Bio-based polyurethane: An efficient and environment friendly coating systems: A review

Synthesis of rigid polyurethane foams with castor oil-based flame retardant polyols

Waterborne polyurethane dispersions synthesized from jatropha oil

Abstract This article is an overview of the chemistry and driers used in autoxidatively cured coatings and in particular alkyds. The drying process for alkyds and other unsaturated fatty acid materials is based on a series of chemical reactions known as autoxidation. The autoxidative process is usually catalyzed by metal salts known as driers. Numerous of investigations have elucidated the catalytic activity and reaction mechanism of the drying process. Spectroscopic techniques, especially mass spectrometry, have been used to study the autoxidation process and its products. Recent investigations on the oxidative drying of alkyd coating films are presented with a focus on both metal based and more environmental friendly means of catalysis.

Review of Autoxidation and Driers

Environmentally friendly waterborne polyurethane (WPU) coatings are used extensively due to their low VOCs emission than solvent based PU coatings. Additionally, WPU coatings have low temperature flexibility, pH stability, water resistance, superior solvent resistance, outstanding weathering resistance and desirable chemical and mechanical properties. This review provides an overview on the recent developments of WPU coatings and their value added applications in the coatings and paint industry. UV-cured WPU coatings provide an important class of green and ecofriendly coatings with outstanding mechanical properties and rapid curing system. Hyper-branched polyurethanes (PUs) show interesting properties, such as high solubility, reactivity and good rheological behavior owing to multiple end groups, compact molecular structure and diminishing chain entanglement. Inherently, WPU coatings have reduced stiffness and mechanical strength that can be increased by the addition of nanoparticles, like Ag, Cu, TiO2, SiO2 and many more. Fire retardants, commonly phosphorous, are incorporated in the WPU structure to increase the flame retardancy of WPU coatings.

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Recent trends in environmentally friendly water-borne polyurethane coatings: A review

Natural castor oil based 2-package waterborne polyurethane wood coatings

Linseed-oil-based waterborne UV/air dual-cured wood coatings

For improving the finishing performances of complicated three-dimensional coated wood products (e.g., furniture) with some shadow zones in the absence of ultraviolet (UV) light, resulting in incomplete curing of UV coatings, the aim of this study was to investigate the characteristics and effects of curing process on the properties of epoxy acrylate UV/PU dual-cured resin for wood coatings when compared with traditional UV and polyurethane (PU) coatings. The epoxy acrylate oligomer was synthesized for providing a double bond of acryloyl group and a secondary hydroxyl group. The UV/PU dual-cured coating was formulated with epoxy acrylate resin/tripropylene glycol diacrylate (TPGDA) monomer by the weight ratio of 80/20, 3% dosage of benzil dimethyl ketal as a photoinitiator, and the NCO/OH mole ratio of 1.0. The aromatic polymeric diphenylmethane diisocyanate was used as a hardener. The films of the dual-cured coating, obtained from UV-cured or room temperature-cured process, showed an excellent tensile strength, elongation at break, impact resistance, and lightfastness when compared with traditional UV and PU coatings; especially, the adhesion of UV/PU dual-cured coating by UV-cured process was better than that of traditional UV coating. It can therefore be concluded that the epoxy acrylate oligomer-based dual-cured coating could readily be used for complicated wood products finishing. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Chia-Wei Chang

Papers

Natural castor oil based 2-package waterborne polyurethane wood coatings

Linseed-oil-based waterborne UV/air dual-cured wood coatings

Epoxy acrylate UV/PU dual-cured wood coatings