Study On The Preparation, Structure And Properties Of Grafted Silk By ARGET ATRP Method

ARGET ATRP is a new kind of ATRP polymerization system, ARGET ATRP system can significantly reduce the amount of transition metal compounds. This reaction system would not be affected by small amount of oxygen because of the presence of the reducing agent. Accordingly, this method is particularly suitable for aqueous and microemulsions system, which make it be possible for ATRP grafting of silk in the industry.In this study, the macroinitiator was prepared by 2-bromoisobutyryl bromide using dimethyl aminopyridine (DMAP) as catalyst in the presence of acid binding agent triethylamine and then reacted with silk. The bromine content on silk macroinitiator surface was measured by means of surface spectroscopy. The optimal conditions of reaction time, temperature and concentration were determined by single factor experiments.The grafted silk was prepared by ARGET ATRP method using dimethylamino ethyl methacrylate (DMAEMA) and hydroxyethyl methacrylate (HEMA) as monomers, CuBr2 / pentamethyl diethylenetriamine (PMDETA) as catalyst, Vc as a reducing agent, water as medium. The influences of monomer concentration, dosage of catalyst and ligand, reaction temperature, time and pH value on the grafting copolymerization were investigated. The grafting yield - time and conversion rate - time curves indicated that the graft polymerization of DMAEMA and HEMA monomer had the characteristics of living polymerization. The technology of silk grafted by ARGET ATRP and ATRP method were compared, and the result showed that ARGET ATRP grafting process could reduce the dosage of catalyst.The structure of grafted silk was tested by Fourier transform infrared spectroscopy, Raman spectroscopy, X-ray diffraction and scanning electron microscopy. The results showed that DMAEMA and HEMA monomers were successfully grafted onto the silk by ARGET ATRP method. The properties of silk before and after the grafting were investigated, such as strength, whiteness, moisture regain, K/S. It was obtained that the wearability of grafted silk by ARGET ATRP method was not affected.