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Title: Chemical Analysis and Aqueous Solution Properties of Charged Amphiphilic Block Copolymers PBA-b-PAA Synthesized by MADIX

Abstract

We have linked the structural and dynamic properties in aqueous solution of amphiphilic charged diblock copolymers poly(butyl acrylate)-b-poly(acrylic acid), PBA-b-PAA, synthesized by controlled radical polymerization, with the physico-chemical characteristics of the samples. Despite product imperfections, the samples self-assemble in melt and aqueous solutions as predicted by monodisperse microphase separation theory. However, the PBA core are abnormally large; the swelling of PBA cores is not due to AA (the Flory parameter ?PBA/PAA, determined at 0.25, means strong segregation), but to h-PBA homopolymers (content determined by liquid chromatography at the point of exclusion and adsorption transition, LC-PEAT). Beside the dominant population of micelles detected by scattering experiments, capillary electrophoresis CE analysis permitted detection of two other populations, one of h-PAA, and the other of free PBA-b-PAA chains, that have very short PBA blocks and never self-assemble. Despite the presence of these free unimers, the self-assembly in solution was found out of equilibrium: the aggregation state is history dependant and no unimer exchange between micelles occurs over months (time-evolution SANS). The high PBA/water interfacial tension, measured at 20 mN/m, prohibits unimer exchange between micelles. PBA-b-PAA solution systems are neither at thermal equilibrium nor completely frozen systems: internal fractionation of individual aggregates can occur.

Authors:
; ; ; ; ; ;
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL) National Synchrotron Light Source
Sponsoring Org.:
Doe - Office Of Science
OSTI Identifier:
959680
Report Number(s):
BNL-82666-2009-JA
Journal ID: ISSN 0021-9797; JCISA5; TRN: US201016%%824
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Colloid and Interface Science; Journal Volume: 316; Journal Issue: 2
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ADSORPTION; AQUEOUS SOLUTIONS; CHAINS; CHEMICAL ANALYSIS; CHROMATOGRAPHY; COPOLYMERS; DEFECTS; DETECTION; ELECTROPHORESIS; FRACTIONATION; POLYMERIZATION; RADICALS; SCATTERING; SEGREGATION; SWELLING; THERMAL EQUILIBRIUM; national synchrotron light source

Citation Formats

Jacquin,M., Muller, P., Talingting-Pabalan, R., Cottet, H., Berret, J., Futterer, T., and Theodoly, O. Chemical Analysis and Aqueous Solution Properties of Charged Amphiphilic Block Copolymers PBA-b-PAA Synthesized by MADIX. United States: N. p., 2007. Web. doi:10.1016/j.jcis.2007.08.025.
Jacquin,M., Muller, P., Talingting-Pabalan, R., Cottet, H., Berret, J., Futterer, T., & Theodoly, O. Chemical Analysis and Aqueous Solution Properties of Charged Amphiphilic Block Copolymers PBA-b-PAA Synthesized by MADIX. United States. doi:10.1016/j.jcis.2007.08.025.
Jacquin,M., Muller, P., Talingting-Pabalan, R., Cottet, H., Berret, J., Futterer, T., and Theodoly, O. Mon . "Chemical Analysis and Aqueous Solution Properties of Charged Amphiphilic Block Copolymers PBA-b-PAA Synthesized by MADIX". United States. doi:10.1016/j.jcis.2007.08.025.
@article{osti_959680,
title = {Chemical Analysis and Aqueous Solution Properties of Charged Amphiphilic Block Copolymers PBA-b-PAA Synthesized by MADIX},
author = {Jacquin,M. and Muller, P. and Talingting-Pabalan, R. and Cottet, H. and Berret, J. and Futterer, T. and Theodoly, O.},
abstractNote = {We have linked the structural and dynamic properties in aqueous solution of amphiphilic charged diblock copolymers poly(butyl acrylate)-b-poly(acrylic acid), PBA-b-PAA, synthesized by controlled radical polymerization, with the physico-chemical characteristics of the samples. Despite product imperfections, the samples self-assemble in melt and aqueous solutions as predicted by monodisperse microphase separation theory. However, the PBA core are abnormally large; the swelling of PBA cores is not due to AA (the Flory parameter ?PBA/PAA, determined at 0.25, means strong segregation), but to h-PBA homopolymers (content determined by liquid chromatography at the point of exclusion and adsorption transition, LC-PEAT). Beside the dominant population of micelles detected by scattering experiments, capillary electrophoresis CE analysis permitted detection of two other populations, one of h-PAA, and the other of free PBA-b-PAA chains, that have very short PBA blocks and never self-assemble. Despite the presence of these free unimers, the self-assembly in solution was found out of equilibrium: the aggregation state is history dependant and no unimer exchange between micelles occurs over months (time-evolution SANS). The high PBA/water interfacial tension, measured at 20 mN/m, prohibits unimer exchange between micelles. PBA-b-PAA solution systems are neither at thermal equilibrium nor completely frozen systems: internal fractionation of individual aggregates can occur.},
doi = {10.1016/j.jcis.2007.08.025},
journal = {Journal of Colloid and Interface Science},
number = 2,
volume = 316,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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