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1.
4-乙烯吡啶型聚皂与表面活性剂相互作用的研究   总被引:1,自引:0,他引:1  
1实验部分11试剂N-乙基聚4-乙烯吡啶溴化盐(QPVPE)和N-十二烷基聚4-乙烯吡啶溴化盐(QPVPD)是根据文献方法合成〔7〕,其中QPVPD-20、QPVPD-30分别表示溴十二烷与4-乙烯吡啶投料的物质的量比为20%和30%.SDS(北京化工厂,分析纯),BDDAC(北京化工厂,分析纯)使用前未做进一步提纯.12待测溶液的配制向5×10-5mol/L的表面活性剂溶液(SDS、BDDAC)中,在缓慢搅拌下加入质量浓度为25g/L的QPVPE和QPVPD溶液,最后加入蒸馏水定容.温度保持在30℃,溶液静置24h后进行测定.13实验方法相对粘度采用乌氏粘度计在(30±1)℃水浴中测定.QPVPE、QPVPD与SDS混合溶液的可见光透射率采用721分光光度计在室温下测定.以质量浓度为5g/L的聚合物溶液为参比,波长为420nm,比色皿厚度为1mm.采用DDS-12A数字式电导率仪(电极为DJS-1光亮电极).温度补偿为25℃.2结果与讨论QPVPD分子链上的长链疏水烷基在水溶液中可聚集成胶束,形成紧缩构象,这种聚集体又称为疏水微区(Hydrophobicmicrodomain).同聚电解质类似,聚皂  相似文献   

2.
在水溶液中进行了表面活性单体丙烯酰胺基十四烷基磺酸钠(NaAMC14S)与丙烯酰胺(AM)的均相共聚合, 制备了具有微嵌段结构的疏水缔合聚丙烯酰胺NaAMC14S/AM, 合成了阳离子型Gemini表面活性剂二溴化-N,N′-二(二甲基十二烷基)己二铵(C12C6C12Br2), 采用表观粘度法和荧光探针法研究了共聚物NaAMC14S/AM与Gemini表面活性剂C12C6C12Br2的相互作用. 研究结果表明, 疏水缔合聚丙烯酰胺NaAMC14S/AM与Gemini表面活性剂C12C6C12Br2之间存在着很强的相互作用, 既存在静电相互作用, 又存在强烈的疏水相互作用, 表现在以下几方面: C12C6C12Br2的加入, 使共聚物NaAMC14S/AM在浓度小于其临界缔合浓度(cac)时即发生分子间的缔合; C12C6C12Br2在低于其临界胶束浓度时, 就与共聚物NaAMC14S/AM形成混合胶束; 当共聚物的浓度为0.30%(w)时, 随着C12C6C12Br2加入量的增多, 共聚物水溶液的粘度会发生大幅度的增加, 在最大值处粘度竟提高了3个数量级. 研究还发现, 共聚物NaAMC14S/AM与C12C6C12Br2之间的相互作用还与共聚物分子链中的疏水微嵌段含量有关, 疏水微嵌段含量越多, NaAMC14S/AM与C12C6C12Br2之间的相互作用越强, 溶液粘度增加的程度越大.  相似文献   

3.
聚电解质复合物溶解性研究   总被引:2,自引:0,他引:2  
报道了聚电解质复合物的一种新的溶剂体系———离子表面活性剂剂的水溶液 ,研究了表面活性的用量及结构、温度、外加小分子电解质对复合物溶解性的影响 ,初步探讨了溶解机理 ,通过扫描电镜观察了复合物溶解后在溶液中的形态 .研究表明 ,当复合物与离子表面活性剂定量结合到一定程度时 ,就会使复合物发生溶解 .表面活性剂碳链长度的增加、温度的提高均会对复合物的溶解有不同程度的促进 .加入少量的无机电解质如氯化钠 ,会促进复合物的溶解 ,若氯化钠加入量过多 ,反而不利于复合物的溶解 .复合物的溶解机理被认为是表面活性剂的解离作用和疏水作用二者的协同 .  相似文献   

4.
合成了系列壬基酚聚氧乙烯醚二聚表面活性剂(DNP)和三聚表面活性剂(TNP), 用核磁共振、红外光谱和元素分析等手段对其结构进行了表征, 并用表面张力法和稳态荧光法对DNP和TNP的表面性能进行了研究. 结果表明, 随着氧乙烯(EO)单元数的增长, DNP和TNP的临界胶束浓度(cmc)值逐渐增大; DNP和TNP的cmc值较相应的单体壬基酚聚氧乙烯醚表面活性剂(NP)明显降低, 显示了较高的表面活性、吸附能力和润湿能力.  相似文献   

5.
疏水改性聚电解质的荧光探针光谱   总被引:7,自引:0,他引:7  
流水改性聚电解质或聚皂(PolysoaP)是在亲水性聚电解质的侧链或主链上键合少量的强流水性基团的聚合物l',']流水基团一般采用长链烷基(通常碳原子数大于刚*一、也有用硅氧烷、氟碳化合物进行疏水改性问由干这种聚合物分子链上带有两性亲媒基团,因此,又被称为高分子表面  相似文献   

6.
烷基甲基二烯丙基溴化铵共聚物是一种新型疏水改性的聚皂,应用多种核磁共振分析技术对其结构和共单体的组成进行了定量的讨论.研究结果表明,在测定化学结构和性质上比较接近的共单体组成时,核磁共振方法是一种有效的工具.  相似文献   

7.
聚电解质复合物 ( PEC)因其独特的物理化学性质而受到广泛关注 .对其研究主要集中在其结构及形成的影响因素 ,如聚电解质的分子量 [1,2 ] 、电荷密度、电荷强弱 [1,2 ] 及溶液离子强度 [3,4 ] ,而很少有关于聚电解质复合物溶解性的报道 [5,6 ] .一般认为组成 PEC的聚正离子 ( PC)和聚负离子 ( PA)之间 ,通过离子键形成网状交联结构而不溶于水及有机溶剂 .只有一种特殊的溶剂体系屏蔽溶剂可溶解此类复合物[7,8] .本文报道一类新的聚电解质复合物 :以二苯胺重氮树脂 DR为聚正离子 ,苯乙烯 -马来酸酐碱性水解物 ( PSMNa)为聚负离子的 P…  相似文献   

8.
聚(2-丙烯酰胺甲基-6-十二烷基硼酸二乙醇胺酯)(PADB)是一类两亲性聚硼酸酯.本文通过表面张力法考察了不同相对分子质量的PADB水溶液的表面活性;重点研究了PADB与十二烷基苯磺酸钠(SDBS)在0.5 mol.L-1 NaCl溶液中的相互作用,通过正规溶液理论,计算PADB/SDBS混合体系的胶束化参数,并与单体ADB/SDBS混合溶液体系进行了比较.结果表明,PADB相对分子质量可达1.5×104-3.5×104,随分子量增加,PADB水溶液中临界胶束浓度(cmc)增大,但cmc时的表面张力(γcmc)维持在31 mN.m-1左右(298 K);加入PADB后,SDBS溶液表面张力-浓度对数(γ-lgc)曲线出现两处转变点,即c1和c2点,但c1和c2皆小于纯SDBS溶液的临界胶束浓度(cmcSDBS),即c1c2cmcSDBS.PADB加入量越大,相对分子质量越低,SDBS溶液的表面活性越强.将聚硼酸酯PADB溶液视为特殊状态的单体ADB溶液,通过近似处理,计算得到PADB/SDBS混合胶束中相互作用参数βm在-2.4到-4.7之间,活度系数f1m1,表明聚硼酸酯PADB与SDBS有较强的相互作用;当混合体系中PADB的ADB结构单元摩尔分数x1为0.47时,|βm|达到最大.相比于单体ADB/SDBS混合体系,当x10.8时,PADB/SDBS混合体系|βm|值较大,相互作用更强;随x1增大,混合胶束中聚合物PADB的ADB结构单元摩尔分数x1m不断增加,但其值低于ADB/SDBS混合体系.  相似文献   

9.
疏水缔合聚丙烯酰胺与阳离子双子表面活性剂的相互作用   总被引:1,自引:0,他引:1  
通过表面张力法和电导率法分别考察了阳离子双子表面活性剂(12-2-12)与非离子疏水缔合聚丙烯酰胺(HMPAM)和普通聚丙烯酰胺(PAM),传统表面活性剂十二烷基三甲基溴化铵(DTAB)与HMPAM和PAM之间的相互作用。结果表明,12-2-12 HMPAM复合体系与12-2-12水溶液体系相比,在w(聚合物含量)CMC时,复合体系的电导率(κ)具有下降的趋势,且κ随着w的增大下降的趋势越明显,说明12-2-12与HMPAM之间存在相互作用。  相似文献   

10.
皮瑛瑛  尚亚卓  刘洪来  胡英 《化学学报》2005,63(14):1281-1287
摘要 采用荧光探针法和电导法研究了正离子偶联表面活性剂(C12H25(CH3)2N-(CH2)6-N(CH3)2C12H25•2Br) (12-6-12• 2Br)和带相反电荷聚电解质聚丙烯酸钠(NaPA)的相互作用, 结果表明: 由于静电相互作用, 12-6-12•2Br和NaPA之间可以形成类胶束或复合物. 对比十二烷基三甲基溴化铵(DTMAB)与NaPA复配体系的荧光光谱, 发现偶联表面活性剂与NaPA的相互作用强于传统表面活性剂. 此外, 还研究了盐和醇对偶联表面活性剂/聚丙烯酸钠的复配体系微极性的影响, 发现盐和醇对表面活性剂在聚电解质上形成类胶束和复合物的溶解都有一定的促进作用.  相似文献   

11.
A series of tail-type cationic surface-active monomers with the cationic charge at the -end (1; ST-Cm-AB, m=5, 7, and 9, where ST is a styrenic group, Cm the alkylene chain at the 4-position of styrene, and AB is alkyltrimethylammonium bromide) have been synthesized as a novel cationic polymerizable surfactant. Their fundamental physicochemical properties such as critical micelle concentration (cmc) and weight-average aggregation number of the micelle (Nw(agg)) have been characterized in water at 25 °C by static light-scattering measurements. The cmc values determined for the tail-type surfactant monomers are two-orders of magnitude smaller than those of the corresponding head-type cationic surfactant monomers (2; ST-C1-AC-Cm). The Nw(agg) of ST-Cm-AB is 68 for m=5, 156 for m=7, and 413 for m=9. Free-radical homopolymerization of ST-C7-AB proceeds very rapidly in water as a result of organization in the micelle to afford the corresponding amphiphilic cationic polyelectrolyte with Mw=3.63×106 and 23 nm hydrodynamic radius at 25 °C. Emulsion copolymerization of styrene with ST-Cm-AB also proceeds rapidly to afford very stable cationic polystyrene latex particles of 30–60 nm diameter. The amphiphilic cationic polyelectrolyte of poly(ST-C7-AB) is likely to assume a compact conformation with high segment density in 0.1 mol L–1 NaCl in water. Addition of hydrophobic aromatic counter-anions with an weak acid group, for example potassium hydrogen phthalate (PHK) and sodium salicylate, to a salt-free aqueous solution of poly(ST-C7-AB) induces intermolecular aggregation and increases the solution viscosity substantially, often producing gels and precipitation at high polymer concentration.  相似文献   

12.
Hydrophobically modified poly(4-vinyl pyridines) by alkyl bromides arekinds of polysoap similar to the surfactant. Properties of dilute solutions were studiedthrough the viscosity measurements in pure water and NaCl solutions. In aqueous solu-tions of polysoaps hydrophobic interaction can be attributed to aggregation of hydrophobicgroups of the polysoap main chains. The hydrophobic groups of polysoap can aggregate toform hydrophobic microdomains (micelles) in aqueous solution. This is a compact confor-mation. The formation of such microdomains is a process of dynamic equilibrium.  相似文献   

13.
This review covers the effects of hydrophobic counterions on the phase behavior of ionic surfactants and the properties of the phases. Mixing hydrophobic counterions with ionic surfactant micellar solutions may initiate the micellar growth and transform the micellar microstructure into different morphologies. This behavior may also be achieved by mixing ionic surfactants with hydrophilic counterions, although higher counterionic concentrations are then required. First, the role of hydrophilic and hydrophobic counterions in regards to micelle growth is discussed. Second, the effect of the hydrophobic counterion on the self-assembly of cationic and anionic surfactants and their viscoelastic behavior are presented. Third, the relationships between geometry, hydrophobicity and their consequences on micellar growth for different hydrophobic counterions are reviewed. Forth, the influence of hydrophobic counterion substituents (substitution pattern) on the phase behavior is discussed. Some results we previously obtained for different isomers of hydroxy naphthaoic acids and the cationic surfactant cetyltrimethylammonium hydroxide are included. With these systems the effect that the hydrophobic counterion microenvironment has on the phase behavior, rheological behavior and the micellar microstructure is discussed. The results from other research groups are also discussed.  相似文献   

14.
徐乐颜  王凝月  杨明玲  王小永 《化学通报》2019,82(12):1104-1109
本文研究了带有不同负电荷量的κ-卡拉胶和λ-卡拉胶对牛血清蛋白/卡拉胶复合物包载姜黄素的增强作用。卡拉胶通过与牛血清蛋白之间的静电吸引作用,可以生成高稳定性的牛血清蛋白/卡拉胶复合物。相比纯牛血清蛋白,牛血清蛋白/卡拉胶复合物能够显著提高姜黄素的溶解度和稳定性。姜黄素的紫外和荧光光谱表明姜黄素主要是通过疏水作用缔合于牛血清蛋白的疏水微区。卡拉胶与牛血清蛋白的静电吸引作用能够稳定牛血清蛋白的折叠结构,从而使牛血清蛋白为姜黄素提供更加疏水的缔合微环境。相比纯牛血清蛋白和牛血清蛋白/κ-卡拉胶复合物,带有更高负电荷的λ-卡拉胶与牛血清蛋白生成的牛血清蛋白/λ-卡拉胶复合物与姜黄素有更大的缔合常数和pKa1。  相似文献   

15.
两亲分子由于具有自组装性质,如表面活性剂分子自组装形成胶束,囊泡,天然的磷脂分子自组装形成脂质体,继而参于生物膜的形成,这是大家所熟悉的.高分子两亲分子尤其是两亲性两嵌段高分子具有自组装性质,并形成规整性好的聚集体[1~3].聚电介质 表面活性剂体系...  相似文献   

16.
疏水链段对两亲性三嵌段共聚物在水中聚集行为的影响   总被引:1,自引:1,他引:1  
以结构明确的两端为短的聚苯乙烯(PS)或聚甲基丙烯酸甲酯(PMMA)链段,中间为长的聚乙二醇(PEG)链段的PS-b-PEG-b-PS和PMMA-b-PEG-b-PMMA两亲性三嵌段共聚物为对象,研究了PS和PMMA链段对其在水中形成胶束和凝胶的影响.两种三嵌段共聚物在水中形成以PS或PMMA链段为核、PEG链段为壳的球形胶束,流体力学半径Rh,app为15.3~24.3 nm,并随PEG链段长度增长而增大.临界胶束浓度CMC均小于0.01 mg/mL,随着PS和PMMA链段长度的增加而减小.PS-b-PEG-b-PS浓度高于4.5 wt%可形成较强的疏水缔合的物理凝胶,平衡模量Ge可达到103Pa;PMMA-b-PEG-b-PMMA浓度高于7.5 wt%可以形成弱的凝胶,Ge<10 Pa.凝胶的储存模量G′和损耗模量G″均随着PS或PMMA链段的增长而增大.  相似文献   

17.
两亲分子由于具有自组装性质,如表面活性剂分子自组装形成胶束,囊泡,天然的磷脂分子自组装形成脂质体,继而参于生物膜的形成,这是大家所熟悉的.高分子两亲分子尤其是两亲性两嵌段高分子具有自组装性质,并形成规整性好的聚集体[1~3].聚电介质表面活性剂体系...  相似文献   

18.
Rizvi SA  Shamsi SA 《Electrophoresis》2005,26(21):4172-4186
Four alkenoxy leucine-based surfactants with C8-C11 chains containing a terminal double bond, and one C11 chain surfactant with a terminal triple bond are synthesized and characterized in monomeric and polymeric forms. These polymeric pseudophases are then utilized to study the influence of chain length and DP for the enantioseparations of seven beta-blockers in MEKC. Variations in chain length and concentration of polymeric surfactants showed significant effects on the chiral resolution (Rs) and efficiency (N). A relatively large elution range combined with the highest polarity and aggregation number (A) but the lowest retention time, partial specific volume, and optical rotation generated with C8-polymeric surfactant results in simultaneous enantioseparation of all seven beta-blockers with higher N and R(s). In particular, highly hydrophobic beta-blockers are better resolved with shorter hydrocarbon chain even at higher surfactant concentration, which is unachievable with longer chain surfactant. On the other hand, polymer derived from C11-triple bond provided smaller A value compared to C11-double bond surfactant. However, chiral Rs of hydrophobic beta-blockers are still achievable with the C11-triple bond surfactant with enhanced N and shorter analysis time. In addition, effect of polymerization concentration is evaluated by polymerizing all five surfactants at five times their respective CMCs and 100 mM equivalent monomer concentrations. Polymerization of shorter chain (C8 and C9) double-bonded surfactants at five times their respective CMCs results in higher A values with better chiral Rs and N compared to the same two surfactants polymerized at 100 mM.  相似文献   

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