Modified Bentonite Clay in UV-Curable Coating Applications

Modified bentonite clay was prepared by cationic exchange between the Na+ ions of montmorillonite in bentonite clay and two types of alkyl amines; hexadecylamine (primary amine) and hexadecyl trimethyl amine (tertiary amine). From the XRD analysis it was found that the primary amine-modified bentonite clay provided a greater inter-layer spacing than that with the tertiary amine-modified bentonite clay, although both were significantly higher when compared to the unmodified bentonite clay. The modified clay intercalated structure was then incorporated into a UV-curable coating formulation using epoxidized linseed oil acrylate as an oligomer to form a polymer clay nanocomposite. Energy consumption in the curing process and the physical properties of the cured films were studied as a function of the amount of modified clay incorporated into the coating formulations. The energy consumption in the curing process increased and the hardness and flexibility of the cured films also improved

Water Borne Film-Forming Compositions

The present invention provides a film-forming composition comprising a particulate polymer or emulsified liquid prepolymer, water and a coalescent aid comprising an ester having the formula RCOOX wherein R and X are independently hydrocarbyl or substituted hydrocarbyl, and at least one of R and X contain at least two unsaturated carbon— carbon bonds. The coalescent aid helps lower the minimum film formation temperature of low glass transition temperature coatings and high glass transition temperature coatings and allows optimum film formation at ambient temperatures. The coalescent aid of this coating composition is not volatile like conventional coalescent aids but rather remains part of the film and air oxidizes to cure the film. This coating composition also exhibits properties of adhesion and gloss superior to that of coating compositions containing conventional coalescent aids. Additionally, this coalescent aid can be made from natural or synthetic oils

Preparation of Glycol Esters of Soybean Oil Fatty Acids and Their Potential as Coalescent Aids in Paint Formulations

Soy oil glycol monoesters have been prepared through the transesterification of soybean oil with ethylene, diethylene, propylene, and dipropylene glycols. The molar ratio of soybean oil to glycol used in these reactions was 1∶6. The catalyst used in these reactions was lithium carbonate, 0.5%, based on soybean oil. The transesterifications were carried out at 180-190°C. The composition of soy oil glycol esters and their physical properties were determined. The soy oil glycol esters were incorporated in a water-based paint formulation as the coalescent aid, and the minimum film formation temperature was determined. The minimum film formation temperature results indicated that these esters can be used as coalescent aids in latex paint formulations to help in continuous film formation at or below room temperature

Preparation and Properties of Short Oil Alkyd Resin/TiO2 Nanocomposites Based on Surface Modified TiO2 Nanoparticles

Alkyd resin/TiO2 nanocomposites (NC) were prepared from short oil alkyd resin and TiO2 nanoparticles (NPs) surface modified with in situ formed imine ligand, based on 3,4-dihydroxybenzaldehyde and oleylamine, or with three gallic acid esters. The short oil alkyd resin was synthesized from sunflower oil, phthalic anhydride, and trimethylolpropane. Unmodified and surface modified TiO2 NPs were examined by transmission electron microscopy. Rheological investigation revealed that prepared dispersions have higher dynamic viscosity than pure alkyd resin. Using different characterization methods it was obtained that NCs have similar thermooxidative stability as alkyd resin, lower glass transition temperature, better barrier properties, enhanced hardness, better chemical resistance, and lower adhesion to the metal, except in the case of NC prepared using TiO2 NPs surface modified with imine, which exhibited better adhesion to the metal than pure alkyd resin