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Amphiphilic Graft Copolymer (amphiphilic + graft_copolymer)

Distribution by Scientific Domains

Polymers and Materials Science	100%

Selected Abstracts

Size Fractionation of Metal Nanoparticles by Membrane Filtration,

ADVANCED MATERIALS, Issue 5 2005
A. Akthakul
A novel thin film composite nanofiltration (NF) membrane is fabricated by coating a conventional ultrafiltration membrane with a self-assembling amphiphilic graft copolymer. The NF membranes are used in the fractionation of gold nanoparticles to achieve a well-defined particle cutoff diameter and reduced size dispersity (see Figure). [source]

A starlike amphiphilic graft copolymer with hydrophilic poly(acrylic acid) backbones and hydrophobic polystyrene side chains

JOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 16 2007
Dan Peng
Abstract A well-defined starlike amphiphilic graft copolymer bearing hydrophilic poly(acrylic acid) backbones and hydrophobic polystyrene side chains was synthesized by successive atom transfer radical polymerization followed by the hydrolysis of poly-(methoxymethyl acrylate) backbone. A grafting-from strategy was employed for the synthesis of a graft copolymer with narrow molecular weight distribution. Hydrophobic polystyrene side chains were connected to the backbones through stable CC bonds. The poly(methoxymethyl acrylate) backbones can be easily hydrolyzed with HCl without affecting the hydrophobic polystyrene side chains. This kind of amphiphilic graft copolymer can form stable sphere micelles in water. The sizes of the micelles were dependent on the ionic strength and pH value. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3687,3697, 2007 [source]

Macromonomer Purification Strategy for Well-Defined Polymer Amphiphiles Incorporating Poly(ethylene glycol) Monomethacrylate,

MACROMOLECULAR RAPID COMMUNICATIONS, Issue 8 2006
Ikuo Taniguchi
Abstract Summary: Commercial hydroxy-terminated poly(ethylene glycol) monomethacrylates (PEG-MAs) contain poly(ethylene glycol) dimethacrylate, which leads to unfavorable gel formation on polymerization. Here, hydroxy-terminated PEG-MA is readily isolated using a dimethylsilyl resin chlorinated with 1,3-dichloro-5,5-dimethylhydantoin. Solution polymerization of the isolated PEG-MA by free radical routes gives a high-molecular-weight amphiphilic graft copolymer without cross-linking. The resulting polymer is stable for long periods in ambient conditions with preservation of the hydroxy end groups of PEG. Commercial hydroxy-terminated PEG-MA can be separated readily and completely from PEG dimethacrylate contaminant with chlorinated dimethylsilyl resin. [source]

Well-defined amphiphilic graft copolymer consisting of hydrophilic poly(acrylic acid) backbone and hydrophobic poly(vinyl acetate) side chains

JOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 22 2009
Yaogong Li
Abstract A series of well-defined amphiphilic graft copolymers containing hydrophilic poly(acrylic acid) (PAA) backbone and hydrophobic poly(vinyl acetate) (PVAc) side chains were synthesized via sequential reversible addition-fragmentation chain transfer (RAFT) polymerization followed by selective hydrolysis of poly(tert -butyl acrylate) backbone. A new Br-containing acrylate monomer, tert -butyl 2-((2-bromopropanoyloxy)methyl) acrylate, was first prepared, which can be polymerized via RAFT in a controlled way to obtain a well-defined homopolymer with narrow molecular weight distribution (Mw/Mn = 1.08). This homopolymer was transformed into xanthate-functionalized macromolecular chain transfer agent by reacting with o -ethyl xanthic acid potassium salt. Grafting-from strategy was employed to synthesize PtBA- g -PVAc well-defined graft copolymers with narrow molecular weight distributions (Mw/Mn < 1.40) via RAFT of vinyl acetate using macromolecular chain transfer agent. The final PAA- g -PVAc amphiphilic graft copolymers were obtained by selective acidic hydrolysis of PtBA backbone in acidic environment without affecting the side chains. The critical micelle concentrations in aqueous media were determined by fluorescence probe technique. The micelle morphologies were found to be spheres. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6032,6043, 2009 [source]

Novel Amphiphilic Degradable Poly(, -caprolactone)- graft -poly(4-vinyl pyridine), Poly(, -caprolactone)- graft -poly(dimethylaminoethyl methacrylate) and Water-Soluble Derivatives

MACROMOLECULAR RAPID COMMUNICATIONS, Issue 9 2008
Benjamin Nottelet
Abstract New amphiphilic graft copolymers that have a poly(, -caprolactone) (PCL) biodegradable hydrophobic backbone and poly(4-vinylpyridine) (P4VP) or poly(2-(N,N- dimethylamino)ethyl methacrylate) (PDMAEMA) hydrophilic side chains have been prepared by anionic polymerization of the corresponding 4VP and DMAEMA monomers using a PCL-based macropolycarbanion as initiator. The water solubility of these amphiphilic copolymers is improved by quaternization, which leads to fully water-soluble cationic copolymers that give micellar aggregates in deionized water with diameters ranging from 65 to 125 nm. In addition, to improve the hydrophilicity of PCL- g -P4VP, grafting of poly(ethylene glycol) (PEG) segments has been carried out to give a water-soluble double grafted PCL- g -(P4VP;PEG) terpolymer. [source]