摘要:
This invention relates to a reaction injection molding process for preparing a molded product by reaction of a mixture of(a) an organic polyisocyanate;(b) one or more compounds containing at least two isocyanate-reactive groups;(c) about 2 to about 20% by weight, based on the weight of the molded product, of rigid fibers having a diameter of from about 5 to about 10 micrometers and a length ranging from the diameter of the fiber up to about 2 millimeters, preferably in admixture with component (b);and, optionally,(d) an inert gas dissolved in at least one of components (a) or (b) in an amount sufficient to produce a molded product having a density of at least 0.80 g/cm.sup.3 ; and(e) up to 15% by weight, based upon the weight of the molded product, of a filler other than rigid fibers (c).
摘要翻译:本发明涉及通过(a)有机多异氰酸酯的混合物反应制备模塑产品的反应注射成型方法; (b)一种或多种含有至少两个异氰酸酯反应性基团的化合物; (c)约2至约20重量%,基于成型产品的重量,直径为约5至约10微米的刚性纤维和从纤维直径至约2毫米的长度 ,优选与组分(b)混合; 和任选地,(d)溶解在组分(a)或(b)中的至少一种中的惰性气体,其量足以产生密度至少为0.80g / cm 3的模制产品; 和(e)基于成型产品的重量,高达15重量%的除刚性纤维(c)之外的填料。
摘要:
This invention relates to a reaction injection molding process for preparing a molded product by reaction of a mixture of(a) an organic polyisocyanate;(b) one or more compounds containing at least two isocyanate-reactive groups;(c) about 2 to about 20% by weight, based on the weight of the molded product, of rigid fibers having a diameter of from about 5 to about 10 micrometers and a length ranging from the diameter of the fiber up to about 2 millimeters, preferably in admixture with component (b);and, optionally,(d) an inert gas dissolved in at least one of components (a) or (b) in an amount sufficient to produce a molded product having a density of at least 0.80 g/cm.sup.3 ; and(e) up to 15% by weight, based upon the weight of the molded product, of a filler other than rigid fibers (c).
摘要翻译:本发明涉及通过(a)有机多异氰酸酯的混合物反应制备模塑产品的反应注射成型方法; (b)一种或多种含有至少两个异氰酸酯反应性基团的化合物; (c)约2至约20重量%,基于成型产品的重量,直径为约5至约10微米的刚性纤维和从纤维直径至约2毫米的长度 ,优选与组分(b)混合; 和任选地,(d)溶解在组分(a)或(b)中的至少一种中的惰性气体,其量足以产生密度至少为0.80g / cm 3的模制产品; 和(e)基于成型产品的重量,高达15重量%的除刚性纤维(c)之外的填料。
摘要:
The mold broadly consists of an upper and lower mold part. The parts define a mold cavity when the mold is in the closed position. A channel is provided in one of the parts, with the channel completely surrounding the cavity. One upper edge of the channel forms at least a portion of the outer edge of the mold cavity. The channel is at least partially filled with an elastomeric material. A shear plate is attached to the other part in a location opposite the channel. When the mold is in the closed position, the shear plate enters the channel, presses against the elastomeric material and presses against the outer edge of the mold cavity. The shear plate is also provided with one or more tapered slots which allow gases to escape from the mold cavity when the mold is in the closed position.
摘要:
A novel polyisocyanate which is liquid and room temperature stable and has an isocyanate group content of from 10 to 30% by weight is prepared by reacting:a) an isocyanate mixture of 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, and an amount of an isocyanate based upon diphenylmethane diisocyanate having an isocyanate functionality of more than 2, such that the total isocyanate mixture a) has an average isocyanate functionality of from 2.02 to 2.50, andb) one or more polyols selected from the group consisting of1) diols having molecular weights of from 1000 to 5000,2) triols having molecular weights of from 1000 to 6000, and3) mixtures thereof.When used in a RIM process, parts are produced which have excellent low temperature impact properties.
摘要:
A RIM process utilizing a reaction product of an MDI containing from 6 to 50% by weight of the 2,4'-isomer and a polypropylene glycol as the isocyanate reactant results in a molded product having excellent low temperature impact properties.
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:
It has been found that the use of specific expanded organic microspheres greatly improve the RIM process by (i) significantly enhancing the blowing action of air and/or nitrogen, (ii) providing for uniform density of the molded part, (iii) allowing for the reduction of internal mold pressures, (iv) substantially eliminating surface defects, (v) allowing for a significant reduction in density in the molded product, (vi) allowing for a substantial increase in the amount of air and/or nitrogen that can be dissolved in the isocyanate-reactive component, and (vii) significantly reducing shrinkage in the molded part.
摘要:
The present invention is directed to a process for producing a molded product comprising(A) reacting:(i) an organic polyisocyanate having an isocyanate group content of from 5 to 45% by weight, preferably from 15 to 35% by weight, and most preferably from 20 to 35% by weight, prepared by reacting:(a) an organic di- and/or polyisocyanate, and(b) an active hydrogen containing fatty acid ester prepared by reacting an alcohol or polyol with an aliphatic, saturated or unsaturated fatty acid, said ester being characterized in that at least one aliphatic acid which contains more than 8 carbon atoms is built into the molecule, said ester further characterized as having an acid number of from 0 to 100 and a hydroxyl number of from 0 to 150 with at least one of said numbers being greater than zero, said ester having an average molecular weight of from 500 to 5000,(ii) an isocyanate reactive component comprising:(a) from about 0.5 to about 10% by weight based on the weight of components (ii)(b) and (ii)(c), of a zinc carboxylate containing from 8 to 24 carbon atoms per carboxylate group,(b) from about 0.3 to 100% by weight, preferably from 0.5 to 95% by weight, more preferably from 5 to 45% by weight, and most preferably from 10 to 35% by weight, based on the weight of components (ii)(b) and (ii)(c), of a compatibilizer which compatibilizes said carboxylate in component (ii), and(c) 0 to about 99.5% by weight, preferably from 5 to 99.5% by weight, more preferably from 55 to 95% by weight, and most preferably from 65 to 90% by weight, based on the weight of components (ii)(b), and (ii)(c), of at least one active hydrogen containing compound other than said compatibilizer,at an isocyanate index of from about 90 to about 400 and preferably from about 95 to about 115, in a closed mold,(B) allowing the components to react, and(C) removing the product from the mold.
摘要:
This invention relates to high performance RIM (reaction injection molded) poly(urethane)urea elastomers, and to a process for their production. These elastomers comprise the reaction product of an allophanate-modified diphenylmethane diisocyanate prepolymer having an NCO group content of about 5 to about 30%, with an isocyanate-reactive component comprising a high molecular weight amine-terminated polyether polyol, an aromatic diamine chain extender, and, optionally, a chain extender or crosslinker selected from the group consisting of aliphatic amine terminated polyether polyols and aliphatic hydroxyl terminated polyether polyols, optionally, in the presence of an internal mold release agent, a surfactant and a filler.