Preparation And Application Of Plyacrylate Binder Modified With Polysiloxane Containing Fluorine

Pigment printing is a simple and green printing process,which needs no more extra washing and fixation steps.Typically,the desired colored patterns attaching on fabrics are realized by adhering pigments onto fabric surface with binders.Polyacrylate binder has been widely used as a pigment printing binder.However,its film is sensitive to temperatureand has poor water resistance,thus i MPairing the wet rubbing fastness and handle of printed fabrics.Since polysiloxane possesses the characters of flexibility and hydrophobicity,the modification of polyacrylate with polysiloxane can simultaneously improve the properties(especially the wet rubbing fastness and handle)of printed fabrics.On the other hand,fluorine has extremely low surface energy and thus can i MPart the polyacrylate film better water resistance.Therefore,simultaneously inducing polysiloxane and fluorine into polyacrylate can produce a film with strong waterproof and softness,ultimately highly improving the wet rubbing fastness and handle of printed fabrics.The typical modification procedure is described as following: First of all,double-terminated vinyl polysiloxanecontaining fluorine(DVSF)was synthesized.Second,polyacrylate was modified with it.The result was expected that the migration of the fluorine chain could improve the enrichment of the polysiloxane on the film surface,which can provide good water resistance and softness to the latex film,and the color fastness to rubbing and handle of the printed fabric were improved effectively.The followingsare the research contents and results:Part 1: Synthesis and application properties of DVSF.In this part,the DVSF was synthesized by the reaction of octamethyl cyclotetrasiloxane(D4),1,3,5-trimethyltris-1,5-(3,3-trifluoropropyl)-cyclotrisiloxane(D3F)and 1,3-divinyl-1,1,3,3-tetramethyldisiloxane(DVMS)initiated by concentrated sulfuric acid.Then the syntehsized DVSF was used to modify the polyacrylate.The influences of amount of catalyst,reaction temperature and time on the conversion rate were studied.The structure of the DVSF was characterized by FTIR and 1H-NMR.Itsrelative molecular mass was measured by GPC.The modified polyacrylate was used as a novel binder for pigment printing and the printing properties were also tested.The results showed that the optimal conditions for the preparation of DVSF were 0.6 % of catalyst,60℃ of reaction temperature and 6h of reaction time.The FTIR and 1H-NMR characterized that the structure of desired DVSF.The result of GPC showed that the synthesis process was suitable to prepare the DVSF with different molecular weights.The results of printing tests indicated that the color rubbing fastness and handle of the printed fabrics were improved.Part 2: Preparation and characterization of polyacrylate modified with the double-terminated vinylpolysiloxanecontaining fluorine.In this part,the polyacrylate was modified with DVSF via miniemulsion polymerization.The influences of the ratio and dosage of emulsifiers,the dosage and relative molecular mass of DVSF on the properties of the modified miniemulsion and film were studied.And distribution of elements,glass transition temperature(Tg)and thermal stability were also tested by XPS,DSC and TG.The result showed that when the mass ratio of emulsifiers was 1.5:1:1(SDS:O-10:V-20S)and the dosage of compounded emulsifiers was 6%,the emulsion polymerization and stability of emulsion was good,and the film showed the best mechanical property.With the increasing of the amount of DVSF,the water resistance of modified film was enhanced,its breaking strength decreased,the breaking elongation increased,the work of fracture of modified film enhanced at first and then reduced.With the increasing of relative molecular mass of DVSF,the water resistance of modified film was enhanced at first and then reduced,its breaking strength increased,the breaking elongation decreased,the work of fracture of modified film decreased.When the dosage of DVSF was 6%,the relative molecular mass of DVSF was about 6240,the modified film exhibited high ratio of Si/C on the surface of film,well water resistance and the best mechanical property of the film.The result of DSC indicated that the glass-transition temperature of the film was-9.04℃,and dropped co MPared to the film without modification..The result of TG showed that the thermal decomposition temperature of modified film was 457.33℃,and increased about 40℃ co MPared with the origin film,which indicated that DVSF could improve the thermal stability of the film.Part 3: Application of DVSF modified polyacrylate binder for pigment printing.In this part,the DVSF modified polyacrylate was used as a binder for pigment printing.The influences of the amount of binder,curing temperature and time on the color fastness to rubbing and stiffness of fabric were studied.Then the properties of DVSF modified polyacrylate were co MPared with PA binder and polysiloxane modified binder.The result showed that when the dosage of modified binder was 14%,the curing temperature was 160℃,and the curing time was 4 min,the rubbing color fastness to dry of the printed fabric achieved grade 4,the rubbing color fastness to wet of the printed fabric achieved grade 4-5,and stiffness was low,suggesting the a soft handle of printed fabric.Co MPared with PA binder,the rubbing color fastness to dry and wet of the printed fabric were evidently improved,the rubbing color fastness to dry of printed fabric was improved grade 0.5,the rubbing color fastness to wet of printed fabric was improved grade 1-1.5,and handle was improved obviously.Co MPared with polysiloxane modified polyacrylate binder,the rubbing color fastness to wet of printed fabric was improved grade 0.5.Therefore,the performances of DVSF modified polyacrylate binder were better.In summary,the DVSF was successfully synthesized by cationic ring-opening polymerization of D4,D3 F and DVMS.Then the polyacrylate was modified with DVSF and applied for pigment printing.In the film forming process of modified emulsion,the migration of fluorine chains could improve the enrichment of the polysiloxane chains on the film surface,which can improve the hydrophobicity and smoothness of the film,as a result of the improving of the rubbing color fastness and handle of printed fabric.