The Synthesis And Application Of Polyacrylate Latex Modified With Double Terminated Acryloyloxy-propyl Polysiloxane

Pigment printing was a kind of clean production techniques of printing for achieving the purpose of the coloring process by the way of particle of pigment adhesion on the fabric using adhesive. Adhesive agent was an important part of the pigment printing paste, the handle and fastness of the pigment printing product was affected directly by its quality. At present, adhesive agent for pigment printing was polyacrylic acid esters mainly, but it has some defects such as poor water resistance and stain resistance of latex film, hot sticky-cool brittle performance of the film, and there are contradiction between handle and color fastness of printed fabric, which limited the popularity and development of pigment printing. Polysiloxane was widely used to modify pigment printing adhesive agent for its soft quality, low surface energy and biological inert etc. Polyacrylate modified with polysiloxane had good water resistance, good stain resistant and good permeability, it attracted the attention of people in the recent years. Therefore, double terminated acryloyloxy-propyl polysiloxane (diAOp-PDMS) was synthesized at first, and used to modify polyacrylate for making a new kind of pigment printing adhesive agent with good crocking fastness and handle. This paper was divided into three parts:Part1:Synthesis and characterization of double terminated acryloyloxy-propyl polysiloxane.In this part, a double terminated acryloyloxy-propyl polysiloxane (diAOp-PDMS) was prepared by acylation reaction with acryloyl chloride and double terminated hydroxy-propyl polysiloxane as raw materials. The influences of reaction factors such as reactant ratio, reaction temperature and time and dosage of solvent on the product rate were investigated, and the structure of product was characterized by FTIR and1H-NMR. The results showed that the optimal esterification condition was that acryloyl chloride was the2.4times of double terminated hydroxy-propyl polysiloxane, reaction temperature was35℃and reaction time was3h, the amounts of solvent was40%,the product rate reached79%. FTIR and1H-NMR analysis indicated that the structure of product was double terminated acryloyloxy-propyl polysiloxane. Part2:The synthesis and properties of polyacrylate latex modified with double terminated acryloyloxy-propyl polysiloxane.Polyacrylate latex was modified by the pre-emulsification semi-continuous emulsion polymerization with double terminated acryloyloxy-propyl polysiloxane as modifier, and the modified polyacrylate latex was applied in pigment printing. The effects of addition methods of organic silicon modifying monomer,and its amounts on the properties of silicone modified polyacrylate latex and latex film were studied, the influence of molecular weight of polysiloxane in the diAOp-PDMS, and the amounts of diAOp-PDMS on the properties of organic silicon modified polyacrylate latex, latex film and pigment printing were studied, the structure and properties of modified polyacrylate latex were analyzed by FTIR, water contact Angle analyzer, particle size analyzer, and the thermo-gravimetric analyzer. The results showed that the method of diAOp-PDMS and acrylic monomers mixing emlusion polymerization could effectively increase the stability of the emulsion polymerization. The higher molecular weight of polysiloxane was, the worse emulsion stability and film water resistance were, the poorer properties of pigment printing was. When organic silicon modifying monomer was added by being mixed with acrylic monomer, and its amount was8%～10%, the monomer conversion of emulsion polymerization was higher, the agglomerate rate was lower; the particle size of emulsion was about62nm and its distribution was narrow; the modification film had low water absorption, and higher fracture work; and the pigment printing fabric with modified polyacrylate latex had good color fastness and soft handle. It was comfirmed that organic silicon monomer was grafted into polyacrylate molecular chain by FTIR.Part3:Research on the application of double terminated acryloyloxy-propyl polysiloxane modified polyacrylate for pigment printing binderIn this part, the polyacrylate latex modified with double terminated acryloyloxy-propyl polysiloxane was used in pigment printing, the influences of pigment printingfactors such as amounts of organic silicone modified polyacrylate latex binder, curing temperature and curing time on properties of pigment printing for cotton fabric were studied, the pigment printing process conditions were optimized, the performance of pigment printing was tested, and compared with that of unmodified polyacrylate binder and polyacrylate latex modified with double terminated acryloyl-polyether polysiloxane pigment printing binder. The results showed that when the binder was16%, curing temperature was160℃, curing time was4min, the printed fabric had good handle, and dry rubbing fastness and wet rubbing fastness can reach grade4grades. Compared with unmodified polyacrylate binder, the wet rubbing fastness of the printed fabric was higher1grades, Compared with polyacrylate latex modified with double terminated acryloyl-polyether polysiloxane pigment printing binder, the wet rubbing fastness of the printed fabric was higher0.5grades, and the printed fabric had better handle, basically achieved the objective unification of handle and fastnes.The results of research showed that polyacrylate latex modified with double terminated acryloyloxy-propyl polysiloxane by semi-continuous emulsion polymerization could be used as pigment printing binder with good rubbing fastness,especially wetting rubbing fastness, the dry and wet rubbing fastness of the printed fabric reached4grades, and the printed fabric had better handle, basically achieved the objective unification of handle and fastness.