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

Abstract

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.

The kinetics of uncatalyzed and catalyzed urethane forming reactions of aliphatic diisocyanates with butan-1-ol

“…Polyurethanes (PURs) are one of the most important and versatile classes of polymers produced by step-growth polymerization taking place between isocyanates (aromatic and/or aliphatic) and alcohols. 1 The wide variety of isocyanates and polyols makes it possible to tailor the properties of the resulting PURs for certain applications spanning from coatings 2,3 through various types of foams and elastomers 4 to biomedical devices and accessories. 5 Depending on the targeted properties, both aromatic and aliphatic isocyanates are frequently used in the production of various PURs.…”

Preparation and Application of Polyurethane Coating Material Based on Epoxycyclohexane-Tetrahydrofuran in Paper Conservation

“…At each mass concentration, the tearing strength of paper in homopolyetheryl-based polyurethane coating was lower than that in copolyether-based polyurethane coating. In addition, the gloss and brightness were affected little by the synthetic polyurethane [19,25]. Generally, copolyether-based polyurethane performing in similarity is preferable in the influences of polyurethane solution upon the paper.…”

“…Tensile strength, elongation, folding endurance, and tearing strength of paper were detected as the mass concentration variation of polyurethane [18,19]. As shown in Figure 6a, with increasing mass concentration, tensile strength increased from 1105 to 3616 N/m, with a growth rate of 227%.…”

“…Based on the proportional control of rigid and flexible segment, rigidity and molecular weight of copolyether are adjustable as required [17]. In addition, as a steric hindrance effect of cyclohexyl, polyurethane is disordered, transparent, and not easily crystallized [17][18][19]. Polyurethane coating based on CHO-THF presents high gloss and solvent resistance [17].…”

Preparation and Application of Polyurethane Coating Material Based on Epoxycyclohexane-Epoxychloropropane Protective for Paper

“…Coupled with its large steric hindrance, the synthetic polyether molecular chain is disordered, transparent, and not easy to crystallize. Meanwhile, for the linear structure of epoxychloropropane, the hardness of copolyether decreases and the fluidity increases [17][18][19]. At the same time, the introduction of a chlorine atom in epoxychloropropane will give polyurethane some new properties, such as flame retardancy and good adhesive properties [20].…”