Abrasion-resistant and low friction coating compositions

A method of using a prepolymer polymerized from oxetane monomers to form a lubricous, abrasion resistant coating composition comprising:

• (a) reacting an excess of a diisocyanate with a hydroxyl terminated prepolymer to produce an isocyanate terminated polymer having urethane links, wherein said excess is characterized by an NCO:OH ratio of at least 2, at least 5 percent by weight of said isocyanate terminated polymer being one or more repeat units of the structure ##STR9## and wherein said repeat units are formed from one or more oxetane monomers and further wherein R is H or an alkyl of from 1 to 6 carbon atoms;
• and Rf individually on each repeat unit is a linear or branched alkyl of 1 to 20 carbon atoms, a minimum of 75 percent of the H atoms of said R.sub.f being replaced by F and optionally up to all of the remaining H atoms being replaced by I, Cl or Br;
• or each Rf individually being an oxaperfluorinated polyether having from 4 to 60 carbon atoms, and n is from 1 to 5,
• (b) chain extending said isocyanate terminated polymer having urethane links by reacting said isocyanate terminated polymer of (a) with a poly(alkylene oxide) polyol, a poly(ester) polyol, or a hydroxyl terminated hydrogenated diene polymer or combinations thereof forming a coating composition, and
• (c) optionally blocking unreacted isocyanate groups in said coating composition.

A structure adapted to sealingly interact with a movable window comprising an elastomeric portion having a lubricous, abrasion resistant coating on those portions thereof that contact with said window, wherein said coating is made by a process which comprises:

• (a) reacting an excess of a diisocyanate with a hydroxyl terminated polymer to produce an isocyanate terminated polymer, wherein said excess is characterized by a NCO:OH ratio of at least 2, at least 5 percent by weight of said isocyanate terminated polymer being one or more repeats units of the structure ##STR11## and wherein said repeat units are formed from one or more oxetane monomers and further wherein R is H or an alkyl of from 1 to 6 carbon atoms;
• and Rf individually on each repeat unit is a linear or branched alkyl of 1 to 20 carbon atoms, a minimum of 75 percent of the H atoms of said Rf being replaced by F and optionally up to all of the remaining H atoms being replaced by I, Cl or Br;
• or each Rf individually being an oxaperfluorinated polyether having from 4 to 60 carbon atoms, and n is from 1 to 5,
• (b) chain extending said isocyanate terminated polymer by reacting with a poly(alkylene oxide) polyol, polyester polyol, or a hydroxyl terminated hydrogenated diene polymer or combinations thereof forming a chain extended product,
• (c) optionally blocking unreacted isocyanate groups in the product of (b)
• (d) applying the chain extended product of (b) or (c) to said structure adapted to sealingly interact with a movable window and curing the chain extended product.