Preparation and Application of Polyurethane Coating Material Based on Epoxy Cyclohexane Protective for Paper

Paper is important to most historical and cultural relics, however, these paper heritages are facing a crisis of disappearance, damage and aging. For increasing the paper strength, delaying the paper aging, and improving the weak stability and permeability of former resins used for paper, another material is necessary to be produced on preservation and protection of the paper items. The synthesis of epoxy cyclohexane polyetherpolyol was as follows: Epoxy cyclohexane was as the starting material, ethylene glycol was as the initiator, boron trifluoride ether was as catalyst, and dichloromethane was as the solvent. The synthesized homopolyether was characterized by infrared (IR) spectroscopy and proton nuclear magnetic resonance (1HNMR) spectroscopy to determine the structure. Then the epoxy cyclohexane homopolyether reacted with the hexamethylene diisocyanate (HDI) trimer, and the polyurethane was obtained. With the tests of the physical and chemical properties of paper samples, it showed that the paper processed with 10% polyurethane liquid had excellent performance, the increase in the tensile strength was from 1105 to 2317 N/m, and the increase in the folding endurance was from 20 to 504 times. What’s more, the paper processed with 10% polyurethane liquid had good brightness and gloss. The results of the paper samples for the test have shown that the synthesized material simultaneously has the advantages of epoxy cyclohexane homopolyether and polyurethane, possessing excellent performance in paper reinforcement. Thus, the synthesized polyurethane material has broad application prospect in paper protection field.