季铵盐双子表面活性剂性能研究

本文测定了四种双子表面活性剂（C12H25（CH3）2N＋（CH2）1N（CH3）2CaH2w＋1和C12H25（CH3）2NCH2CH2OCH2CH2N＋（CH3）2CaH2m＋1（分别记为C12-4-Ca和C12-CH2CH2OCH2CH2-Cm,m=12,18））的表面活性、乳化性能,并计算了表面过剩吸附量（Гmax）和单分予吸附面积（Amia）。结果表咧,合成的删种表面活性剂的临界胶束浓度（cmc）、相应的表面张力（γcmc）、Гmax和Amin基本相差不大。对称的双子表面活性剂的乳化性能优于非对称双子表面活性剂;具有刚性连接基团的乳化性能优于具有柔性连接拱团的双子表面活性剂。并考察了四种表面活性剂对28种植物常见致病菌的抑菌活性。     

N-甲基戊胺的合成

N-甲基戊胺是合成双膦酸盐类药物埃本膦酸钠的重要中间体 ,美国专利合成采用催化氢化法 (收率 49% )。我们以德科尔 -福斯特 ( Decker-Forster)一级胺烷基化法合成 ,方法简便易行 ,收率好。合成路线如下 :CHO +CH3( CH2 ) 4NH2- H2 OCH =N -CH2 ( CH2 ) 3CH3(CH3) 2 SO4C6 H6CH =N+CH3-CH2 ( CH2 ) 3CH3 .CH3SO3- 2 H2 OCHO+CH3OH+CH3( CH2 ) 4N+ H2 CH3· SO3H-2 Na OHCH3( CH2 ) 4NHCH3+Na SO4+2 H2 O　　在 1 L三口瓶中加入 1 0 0 m L无水苯、5 7.8m L( 0 .5 mol)正戊胺和 61 m L( 0 .6mol)苯甲醛 ,加…     

一种阳离子型氟表面活性剂的合成及性能研究

以全氟辛基碘乙烷(C8F17CH2CH2I)为原料,通过格氏反应,得到全氟辛基丙酸(C8F17CH2CH2COOH),进而通过酰氯化、酰胺化和季铵化等多步反应得到一种阳离子型氟表面活性剂C8F17(CH2)2CONH(CH2)3N+(CH3)3I-,用IR,1HNMR和19FNMR对其结构进行了表征。测试了其水溶液及其0.1 mol/L Na Cl水溶液的表面张力、在石蜡表面的接触角以及泡沫性能。结果表明,该氟表面活性剂在室温下具有极高的表面活性,且其泡沫性能及润湿性与传统碳氢阳离子表面活性剂C12H25N+(CH3)3Cl-相比,均更为优异。     

化学镀金液

化学镀金液包括一种水溶性金化合物、配位剂、一种醛类化合物和R1-NH-C2H4-NH-R2或（CH2-NH-C2H4-NH-CH2）N-R1胺类化合物。R1至R4表示-OH,-CH3,-CH2OH,-C2H4OH,-CH2N（CH3）2,-CH2NH（CH2OH）,-CH2NH（C2H4OH）,-C2H4NH（CH2OH）,-C2H4NH（C2H4OH）,     

N-[γ-(二烷基氨基)烷基]全氟辛基磺酰胺类阳离子氟表面活性剂的合成及性质研究

以全氟辛基磺酰氟(C8F17SO2F)和N,N-二烷基氨基烷基二胺[NH2(CH2)nNR2(n = 2, 3; R = -CH3, -CH2CH3)]为原料,合成了四种N-[γ-(二烷基氨基)烷基]全氟辛基磺酰胺[C8F17SO2NH(CH2)nNR2],然后用盐酸酸化和用碘甲烷季铵化分别得到相应的四种盐酸盐[C8F17SO2NH(CH2)nN+HR2Cl-]和四种季铵盐[C8F17SO2NH(CH2)nN+R2(CH3)I-]。研究了这些阳离子型氟表面活性剂在水中的溶解性和表面活性,探讨了中间基团（碳氢间隔基）长度和亲水头基大小对该类阳离子氟表面活性剂性能的影响。结果表明适度改变中间碳氢间隔基长度和亲水头基大小对该类阳离子氟表面活性剂的溶解性影响较大,但对其表面活性的影响不很明显,可归因于这类氟表面活性剂的氟碳链的疏水效应太强,掩盖了中间碳氢间隔基长度和亲水头基大小对其疏水性的影响。它们的细微差别可以从溶解性、溶液表面的吸附状态、空间位阻和电荷密度角度解释。     

长链酰胺基磺酸盐型双子表面活性剂的合成及性能研究

以二聚酸和N-甲基牛磺酸钠为原料,经酰氯化和Schotten-Baumann缩合反应合成了一种磺酸盐型双子表面活性剂,并对其相关性能进行了表征。结果表明,通过正交试验获得的磺酸盐型双子表面活性剂C34H66(CON(CH3)CH2CH2SO3Na)2的优化合成条件为:反应温度15℃,反应时间5 h,碱质量分数40%,n(N-甲基牛磺酸钠)∶n(二聚酸酰氯)=2.3∶1。合成的C34H66(CON(CH3)CH2CH2SO3Na)2具有更高的表面活性,其γcmc和cmc分别为30.4 mN·m-1和3.55×10-4mol·L-1。泡沫性能分析表明其具有良好的起泡性和稳泡性,水溶液的泡沫高度和半衰期分别是传统表面活性剂的1.3~3.2倍和12~33倍。     

改性累托石对苯酚和铬的吸附等温线及分形维数

用十二烷基二甲基苄基氯化铵[C12H25（CH3）2（C6H5-CH2）NCI,1227]、十六烷基三甲基溴化铵[C16H33（CH3）3NBr,1631]、十八烷基三甲基溴化铵[C18H37（CH3）3 NBr,1831]3种表面活性剂改性天然黏土累托石（rectorite,REC）,得到3种有机改性累托石：1227-REC,1631-REC和1831-REC。用3种有机改性累托石对水溶液中有机物苯酚和无机重金属离子Cr（VI）的吸附实验,对比了它们的吸附等温线及相应的分形模型。实验结果表明：改性REC对苯酚和Cr（VI）的吸附作用分别是由阴阳离子静电吸引和表面配位反应所引起的。吸附剂的“吸附活性位”的分形维数计算表明：1227-REC和1631-REC对苯酚的分形维数分别是2．85,2．91;1227REC,1631-REC和1831REC对Cr（VI）的分形维数分别是2．65,2．86和2．73。     

支链烷基苯磺酸钠的表征及表面性质的测定

为了研究支链烷基苯磺酸钠的构效关系,以苯为初始原料经酰化、格氏反应、氢化还原、磺化中和等4步合成了4种支链烷基苯磺酸钠。支链总碳原子数为16,苯环连接位置分别在支链的2,4,6和8位。它们的结构分别为:(A)CH3(CH2)13CH(CH3)C6H4SO3Na;(B)CH3(CH2)11CH(C3H7)C6H4SO3Na;(C)CH3(CH2)9CH(C5H11)C6H4SO3Na;(D)CH3(CH2)7CH(C7H15)C6H4SO3Na。经核磁和红外光谱确定了化合物的结构,用两相滴定方法确定了产物中烷基苯磺酸钠的质量分数均大于99%。用Wilhelmy-Plate法测定了4种支链烷基苯磺酸钠在30℃下的临界胶束浓度CMC(mmol/L)以及临界胶束浓度下的表面张力γCMC(mN/m)。CMC和γCMC值分别为:(A)0 112,35 96;(B)0 232,35 05;(C)0 420,33 86;(D)0 708,31 47。根据Gibbs吸附公式求出饱和吸附量Γm、饱和吸附面积Am以及表面压πCMC。发现随着苯环在烷基链上连接位置由2变化到8,CMC增大,γCMC降低。采用电导法测定了4种支链烷基苯磺酸钠的临界胶束浓度,其结果与表面张力法的测定结果一致。采用两种基于辛醇/水分配系数的方法预测了4种表面活性剂的CMC,结果表明,考虑了支链化的CMC与实验结果符合较好。     

高碳链正负离子表面活性剂复配溶液的表面物理化学性质研究

研究了负离子表面活性剂C12SNa同正离子表面活性剂（C18H37）2N（CH3）3Cl、C16H33N（CH3）3Cl复配溶液的表面物理化学性质，结果表明复配液具有比单一表面活性剂更高的表面活性，且无论正负离子表面活性剂复配比例如何，表面的吸附量与1:1复配液吸附量相似，即吸附量R^ 同R^-比例为1:1左右。     

两性表面活性剂吡啶烷氧基磺酸盐的合成

初步合成出2种具有C5H5N^ -R-SO3(其中R为烷氧基和芳基)结构特征的吡啶衍生物类两性表面活性剂。对合成路线和方法进行了探讨,将产物应用于酸性电镀镍溶液中表现出良好的增光效果。     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.     

Novel polyurethane coating technology through glycidyl carbamate chemistry

Glycidyl carbamate chemistry combines the excellent properties of polyurethanes with the crosslinking chemistry of epoxy resins. Glycidyl carbamate functional oligomers were synthesized by the reaction of polyfunctional isocyanate oligomers and glycidol. The oligomers were formulated into coatings with several amine functional crosslinkers at varying stoichiometric ratios and cured at different temperatures. Properties such as solvent resistance, hardness, and impact resistance were dependent on the composition and cure conditions. Most coatings had an excellent combination of properties. Studies were carried out to determine the kinetics of the curing reaction of the glycidyl carbamate functional oligomers with multifunctional and model amines. Detailed kinetic analysis of the curing reactions was also undertaken. The results indicated that the glycidyl carbamate functional group is more reactive than a glycidyl ether group. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, on October 27–29, 2004, in Chicago, IL.     

Highly moisture-proof polysilsesquioxane coating prepared via facile sol-gel process

A highly moisture-proof polysilsesquioxane coating was obtained from a new bis-silylated precursor, which was synthesized from 3-aminopropyltriethoxysilane (APTES) and m-xylylene diisocyanate (m-XDI) in tetrahydrofuran (THF) and verified by ¹H MAS NMR. For direct comparison purposes, an SiO₂ coating was also prepared by the Stöber method using tetraethoxysilane (TEOS) as the reactant. Interestingly, the coating obtained from the polysilsesquioxane sol exhibited a much higher moisture resistance capability than its counterpart, which was attributed to its more compact feature between nanoparticles as characterized by N₂ absorption experiment and transmission electron microscopy (TEM). Furthermore, its high transparency of about 92% showed potential for application in the protection of optical crystals.