Preparation Of Fluorosilicon Modified Polyacrylate And Its Application In Polyester Washing-free Printing

In order to shorten the disperse dye printing process,reduce the discharge of traditional disperse dye printing wastewater,and improve the color yield and color fastness of printed fabrics,a new type of printing process of washing-free printing with disperse dye which had the advantages of water-saving and environmental protection of pigment printing and the excellent color fastness of disperse dyes direct printing was developed in the market.The adhesive played a vital role during the washing-free printing process.However,the common polyacrylate?PA?binder used in washing-free printing process still had many disadvantages.Although the polysiloxane-modified polyacrylate?Si-PA?as binder for washing-free printing process can improve the color yield and dry-wet rubbing fastness of the printed fabric to some extent,but the effect was not satisfactory.Therefore,a fluorine-containing polysiloxane modified polyacrylate adhesive was synthesized to achieve the desired printing effect in this article.The research work was divided in four parts,the study and its result are as follows.The first part:The synthesis and characterization of divinyl terminated fluoropolysiloxane.The divinyl-terminated fluorine-containing polysiloxane was prepared by cationic ring-opening polymerization,with octamethylcyclotetrasiloxane?D4?andmethyltrifluoropropylcyclotrisiloxane?D₃^F?asmonomers,1,3-divinyltetramethyldisiloxane?DVMS?as blocking agent,trifluoromethanesulfonic acid as catalyst.The effects of reaction temperature and reaction time on the yield of synthetic bis-vinyl terminated fluoropolysiloxane were studied,and the synthesis conditions were optimized.The structure of the product was characterized by Fourier transform infrared?FT-IR?spectra and nuclear magnetic?¹H-NMR?,and the applicability of the optimized process for the preparation of fluorosilicone with different molar ratio of fluorine and silicon was investigated.The results showed that the optimal synthesis conditions of the double vinyl terminated fluoropolysiloxane were that the reaction temperature was 65?and the reaction time was 5 h.The yield of the fluorine-containing polysiloxane with different molar ratios of fluorosilicone was above 90%and the actual double bond value was close to the theoretical double bond value,indicating that the reaction technology has better universality applicability.The second part:The preparation and application of fluoropolysiloxane modified polyacrylate emulsion.The fluoropolysiloxane modified polyacrylate?F/Si-PA?emulsion was prepared by a miniemulsion polymerization,with the self-made fluoropolysiloxane and acrylate as comonomers.The polymerization time of the prepared F/Si-PA emulsion was optimized by the appearance of the emulsion and the reaction conversion rate as index value.The reaction conversion rate,gel fraction and emulsion solid content,particle size,and centrifugal/electrolyte stability were determined.The F/Si-PA structure was characterized by Fourier transform infrared spectra.The thermal stability of F/Si-PA was characterized by thermogravimetric analysis.The F/Si-PA emulsion was applied to the washing-free printing,the molar ratio of fluorosilicone and the dosage of the modifier in F/Si-PA were optimized by the color yield and dry/wet friction color of F/Si-PA printed fabric,and compared with the Si-PA and PA printed fabrics.The results showed that when the polymerization time was 2.5-3 h,the appearance of the emulsion was milky blue and the monomer conversion was high.Under these conditions,the reaction conversion rate of the miniemulsion polymerization was over 90%,and the gel fraction was low.The synthesized emulsion with a solid content of 30%had a small particle size,better resistance to centrifugation,electrolyte resistance and thermal stability.The printing application results showed that when the molar ratio of fluorine/silicon of the modifier was 1:10 and the modifier dosage was 9%,the printing performance was the best.The K/S value of the printing fabrics can reach 31.373,the dry/wet rubbing fastness was 4-5 and 3-4 grades respectively,which had better color yield and rubbing fastness than Si-PA and PA printed fabrics.The third part:The study of the mechanism of fluoropolysiloxane modified polyacrylate washing-free printing.In order to investigate the mechanism of fluoropolysiloxane-modified polyacrylate washing-free printing,the hydrophobicity of the surface and interface?film/PET?of F/Si-PA,Si-PA and PA films were analyzed by water contact angle.The content of fluorine and silicon elements on the surface and interface of the F/Si-PA and Si-PA films were analyzed by XPS.The glass transition temperature?Tg?of the three films?F/Si-PA,Si-PA,PA?was tested by DSC and compared with each other.The K/S values of the surface and interface of the three films with the same dye content was measured by Data Color Matching Instrument.The surface morphology of pure polyester fabric and the printed fabric with three kinds of adhesives was characterized by SEM.The water contact angle and XPS analysis indicated that the fluoropolysiloxane migrates to the surface of the film,which was beneficial to improve the hydrophobicity of the film surface.The analytical result of DSC showed that F/Si-PA had a lower Tg than Si-PA and PA,which can promote the diffusion and migration of dyes in the film.The K/S value of the film showed that F/Si-PA facilitated the enrichment of the fluorine-containing polysiloxane segment to the surface,and promoted the migration of disperse dye to the interface of the PET film and F/Si-PA film.The SEM image further confirmed the migration of the disperse dye to the surface of polyester.The fourth part:The application of modified polyacrylate emulsion in disperse dye washing-free printing.The self-made fluoropolysiloxane modified polyacrylate emulsion was applied to the disperse dye washing-free printing.The effects of the amount of modified polyacrylate emulsion,printing baking temperature and baking time on the K/S value of washing-free printed polyester fabric and the color fastness to dry/wet rubbing were discussed,and the process conditions of washing-free printing were optimized.The fluoropolysiloxane modified polyacrylate printing effect was measured and compared with polysiloxane modified polyacrylate and pure polyacrylate.The results showed that when the dosage of the modified polyacrylate emulsion was 14%,baking temperature was 190?,baking time was 3 min,the K/S value of the printed fabric can reach 31.871,and the dry/wet rubbing fastness was 4-5and 3-4 grades respectively.Compared with unmodified polyacrylate and polysiloxane modified polyacrylate,the fluoropolysiloxane modified polyacrylate printed fabric had higher color yield,better dry/wet rubbing fastness,excellent Anti-migration and wash fastness.The research showed that the fluorine-containing polysilane modified polyacrylateemulsionwaspreparedwithself-madefluoropolysiloxane copolymerized and acrylate monomers?EHA,MMA?,and it was applied to disperse dye washing-free printing.Compared with unmodified polyacrylate adhesive and polysiloxane modified polyacrylate adhesive,the prepared fluoropolysiloxane modified polyacrylate adhesive could improve the K/S value and dry/wet rubbing fastness of printed fabric.