Study On Acrylate Emulsion And Its Pessure-sensitive Adhesive Odified Via Rosin Derivative And Phosphate Ester

With the ennhangcing of people’s awareness of environmental protection, the researchand application of acrylate emulsion was paied more and more attentions. Acrylate emulsionare widely used in pressure-sensitive adhesive (PSA) owing to its excellent film formingability, adhesion properties and weather durability. However acrylate PSA is flammable and hashigh water absorption ratio and poor adhesive properties to polyolefin substrate, which limitthe scope of its application. Therefore it is significant to modify acrylate emulsion for moreexcellent performance.In this study, the acrylate emulsion modified via radical-polymerizable rosin derivatives(AHR-2-HEA) was prepared successfully through semi-continuous pre-emulsification in-situpolymerization, by using butyl acrylate (BA), and methyl methacrylate (MMA) as monomers,acrylic acid (AA) and hydroxyethyl acrylate (2-HEA) as functional monomers, potasslumpersulfate (KPS) as intiator, and allyloxy nonylphenol polyoxyethylene (10) ether ammoniumsulfate (DNS-86) as reactive emulsifier. The modified acrylate emulsion was crosslinked withsilicone-9301as curing agent and corresponding pressure-sensitive adhesive was prepared.The effects of AHR-2-HEA on polymerization process and PSA adhesion properties werestudied. The bicyclic caged phosphate (PPPC-HEA) was synthetized. The acrylate emulsionsmodified by reactive phosphates were prepared and blended with aryl phosphate (BDP) tomake flame retardant PSA. The effects of amount of phosphates on polymerization process,PSA adhesion properties and flame retardancy were discussed.The main research content and results are listed as follows:(1) The effects of the amount of DNS-86, KPS and AHR-2-HEA, the mass ratio ofMMA/BA and AA/BA on the monomer conversion, coagulum ratio, diameter and viscosityof the acrylate emulsion modified via rosin derivatives were studied. The latex and its filmwere characterized by Dynamic Light Scattering Nano-Particle size Analyzer (DLS), FourierTransform Infrared Spectroscopy (FT-IR), Thermo-Gravimetric Analysis (TGA) andDifferential Scanning Calorimetry (DSC). The results showed that DNS-86and AHR-2-HEAdid participate in copolymerization. With the increase of the amount of AHR-2-HEA from0to10wt%, the conversion reached to97%, and the latex particle diameter showed a bimodal distribution with the peaks shifting to the large particle region;. TGA results showed thatAHR-2-HEA could improve the thermal stability of the latex film. DSC analysis showed thatthe compatibility between AHR-2-HEA and systems was good.(2) Acrylate pressure-sensitive adhesive (PSA) was prepared by using silicone-9301ascuring agent. The effects of the amount of silicone-9301and AHR-2-HEA, the mass ratio ofMMA/BA and AA/BA on adhesion properties of the PSA were discussed. The resultsshowed that the cohesive strength and the water resistantce of latex film could be improvedafter curing. With the increase of the amount of AHR-2-HEA from0to10wt%, thewettability of PSA to substrate improved, and initial tack increased,180°peel strengthincreased first and then decreased. PSA had optimal combination property, that its initialtack was10#steel ball,180°peel strength was670N/m and hold tack exceed72h when massfracion of AHR-2-HEA was8wt%.(3) Bicyclic caged phosphate (PPPC-HEA) was synthetized. The acrylate emulsionsmodified via PPPC-HEA, APE-2005and V-100P which were commercially available wereprepared successfully. With the increase of the amount of phosphates, the conversion andhold tack decreased, initial tack and180°peel strength increase first and then decreased.PPPC-HEA flame retardant properties was superior to the APE-2005and V-100P, but theadhesive properties of PSA modified via PPPC-HEA was decreased more. TGA resultsshowed that the initial decomposition temperature of the acrylic latex film modified viaphosphates were decreased, but the residual carbon content were improved when comparedwith pure acrylic latex film.