物理化学学报
物理化學學報
물이화학학보
ACTA PHYSICO-CHIMICA SINICA
2001年
4期
338-342
,共5页
聚氧乙烯(PEO)%十二烷基硫酸钠(SDS)%相互作用%顺磁共振
聚氧乙烯(PEO)%十二烷基硫痠鈉(SDS)%相互作用%順磁共振
취양을희(PEO)%십이완기류산납(SDS)%상호작용%순자공진
合成更疏水的自旋探针4-羰基2,2,6,6四甲基哌啶氮氧自由基2,4-二硝基苯腙.用顺磁共振(ESR)和紫外光谱法研究了十二烷基硫酸钠(SDS)0.5%(w,质量分数)聚氧乙烯(PEO)体系的分子间相互作用.ESR结果表明,此水溶液体系的微极性随SDS浓度增大而减小,并且SDS与PEO聚集体具有更加紧密的堆积结构使其结合处具有较大的微粘性,SDS与PEO间的相互作用导致PEO分子链伸展.UV表明自旋探针分子可能靠近胶束的表面存在,2,4-二硝基苯肼基团可能位于靠近SDS的硫酸根基团,定向于SDS胶束的表面,氮氧自由基基团短距离渗透到SDS胶束的碳氢核.
閤成更疏水的自鏇探針4-羰基2,2,6,6四甲基哌啶氮氧自由基2,4-二硝基苯腙.用順磁共振(ESR)和紫外光譜法研究瞭十二烷基硫痠鈉(SDS)0.5%(w,質量分數)聚氧乙烯(PEO)體繫的分子間相互作用.ESR結果錶明,此水溶液體繫的微極性隨SDS濃度增大而減小,併且SDS與PEO聚集體具有更加緊密的堆積結構使其結閤處具有較大的微粘性,SDS與PEO間的相互作用導緻PEO分子鏈伸展.UV錶明自鏇探針分子可能靠近膠束的錶麵存在,2,4-二硝基苯肼基糰可能位于靠近SDS的硫痠根基糰,定嚮于SDS膠束的錶麵,氮氧自由基基糰短距離滲透到SDS膠束的碳氫覈.
합성경소수적자선탐침4-탄기2,2,6,6사갑기고정담양자유기2,4-이초기분종.용순자공진(ESR)화자외광보법연구료십이완기류산납(SDS)0.5%(w,질량분수)취양을희(PEO)체계적분자간상호작용.ESR결과표명,차수용액체계적미겁성수SDS농도증대이감소,병차SDS여PEO취집체구유경가긴밀적퇴적결구사기결합처구유교대적미점성,SDS여PEO간적상호작용도치PEO분자련신전.UV표명자선탐침분자가능고근효속적표면존재,2,4-이초기분정기단가능위우고근SDS적류산근기단,정향우SDS효속적표면,담양자유기기단단거리삼투도SDS효속적탄경핵.
ESR and UV spectrum of the aqueous solution of sodium dodecyl sulfate(SDS)/poly(ethylene oxide)(PEO) were measured at room temperature respectively, the concentration of PEO was 0.5% (mass fraction), and the concentration of SDS (mSDS) was up to 50 mmol· kg- 1. 2,4-dinitrophylhydrazone of 2,2,6,6-tetramethyl-4-piperidine-1-oxyl (Tempone-DNPH) was synthesized and used as ESR probe. The binding site of SDS-PEO interaction, the micropolarity and microviscosity information of the microenvironments have been determined by ESR. UV spectrum gives information on the environment of 2,4-dinitrophylhydrazone group. The hyperfine coupling constant and the rotational correlation time of the spin probe reflect the microenvironment of the polymer-micelle aggregates. The micropolarity of the solutions decreases with increasing SDS concentration, the polymer-micelle aggregate forms a more compact structure at the binding site and the binding site between PEO and SDS micelles yields a strong increase of the microviscosity at the micelle-polymer interface. Spin probe is located near the surface of the micelle. 2,4-dinitrophylhydrazone group may be adjacent to the sulphate groups, and the nitroxide group penetrates a small distance into the hydrocarbon core of the micelle. The critical aggregation concentration (CAC)and polymer saturation point (PSP) of SDS-0.5 % PEO at room temperature are approximately 4 and 28 mmol· kg- 1, respectively.