Preparation Of Polymerizable Polyurethane Emulsifiers And Polymer Emulsions,and Their Application In Textile And Paper

Acrylic polymers and poly(vinyl acetate)(PVAc)have been widely used as textile dyeing and paper processing auxiliaries due to their advantages of high mechanical strength,good aging and water resistance.Polyurethane(PU)exhibits excellent wear and cold resistance,adjustable hardness,and high adhesion strength,showing certain complementary effect with acrylic polymer and PVAc in performance.Therefore,modifying of acrylic polymer and PVAc with PU would combine the advantages of PU and acrylic polymer(or PVAc),and widen the applications of polymer in textile dyeing and paper processing.Emulsion polymerization is an important method for the synthesis of textile dyeing and paper processing auxiliaries.At present,conventional emulsifiers are mainly applied in the emulsion polymerization process,and several shortcomings,such as desorption from the particles and residues in emulsion,are often occurred.Compared to conventional emulsifier,polymerizable emulsifier contains basic hydrophilic groups and oilphilic groups,and reactive functional groups that can be participated in polymerization.Thus,the polymerizable emulsifier is not only competent for the emulsification process,but also can be covalently bonded to the polymer chains,which can avoid desorption from polymer particles and to prepare stable emulsion with high solid content.In this thesis,a polymerizable nonionic polyurethane emulsifier with comb structure was prepared and employed in the synthesis of polymer emulsion for textile dyeing and paper processing.The application performance of polymer emulsion in textile dyeing and paper processing was investigated.Firstly,comb like polymerizable non-ionic polyurethane emulsifier(PUE)with double bond at both ends,lipophilic main chain and hydrophilic of side chains were synthesized by using hydroxyethyl methacrylate,isophorone diisocyanate,hexamethylene diisocyanate and non-ionic chain extender poly(ethylene glycol monomethyl bismethylolpropane ether)(Ymer N120)as main raw materials.The chemical structure of PUE was characterized by Fourier transform infrared spectroscopy.The critical micelle concentration of PUE was 0.04g/L.PUE showed excellent emulsifying ability to styrene,acrylate and other monomers.Secondly,PVAc emulsion was prepared by using PUE and nonionic emulsifier nonylphenol polyoxyethylene(10)ether(OP-10),respectively.The imitation waxing finishing agent was prepared based on two latexes.It was found that the storage stability and water resistance of PVAc latexes prepared by using PUE were better than that prepared by using OP-10,and the latex stability was increased with the increase of the usage of PUE.The effects of two kinds of emulsifiers on the handle of fabric were investigated from the aspects of toughness,softness and smoothness.It was also found that the imitation waxing finishing agent prepared with PUE was more similar to the original fabric.As the polymer film formed,there is no adhesion phenomenon on the fabric surface.The polymer showed little effect on the original morphology of the fabric fiber and fabric handle.The whiteness of the fabric was slightly decreased,the tearing strength was slightly increased and the color change was not obvious as the usage of PUE increased.The new finishing agent can endow a thick,elastic,fluffy and soft handle style to the fabric,without irritating smell,yellowing,color change and reducing of the fabric strength.So,it has excellent performance and a broad market application prospect.Thirdly,a new printing adhesive was prepared by polymerization of butyl acrylate,styrene and other monomers,using PUE and OP-10 emulsifier,respectively.It was found that using of PUE could obviously improve the stability of the adhesive.Both emulsifiers would affect the color fastness of the printed fabrics.PUE could be fixed to the polymer molecular chain by chemical bond,which reduced the migration of emulsifier.Therefore,the adhesive prepared using PUE could greatly improve the color fastness of printed fabrics.Due to its comb structure,PUE exhibited better water holding capacity,the water migration could be prevented and the mechanical stability of emulsion could be improved.So,PUE could prolong the film forming process.Finally,a new type of paper waterproof agent was prepared by polymerization of butyl acrylate,styrene and other monomers,using PUE and OP-10 emulsifier.It was found that two types of paper waterproof agents could improve the water repellency,the dry and wet tensile of paper,and the waterproof agent prepared by using PUE could improve the above properties of paper more effective than that prepared by using OP-10.On the one hand,the comb structure and polymerizable characteristics of PUE could provided the polymer with stronger binding force with paper fiber and lower migration to water,so the water repellency and adhesive force of polymer on paper fiber was stronger in wet state.