Superhydrophobic and self-cleaning cellulose surfaces have been obtained via surface-confined grafting of glycidyl methacrylate using atom transfer radical polymerization combined with postmodification reactions. Both linear and branched graft-on-graft architectures were used for the postmodification reactions to obtain highly hydrophobic bio-fiber surfaces by functionalization of the grafts with either poly(dimethylsiloxane), perfluorinated chains, or alkyl chains, respectively. Postfunctionalization using alkyl chains yielded results similar to those of surfaces modified by perfluorination, in terms of superhydrophobicity, self-cleaning properties, and the stability of these properties over time.
View Article and Find Full Text PDFCCTP has been used to give alkyne-functional macromonomers which are subsequently functionalised with sugar azides and thiols, using both CuAAC and thiol-ene Michael addition reactions, to yield end-functionalised glycopolymers in a convenient manner.
View Article and Find Full Text PDFNovel thermo-responsive cellulose (filter paper) surfaces of N-isopropylacrylamide (NIPAAm) and pH-responsive cellulose surfaces of 4-vinylpyridine (4VP) have been achieved via surface-initiated ATRP. Dual-responsive (pH and temperature) cellulose surfaces were also obtained through the synthesis of block-copolymer brushes of PNIPAAm and P4VP. With changes in pH and temperature, these "intelligent" surfaces showed a reversible response to both individual triggers, as indicated by the changes in wettability from highly hydrophilic to highly hydrophobic observed by water contact angle measurements.
View Article and Find Full Text PDFDendronized polymers containing a cellulose backbone have been synthesized with the aim of producing complex molecules with versatile functionalization possibilites and high molecular weight from biobased starting materials. The dendronized polymers were built by attaching premade acetonide-protected 2,2-bis(methylol)propionic acid functional dendrons of generation one to three to a hydroxypropyl cellulose backbone. Deprotection or functionalization of the end groups of the first generation dendronized polymer to hydroxyl groups and long alkyl chains was performed, respectively.
View Article and Find Full Text PDFJ Colloid Interface Sci
January 2008
The wetting of two different model cellulose surfaces has been studied; a regenerated cellulose (RG) surface prepared by spin-coating, and a novel multilayer film of poly(ethyleneimine) and a carboxymethylated microfibrillated cellulose (MFC). The cellulose films were characterized in detail using atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). AFM indicates smooth and continuous films on a nanometer scale and the RMS roughness of the RG cellulose and MFC surfaces was determined to be 3 and 6 nm, respectively.
View Article and Find Full Text PDFChem Commun (Camb)
September 2006
Superhydrophobic bio-fibre surfaces with a micro-nano-binary surface structure have been achieved via the surface-confined grafting of glycidyl methacrylate, using a branched "graft-on-graft" architecture, followed by post-functionalisation to obtain fluorinated brushes.
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