A Study On Mercapto Click Chemistry And Its Application On Keratin Fibers

In recent years,people have put forward higher and higher requirements for the green and clean chemical production process.As for the future development of functional textiles,it is important to explore a facile,clean and durable finishing method.Click chemistry is one kind of new chemical reaction which is efficient,mild and clean.It meets the satisfy requirements for green production.At the same time,functional finishing agents covalently bonded to the substrate surface,which will allow the material to carry semi-permanent or even permanent functionality.Therefore,this paper intends to use click chemistry as a new method to modify textiles,which may alleviate the industrial pollution and improve the fastness between fabric and finishing agent.Specifically,the antibacterial quaternary ammonium salts will covalently bind to the surface of the proteinaceous textile via click chemistry.In this paper,we treated the surface of wool with a thiols reducing agent tris(2-carboxyethyl)phosphine hydrochloride(TCEP)to reduce the disulfide bonds on the surface of the wool to thiol groups firstly.Then,three kinds of quaternary ammonium salts(GTAC,DADMAC and IDMA)with different functional structures were used to modify the wool surface by click chemistry.The first type of reaction is a nucleophilic ring opening reaction with an epoxy structure.The reaction was carried out under 40 ? for 8 h with the solution p H of 8.0.The second type of reaction is the addition reaction for carbon-carbon multiple bonds.The reaction was carried out under UV irradiation for 2 h with room temperature.The third type of reaction is thiol-ene click chemistry combining with a step-growth dithiol-diacrylate reaction.The reaction was carried out under 25 ? for 18 h with the solution p H of 8.0.The results demonstrated that these three kinds of reactions could graft the antibacterial quaternary ammonium salts on the wool surface and impart the wool fabric with good antibacterial properties and some other excellent physical and chemical properties.In addition,the second type of reaction is difficult to occur under conventional conditions.It is necessary to add photoinitiator in the reaction system and react under UV irradiation.In this paper,2,2-dimethylolpropionic acid(DMPA),a water-solublecompound,is used as the photoinitiator for this reaction.The reaction system only requires deionized water as the solvent,therefore,the experimental process is very green and clean.The antibacterial efficiency of GTAC treated sample is 99% and the antibacterial efficiency of GTAC treated sample after 30 cycles of standard washing can still maintain 95%.The antibacterial efficiency of DADMAC treated sample against E.coli and S.aureus are both over 99%.In addition,it could be maintained at 99% after 30 cycles of standard washing.The antibacterial efficiency of IDMA-SP treated sample against E.coli and S.aureus are both over 97% and it became 90% after 30 cycles of standard washing.The results also showed that the hydrophilicity and antistatic property of the wool fabric were improved obviously because of the hydrophilic quaternary ammonium salts.