摘要:
A two-component urethane system. The first component is a hydroxy-terminated polyester polyol containing polymerized residues of phthalic acid and an aliphatic diol having Mn from 60 to 150, and having no more than 15 wt % polymerized residues of aliphatic acids. The second component is an isocyanate-terminated prepolymer containing polymerized residues of diphenyl methane diisocyanate and/or toluene diisocyanate and a glycol or polyol having Mn from 90 to 1000.
摘要:
A two-component urethane system. The first component is a hydroxy-terminated polyester polyol containing polymerized residues of phthalic acid and an aliphatic diol having Mn from 60 to 150, and having no more than 15 wt % polymerized residues of aliphatic acids. The second component is an isocyanate-terminated prepolymer containing polymerized residues of diphenyl methane diisocyanate and/or toluene diisocyanate and a glycol or polyol having Mn from 90 to 1000.
摘要:
A one-part, moisture-cure urethane adhesive composition contains between 1 and 10 phr .gamma.-butyrolactone which acts as a moisture diffusion agent, thereby promoting a more rapid cure.
摘要:
A continuous method for the high-yield, one-step, solvent-free manufacture of blocked polyisocyanurate compounds useful as curing agents in powder coating compositions. The preferred method of manufacture is to pre-mix a blocking agent and a polymerization catalyst (BAC mix) prior to injection with an organic isocyanate monomer having two or more isocyanate groups (herein termed a polyisocyanate) into a preheated reaction zone wherein the BAC mix and the polyisocyanate react to form the blocked polyisocyanurate compound that is obtained after discharge from the reaction zone and cooling.
摘要:
In accordance with the present invention, a blocked isocyanate composition which is useful as a curing agent for powder coatings is prepared from the reaction of tetramethylxylene diisocyanate and acetone oxime. In a preferred embodiment, a polyol is reacted with the isocyanate to provide a prepolymer with urethane linkages wherein the isocyanate groups of the prepolymer are substantially blocked with acetone oxime. The blocked isocyanate composition of the present invention can be used as a curing agent for powder coatings, adhesives and high solid coatings which are cured by baking. The blocked isocyanate composition of the invention can be used as a cross-linking agent for a hydroxy-containing polyester, a hydroxy-containing acrylic or methacrylic polymer or any other active hydrogen containing polymer.