摘要:
Products made using the RIM process where the reaction mixture contains an acidic release agent have improved green strength when the reaction mixture also contains a peralkylated polyalkylene polyamine.
摘要:
Disclosed herein is an improved polyurea system comprising a reaction product of a polyisocyanate and a polyamine and an amine chain extender, the improvement comprising the polyisocyanate containing diethyl methylene diisocyanate, a prepolymer thereof or a mixture thereof, in an amount sufficient to slow down the reaction for use in a reaction injection molding.
摘要:
This invention relates to a process for the production of a polyurethane molded part from a reaction injection molding process. The reaction mixture comprises:A) an isocyanate distillation residue resulting from the production of 1,6-hexamethylenediisocyanate by phosgenation of the corresponding amine, followed by the distillation of the pure 1,6-hexamethylenediisocyanate to yield said residue, wherein said residue has an NCO content of from 20 to 27%, a viscosity of from 1500 to 5000 cps at 25.degree. C., and from 0.1 to 3% by weight of hydrolyzable chlorides; withB) an isocyanate-reactive component comprising at least one organic compound having a molecular weight of from 500 to 10,000 and containing at least two isocyanate-reactive hydroxyl groups, and at least one organic diol having a molecular weight of from about 62 to 500,in the presence ofC) a specific catalyst mixture.The catalyst comprises at least one tertiary amine catalyst in combination with another catalyst selected from the group consisting of metal carboxylates, metal halides, ammonium carboxylates, and mixtures thereof.
摘要:
Polyvinyl acetate emulsion based adhesives can be made effective for bonding melamine formaldehyde resin treated decorative solid color and print paper to particle board. This polyvinyl acetate emulsion based adhesive is formulated with tackified polyvinyl alcohol, starch, a tackifier and a coupling agent. Stress cracking is substantially eliminated. Additionally, wrinkling and edge and corner peel resulting during the movement of sheets of melamine resin treated paper on the top and bottom surfaces of sheets of particle board through a heating and pressing zone is substantially eliminated.
摘要:
This invention relates to rigid polyurethanes prepared by reaction, at an isocyanate index of 95 to 110, of(a) an allophanate-modified aliphatic and/or cycloaliphatic polyisocyanurate;(b) 20 to 100% by weight, relative to the total of components (b) and (c), of(i) one or more polyether and/or polyester polyols containing three or more isocyanate-reactive hydroxyl groups and having a molecular weight of 200 to 6000, and(ii) 0 to 30% by weight, relative to component (b)(i), of one or more isocyanate-reactive compounds other than a polyether or polyester of component (b)(i) and containing two or more isocyanate-reactive hydroxyl groups and having a molecular weight of about 400 to about 10,000,(c) 0 to 30% by weight, relative to the total of components (b) and (c), of a chain extender and/or crosslinker other than a polyether or polyester and having a molecular weight of from 32 to 399, wherein the amounts of components (b) and (c) total 100% by weight.
摘要:
This invention relates to a process for preparing polyurethane elastomers comprising reacting in an open mold at an isocyanate index of about 90 to about 110(a) an isocyanate prepolymer having an isocyanate content of about 2 to about 15% by weight and a molecular weight of from about 500 to about 5000 prepared by reaction of(i) at least one organic polyisocyanate with(ii) at least one isocyanate-reactive compound having at least two isocyanate-reactive groups and a molecular weight of from about 250 to about 4000;with(b) certain aminocrotonate-terminated polyethers having a molecular weight of from about 500 to about 1500;(c) optional chain extenders and/or crosslinkers other than aminocrotonate-terminated polyether (b); and(d) optional auxiliaries and/or additives.
摘要:
Storage stable, liquid prepolymers of diphenylmethane diisocyanate containing urea and/or biuret groups are prepared by reacting an aminocrotonate with a mixture of isocyanates having a specified diphenylmethane diisocyanate isomer content. These prepolymers have isocyanate group contents of from about 5 to about 30%.
摘要:
The present invention is directed to a novel internal release agent, a mixture of isocyanate reactive materials containing the release agent and a RIM process using the release agent. The novel release agent is an ester prepared by reacting a specific tetrol with a mixture of a saturated and an unsaturated acid.
摘要:
The present invention relates to a method for adhering two or more substrates by(1) applying to a surface of one of said substrates a non-sagging polyurea adhesive composition comprising the reaction product of:(a) a polyphenyl polymethylene polyisocyanate or a urea-modified prepolymer thereof and(b) an isocyanate-reactive component comprising amines consisting essentially of(i) an aminocrotonate-terminated polyether containing at least two secondary amino groups prepared by reaction of a polyfunctional acetoacetylated polyether polyol with a primary monoamine, and(ii) a low molecular weight aromatic and/or aliphatic diamine, and(2) contacting said substrate with a surface of a second substrate, and(3) curing the polyurea adhesive composition.
摘要:
The present invention relates to a stabilized composition containing a polyol/melamine and an effective stabilizing amount of an amine terminated polyether.