Investigation Of Synthesis And Properties Of New Soap-free Polyac Rylate Latex

The traditional polyacrylate emulsion which containing lots of small molecule emulsifiers has negative effects on the water resistance,cohesion and mechanism properties of its film.And the color fastness and handle feeling o f the printed fabric was bad when it was used as fabric pigment printing adhesive agent.In order to solve the problems mentioned above,in this investigation,polymerizable emulsifiers DNS-86 and NRS-135 were applied and a pre-emulsified and semi-continuous adding process was used to the synthesis of soap-free polyacrylate emulsion.With the purposes of further expanding the application performances of its emulsion,organic silicon,organic fluorine and waterborne polyurethane were used as modifier in the preparation of modified soap-free polyacrylate emulsion,respectively.And the soap-free polyacrylate emulsion and its modification emulsion were applied to fabric pigment printing and functional finishing;meanwhile,the properties of the four different soap-free polyacrylate emulsion were investigated.Therefore theoretical guidances for practical application of soap-free emulsion can be provided.In this article,methyl methacrylate(MMA),butyl acrylate(BA),isooctyl acrylate(2-EHA),acrylic acid(AA)and hydroxyethyl acrylate(HEA)were used as the basic monomer in the preparation of the new soap-free polyacrylate emulsion.The influence factors were analyzed and the synthesis parameters were optimized of the preparation of soap-free polyacrylate emulsion through the combination of single factor variable and orthogonal test method.The optimum parameters was as follow: the ratio of polymerizable emulsifiers DNS-86 and NRS-135 was set to 3/2,and its dosage was 0.8%(on weight of total monomers,the same as below),the amount of initiator APS is 0.8%,the ratio of hard and soft monomer was set to 1.32/1,the amount of functional monomer(AA)was 1.2%,the pre-emulsified time was 40 min,while the dropping time of pre-emulsion was 120 min,reacted at 80 ? for 60 min.The vinyl triethoxysilane(KH-151),methacrylic acid dodecafluoroheptyl ester(G04)and homemade waterborne polyurethane was used as modifier in the preparation of modified soap-free polyacrylate emulsion.Single factor variable method was used and the optimum amount of the modifier was determined: the amount of KH-151 was 6%;the amount of G04 was 15%;the amount of waterborne polyurethane was 7.5%.The modified and unmodified soap-free polyacrylate emulsion and its film properties were characterized by infrared spectroscopy(FT-IR),thermogravimetry,scanning electron microscopy(SEM),photoelectron spectroscopy(XPS),dynamic contact angle,particle size and gel permeation chromatography analysis(GPC).The application performance of modified and unmodified emulsion applied in pigment printing and functional finishing was evaluated by rubbing fastness,soaping fastness,handle feeling,surface color depth(K/S values),anti-pilling performance,whiteness,strength,wrinkle resistance,and water resistance.The results showed that soap-free polyacrylate emulsion and modified soap-free polyacrylate emulsion prepared under the corresponding optimum parameters possessing stable physical and chemical properties,ideal emulsion appearance,high solid content,and its application performance in fabric pigment printing and functional finishing was improved.