Synthesis and characterization of well-defined hydrophilic block copolymer brushes by aqueous ATRP

Kizhakkedathu, Jayachandran N.; Kumar, K. Rajesh; Goodman, Diane; Brooks, Donald E.

doi:10.1016/j.polymer.2004.08.049

Cited by 57 publications

(52 citation statements)

References 71 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[5][6][7][8][9][10][11][12] Though most of the reported studies focus on flat surfaces, spherical substrates have also been studied recently to some extent. [5,[13][14][15][16][17] In particular, it is believed that PNIPAAM modified latex particles and macroporous monoliths hold a tremendous potential of separation processes solely controlled by temperature due to their very large specific surface area and, thus, their use in commercial separation processes.…”

Section: Introductionmentioning

confidence: 99%

Swelling Deswelling Behavior of PS‐PNIPAAM Copolymer Particles and PNIPAAM Brushes Grafted from Polystyrene Particles & Monoliths

Mittal

Matsko

Butté

et al. 2008

Macro Materials & Eng

View full text Add to dashboard Cite

Two sets of emulsion particles have been synthesized. In the first set, surfactant free emulsion was used to directly synthesize PS‐PNIPAAM copolymer particles. In the second set, polystyrene particles with an ATRP initiator shell were first synthesized and subsequently grafted with PNIPAAM brushes. Swelling/deswelling behavior of both sets of particles was studied with respect to temperature and time. Monoliths with two different porosities were also formed by grafting and crosslinking of PNIPAAM chains on the aggregated particles and characterized. In all cases, swelling kinetics is sufficiently fast to use these supports for separation driven by temperature changes only. However, hindrance and cross‐linking is sensibly reducing the material performance.magnified image

show abstract

Section: Introductionmentioning

confidence: 99%

Swelling Deswelling Behavior of PS‐PNIPAAM Copolymer Particles and PNIPAAM Brushes Grafted from Polystyrene Particles & Monoliths

Mittal

Matsko

Butté

et al. 2008

Macro Materials & Eng

View full text Add to dashboard Cite

show abstract

“…Another advantage of this method is that the end of the polymer chain is capped with an active halide atom that can be reinitiated to form block copolymer brushes with addition of fresh catalyst and monomers. Hence, a variety of micro-structured brushes can in principle be constructed (Kizhakkedathu et al, 2004;Matyjaszewski and Xia, 2001;Zhao and Brittain, 2000). ATRP has therefore been used to produce several novel stationary phases for capillary electrophoresis (CE) (Huang et al, 1998;Miller et al, 2004) and for capillary zone electrophoresis (Leinweber et al, 2001).…”

mentioning

confidence: 99%

The influence of grafted polymer architecture and fluid hydrodynamics on protein separation by entropic interaction chromatography

Coad

Steels

Kizhakkedathu

et al. 2006

Biotech & Bioengineering

Self Cite

View full text Add to dashboard Cite

Entropic interaction chromatography (EIC) provides efficient size-based separation of protein mixtures through the entropy change associated with solute partitioning into a layer of hydrophilic homopolymer that has been end-grafted within the pores of a macroporous chromatography support. In this work, surface-initiated atom-transfer radical polymerization (ATRP) is used to prepare a library of EIC stationary phases covering a wide range of grafted-chain densities and molecular weights. Exhaustive chain cleavage and analysis by saponification and GPC-MALLS, respectively, show that the new ATRP synthesis procedure allows for excellent control over graft molecular weight and polydispersity. The method is used to prepare high-density grafts (up to 0.164 +/- 0.005 chains/nm(2)) that extend the range of EIC applications to include efficient buffer-exchange and desalting of protein preparations. Reducing the graft density allows for greater partitioning of high molecular weight solutes, extending the linear range of the selectivity curve. Increasing graft molecular weight also alters selectivity, but more directly affects column capacity by increasing the volume of the grafted layer. Protein partitioning in high-density EIC columns is found to decrease with mobile-phase velocity (u). Although solute mass transfer resistances leading to an increase in plate height can explain this effect, pressure drop data across the column are indicative of weak convective flow through at least a fraction of the grafted architecture. Modeling of the grafted brush properties in the presence of solvent flow by subjecting a self-consistent-field theory representation of the brush to a viscous shear force predicts that the grafted chains will tilt and elongate in the direction of flow. The shear force may therefore act to reduce the number of conformations available to chains, increasing their rigidity without significantly altering the thickness of the grafted layer. A reduction in protein partitioning is then predicted when the dependence on u of the solute entropy loss is stronger than that of the grafted polymer, a condition met at high graft densities.

show abstract

“…Several experimental studies on homopolymerization of acrylamide-based monomers by ATRP have been so far made. 21,22 On the other hand, except for a study of block copolymerization of DMAA on the surface of latexes, 23 the structural control of acrylamide-based amphiphilic block copolymer by ATRP was difficult for three main reasons according to the reports; 21 (1) catalyst inactivation by complexation with the polymers, (2) too strong bond between bromine and the terminal monomer unit of the polymers, and (3) nucleophilic displacement of terminal bromine by the penultimate y To whom correspondence should be addressed (E-mail: akashi@chem.eng.osaka-u.ac.jp, mqchen@sytu.edu.cn).…”

mentioning

confidence: 99%

Successful ATRP Syntheses of Amphiphilic Block Copolymers Poly(styrene-block-N,N-dimethylacrylamide) and Their Self-assembly

Hua

Kaneko

Liu

et al. 2005

Polym J

View full text Add to dashboard Cite

ABSTRACT:Amphiphilic AB-type block copolymers of poly(styrene-block-N,N-dimethylacrylamide) (PSt-b-PDMAA) were successfully synthesized by atom transfer radical polymerization (ATRP) of DMAA initiated by bromide end-capped PSt (polydispersity = 1.08), PSt-Br, under an appropriate catalyst/ligand system of CuCl/ N,N,N 0 ,N 0 ,N 00 -pentamethyldiethylenetriamine, where PSt-Br was pre-synthesized by ATRP of St using ethyl--bromopropionate as an initiator under CuCl/2,2-bipyridine. We investigated the self-assembly behavior of PSt-b-PDMAA with different polymerization degree (DP) of hydrophilic PDMAA block and a constant DP of PSt block in various aqueous milieus. The dynamic laser light scattering (DLLS) studies demonstrated that every PSt-b-PDMAA formed the self-assembled matters whose radii depended on both polymer and salt concentrations. Transmission electron microscope (TEM) and the chain length of PSt-b-PDMAA suggested that the present polymers formed vesicular assembly with a size-controllable hollow structure.

show abstract

Synthesis and characterization of well-defined hydrophilic block copolymer brushes by aqueous ATRP

Cited by 57 publications

References 71 publications

Swelling Deswelling Behavior of PS‐PNIPAAM Copolymer Particles and PNIPAAM Brushes Grafted from Polystyrene Particles & Monoliths

Swelling Deswelling Behavior of PS‐PNIPAAM Copolymer Particles and PNIPAAM Brushes Grafted from Polystyrene Particles & Monoliths

The influence of grafted polymer architecture and fluid hydrodynamics on protein separation by entropic interaction chromatography

Successful ATRP Syntheses of Amphiphilic Block Copolymers Poly(styrene-block-N,N-dimethylacrylamide) and Their Self-assembly

Contact Info

Product

Resources

About