Reaction injection molding of ceramic or metallic greenbodies
AssigneeHoechst Celanese Corporation
InventorsO. Richard Hughes, John R. Costanza
Life of this patent
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Abstract
Greenbodies are produced by a RIM injection molding process wherein a homogeneous mixture of finely divided ceramic or metallic material and a polymerizable monomeric binder is injected into a mold and held at an elevated temperature for a sufficient time to polymerize the binder and form the greenbody. A preferred monomeric binder includes di- and tri-acrylate or -methacrylate esters of polyols. The low viscosity of the monomeric binder allows a loading of ceramic material of greater than 50 vol. % without adversely affecting the ability to injection mold the mixture.
Claims60
A RIM process for producing ceramic or metallic greenbodies comprising the steps of:
- forming a homogeneous RIM mix by dispersing finely divided ceramic or metallic material in a polymerizable monomeric binder comprising multifunctional acrylate or methacrylate esters, injecting said mix into a mold held at a temperature sufficient to polymerize said monomeric binder, maintaining said mix in said mold at said polymerization temperature for a time sufficient to polymerize and harden said binder to produce a molded product, and removing said molded product from said mold.
A ceramic RIM process for producing a sintered ceramic article comprising the steps of:
- forming a homogeneous mixture containing finely divided ceramic material and a polymerizable monomeric binder comprising multifunctional acrylates selected from the polyol esters of polyacrylate or polymethacrylate, injecting said homogeneous mixture into a mold, maintaining said mixture in said mold at a temperature and for a sufficient time to polymerize said monomeric binder and cause the hardening thereof to produce a molded product, removing said binder and subsequently sintering said product at a temperature of from 1,000.degree. and 2,200.degree. C. to produce a sintered product.
The process of clam 30 wherein said ester is derived from methacrylic acid.
A RIM process for producing ceramic or metallic greenbodies comprising the steps of:
- forming a homogeneous RIM mix by dispersing finely divided ceramic or metallic material in a polymerizable monomeric binder, injecting said mix into a mold held at a temperature sufficient to polymerize said monomeric binder, maintaining said mix in said mold at said polymerization temperature for a time sufficient to polymerize and harden said binder to produce a molded product, and removing said molded product from said mold.
Dependencies are inferred from the claim text.