Polycondensation in liquid crystalline phases of nonionic surfactants. Kinetics and morphology

Guruswamy Kumaraswamy, Mohan N. Wadekar, Vikrant V. Agrawal, Renu Pasricha

Research output: Contribution to journalArticle

Abstract

We have investigated acid-catalyzed polycondensation of alkoxysilane monomers in liquid crystalline phases of nonionic CnEm surfactants. The liquid crystalline phase is retained when the monomers polymerize. The high molecular weight molecules formed phase separate from the mesophase and are subsequently organized by it to form micron-sized particles. A variety of particle morphologies are formed by organization of the polymer particles in the mesophase. For condensation of dimethyldimethoxysilane (DMS, with trimethoxysilane, TMS as crosslinker) in hexagonal and lamellar phases, specific reaction conditions, viz. slow condensation kinetics and low crosslink density, give rod-like particles in hexagonal phases and sheet-like structures in lamellar phases. However, when higher acid concentrations are used, the reaction kinetics accelerates and irregular particles form. Irregular particles also form when the fraction of trifunctional crosslinker is increased, and finally complex flower-like structures form for condensation of trimethoxysilane in the hexagonal phase. The particle morphology formed is crucially dependent on the details of the polycondensation rate, crosslinker density and surfactant-monomer/oligomer interactions.

Original languageEnglish (US)
Pages (from-to)7961-7968
Number of pages8
JournalPolymer
Volume46
Issue number19 SPEC. ISS.
DOIs
StatePublished - Sep 8 2005

Fingerprint

Nonionic surfactants
Polycondensation
Condensation
Monomers
Crystalline materials
Kinetics
Liquids
Acids
Oligomers
Surface-Active Agents
Reaction kinetics
Polymers
Surface active agents
Molecular weight
Molecules
trimethoxysilane

Keywords

  • Nonionic
  • Surfactant
  • Templated synthesis

ASJC Scopus subject areas

  • Polymers and Plastics
  • Organic Chemistry

Cite this

Polycondensation in liquid crystalline phases of nonionic surfactants. Kinetics and morphology. / Kumaraswamy, Guruswamy; Wadekar, Mohan N.; Agrawal, Vikrant V.; Pasricha, Renu.

In: Polymer, Vol. 46, No. 19 SPEC. ISS., 08.09.2005, p. 7961-7968.

Research output: Contribution to journalArticle

Kumaraswamy, Guruswamy ; Wadekar, Mohan N. ; Agrawal, Vikrant V. ; Pasricha, Renu. / Polycondensation in liquid crystalline phases of nonionic surfactants. Kinetics and morphology. In: Polymer. 2005 ; Vol. 46, No. 19 SPEC. ISS. pp. 7961-7968.
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