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Controlling Structure and Water Miscibility of Polyion - Surfactant Ion Complex Salts

Norrman, Jens LU (2007)
Abstract (Swedish)
Popular Abstract in Swedish

Interaktionen mellan laddade polyjoner och motsatt laddade tensid joner har undersökts. Detta har gjorts genom att syntetisera det komplexa saltet (polyjon-tensid jon) och använda detta som utgångspunkt. Olika parametrar för det komplexa saltet har varierats systematiskt och effekten på struktur och vattenupptag har undersökts. Komplexa salt (CxTAPAy) bestående av alkyl trimethylammonium tensider (CxTA+, där x är längden på alkylkedjan) och poly(akrylat) (PAy, där y är polymerisationsgraden) har använts. Tensider med oligokarboxylaterna cxalat, succinate, citrat och butyl tetrakarboxylate som motjoner har även använts.



Genom att variera längden på alkylkedjan i tensiden mellan... (More)
Popular Abstract in Swedish

Interaktionen mellan laddade polyjoner och motsatt laddade tensid joner har undersökts. Detta har gjorts genom att syntetisera det komplexa saltet (polyjon-tensid jon) och använda detta som utgångspunkt. Olika parametrar för det komplexa saltet har varierats systematiskt och effekten på struktur och vattenupptag har undersökts. Komplexa salt (CxTAPAy) bestående av alkyl trimethylammonium tensider (CxTA+, där x är längden på alkylkedjan) och poly(akrylat) (PAy, där y är polymerisationsgraden) har använts. Tensider med oligokarboxylaterna cxalat, succinate, citrat och butyl tetrakarboxylate som motjoner har även använts.



Genom att variera längden på alkylkedjan i tensiden mellan 6 och 16 kunde storleken på de stavlika tensidaggregaten som formades med polymeriska motjoner vid låg vattenhalt kontrolleras. Också storleken på dde kubiska aggregaten kunde kontrolleras genom att ändra tensidens kedjelängd. Komplexa salt med C16TAPAy var i princip olösliga i vatten, med tog upp 40-50 wt% vatten i jämvikt med rent vatten. När man gick från en kort till en lång polyjon i överskott av vatten ändrades fasen i jämvikt med vatten från en kubisk till en hexagonal fas. Lösligheten för komplexa salt med lång polyjon var också högre än för komplexa salt med kort polyjon.



Genom att sänka polyjonens laddningstäthet kunde storleken på tensidaggregaten kontrolleras och kurvaturen på aggregaten ökade. Vid låga laddningstätheter försvann den långväga ordningen i systemet. Tillsatts av decanol till vattenlösningar av komplext salt minskade tensidaggregatens kurvatur och dessa blev då lamellära. Tillsats av p-xylene eller cyklohexane fick istället de stavlika aggregaten i den hexagonala fasen att svälla.



Tensider med dimeriska motjoner hade ingen blandningslucka vid högt vatteninnehåll, men tensider med tri och tetrameriska motjoner gav uphov till en fasseperation med sfäriska aggregat. Jämfört med de komplexa salten var det väldigt liten skillnade mellan tensider med tetrameriska motjoner och med korta polymeriska motjoner. Svällningen för den lamellära fasen med di-, tri-, och tetrameriska motjoner var väldigt lika. (Less)
Abstract
The interaction between poylions and oppositely charged surfactant ions has been investigated. This has been done by using the pure complex salt (polyion + surfactant ion) as a point of departure. Different parameters of the complex salt have been varied in a systematic way and the effect on structure and water miscibility has been investigated. Complex salts (CxTAPAy) consisting of alkyl trimethyl ammonium surfactants (CxTA+, with x being the alkyl chain length) and poly(acrylate) (PAy, with y being the degree of polymerization) have been used. Surfactants with the oligocarboxylate counterions oxalate, succinate, citrate, and butyl tetra-carboxylate (BTA) have also been used.



By changing the surfactant alkyl tail length... (More)
The interaction between poylions and oppositely charged surfactant ions has been investigated. This has been done by using the pure complex salt (polyion + surfactant ion) as a point of departure. Different parameters of the complex salt have been varied in a systematic way and the effect on structure and water miscibility has been investigated. Complex salts (CxTAPAy) consisting of alkyl trimethyl ammonium surfactants (CxTA+, with x being the alkyl chain length) and poly(acrylate) (PAy, with y being the degree of polymerization) have been used. Surfactants with the oligocarboxylate counterions oxalate, succinate, citrate, and butyl tetra-carboxylate (BTA) have also been used.



By changing the surfactant alkyl tail length from 6 to 16 the size of the rodlike surfactant aggregates formed with a polymeric counterion at low water content could be controlled. Also the size of the surfactant aggregates in the cubic phase found varied with surfactant tail length. The C16TAPAy systems were virtually insoluble in water, but took up 40 - 50 wt% of water in equilibrium with excess water. When changing from shorter to longer polyions, the concentrated phase in equlilibrium with excess water switched from a cubic phase to a hexagonal phase. It was also shown that the solubility of the complex salts was higher with a shorter alkyl chain length and a longer polyion.



By lowering the charge density of the polyion, the size of the surfactant aggregates decreased and the curvature of the aggregates increased. At very low charge densities, the systems lost long-range order. Additions of decanol to aqueous solutions of the complex salts decreased the curvature of the surfactant aggregates, causing a switch to a lamellar phase. By adding small oils (p-xylene, cyklohexane), the diameter of the surfactant rods in the hexagonal phase could be increased.



Surfactants with dimeric counterions did not phase separate at high water content, but tri- and tetrameric counterions caused phase separation for spherical surfactant aggregates. Compared to the complex salts, there was very little difference between the surfactant with a tetrameric counterion and the complex salt with a short polyion, indicating a fast convergence of the effect of connecting the surfactant counterions. There was very little difference in the swelling of lamellar aggregates for di-, tri-, and tetrameric counterions. (Less)
Please use this url to cite or link to this publication:
author
supervisor
opponent
  • Professor Khokhlov, Alexei, Physics Department, Moscow State University
organization
publishing date
type
Thesis
publication status
published
subject
keywords
Physical chemistry, Fysikalisk kemi, phase diagram, cubic Pm3n, hexagonal, lamellar, self diffusion, PFG NMR, SAXS, liquid crystals, polymer, counterion, complex, polyelectrolyte, surfactant
pages
134 pages
publisher
Physical Chemistry 1, Lund University
defense location
Kemicentrum Hörsal A
defense date
2007-06-08 13:15
ISBN
978-91-7422-164-0
language
English
LU publication?
yes
id
d8fa2d6d-c77d-4b33-94b4-013ef47a4f90 (old id 548757)
date added to LUP
2007-10-09 12:54:15
date last changed
2016-09-19 08:45:05
@phdthesis{d8fa2d6d-c77d-4b33-94b4-013ef47a4f90,
  abstract     = {The interaction between poylions and oppositely charged surfactant ions has been investigated. This has been done by using the pure complex salt (polyion + surfactant ion) as a point of departure. Different parameters of the complex salt have been varied in a systematic way and the effect on structure and water miscibility has been investigated. Complex salts (CxTAPAy) consisting of alkyl trimethyl ammonium surfactants (CxTA+, with x being the alkyl chain length) and poly(acrylate) (PAy, with y being the degree of polymerization) have been used. Surfactants with the oligocarboxylate counterions oxalate, succinate, citrate, and butyl tetra-carboxylate (BTA) have also been used.<br/><br>
<br/><br>
By changing the surfactant alkyl tail length from 6 to 16 the size of the rodlike surfactant aggregates formed with a polymeric counterion at low water content could be controlled. Also the size of the surfactant aggregates in the cubic phase found varied with surfactant tail length. The C16TAPAy systems were virtually insoluble in water, but took up 40 - 50 wt% of water in equilibrium with excess water. When changing from shorter to longer polyions, the concentrated phase in equlilibrium with excess water switched from a cubic phase to a hexagonal phase. It was also shown that the solubility of the complex salts was higher with a shorter alkyl chain length and a longer polyion.<br/><br>
<br/><br>
By lowering the charge density of the polyion, the size of the surfactant aggregates decreased and the curvature of the aggregates increased. At very low charge densities, the systems lost long-range order. Additions of decanol to aqueous solutions of the complex salts decreased the curvature of the surfactant aggregates, causing a switch to a lamellar phase. By adding small oils (p-xylene, cyklohexane), the diameter of the surfactant rods in the hexagonal phase could be increased.<br/><br>
<br/><br>
Surfactants with dimeric counterions did not phase separate at high water content, but tri- and tetrameric counterions caused phase separation for spherical surfactant aggregates. Compared to the complex salts, there was very little difference between the surfactant with a tetrameric counterion and the complex salt with a short polyion, indicating a fast convergence of the effect of connecting the surfactant counterions. There was very little difference in the swelling of lamellar aggregates for di-, tri-, and tetrameric counterions.},
  author       = {Norrman, Jens},
  isbn         = {978-91-7422-164-0},
  keyword      = {Physical chemistry,Fysikalisk kemi,phase diagram,cubic Pm3n,hexagonal,lamellar,self diffusion,PFG NMR,SAXS,liquid crystals,polymer,counterion,complex,polyelectrolyte,surfactant},
  language     = {eng},
  pages        = {134},
  publisher    = {Physical Chemistry 1, Lund University},
  school       = {Lund University},
  title        = {Controlling Structure and Water Miscibility of Polyion - Surfactant Ion Complex Salts},
  year         = {2007},
}