Papers by Author: Jin Yan

Abstract: In this paper, the polyurethane prepolymer (Component A) was synthesized with PBA, Castor oil, and IPDI as raw material. The structure and viscosity of PU prepolymer was characterized by IR spectra and rotary rheometer. The thermal performance, adhesion properties and water resistance of cured adhesive films were respectively determined by Thermogravimetric analysis (TG), T-style peel strength test, and water absorption test. The results showed that the addition of castor oil reduced the viscosity of prepolymer and greatly improved the water resistance of cured adhesive, but never affected the thermal performance of adhesive. Besides, castor oil was cheaper, easily obtained and more natural than other polyols. However, castor oil slightly decreased the adhesion strength of adhesive. So the amount of castor oil should be considered.

Abstract: Solvent-free adhesive is a kind of environmental friendly adhesive which is safe, less material consumptive and just needs simple curing conditions. In this paper, the two components solvent-free polyurethane adhesive for flexible packaging was discussed, including its characteristics, composition, curing and adhesion mechanism and three modification methods. The curing mechanism of this adhesive is that crosslinking happens between –NCO and –OH which are contained in two components respectively. However, its adhesion mechanism is different when the adhesive is bonding with polyester film, paper, fabric, metal and other materials. The modification methods of two components solvent-free polyurethane adhesive include modification of its soft segment, modification with epoxy resin and modification with organosilicon and so on. The performance of adhesive can be improved through modification.

Abstract: In this paper, allyl maleated rosin ester was synthesized by the esterification of maleic rosin and allyl alcohol with catalyst. And then a new waterborne paper-plastic composite adhesive was prepared through the semi-continuous emulsion polymerization method with allyl maleated rosin ester, butyl acrylate, vinyl acetate and acrylic acid as raw materials. The product of esterification was analyzed by IR spectra, and its acid value was determined too. Polymer was analyzed by DSC and IR spectra and its T-style peel strength was determined. The adsorption effect of adhesives to ink was also tested. The results showed that this paper-plastic composite adhesive had good adhesive properties: excellent compatibility with the ink, longer stability period, and low cost.