Abstract: This invention relates to storage-stable, liquid, partially trimerized and allophanized polyisocyanates having an NCO group content of 15 to 41% by weight, and comprising 5 to 85% by weight of toluene diisocyanate, 5 to 85% by weight of a polyisocyanate of the diphenyl-methane series and an organic compound or mixture thereof. The present invention also relates to a process for the preparation of the storage-stable, liquid, partially trimerized and allophanized polyisocyanates; to storage-stable, liquid urethane prepolymers of these partially trimerized and allophanized polyisocyanates; and to a process for the production of these storage-stable, liquid, urethane prepolymers.

Abstract: The present invention relates to a new high functionality MDI. In particular, this invention relates to polymeric allophanates based on diphenylmethane diisocyanate having an NCO group content of 12 to 30%, prepolymers thereof, and processes for the production of these compositions. The prepolymers are stable liquids having NCO group contents of about 10 to about 28%.

Abstract: The present invention relates to a new high functionality MDI. In particular, this invention relates to polymeric allophanates based on diphenylmethane diisocyanate having an NCO group content of 12 to 30%, prepolymers thereof, and processes for the production of these compositions. The prepolymers are stable liquids having NCO group contents of about 10 to about 28%.

Abstract: This invention relates to a continuous process for the production of allophanate modified diphenylmethane diisocyanates having an NCO group content of 19 to 32% and an urethane content of less than 2 area % by GPC analysis. The process comprises (1) continuously reacting (a) diphenylmethane diisocyanate and (b) an alcohol, in the presence of (c) at least 25 ppm of an allophante catalyst, based on the combined weight of the diphenylmethane diisocyanate and the alcohol, in a reactor in an oxygen-free environment; (2) continuously treating the product exiting the reactor with a catalyst stopper at the reaction temperature; and (3) cooling the resultant product.

Abstract: This invention relates to storage-stable, liquid, partially trimerized polyisocyanates having an NCO group content of 24 to 40% by weight, and comprising 20 to 88% by weight of toluene diisocyanate and 12 to 80% by weight of a polyisocyanate of the diphenylmethane series. The present invention also relates to a process for the preparation of the storage-stable, liquid, partially trimerized polyisocyanates; to storage-stable, liquid urethane prepolymers of these partially trimerized polyisocyanates; and to a process for the production of these storage-stable, liquid, urethane prepolymers.

Abstract: This invention relates to a novel trimerization catalyst system, and to a process for trimerizing organic polyisocyanates in the presence of thermally active catalyst systems. These catalyst systems comprise (A) compounds selected from the group consisting of (i) lithium salts of aliphatic or aromatic carboxylic acids, (ii) lithium salts of hydroxyl group containing compounds wherein the hydroxyl groups are directed attached to an aromatic ring, and (iii) lithium hydroxide; (B) an allophanate catalyst; and (C) an organic compound which contains at least one hydroxyl group.

Abstract: This invention relates to a novel freeze-stable allophanate modified toluene diisocyanurates, and to a process for producing these freeze-stable allophanate-modified toluene diisocyanurates which requires a catalyst which is capable of forming both trimer and allophanate groups, or a catalyst system comprising at least one catalyst capable of forming trimer groups and at least one catalyst capable of forming allophanate groups. This invention also relates to novel freeze-stable blends of the allophanate-modified toluene diisocyanurates with di- and/or polyisocyanates of the diphenylmethane series; and to freeze-stable urethane prepolymers of the allophanate-modified toluene diisocyanurates, or the blends of these with an isocyanate of the diphenylmethane series.

Abstract: This invention relates to a novel freeze-stable allophanate modified toluene diisocyanurates, and to a process for producing these freeze-stable allophanate-modified toluene diisocyanurates which requires a catalyst which is capable of forming both trimer and allophanate groups, or a catalyst system comprising at least one catalyst capable of forming trimer groups and at least one catalyst capable of forming allophanate groups. This invention also relates to novel freeze-stable blends of the allophanate-modified toluene diisocyanurates with di- and/or polyisocyanates of the diphenylmethane series; and to freeze-stable urethane prepolymers of the allophanate-modified toluene diisocyanurates, or the blends of these with an isocyanate of the diphenylmethane series.

Abstract: This invention relates to a novel trimerization catalyst system, and to a process for trimerizing organic polyisocyanates in the presence of thermally active catalyst systems. These catalyst systems comprise (A) compounds selected from the group consisting of (i) lithium salts of aliphatic or aromatic carboxylic acids, (ii) lithium salts of hydroxyl group containing compounds wherein the hydroxyl groups are directed attached to an aromatic ring, and (iii) lithium hydroxide; (B) an allophanate catalyst; and (C) an organic compound which contains at least one hydroxyl group.

Abstract: This invention relates to a process for trimerizing organic polyisocyanates in the presence of thermally active catalyst systems. The catalyst systems comprise (a) compounds selected from the group consisting of 1) lithium salts of aliphatic or aromatic carboxylic acids, 2) lithium salts of hydroxyl group containing compounds wherein the hydroxyl groups are directed attached to an aromatic ring, and 3) lithium hydroxide; used in conjunction with (b) an organic compound which contains at least one hydroxyl group.

Abstract: The present invention relates to a process for the production of molded articles via the reaction injection molding technique. According to the RIM process, a reaction mixture is introduced into a closed mold, allowed to react fully, and removed from the mold. More specifically, these reaction mixtures comprise an isocyanate-reactive material, a chain extender, and a stable, liquid diallophanate modified diphenylmethane diisocyanate (MDI). Two specific processes for the preparation of the suitable diallophanate modified diisocyanate are disclosed. These diallophanate modified isocyanates either have an isocyanate group content from about 12 to 30%, or from about 5 to 29%.

Abstract: The present invention relates to a stable, liquid MDI prepolymer containing an allophanate-modified MDI, having an NCO content of 12 to 32.5% comprising a reaction product of an aliphatic alcohol and diphenylmethane diisocyanate comprising about 2 to 60% by weight 2,4'-diphenylmethane diisocyanate and less than 6% by weight of the 2,2'-diphenylmethane diisocyanate, and the rest being 4,4'-diphenylmethane diisocyanate.

Abstract: The present invention relates to a process for the production of a allophanate-modified MDI which is a storage stable liquid at 25.degree. C. comprising (A) reacting (i) one equivalent of a diisocyanate and (ii) one equivalent of an aliphatic alcohol containing from 1 to about 36 carbon atoms or aromatic alcohol containing from 6 to 18 carbon atoms to form a diurethane of the diisocyanate, (B) reacting the product of (A) with 4,4'-diphenylmethane diisocyanate containing from 2 to 60% by weight 2,4'-MDI and less than 6% by weight of the 2,2'-MDI, in an amount sufficient to provide an allophanate having an isocyanate group content of about 12.0 to 30.0%.