The Preparation Of The Polyurethane Acrylate Emulsion Applied On The Textile Inkjet Printing

Inkjet printing as a possible way to substitute traditional printing with high precision and personalized customization can be achieved.Among them,the application of paint-based inkjet printing ink was the hot spot in the field of inkjet printing.In this paper,the waterborne polyurethane acrylate resin was used as the binder for the preparation of inkjet printing ink.The copolymer of the waterborne polyurethane and the acrylic ester was discussed,and the complex with curing agent was also discussed.Firstly the waterborne polyurethane(WPU)emulsion with different initial R value,dimethylolpropionic acid(DMPA)content and cross-linking degree were synthesized using isophorone diisocyanate(IPDI),polycarbonate diol(PCDL),DMPA and hydroxyethyl acrylate(HEA).The factors influencing the properties of the WPU were discussed.The effects of various factors on the particle size,viscosity,mechanical properties and water resistance of the WPU were analyzed.The experimental results showed that the optimal experimental conditions were as follows: the initial R value was 1.8,the dosage of DMPA was 4.5% and the dosage of TMP was 1.2%,The viscosity of the WPU was 10-200 m Pa·s and the particle size was 80-200 nm.Secondly the core-shell structure waterborne polyurethane acrylate(WPUA)was gianed in the condition of soap-free emulsion polymerization.The WPUA gained the flexibility of polyurethane and the resistance of acrylic weather.The core-shell hetero-phase structure can effectively improve the mechanical properties of the film without changing the composition and dosage of raw materials.The properties of the emulsion and film were characterized by FTIR,TGA,particle size analysis and surface tension analysis.The experimental results showed that the optimal experimental conditions was that the azobisisobutyronitrile(AIBN)was selected as initiator,the mass ratio of acrylate and WPU was 0.4,and the reaction temperature was 80 ?.Compared to the WPU film,the tensile strength of WPUA film increased to 3.6 MPa,the elongation at break increased to 293%,the water absorption was 17.9%,the emulsion viscosity was 10-200 m Pa · s,the particle size distribution was 80-200 nm.The modified WPUA was non-Newtonian fluid properties and suitable for inkjet printing.Lastly,the aziridine was selected as the curing agent to improve the properties of the film according to the nature of the WPU.The effect of curing time,curing temperature and aziridine dosage on the properties was discussed.The result showedthat when the curing temperature was 100 ?,the curing time was 30 min,on this condition the film was completely cured.The pencil hardness of the film was 1H,the tensile strength of film was 4.2 MPa,the water absorption was 10.5% and the elongation at break increased was 265%.The aqueous polyurethane acrylate copolymer was prepared by means of soap-free emulsion polymerization.The innovation of this paper lies in the graft copolymerization of the aqueous polyurethane terminal vinyl group and the acrylic ester monomer under the action of AIBN.Then the WPUA compound aziridine curing agent,explored its film properties for the development and application of new products to provide a theoretical basis.