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A rapid temperature-responsive sol-gel reversible poly(N-isopropylacrylamide)-g-methylcellulose copolymer hydrogel.

Abstract

Poly(N-isopropylacrylamide) (PNIPAAm) was grafted to methylcellulose (MC) with various feeding ratios using ammonium persulfate and N,N,N',N'-tetramethyl ethylene diamine as an initiator. FTIR results confirm the formation of PNIPAAm-g-MC copolymers. The temperature responsiveness of copolymer gels was investigated by turbidimetry, dynamic contact angle (DCA), differential scanning calorimetry and dynamic mechanical analysis (DMA). The results indicate that PNIPAAm-g-MC hydrogels are strongly temperature responsive. At lower contents of MC, the lower critical solution temperature (LCST) is decreased, whereas further increasing MC contents raises the LCSTs. It is observed that the phase transition of the hydrogels occurs reversibly within 1 min, and near body temperature, a rigid gel can be generated in a certain range of MC content. What is more, the incorporation of MC prevents the syneresis of copolymer hydrogel. DMA measurement reveals that the storage moduli (E') of the gels increase upon increasing MC contents, and moreover the values of E' go up markedly above LCST. The copolymer hydrogels hold a promise as a blood vessel barrier by tuning gelation temperature, gelation time and mechanical strength.

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  • Authors+Show Affiliations

    ,

    Research Institute of Polymeric Materials, Tianjin University, Tianjin 300072, China. wgliu@tju.edu.cn

    , , , , , , ,

    Source

    Biomaterials 25:15 2004 Jul pg 3005-12

    MeSH

    Acrylic Resins
    Biocompatible Materials
    Elasticity
    Hot Temperature
    Hydrogels
    Macromolecular Substances
    Materials Testing
    Methylcellulose
    Molecular Conformation
    Phase Transition
    Polymers
    Surface Properties
    Temperature
    Transition Temperature
    Viscosity

    Pub Type(s)

    Evaluation Studies
    Journal Article
    Research Support, Non-U.S. Gov't

    Language

    eng

    PubMed ID

    14967533

    Citation

    TY - JOUR T1 - A rapid temperature-responsive sol-gel reversible poly(N-isopropylacrylamide)-g-methylcellulose copolymer hydrogel. AU - Liu,Wenguang, AU - Zhang,Bingqi, AU - Lu,William W, AU - Li,Xiaowei, AU - Zhu,Dunwan, AU - De Yao,Kang, AU - Wang,Qin, AU - Zhao,Chengru, AU - Wang,Chuandong, PY - 2004/2/18/pubmed PY - 2004/10/9/medline PY - 2003/Jul/13/received PY - 2003/Sep/18/accepted PY - 2004/2/18/entrez SP - 3005 EP - 12 JF - Biomaterials JO - Biomaterials VL - 25 IS - 15 N2 - Poly(N-isopropylacrylamide) (PNIPAAm) was grafted to methylcellulose (MC) with various feeding ratios using ammonium persulfate and N,N,N',N'-tetramethyl ethylene diamine as an initiator. FTIR results confirm the formation of PNIPAAm-g-MC copolymers. The temperature responsiveness of copolymer gels was investigated by turbidimetry, dynamic contact angle (DCA), differential scanning calorimetry and dynamic mechanical analysis (DMA). The results indicate that PNIPAAm-g-MC hydrogels are strongly temperature responsive. At lower contents of MC, the lower critical solution temperature (LCST) is decreased, whereas further increasing MC contents raises the LCSTs. It is observed that the phase transition of the hydrogels occurs reversibly within 1 min, and near body temperature, a rigid gel can be generated in a certain range of MC content. What is more, the incorporation of MC prevents the syneresis of copolymer hydrogel. DMA measurement reveals that the storage moduli (E') of the gels increase upon increasing MC contents, and moreover the values of E' go up markedly above LCST. The copolymer hydrogels hold a promise as a blood vessel barrier by tuning gelation temperature, gelation time and mechanical strength. SN - 0142-9612 UR - https://www.unboundmedicine.com/medline/citation/14967533/A_rapid_temperature_responsive_sol_gel_reversible_poly_N_isopropylacrylamide__g_methylcellulose_copolymer_hydrogel_ L2 - http://linkinghub.elsevier.com/retrieve/pii/S0142961203008299 ER -