Novel water-dispersible glycidyl carbamate (GC) resins and waterborne amine-cured coatings

Abstract

Water-dispersible glycidyl carbamate (GC) functional resins were synthesized and crosslinked using a water-dispersible amine to form coatings. GC functional resins are synthesized by the reaction of an isocyanate functional compound with glycidol to yield a carbamate (urethane) linkage (-NHCO-) and reactive epoxy group. The combination of both functionalities in a single resin structure imparts excellent mechanical and chemical properties to the coatings. Previous studies on the development of GC coatings have focused on solvent-borne coating systems. In this study, GC resins were modified by incorporating nonionic hydrophilic groups to produce water-dispersible resins. To determine the influence of the content of hydrophilic groups on dispersion stability, aqueous dispersions were made from a series of hydrophilically modified GC resins and characterized for particle size and dispersion stability. The composition of a typical, dispersed GC resin particle was predicted using Monte Carlo simulations. Stable GC dispersions were used to prepare amine-cured coatings. The coatings were characterized for solvent resistance, water resistance, hardness, flexibility, adhesion, and surface morphology. It was observed that GC resins were able to be dispersed in water without using any surfactant and by minimal mixing force (hand mixing) and produced coating films with good properties when crosslinked with a compatible waterborne amine crosslinker.

Glycidyl carbamate functional resins and their applications: a review

“…10). 62 In the study, a series of resins were made using different molecular weight mPEG and different amounts of modification to determine the compositions needed to achieve water dispersibility. Most of the resins synthesized could form stable dispersions on their own and several required the addition of a small amount of surfactant.…”

Synthesis of a waterborne epoxy curing agent based on polyether triols and its application in 2K waterborne epoxy coatings

“…3,4 In recent years, there has been increasing demand to limit the content of VOC in coatings to reduce or eliminate VOC emissions, [5][6][7] and traditional solvent-based coatings have been gradually replaced by environmentally friendly waterborne epoxy coatings. [8][9][10][11][12][13][14][15] Epoxy resin is cured by a curing agent, a dense threedimensional cross-linking network structure can be obtained. [16][17][18] Epoxy resin coatings have excellent corrosion resistance, excellent mechanical properties, and good adhesion, so epoxy resin coatings have a large market share in the field of metal anti-corrosion.…”

“…Conventional solvent‐based coatings lead to a lot of emissions of volatile organic compounds (VOC), which are hazardous to the environment and human health 3,4 . In recent years, there has been increasing demand to limit the content of VOC in coatings to reduce or eliminate VOC emissions, 5–7 and traditional solvent‐based coatings have been gradually replaced by environmentally friendly waterborne epoxy coatings 8–15 …”

Curing mechanism, heat resistance, and anticorrosion properties of a furan/methyl phenyl silicone coating

“…Previous heat‐resistant anticorrosive coatings are mainly inorganic because of abundant raw materials, low cost, and excellent resistance at high temperature. However, they are prone to cracking at high temperature, accompanied by low water resistance before curing and weak adhesion properties . Compared with inorganic coatings, organic ones have satisfactory toughness, adhesion, etc.…”

“…However, they are prone to cracking at high temperature, accompanied by low water resistance before curing and weak adhesion properties. [5][6][7][8][9] Compared with inorganic coatings, organic ones have satisfactory toughness, adhesion, etc. Nevertheless, most organic coatings are solvent systems which are environmentally unfriendly after evaporation, non-heat-resistant, and hardly filmforming, thus limiting practical applications.…”