Silk fibers were chemically modified by grafting with polyethylene glycol dimethacrylate(PEGDMA).The structure and thermal properties of these grafted silk fibers were investigated in relation to the graft yield by us...Silk fibers were chemically modified by grafting with polyethylene glycol dimethacrylate(PEGDMA).The structure and thermal properties of these grafted silk fibers were investigated in relation to the graft yield by using DSC,TGA and dynamic viscoelastic measurements.The DSC and TGA results showed that the decomposition peak of grafted silk fibers shifted to higher temperatures,suggesting that grafting of silk fibers with PEGDMA can improve the thermal stability.Dynamic mechanical data showed that the major loss peak became broader and its temperature shifted to lower values following the increase of the graft yield.The cross-linkage between the molecules of silk fibers and PEGDMA may limit macromolecular motion in silk fibers,so,the peak of loss modulus(E″) determined by dynamic viscoelastic measurements became lower and the initial position of this peak shifted to higher temperature,when the graft yield increased.展开更多
A new method has been established to graft vinyl monomers onto silk fabrics by ultraviolet rays without any initiator or photosensitizer, in an attempt to improve undesirable properties of the materials with increased...A new method has been established to graft vinyl monomers onto silk fabrics by ultraviolet rays without any initiator or photosensitizer, in an attempt to improve undesirable properties of the materials with increased wrinkle recovery, better dyeing ability and color-fastness, and higher resistance to photo-yellowing, etc. In this work, ef- fectiveness of different types of UV devices and experimental conditions of the photo-induced graft-copolymeri- zation were investigated to control the influential factors on the grafting yield and properties of the graft-copolymer. Surface characteristics and structure changes, thermal properties and wrinkle resistance of grafted silk fabrics were studied. The grafted silk fabrics showed improved properties in crease resistance, dyeing ability and color-fastness, and heat stability as well. In detail, graft-copolymerization of 2-(Dimethylamino)ethyl methacrylate onto silk fabrics can make silk fabrics undergo from slight to drastic changes in their dyeing behavior, i.e., rate of dyeing and uptake of acid dyes. Different reaction systems of the same monomer can lead to reverse dyeing properties, indicating not only the function but also the structure affects the properties of grafted silk fab- rics, especially the color-fastness. The UV light graft copolymerization method is of significance in silk industrial applications in terms of the facility cost, operation convenience and grafting efficiency, in comparison to Co 60 γ-ray and electron beam irradiation facilities.展开更多
文摘Silk fibers were chemically modified by grafting with polyethylene glycol dimethacrylate(PEGDMA).The structure and thermal properties of these grafted silk fibers were investigated in relation to the graft yield by using DSC,TGA and dynamic viscoelastic measurements.The DSC and TGA results showed that the decomposition peak of grafted silk fibers shifted to higher temperatures,suggesting that grafting of silk fibers with PEGDMA can improve the thermal stability.Dynamic mechanical data showed that the major loss peak became broader and its temperature shifted to lower values following the increase of the graft yield.The cross-linkage between the molecules of silk fibers and PEGDMA may limit macromolecular motion in silk fibers,so,the peak of loss modulus(E″) determined by dynamic viscoelastic measurements became lower and the initial position of this peak shifted to higher temperature,when the graft yield increased.
文摘A new method has been established to graft vinyl monomers onto silk fabrics by ultraviolet rays without any initiator or photosensitizer, in an attempt to improve undesirable properties of the materials with increased wrinkle recovery, better dyeing ability and color-fastness, and higher resistance to photo-yellowing, etc. In this work, ef- fectiveness of different types of UV devices and experimental conditions of the photo-induced graft-copolymeri- zation were investigated to control the influential factors on the grafting yield and properties of the graft-copolymer. Surface characteristics and structure changes, thermal properties and wrinkle resistance of grafted silk fabrics were studied. The grafted silk fabrics showed improved properties in crease resistance, dyeing ability and color-fastness, and heat stability as well. In detail, graft-copolymerization of 2-(Dimethylamino)ethyl methacrylate onto silk fabrics can make silk fabrics undergo from slight to drastic changes in their dyeing behavior, i.e., rate of dyeing and uptake of acid dyes. Different reaction systems of the same monomer can lead to reverse dyeing properties, indicating not only the function but also the structure affects the properties of grafted silk fab- rics, especially the color-fastness. The UV light graft copolymerization method is of significance in silk industrial applications in terms of the facility cost, operation convenience and grafting efficiency, in comparison to Co 60 γ-ray and electron beam irradiation facilities.
