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1.
本文研究了通过长链烷氧甲基取代三甘醇(2)的环化反应合成一系列长链烷氧甲基-15-冠-5 (3) .在25℃, 35℃,45℃下测定了烷氧甲基冠醚化合物和(2)的表面张力,CMC及γ~C~M~C.结果显示,随着疏水链碳原子数的增加,CMC值减小,疏水链的碳原子数大于8的两亲分子在水溶液中可形成胶束.  相似文献   

2.
利用分子动力学模拟方法研究了系列离子液体型Gemini咪唑表面活性剂在水溶液中的表面活性和胶束化能力. 模拟结果表明,压力张量法得到的表面张力模拟值偏小,需乘以修正系数矫正;分子动力学模拟得到的临界胶束浓度变化规律与实验相符,可以定性比较不同结构的离子液体型Gemini咪唑分子间的胶束化能力;温度的升高会加剧分子的热运动,不利于离子液体型Gemini咪唑表面活性剂在水溶液中形成胶束;此外,研究还发现联接基不同的离子液体型Gemini咪唑表面活性剂可能遵循不同的胶束化机理.S≤6时,单个分子自组装成胶球后发生聚合形成大胶团.随着咪唑上长烷烃链碳数的增加,[Cn-4-Cnim]胶束化能力提高;而随着联接链长度增加,[C10-S-C10im]胶束化能力降低;当S >6时,分子联接基弯曲并伸入其它分子烷烃链内部以减小头基分离力,从而形成稳定的胶束或胶团.随着联接基团亚甲基数的增加,头基斥力减小,附加疏水相互作用增强,[C10-S-C10im]胶束化能力提高.  相似文献   

3.
2-丙烯酰胺基烷磺酸的溶解行为和胶体化学性质明显随烷基长短而异。由于手性碳原子的存在,与其相邻亚甲基的质子峰在~1HNMR谱上清楚地发生分裂。研究了2-丙烯酰胺基十六烷磺酸(AMC16S)在水/二氧六环混合溶剂中的聚合动力学和胶体化学性质。发现聚合速度和所得聚合物分子量均在水/二氧六环体积比为1~1/2时出现最小值,临界胶束浓度随混合溶剂中二氧六环含量的增加而增加,当水/二氧六环体积比为1/2~1/4时,观察不到胶束化现象。  相似文献   

4.
2-丙烯酰胺基烷磺酸的溶解行为和胶体化学性质明显随烷基长短而异,由于手性碳原子的存在,与其相邻亚甲基的质子峰在HNMR谱上清楚地发生分裂,研究了2-丙烯酰胺基十六烷磺酸(AMC16S)在水/二氧六环混合溶剂中的聚合动力学和胶体化化学性质,发现聚合速度和所得聚合物分子量均均在水/二氧六环体积比为1~1/2时出现最小值,临界胶束浓度随混合溶剂中二氧六环含量的增加而增加,当水/二氧六环体积比为1/2~1  相似文献   

5.
在微乳液介质中制备了系列的丙烯酰胺 (AM)与苯乙烯 (St)的双亲嵌段共聚物 (PAM b PSt) ,用紫外分光光度法测定了共聚物的组成 ,用乌氏粘度计测定了共聚物的特性粘数 [η],并用其相对表征共聚物的分子量大小 .重点研究了双亲嵌段共聚物 (PAM b PSt)疏水链段在水溶液中的缔合行为、共聚物的表面活性及其对有机物的增溶性能 ,考察了共聚物分子组成 (疏水链段含量 )与分子量对其表面活性与增溶性能的影响规律 .研究结果表明 ,由于疏水链段的憎水性 ,PAM b PSt的分子链在水溶液表面会形成表面吸附 ,从而降低水溶液的表面张力 ;而在水溶液中 ,在疏水相互作用下 ,PAM b PSt分子链中的苯乙烯疏水链段会形成分子间或分子内的胶束 ,烃类有机物可增溶其中 ;疏水链段含量越大 ,分子量越小 ,PAM b PSt的表面活性与增溶性能越强  相似文献   

6.
N—烷氧甲基取代丙烯酰胺的制备   总被引:1,自引:0,他引:1  
N—烷氧甲基取代丙烯酰胺的制备张志成,吴国忠,王胜,徐相凌(中国科学技术大学应用化学系合肥230026)关键词丙烯酰胺,阻聚剂,醚化N-烷氧甲基取代丙烯酰胺的结构通式为:CH_2=C-CONHCH_2OR_2R_1=H.CH_3;R_2=H,Me,E...  相似文献   

7.
为了研究不同疏水化修饰的聚N 异丙基丙烯酰胺(PNIPAM)高分子的水溶液性质,合成了一系列N 异丙基丙烯酰胺(NIPAM)和长链丙烯酸酯及丙烯酸胆固醇酯的共聚物.利用表面张力法证实了该类共聚物在室温下都具有良好的表面活性,在水溶液中能够形成胶束.利用荧光探针法,研究了共聚物的低温临界溶液温度(LowerCriticalSolutionTemperature,LCST),发现,随着丙烯酸酯碳链及其配比(摩尔投料比)的变化,共聚物的LCST变化不明显,但它们都比均聚的PNIPAM要低;利用荧光偏振法研究了共聚物在水溶液中的微粘度,发现其微粘度不随共聚物中丙烯酸酯链长和配比的变化而变化,说明了该类共聚物在室温下能够形成相类同的胶束内核.  相似文献   

8.
合成高分子量无规聚丙烯的研究   总被引:3,自引:0,他引:3  
用合成得到的五甲基环戊二烯基三苄氧基钛「CpTi(OBz)3」与甲基铝氧烷(MAO)组成新型催化体系进行丙烯的均聚合,研究了影响聚合活性及产物分子的各种因素,结果表明,用甲基取代钛化全物基环上的氢可使聚合产物分子是一增大一个数量级,所制得的聚丙烯为无规聚丙烯,具有高分子量。  相似文献   

9.
采用离子交换法,由氯化1-丁基-3-甲基咪唑鎓(C_4mimCl)和烷基硫酸钠合成了一系列无卤素的阴离子表面活性离子液体—烷基硫酸1-丁基-3-甲基咪唑鎓盐[C_4mim][C_nH_(2n+1)SO_4](n=8,12,16),利用表面张力仪、稳态荧光光谱等手段考察了表面活性离子液体在水溶液表面及体相中的聚集行为。结果表明,与传统无机反离子相比,有机咪唑阳离子[C_4mim]~+作为反离子的离子液体型表面活性剂具有较高的表面活性,[C_4mim]~+产生的氢键引起的抑制分子规则排列的作用小于其促进分子有序排列的疏水作用。长烷基链的阴离子是界面膜及胶束的主要组成成分,阴离子疏水烷基碳链的增长虽然可促进胶束的形成,但却在一定程度上抑制[C_4mim]~+参与界面或胶束的形成;阴离子所带烷基链越长,越不利于阳离子[C_4mim]~+参与界面膜或胶束的形成,界面膜或胶束中表面活性剂排布越松散,即界面张力越大,体系中胶束聚集数较小。  相似文献   

10.
崔慧  涂燕  尚亚卓  刘洪来 《化学通报》2017,80(7):672-678
采用离子交换法,由1-丁基-3甲基咪唑氯盐(C4mimCl)和烷基硫酸钠合成了一系列无卤素的阴离子表面活性离子液体—1-丁基-3-甲基咪唑烷基硫酸酯[C4mim][CnH2n 1SO4](n=8,12,16),利用表面张力仪、稳态荧光光谱等手段考察了表面活性离子液体在水溶液表面及体相中的聚集行为,结果表明,与传统无机反离子相比,有机咪唑阳离子[C4mim] 作为反离子的离子液体型表面活性剂具有较高的表面活性,[C4mim] 产生的氢键引起的抑制分子规则排列的作用小于其促进分子有序排列的疏水作用。长烷基链的阴离子是界面膜及胶束的主要组成成分,阴离子疏水烷基碳链的增长虽然可促进胶束的形成,但却在一定程度上抑制[C4mim] 离子参与界面或胶束的形成;阴离子所带烷基链越长,越不利于阳离子[C4mim]+参与界面膜或胶束的形成,界面膜或胶束中表面活性剂排布越松散,即界面张力越大,体系中胶束聚集数较小。  相似文献   

11.
A new series of subphthalocyanines substituted axially with an oligoethylene glycol chain [SPcB(OCH(2)CH(2))(n)OH, n = 3 (2) or 4 (3)] or a p-phenoxy oligoethylene glycol methyl ether chain [SPcBOC(6)H(4)(OCH(2)CH(2))(n)OCH(3), n = 2 (4) or 3 (5)] have been synthesised by substitution reactions of boron subphthalocyanine chloride SPcBCl (1) with the corresponding oligoethylene glycols, and characterised with various spectroscopic methods and elemental analysis. The molecular structure of one of these compounds (subphthalocyanine 4) has also been determined. As revealed by absorption spectroscopy, these compounds are essentially non-aggregated in DMF. The low aggregation tendency of these compounds results in a strong fluorescence emission and high efficiency to generate singlet oxygen. All these subphthalocyanines, being formulated with Cremophor EL, function as efficient photosensitisers and exhibit a high photocytotoxicity against HepG2 human hepatocarcinoma and HT29 human colon adenocarcinoma cells. The phenoxy analogues 4 and 5 show a relatively high photostability and are particularly potent towards these cell lines, with IC(50) values down to 0.02 microM.  相似文献   

12.
In this paper a new class of multichain non-ionic surfactants based on lysine with two octyl, decyl, dodecyl or tetradecyl chains and one polydispersed polyoxyethylene diethanolamide head group are introduced. Measurements at air/water interface and bulk solution of surface-active properties such as surface tension and critical micelle concentration were made. These compounds were obtained by condensation of the corresponding long chain Nα, N x diacyl lysine with a polydispersed oxyethylene diethanolamine which was prepared in our laboratory. A preliminary study of their water solubility properties is also described. The surface-active properties were evaluated by measuring the variation of surface tension and the formation of a presumable CMC as a function of concentration in the aqueous solution. All compounds were soluble in water up to 0.5% (w/v). They showed normal surface tension values in water solution and presented higher CMC than classical polyoxyethylene alcohols non ionic surfactants with the same number of carbon atoms in the hydrophobic moiety. In this series when each chain is increased by four methylene units, the CMC falls to about one-hundreth of its previous value.  相似文献   

13.
A series of ethoxylated sodium monooctyl sulfosuccinates [E(n)SMOSS] and ethoxylated sodium monolauryl sulfosuccinates [E(n)SMLSS] have different units of ethylene oxide (n = 9, 14, 23) were synthesized. The surface and thermodynamic properties of these surfactants have been compared with sodium dioctyl sulfosuccinate surfactant (SDOSS) as a commonly used surfactant. The surface tension measurements at 25, 35, 45, and 55°C were used to determine of the critical micelle concentration (CMC) and surface active properties of these surfactants. The effect of the ethylene oxide (EO) unit and the alkyl chain length on the surface properties for the prepared surfactants was studied. The results show that the ethoxylated sodium monoalkyl sulfosuccinates generally have lower values of CMC than that of sodium dioctyl sulfosuccinate. The values of surface active parameters indicate that the ethoxylated sodium monooctyl sulfosuccinates and ethoxylated sodium monolauryl sulfosuccinates surfactants have adsorption properties better than the sodium dioctyl sulfosuccinate surfactant as a resulted presence of ethylene oxide in molecules of the prepared surfactants. The thermodynamic parameters show that the (EO) unites in the chemical structure of ethoxylated sodium monoalkyl sulfosuccinate surfactants improve their micellization and adsorption properties.  相似文献   

14.
A series of novel macrocyclic multidentate crown compounds have been prepared from a series of dioxodioic acids. The dioxodioic acids were prepared by treating various oligoethylene glycols or amines with maleic, succinic, citraconic, and glutaric anhydrides. The crown compounds were then synthesized from the dioxodioic acid chlorides obtained from the diacids and various oligoethylene glycols or ethylene diamine. The following macrocyclic compounds have been prepared: 1,4,9,12-tetraoxacyclohexadecane-5,8,13,16-tetrone ( 1 ); 1,4,7,10,15,18-hexaoxacyclodocosane-11,14,19,22-tetrone ( 2 ); 1,4-dioxa-9,12-diazacyclohexadecane-5,8,13,16-tetrone ( 3 ); 1,4,7-trioxa-12,15-diazacyclonoadecane-8,11,16,19-tetrone ( 4 ); 1,4,7,10-tetraoxa-15,18-diazacyclodocosane-11,14,19,22-tetrone ( 5 ); 4-benzyl-1,7,12,15-tetraoxa-4-azacyclonona-decane-8,11,16,19-tetrone ( 6 ); 1,4,7,12,15,18-hexaoxacyclodocosa-9,20-diene-8,11,19,22-tetrone( 7 ); and 9,21-dimethyl-1,4,7,12,15,18-hexaoxacyclodocosa-9,20-diene-8,11,19,22-tetrone ( 8 ) (Figure 1).  相似文献   

15.
《Tetrahedron: Asymmetry》2006,17(17):2538-2547
Seven new enantiopure proton-ionizable crown ethers containing a dialkylhydrogenphosphate moiety were prepared starting from optically active dialkyl-substituted oligoethylene glycols and phosphorus oxychloride followed by mild hydrolysis of the resulting macrocyclic chlorophosphates. Pentaethylene glycols having primary hydroxyl groups gave good yields of 17-crown-6 type ethers. Pentaethylene glycols with secondary hydroxyl groups rendered about the same amount of 17-crown-6 ethers and open chain dihydrogenphosphates in low yields. Tetraethylene glycols are reluctant to undergo macrocyclization with phosphorus oxychloride, especially the ones which contain secondary hydroxyl groups.  相似文献   

16.
Self-assembled monolayers (SAMs) of bis-thioctic ester derivatives of oligoethylene glycols were prepared. When the number of (-CH2-CH2-O-)n units in these podands was either five or six, the corresponding SAMs showed ion binding properties and selectivities similar to those exhibited by 15-crown-5 or 18-crown-6 in aqueous solution, respectively. Impedance data for the SAMs as a function of metal ion concentrations were fitted by using a Langmuir isotherm to determine the association constants (Ka) with the different ions. The SAM derived from the n = 5 compound is selective for Na+ while that with n = 6 is selective for K+. Results presented here confirm the formation of ion recognition domains during self-assembly of acyclic polyethylene glycol derivatives on gold surfaces; this suggests that surface-confined pseudocrown ether structures are formed.  相似文献   

17.
Novel surfactants of perfluorinated double long-chain salts with divalent counterion of separate electric charge, 1,1-(1,omega-alkanediyl)bispyridinium diperfluorononanoate (CnBP(FC9)2, n = 2, 4, 6, 8) were newly synthesized. Their solution properties were investigated by surface tension measurement over the temperature range from 298.2 to 313.2 K, where magnesium diperfluorononanoate (Mg(FC9)2) was employed as a reference surfactant with divalent counterion of concentrated electric charge. From change of surface tension with concentration, the critical micelle concentration (CMC), surface excess (Gamma), apparent molecular surface area (A), and -log(concentration to reduce surface tension of water by 20 mN m-1) (pC20) were determined. The CMC values of CnBP(FC9)2 decreased with increasing charge separation and with increasing temperature, where the values of CnBP(FC9)2 were much smaller than those of Mg(FC9)2. In addition, the pC20 values of the former were also much larger than those of the latter. These results indicate a strong influence of the extent of charge separation or the spacer length of the counterions upon surface activity of the fluorinated surfactants. The surface excess or the corresponding apparent molecular surface area monotonously changed with the spacer length (n < or = 6), whereas the behavior for n = 8 was much different from the other CnBP(FC9)2 due to conformational change in the in-between alkanediyl chain. The entropy changes (Deltas) for the surface adsorption or condensation were found to be mostly negative for CnBP(FC9)2, where the changes approached zero with an increase in the charge separation. On the other hand, the changes for Mg(FC9)2 were positive over the whole concentration below the CMC. In addition, Brewster angle microscopy indicated no condensation of the present surfactants just at the air/solution interface.  相似文献   

18.
We report a practical and one‐pot synthesis of novel series of ω‐(oxathiolan‐2‐thione‐5‐yl)‐α‐ oxazolidin‐2‐ones ( 3a‐h ). The obtained compounds have been designed, synthesized via reaction of oligoethylene glycols diglycidyl ethers, isocyanate and carbon disulfide in the presence of catalytic amount of lithium bromide. A variety of important oxazolidinone derivatives can be obtained from simple starting materials in good yields and the biological activity of these new products will be investigated in complementary study.  相似文献   

19.
The present work describes the synthesis of some heterocyclic compounds based pyrazole, triazole, pyrimidine, and pyridine derivatives. The synthesis of these heterocycles have been carried out by the reaction of ethyl‐3‐(octadecylamino)‐3‐oxopropanoate ( 2 ) with various reagents under suitable reaction conditions. Propoxylation of these heterocycles by using a number of propylene oxide moles afforded nonionic surface active agents, incorporating long alkyl chain having suitable molecular weight to obtain amphiphilic materials with hydrophilic–lipophilic equilibrium, which enhances solubility and biodegradability, hence lowers the toxicity to human beings, and becomes environmentally friendly. A series of useful properties such as surface and interfacial tensions, cloud point, wetting time, foam height, emulsion stability, critical micelle concentration (CMC), surface tension at the CMC (γCMC), efficiency (PC20), effectiveness (πCMC), surface excess (Γmax), and surface area (Amin) have been estimated. In addition, the antimicrobial activities of these compounds were screened.  相似文献   

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