Synthesis And Properties Of Self-emulsifying Acrylate Dispersions

In recent years,the voice of environmental protection in all walks of life is getting louder and louder.In the printing industry,the development of water-based ink has become the general trend.Binder as the most core component of ink,plays a decisive role in the performance of ink,so the core work in the field of water-based ink is the structure design and performance study of the water-borne binder.At present,the water-based ink prepared with acrylate dispersion has been successfully applied in cigarette label printing industry.The current production methods of acrylate dispersion are basically the route of solution polymerization.There are many problems,such as large amount of organic solvent in the production process,high demand for equipment,high energy consumption and difficult removal of residual solvent in the last process via vacuum technology.In this paper,emulsion polymerization route was used to study the preparation of acrylate dispersion with high solid,low viscosity.The performance of the dispersion as a linker used in cigarette label printing water-based ink was investigated.The main work of this paper is as follows:1.The effect of the chain transfer agent,initiator,polymerized temperature on the molecular weight of the polyacrylate,as well as the effect of molecular weight,dosage and kind of the hydrophilic group,types and degree of neutralization of alkali neutralizer on the viscosity,solid content,transparency and other performance of the polyacrylic dispersion were studied in detail.It was found that the smaller the molecular weight of the resin,the lower the viscosity of the dispersion and the better the transparency of the dispersion while keeping the solid content unchanged.The higher the amount of carboxyl group introduced by hydrophilic monomer and the more carboxyl group distributed in the outer layer of latex particles,the higher the viscosity and the lower the solid content of the dispersions can be prepared.The type and dosage of alkali neutralizer have a great influence on the viscosity and transparency of the dispersion,in which N-methyldiethanolamine not only avoids the pungent smell of ammonia,but also can give the dispersion low viscosity and high transparency.2.The influence of carboxyl content,monomer,emulsifier and other factors on dispersion performance,including the abrasive resistance of pigment dispersion ability and the stability of ethanol resistance was studied.It was found that the higher the carboxyl group content,and the more carboxyl groups distributed in the outer layer of latex particles,the better the dispersion ability of the resin to pigment,the better the abrasive resistance and the better the stability of ethanol resistance;the type of monomer also has a great influence on the viscosity of the dispersion,and ethyl acrylate(EA)and vinyl acetate(VAc)have better viscosity reduction effect on the dispersion than isobornyl acrylate(IBOA).3.The water-based inks were prepared using acrylate dispersions as binder.Based on the study results on the properties of the ink,such as resolubility,drying rate on the tobacco packet substrate,and other properties,an optimized dispersive formula was obtained:SDS dosage of 2.5wt%,EA dosage of 30wt%,VAC dosage of 15wt%,hydrophilic monomer MAA dosage of 5wt%and NDM dosage 2.5wt%.