A correlation for the estimation of critical micellization concentrations and temperatures of polyols in aqueous solutions

An empirical correlation is presented for the estimation of critical micellization concentrations (CMC) and critical micellization temperatures (CMT) for poly(ethylene oxide)-block-poly(propylene oxide)-block-poly(ethylene oxide) copolymers in aqueous solutions. The CMC and CMT are expressed as a function of the polyol molecular weight, composition, and temperature (for CMC determination) or concentration (in the case of CMT). The correlation was developed from experimental CMT data for a set of 12 polyols that covered a wide range of molecular weights (2900–14600) and poly(ethylene oxide) contents (30–80 wt%) and is based on a simple expression for the standard free energy of micellization. Such a correlation should be useful to practitioners of the field as it allows easy prediction of CMC and CMT for a wide range of polyols with a minimal number of input parameters.     

Glucamine-based gemini surfactants II: Gemini surfactants from long-chain <Emphasis Type="Italic">N</Emphasis>-alkyl glucamines and epoxy resins

Gemini surfactants were synthesized by reaction of long-chain N-alkyl glucamines with epoxy resins. Analogous to the synthesis of gemini surfactns from long-chain N-alkyl glucamines and α, ω-diepoxides (1), the reaction in methanol at 70°C could be used to convert the starting materials selectively and almost quantitatively. N-Octyl glucamine, N-decyl glucamine, and N-dodecyl glucamine were combined with several epoxy resins, mainly technical glycidyl ethers of diols. Syntheses involving equimolar amounts of amine resulted in quantitative conversion of the epoxy resins, and epoxide and products could be isolated quantitatively by removing the solvent. Gemini surfactants having hydrophobic or hydrophilic spacers were preparared according to their structures and the hydrophilic properties of the epoxy resin. Surface tensions were measured, and foaming propertiers were examined to characterize surface-active properties of these surfactants. The more hydrophilic products were of particularly high surface activity. Tensiometric studies showed a reduction of surface tension to 30–34 mN/m and critical micelle concentrations in the range of 2–35 mg/L. Comparison of gemini surfactants from long-chain N-alkyl glucamines and diepoxides of α,ω-diolefins (chain lengths: C₈, C₉, C₁₀, and C₁₄) with those based on epoxy resins showed similar or lower surface activities using hydrophobic epoxy resins and much better surface-active properties using hydrophilic epoxy resins (e.g., based on glycerol). This, together with the easier availability, makes the epoxy resin-based products interesting surfactants. Products having very good surface-active properties are available, especially using glycidyl ether of aliphatic diols or glycerol.     

十六烷基三甲基溴化铵对化学镀Co-Ni-P的影响

通过正交试验得到化学镀Co-Ni-P的优化基础配方(g.L-1)和施镀条件:CoSO4.7H2O为16、NiSO4.6H2O为9、NaH2PO2.H2O为30、Na3C6H5O7.2H2O为60、(NH4)2SO4为70,于pH=10、80℃施镀1 h;研究了阳离子表面活性剂十六烷基三甲基溴化铵对Co-Ni-P镀层成分以及镀层与基体结合力的影响。实验结果表明,在优化的基础配方中加入30 mg.L-1的十六烷基三甲基溴化铵,镀液稳定性好,沉积速率加快,镀层表面光亮,镀层与基体的结合力增强,镀层中钴含量增加,镍、磷含量降低,镀层的性能得到了很大的改善。     

Surface activity and solubilization of a novel series of functional polyurethane surfactants

Functional polyurethane surfactants (di‐block and tri‐block) were synthesized by addition polymerization of 2,4‐toluenediisocyanate with poly(propylene oxide) and monoallyl‐end‐capped poly(ethylene oxide). The chemical structure of the polyurethane surfactants was confirmed by Fourier transform infrared and ¹H NMR spectroscopy. These polymeric surfactants were found to have excellent surface activity. The lowest surface tension of polyurethane surfactant aqueous solutions could be reduced to 37.6 mN m^?1. All the polyurethane surfactants synthesized had low critical micelle concentrations and could reduce the surface tension even at very low concentration levels (10^?6–10^?5 mol L^?1). The solubilization of toluene in micelles of the synthesized polyurethane surfactants was studied using UV‐visible spectroscopy, and the results showed that they all exhibited good solubilization capacity. Possible solubilization positions of toluene in the micelles are conjectured. Copyright © 2006 Society of Chemical Industry     

双子表面活性剂合成及在酒精废液处理中应用

合成了4种碳链长度的酯基阳离子双子表面活性剂,并作为絮凝剂对干法工艺处理的玉米酒精糟废液进行了絮凝处理实验。絮凝后对废液的透光率及COD进行了测定,考察了在不调节pH值及室温条件下与双子表面活性剂、淀粉阳离子、壳聚糖阳离子对比絮凝处理效果,双阳离子表面活性剂好于淀粉阳离子、壳聚糖阳离子的絮凝能力;同时考察了酯基阳离子双子表面活性剂碳链长度对絮凝效果的影响,碳链长度对COD去除率的高低顺序为C14>C16>C12>C10。实现了不用碱中和废液而直接进行絮凝处理的工艺改造。     

非离子表面活性剂烷基多苷的合成和应用

烷基多苷（APG）是葡萄糖（或淀粉）与天然脂肪醇在催化剂作用下缩合得到的一种非离子表面活性剂。APG具有优良的表面性能和环境相容性,已经成为新型的绿色表面活性剂,成为近年来的研究热点。对近年来APG的合成方法及其在诸多领域的应用进行了综述。     

季铵盐型阳离子瓜尔胶的制备

以瓜尔胶为原料,3-氯-2-羟丙基三甲基氯化铵为醚化剂,氢氧化钠为催化剂,乙醇为溶剂,制备了季铵盐型阳离子瓜尔胶,考察了乙醇浓度、醚化剂用量、pH值、反应温度、反应时间对季铵盐型阳离子瓜尔胶取代度和反应效率的影响,得出较佳制备条件为:乙醇质量分数为85%,pH11.0,反应温度70℃,反应时间4h,在较佳条件和醚化剂与瓜尔胶质量比为7∶100的条件下,阳离子瓜尔胶取代度为0.1651,反应效率86.79%.     

阳离子染料在D5反相微乳体系中的染色性能研究

分析阳离子染料在D5反相微乳体系中染色的可行性,确立阳离子染料在D5反相微乳体系中上染腈纶织物的工艺,并探讨入染前织物带液率、反相微乳液含水量对染色性能的影响。实验结果表明:腈纶织物在温度为60℃、pH值为4.5~5的水中进行预处理后,以一定带液率入染反相微乳体系的方法可行;优化的阳离子染料在D5反相微乳体系中的染色工艺为:染色温度85℃、染色时间20 min、浴比1∶10;研究中还发现入染前织物带液率的高低对织物得色深度有较大影响,随着带液率的增加,染色K/S值先增加后减少;反相微乳体系的含水量对织物的得色深度无明显影响。     

Activity and stability ofPenicillium cyclopium lipase in surfactant and detergent solutions

Activity and stability of an alkaline lipase fromPenicillium cyclopium var.album (PG 37) were studied in surfactant and detergent solutions. Three anionic surfactants [Na salts of C₁₂SO₄ ^? (sodium dodecyl sulfate), C₁₂ØSO₃/^? (linear alkyl benzene sulfonate), and C₁₁COO^? (laurate)] and four homologous series of nonionic surfactants of C_12–15 polyoxethylenated fatty alcohols (AEO₃, AEO₅, AEO₇, and AEO₉) were evaluated. At a concentration range of 3.2–40 μM, sodium dodecyl sulfate and laurate stimulated the activity of PG 37 lipase. At concentrations greater than 5.6 μM, linear alkylbenzene sulfonate inhibited PG 37 lipase activity. Nonionic surfactants, AEO₅ and AEO₇, in the concentration range of 0.25–20 mM, enhanced and stabilized the activity of PG 37 lipase. The presence of PG 37 lipase in detergent formulaton improved detergency ～20%. The mechanism of inhibition of the lipolytic activity of PG 37 lipase is proposed to be partly due to the formation of inactive (BR)_n-E complex between the hydrophobic moiety of the surfactants and the surface of the lipase. Conversely, formation of a soluble (RB)_n-E complex between the hydrophilic group of the surfactant and lipase may account for the increased lipolytic activity of PG 37 lipase.     

Living cationic random copolymerization of β-pinene and isobutylene with 1-phenylethyl chloride/TiCl4/Ti(OiPr)4/nBu4NCl

The first example of living cationic random copolymerization of β-pinene and isobutylene was achieved with 1-phenylethyl chloride/TiCl₄/Ti(OiPr)₄/nBu₄NCl (TiCl₄/Ti(OiPr)₄ mole ratio: 3/1) initiating system in CH₂Cl₂ at −40 °C. β-Pinene and isobutylene was consumed at almost the same rate, suggesting that the two monomers exhibit almost equal reactivity. At any monomer feed ratio, the number-average molecular weight (M_n) of the copolymers increased in direct proportion to the total monomer conversion, and the molecular weight distribution was relatively narrow (M_w/M_n=1.1-1.2) throughout the reaction. The reactivity ratios determined by the Kelen-Tüdõs method were rβ-pinene=1.1 and r_isobutylene=0.89, which indicated that the composition of copolymer is approximately identical to the monomer feed ratio. The analysis of the structure and sequence distribution of the copolymers by ¹H NMR spectroscopy further confirmed that perfectly random copolymers were obtained by this living cationic polymerization system. The glass transition temperatures of the copolymers obtained with varying monomer compositions were also determined by DSC method.