Ellipsometry studies of liquid interfaces: New methodology and applications

Research output: ThesisDoctoral Thesis (compilation)

Abstract

Adsorption of several surface active agents, such as nonionics, diblock copolymers, triblock copolymers, proteins and phospholipids at the oil/water and air/water has been studied. In order to be able to do this, a new ellipsometry setup, which utilizes light guides, was developed and tested.

A new evaluation methodology was developed and tested as well. This methodology is based on performing each experiment twice, with two different substrates. The small difference in the refractive indices of these substrates will allow for resolving both the adsorbed amount and the layer thickness from deltaDelta alone, using the thin film approximation.

It was also demonstrated in which way simulated ellipsometry experiments and Brewster angle microscopy (BAM) could be utilized in interpreting ellipsometry results.

The influence of the viscosity of the oil phase on the adsorption kinetics of block coploymers at the oil/water interface has been investigated.

Measurements suggest the formation of diffuse layers at the decane/water interface during the adsorption of nonionics such as C12E5 and C18E50.

Further results show the formation of lamellar liquid crystalline phases at the oil/water interface when Phospholipids are added to the oil. These layers have been characterized using Small Angle X-ray diffraction (SAXD), ellipsometry, and BAM.

Details

Authors
  • Jan-Willem Benjamins
Organisations
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Physical Chemistry

Keywords

  • Surface and boundary layery chemistry, Ytkemi, gränsskikt, phospholipids, lactoglobulin, air/water, oil/water, block copolymers, nonionic surfactants, Brewster angle microscopy, Ellipsometry, adsorption
Original languageEnglish
QualificationDoctor
Awarding Institution
Supervisors/Assistant supervisor
  • [unknown], [unknown], Supervisor, External person
Award date2004 May 7
Publisher
  • Physical Chemistry 1, Lund University
Print ISBNs91-7422-051-9
Publication statusPublished - 2004
Publication categoryResearch

Bibliographic note

Defence details Date: 2004-05-07 Time: 10:15 Place: Lecture Hall B, Centre for Chemistry and Chemical Engineering, Lund External reviewer(s) Name: Miller, Reinhard Title: Dr.Habil Affiliation: Max Planck Institut für Kolloid- und Grenzflächenforschung, Am Mühlenberg 2, D-14476 Golm/Potsdam, Germany --- Article: New Experimental Setup To Use Ellipsometry To Study Liquid-Liquid and Liquid-Solid Interfaces,Jan-Willem Benjamins, Bengt Jönsson, Krister Thuresson and Tommy Nylander, Langmuir, 18, 6437 (2002) Article: Ellipsometric Studies of Nonionic Block Copolymers Adsorbed at the Solid/Water and Oil/Water Interfaces, Abha Kapilashrami, Martin Malmsten, Krister Eskilsson, Jan-Willem Benjamins and Tommy Nylander, Colloids and Surfaces A: Physicochemical and Engineering Aspects, 225, 181 (2003) Article: Ellipsometric Characterization of Ethylene Oxide-Butylene Oxide Diblock Copolymer Adsorption at the Air-Water Interface, Britta Rippner Blomqvist, Jan-Willem Benjamins, Tommy Nylander and Thomas Arnebrant, Manuscript Article: Ellipsometry Studies of Nonionic Surfactant Adsorption at the Oil-Water Interface, Jan-Willem Benjamins, Krister Thuresson, and Tommy Nylander, Submitted to Langmuir Article: Formation of a Liquid Crystalline Phase from Phosphatidylcholine at the Oil-Aqueous Interface,Jan-Willem Benjamins, Krister Thuresson, and Tommy Nylander, Manuscript