Research Of Reactive Dye Printing Paste Based On Acrylic Polymerization

With the advantages of high quantity of color and bright color etc., Sodium alginate haslong been used as the reactive dye printing directly paste. However, as the innovation of printingtechnology, sodium alginate’s shortcomings have been exposed in flat screen and rotary screenprinting, and the price is also rising in recent years. Searching for the suitable substitutes is thepresent problem in urgent need to be solved in the reactive dye printing field.In this paper the octadecyl methacrylate and lauryl methacrylate were adopted to modifypolyacrylic acid sodium, and obtained the hydrophobic association electrolyte resistant syntheticthickener in the first place. Then the acrylic acid, low substitution degree of carboxymethylcellulose (CMC) and starch were used as raw material to prepare polysodium acrylate/CMCcomposite paste and polysodium acrylate/starch composite paste by polymerization. Theirpreparation technology was optimized and the structure and the paste properties werecharacterized in this issue. Then the product prepared were used for reactive dye printing and theprinting effects were compared with sodium alginate, sodium polyacrylic acid andcarboxymethyl cellulose respectively. The results show that:Optimizing the inverse emulsion preparation process of polyacrylic acid sodium, theconversion rate of acrylic acid is more than92%, and3%the original paste’s viscosity is13667mPa·s, PVI value is0.26, property of holding water is1.7mm and the viscosity retention rate isonly10.5%. The octadecyl methacrylate and lauryl methacrylate monomers were added duringthe preparation of polyacrylic acid sodium. When the total amount of combination of monomeraccounts for4%~5%, octadecyl methacrylate and lauryl methacrylate mass ratio is1:3, theviscosity of3%prepared hydrophobic association thickener paste is10667mPa·s, PVI value is0.26, property of holding water is1.8mm and the viscosity retention rate is up to40%. Therheological property, thixotropy, storage stability, property of holding water, viscosity andviscosity index are better than those of sodium alginate, but the chemical compatibility remainsto be improved. The FTIR analysis shows that hydrophobic monomers participate in the reactionand the reaction is completed. The thermal analysis shows that the thermal stability of the modified synthetic thickening agent is nearly same as sodium polyacrylate, and won’t be brokenin the steam.The preparation process of polysodium acrylate/CMC composite paste and polysodiumacrylate/starch composite paste were optimized. The viscosity of1%prepared sodiumpolyacrylate/CMC composite paste is2567mPa·s, PVI value is0.483, property of holding wateris4.3mm. And the viscosity of1%prepared polyacrylic acid sodium/starch composite paste is6433mPa·s, PVI value is0.273, property of holding water is9.26mm. The rheological property,thixotropy,storage stability, property of holding water, viscosity and viscosity index are betterthan those of sodium alginate, but the chemical compatibility remains to be improved, and theprepared compound paste could be used for reactive dye printing without purification. The FTIRanalysis and carboxyl content test show that compared with the original CMC, the hydroxylcontent of polyacrylate sodium/CMC composite paste reduces and the carboxyl content increases.Meanwhile acrylic monomer is grafted onto starch successfully. The thermal analysis shows thatthe thermal stability of the two kinds of prepared compound paste is good, and could not bebroken in the steam. The X-ray diffraction (XRD) analysis shows that the crystal structure of thepolyacrylate sodium/CMC composite paste is not different from the original CMC, but therelative crystallinity increases. Compared with starch, the crystal structure of the polyacrylatesodium/starch composite paste changes, but the relative crystallinity reduces.The printing performance of the prepared three kinds of paste above was tested, the printingcolor quantity of polyacrylic acid sodium/starch composite paste is the best and the permeabilityis excellent, but the rate of removing paste and the feel of the textiles perform not well. Theprepared polysodium acrylate/CMC composite paste’s rate of removing paste, the feel of textilesand color fastness are optimum, also the amount of color performance, the permeability etc., arebetter than those of the CMC, and amount to SA. The amount of color and the color fastness ofthe hydrophobic association thickener paste are improved better than that of PAA, and are nearlysame as the SA, but the rate of removing paste and the feel of the textiles remain to be improved.