Abstract:
Provided are one-part, shelf-stable polyurethane aerosol compositions, and related articles and methods. When sprayed onto a substrate and dried, these compositions provide polyurethane films. These polyurethane films display improved moisture resistance, optical clarity, and weatherability compared to known aerosol compositions, particularly in adverse environmental conditions. The compositions generally include an aqueous polyurethane dispersion containing a urethane moiety obtained by reacting (i) a polyol or thiol having isocyanate-reactive functional groups, (ii) a neutralized water-solubilizing compound, and (iii) a diisocyanate and optionally a silane terminal group; a propellant; and optionally one or more additives.
Abstract:
A perfluoropolyether thiol compound comprises a perfluoropolyether segment, at least one mercapto group (—SH), and at least one intervening divalent carbonylimino moiety (—C(═O)—NR—, wherein R is hydrogen or alkyl). The compound can be produced, for example, by a ring-opening reaction of thiolactones with perfluoropolyether-substituted, primary or secondary amines. The compound can be used, for example, as a polymerization chain transfer agent, as an intermediate for the preparation of functional group-containing fluorochemical derivatives such as disulfides, and as a fluorinated surface treatment.