parameters (βα, βM) from surface tension-concentration data by use of Rosen's equations based on the nonideal solution theory. All the systems
investigated adapt reasonably well to the nonideal model, with negative values of βσ and βM (where M means micelle and σ refers to the air-liquid interface) indicating a favorable interaction between the mixed surfactants.
Either at a monolayer or in a mixed micelle, the attractive interaction becomes stronger when the alkyl chain in the POE surfactant
is longer, i.e., when the POE becomes more hydrophobic. The interaction increases in the order C10E7<C10E5<C12E3, C12E2. For the two C10E
n
(n= 5,7)/C12E3S systems, as temperature increases from 25 to 40°C, the interaction increases in a mixed micelle, but it decreases in a mixed
monolayer. Synergism in mixed micelle formation exists for C12E3S/C10E
n
mixtures when X1
M
, the mole fraction of POE in a mixed micelle, is ≈0.4–0.8, whereas synergism does not occur in the systems of C12E3S/C12E
m
due to the large difference between CMC1 and CMC2, i.e., large |In(C
1
M
/C
2
M
)| value (where CMC=critical micelle concentration). The degree of synergism in mixed micelle formation is temperature independent
and is 0.23, 0.18, and close to zero for C10E5/C12E3S, C10E7/C12E3S, and C12E
m
(m=2,3)/C12E3S systems, respectively. Synergism in surface tension reduction effectiveness occurs in C12E3S/C12E2 and C12E3S/C12E3 systems. The mole fractions of POE in the solution phase are 0.302 and 0.333 for the two mixtures at the point of maximum
synergism. 相似文献
39.
In the ceramic technology the first step to produce sintered bodies is the manufacturing of powders which then are densified. The adhesion mechanisms between the single particles and the agglomerates produced from them determine the densification process. Starting from theoretical considerations adhesion mechanisms, such as solid bridge formation, adhesive bonding and glide-promoting effects, are discussed in principle. Subsequently, the effects of surface-active substances on the densification behaviour of clay-ceramics and oxide-ceramic bodies are discussed. Further, the evaluation of the action of additives to the powder mixtures on the microstructure of the compacts, such as porsity and texture, leads to a compaction equation which describes the transition from the powder pile to a densified green body. 相似文献
40.
Valter Castelvetro Cinzia De Vita Giacomo Giannini Simone Giaiacopi 《应用聚合物科学杂志》2006,102(4):3083-3094
The evolution of the main colloidal parameters in the seeded starved‐feed semi‐continuous emulsion polymerization of butyl methacrylate (BMA) was investigated, with the main purpose of assessing the effectiveness of the semi‐empirical relationship S = K · SS · ΔA/AS as a tool to define the surfactant/monomer feed ratio (∝ K) best suited to achieve a target particle size. In particular, the effect of the type and amount of surfactant [i.e., anionic, sodium dodecyl sulfate (SDS), or nonionic, Brij 58P] added during the semi‐continuous stage was considered. Coagulum formation was never observed under the adopted experimental conditions. To detect the occurrence of secondary nucleation or particle aggregation, or both, the particle size and number of particles, the surface tension and the particle surface coverage ratio were correlated. The best results were obtained with SDS and 0.8 ≤ K ≤ 3. In fact, under the selected experimental conditions, only with SDS did the number of particles remain nearly constant throughout the polymerization at the value defined by the seed latex; the particle size distribution was highly monodisperse, and the final particle diameter closely matched the calculated one (~ 120 nm). The above semi‐empirical relationship based on the adjustable parameter K was validated by running test polymerizations aimed at lattices with well‐defined particle size. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3083–3094, 2006 相似文献