| Acrylic emulsion pressure sensitive adhesives do not use organic solvent, without causing pollution to the environment. Now it has been more widely used, but the disadvantage of poor water-whitening resistance limits its application in a number of industries and products. To take the place of traditional solvent-based adhesives, preparation of a good water whitening resistance acrylic emulsion pressure sensitive adhesive is very significant.In this paper, the pre-emulsion technology was used, the influence of the initiator, reactive surfanctant, cross-linking monomer, additional cross-linking agent, particle size, emulsion pH value, molecular weight regulating agent on the emulsion water-whitening resistance were analyzed and discussed. The composition and properties such as FT-IR spectrogram,particle size and its distribution,TEMandDSC, of the latex were characterized.Preparation of the emulsion pressure sensitive adhesive with solid content of 35%, average diameter of particles of 57nm had been made, which can be immersed in 90℃hot water for more than 40 min, loop tack 6#ball, hold tack more than 72h, pell adhesive more than 10 N/25mm, can meet the requirements of some water-whitening resistance labels. Studies show that, used a redox system:initiator A-reducing agent B emulsion pressure sensitive adhesive and used 2% of the reactive emulsifier DNS-86, reduced or eliminated the presence of latex in the water-soluble electrolyte can improve the water whitening resistance of water emulsions. Particle size on the water resistance of acrylic emulsion has great influence, it was found that the average diameter of 57 nm latex, water whitening resistance is better. 1% of the cross-linking monomer GMA or silicone modified Z-6030, and used 0.2% of crosslinker agent SaC-100 or WS-700, have increased cross-linked, used 0.1% of DDM, emulsion pH value of 7~8, these are important factors for good water whitening resistance.
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