Isocyanate coatings

The curing of two-component Isocyanate coatings appears to be strongly dependent on factors such as catalysis, temperature and relative humidity (8, 9),... 

Water vapour permeability. The most notable phenomenon overlooking the data presented In Table I Is that the water vapour permeabilities of the HMMM-based coatings are not widely different. The Isocyanate coatings show somewhat larger differences. GTG/lsocyanate and the coatings made from butanedlol and neopentyl glycol are more permeable. 

Solvents used for paint removal are able to dissolve or considerably swell physically drying binders (e.g., vinyl chloride copolymers, cellulose nitrate, polyacrylates) and chemically cross-linked coatings (e.g., oil-based paints, dried alkyd resins, cross-linked polyester-melamine resins, cross-linked epoxy and isocyanate coatings) [14.237]. A combination of dichloromethane with low-boiling ketones or esters is particularly suitable. Small amounts of high-boiling solvents with a low volatility (e.g., tetrahydronaphthalene, solvent naphtha, methyl benzyl alcohol, or benzyl alcohol) are added to these mixtures to retard evaporation and increase the solvency. Modern paint removers do not contain chlorinated hydrocarbons, they are formulated on the basis of high boilers (e.g., dimethylformamide, dimethyl sulfoxide, propylene carbonate, and yV-methylpyrrolidone) in combination with alcohols and aromatics, or consist of aqueous, frequently alkaline or acidic systems. 

Uses Catalyst for one-part moisture-cure and two-part isocyanate coatings... 

Blocked isocyanate coating in which the isocyanate has been reacted with a phenol or ketoxime. When the blocked isocyanate is heated, the original isocyanate is liberated and reacts with a polyol present in the formulation to give a very hard polyurethane film. Phenolic vapours, together with traces of the parent isocyanate, are driven off with solvent vapours. 

These performance attributes have contributed to the important role that the two pack acrylic/isocyanate coatings play in the wide range of end use applications including ... 

Typical formulations and characteristics properties for a range of non-isocyanate coatings are given below. A typical white gloss formulation based on the Michael technology might be for heavy duty, rolling stock and heavy equipment enamels ... 

The isocyanate-coated MFC in dry THF could be immediately coated with bisamino-propyl amine or 3-ethylenamino-l-propylamine, thus introducing positive charges to the microfibril surfaces. 

The rapid-scan FTIR technique has been applied to the study of the cure kinetics of isocyanate coatings [51]. The reaction can be followed by monitoring the absorbance of the peak at 2256 cm , which results from the isocyanate functionality, as a function of time. Film thickness can be monitored using the band at 1446 cm . The fractional conversion as a function of temperature and time is calculated by... 

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