Acta Phys. -Chim. Sin. ›› 2001, Vol. 17 ›› Issue (04): 338-342.doi: 10.3866/PKU.WHXB20010412

• ARTICLE • Previous Articles     Next Articles

Investigation on the Interaction of Sodium Dodecyl Sulfate with Poly(Ethylene Oxide) by Electron Spin Resonance and UV Spectrum

Hai Ming-Tan;Han Bu-Xing;Yan Hai-Ke   

  1. Department of Biology and Chemical Engineering, Zibo University,Zibo 255013;Institute of Chemistry, Academia Sinica, Beijing 100080
  • Received:2000-10-10 Revised:2000-12-06 Published:2001-04-15
  • Contact: Hai Ming-Tan E-mail:mthai@263.net

Abstract: 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.

Key words: Poly(ethylene oxide), Sodium dodecyl sulfate, Interaction, ESR