Swelling and Mechanical Properties of Crosslinked Hydrogels Containing N-Vinylpyrrolidone
β Scribed by Perera, Don I.; Shanks, Robert A.
- Publisher
- John Wiley and Sons
- Year
- 1996
- Tongue
- English
- Weight
- 491 KB
- Volume
- 39
- Category
- Article
- ISSN
- 0959-8103
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β¦ Synopsis
Copolymers of 2-hydroxyethyl methacrylate/N-vinyl-2-pyrrolidone (HEMA/NVP) and methyl methacrylate (MMA)/NVP were prepared in the presence of varying amounts of ethylene glycol dimethacrylate (EGDMA) and methylene diacrylamide (MDA) as crosslinkers by photopolymerisation. The resultant solid polymers were swollen to equilibrium in water at 293K to produce hydrogels. These hydrogels were characterised by soluble fraction and equilibrium water content. The gels were also characterised by compressionstrain measurements, which enabled the calculation of Young's modulus and effective crosslink density. The differences in these properties of HEMA/NVP and MMA/NVP polymer series and the effects of MDA versus EGDMA as a crosslinker were explained in terms of compositional drift of polymerisation, heterogeneous crosslinking and hydrophilicity/hydrophobicity of the components involved. In comparison with EGDMA, MDA was found to be more effective in reducing the soluble fraction of the polymers studied and to produce less rigid networks when swollen. K e y words; 2-hydroxyethyl methacrylate, methyl methacrylate, N-vinylpyrrolidone,
π SIMILAR VOLUMES
N-Vinylpyrrolidone (NVP) and methacrylates are frequently copolymerized to give hydrogels useful as contact lenses. However, the nature of their copolymerization was not well understood. In this study, the effect of a crosslinker on the photocopolymerization of NVP and 2-hydroxyethyl methacrylate (H
## Abstract Poly (acrylamideβ__co__βmethyl methacrylate) hydrogels of different ratios were prepared by using chemical and physical crosslinks to study the effect of nature of crosslinks on swelling behavior of hydrogels. The chemically crosslinked gels were prepared by using __NN__β²βmethylene bis