摘要:
This invention relates to a new modified silicate composition prepared by the reaction of an alkyl silicate or its oligomer with a specified active hydrogen compound in a specified ratio and to a method of producing a sand mold therefrom. More particularly the invention relates to an improvement in the production of a sand mold by using an organic binder and a hardener therefor, and a ceramic binder and a hardener therefor to produce economically a mold having an excellent strength without resort to complicated procedures.
摘要:
A polyisocyanate composition comprising at least one polyisocyanate compound selected from the group consisting of diphenylmethane diisocyanate oligomers containing 20 to 60 wt % of diphenylmethane diisocyanate and derivatives of said oligomers and, dissolved or dispersed therein, from 0.1 wt % to less than 10 wt % of a silicate compound. The composition is remarkably excellent in low-temperature storage stability.
摘要:
A reaction product of a tetraalkoxysilane or a silicate oligomer obtained by the partial hydrolysis and dehydrating polycondensation of the same with an amino alcohol having one or two hydroxyl groups. It is suitable for the dehydration of a moisture of about several hundreds of ppm, and especially suitable for use as a dehydrating agent for the raw materials employed for the preparation of a urethane resin and an epoxy resin, because it produces an amino alcohol by the dehydration.
摘要:
A reaction product of a tetraalkoxysilane or a silicate oligomer obtained by the partial hydrolysis and dehydrating polycondensation of the same with an amino alcohol having one or two hydroxyl groups. It is suitable for the dehydration of a moisture of about several hundreds of ppm, and especially suitable for use as a dehydrating agent for the raw materials employed for the preparation of a urethane resin and an epoxy resin, because it produces an amino alcohol by the dehydration.
摘要:
Storage stable high reactive polyisocyanate composition capable of withstanding a wide range of storage and handling conditions contain from 30 to 500 ppm of an organometallic based urethane catalyst and from 30 to 10,000 ppm of an acyl chloride compound based on the polyisocyanate compound. The composition can be utilized effectively in various spot applications such as spray foaming, painting for water-proofing, floor painting and paving, or the production of various polyurethane resins or foams.
摘要:
[Construction] A polyisocyanate composition comprising diphenylmethane diisocyanate oligomer and from 40 to 62 weight percent based on the total polyisocyanate of diphenylmethane diisocyanate or a derivative thereof, wherein the composition also comprises from 0.0001 to 4 parts by weight per 100 parts by weight of polyisocyanate of a denatured silicone oil which is inactive to the polyisocyanate. [Advantages] A polyisocyanate composition according to the present invention has excellent storage stability at low temperature and can be effectively used in the production field of polyurethane resins.
摘要:
[Construction] A polyisocyanate composition comprising diphenylmethane diisocyanate oligomer and from 40 to 62 weight percent based on the total polyisocyanate of diphenylmethane diisocyanate or a derivative thereof, wherein the composition also comprises from 0.0001 to 4 parts by weight per 100 parts by weight of polyisocyanate of a denatured silicone oil which is inactive to the polyisocyanate. [Advantages] A polyisocyanate composition according to the present invention has excellent storage stability at low temperature and can be effectively used in the production field of polyurethane resins.
摘要:
This invention relates to a new modified silicate composition prepared by the reaction of an alkyl silicate or its oligomer with a specified active hydrogen compound in a specified ratio and to a method of producing a sand mold therefrom. More particularly the invention relates to an improvement in the production of a sand mold by using an organic binder and a hardener therefor, and a ceramic binder and a hardener therefor to produce economically a mold having an excellent strength without resort to complicated procedures.
摘要:
This invention relates to molded polyurethane foams prepared by reacting a specific polyisocyanate with a specific polyol in the presence of water as a blowing agent and a catalyst, wherein (a) the polyisocyanate comprises a mixture of (i) a specified amount of polymethylene polyphenyl polyisocyanate and (ii) an NCO-terminated prepolymer prepared from the reaction of an organic polyisocyanate with a specified amount of poly(oxytetramethylene)glycol, or a specific NCO-terminated prepolymer prepared from the reaction of (i) an organic polyisocyanate, (ii) a specified amount of polymethylene polyphenyl polyisocyanate and (iii) a specified amount of poly(oxytetramethylene)glycol, (b) the polyol contains a specified amont of polymer polyol prepared from the reaction of a polyetherpolyol with an ethylenic unsaturated monomer, and (c) the catalyst contains an organotin compound. The molded polyurethane foams can be prepared under good demoldability and have excellent abrasion resistance, and therefore, can be useful for automotive steering wheels, headrests, armrests and the like.
摘要:
This invention relates to polyurethane foam moldings prepared by reacting a specific polyisocyanate with a polyol in the presence of water as the primary blowing agent, wherein the polyisocyanate comprises a specific polyisocyanate mixture of a NCO-terminated prepolymer prepared employing poly(oxytetramethylene)glycol ("PTMG") with polymethylene polyphenyl polyisocyanate ("Polymeric MDI"), or a specific NCO-terminated prepolymer prepared from the reaction of an organic polyisocyanate containing Polymeric MDI as an essential component with PTMG. The polyurethane foam moldings have excellent abrasion resistance and can be useful for automotive steering wheels, headrests, armrests and the like.