The Research On Grafting Copolymerization Of Silk Yarns With Complex Monomers

Silk(Bombyx mori) is a kind of material to weave valuable fabrics. Usually, vinyl monomerused to graft silk fibre to improve textile performance,such as frivolousing,crease recovery of sil-k tie and braid fabrics. Methyl acrylamide (MAA) as a common grafted monomer play a role ofcompemsating the silk weight loss caused by scouring process which gained thick,stiff and smo-oth style,and kept their original luster, feeling and whiteness. Although,MAA was an outstandi-ng monomer in silk grafting, after the completion of the reaction there were residual molecularsand polymers distributed in the reaction media.This subject blended MAA and other monomer tografted silk yarn, researched the optimum process of complex systems grafted silk yarn.Then,investigating the range of increased utilization rate of complex systems in the condition of the sa-me monomer mass inputs.The reason of higher utilization rate by studying the reactivity of com-plex systems.Researching founded that methyl methacrylate hydroxyl ethyl ester (HEMA) and three gly-col two methylacrylic acid ester (TEGDMA) grafted silk yarn can obtain higher grafting yield.When m(HEMA/MAA)=3/7, m(TEGDMA/MAA)=1/9, MAA/TEGDMA with the use of the emulsifier0.2g/L, monomer utilization rate increased from62%to70%. Through scanning electron micro-scopy (SEM), which founded that the surface and inside of silk fibre emerged grafted polymers.HEMA and TEGDMA polymer molecular structure of the information reflected in the infraredspectra and amide Ⅰa nd amide Ⅱ characteristic peakdidn’t change, the structure of the silk stillmaintain the beta folding shape conformation. Thermogravimetric analysis in500℃appearedweight loss ratethat also explain TEGDMA and HEMA elements involved in graft copolymeriz-ation.By determination the conversion of the double bond, grafting conversion,graft reaction rateand reactivity ratio of HEMA/MAA, TEGDMA/MAA,applied to analysis of complex systemswith higher utilization ratio.The rate of monomers change to copolymers was quickly at initialstage. HEMA/MAA and TEGDMA/MAA systems had higher graft reaction rate,the peak valueappeared at2min from the beginning of reaction.Whereas MAA grafted silk whit high rate at5 min,which had a lower value. By Estimating the reactivity ratio of HEMA/MAA and TEGDMA/MAA we known that HEMA and TEGDMA more actived than MAA. Composite system hadmore monomer molecules to grafting with silk fibre in the early stage, active higher HEMA andTEGDMA improve the graft reaction rate and conversion rate and improve the utilization ratioof monomers.After grafted with HEMA/MAA and TEGDMA/MAA,the K/S value of acid dyes increasedwith graft yeild,and higher graft yeild made K/S value decline.-NH2in MAA molecules benefitethe improvement of the K/S.High graft yield influenced the penetration of molecular dyes, leadto the K/S value reduced.Grafted polymer had poor substantivity with reactive dyes which leadto K/S value decrease with the increasing of graft yield.