227 results about "Reaction injection molding" patented technology

Main chain thermotropic liquid crystal esters, ester-imides, and ester-amides were prepared from AA, BB, and AB type monomeric materials and were end-capped with phenylacetylene, phenylmaleimide, or nadimide reactive end-groups. The resulting reactive end-capped liquid crystal oligomers exhibit a variety of improved and preferred physical properties. The end-capped liquid crystal oligomers are thermotropic and have, preferably, molecular weights in the range of approximately 1000-15,000 grams per mole. The end-capped liquid crystal oligomers have broad liquid crystalline melting ranges and exhibit high melt stability and very low melt viscosities at accessible temperatures. The end-capped liquid crystal oligomers are stable for up to an hour in the melt phase. These properties make the end-capped liquid crystal oligomers highly processable by a variety of melt process shape forming and blending techniques including film extrusion, fiber spinning, reactive injection molding (RIM), resin transfer molding (RTM), resin film injection (RFI), powder molding, pultrusion, injection molding, blow molding, plasma spraying and thermo-forming. Once processed and shaped, the end-capped liquid crystal oligomers were heated to further polymerize and form liquid crystalline thermosets (LCT). The fully cured products are rubbers above their glass transition temperatures. The resulting thermosets display many properties that are superior to their non-end-capped high molecular weight analogs.

An article or polishing pad for altering a surface of a work piece includes a polymer matrix created by reaction injection molding of size controlled gas bubbles within a polyurethane matrix. The proposed liquid urethane precursor is first injected into an actuated mold and cured. The molded product is then removed from the mold and double side faced or ground to form a single thin polishing pad comprising a single layer of homogeneous material.

A high quality polishing pad suitable for chemical mechanical polishing (CMP) of semiconductor wafer, etc. which is not affected by the change of polishing conditions during polishing and can attain excellent removal rate, capacity of step height reduction and uniformity is described, wherein a polyurethane-based foam 12 having fine and uniform cells 20 suitable for polishing of semiconductor material, etc. obtained by reaction-injection molding a gas-dissolved raw material prepared by dissolving an inert gas in a mixture of a polyurethane or polyurea as a main raw material and various subsidiary raw materials under pressure is used.

A method of manufacturing an extruded part having an exterior shell and a core foam material. The method includes extruding the exterior shell from an extrusion die, and reaction injection molding the core foam material within an interior of the exterior shell using a distribution block having a plurality of orifices configured to inject the core foam material within the interior of the exterior shell. The orifices are configured to evenly distribute the core foam material throughout the interior of the exterior shell. the method can be used to form an exterior shell having a plurality of internal chambers, where the orifices of the distribution block are configured to inject core foam material within the plurality of internal chambers.

The present invention provides an apparatus for forming a chemical mechanical polishing pad, comprising a tank with polymeric materials, a storage silo with microspheres, a isocyanate storage tank with isocyanates and a premix prep tank for forming a pre-mixture of the polymeric materials and the microspheres. The invention further provides a premix run tank for storing the pre-mixture, a mixer for forming a mixture of the pre-mixture and the isocyanates, a closed mold for reaction-injection molding the mixture and a vacuum for degassing at least one of the tank, isocyanate storage tank or the mold.

A single-layered polishing pad suitable for chemical mechanical polishing (CMP) of semiconductor wafers, etc., which attains excellent step height reduction and in-plane uniformity and is integrally molded by reaction injection molding, is provided. The polishing pad is a polyurethane-based foam 12 having a desired shape, as obtained by molding a gas-dissolved raw material having an inert gas dissolved under pressure in a polyurethane-base resin raw material by a reaction injection molding method, and includes a polishing region 14 having a polishing surface 14a suitable for polishing semi-conductor materials, etc. and having a Shore D hardness in the range of from 40 to 80 and a stress reduction region 16 which is present in the side opposing to the polishing surface 14a and which, when provided with a stress adjusting portion 22 of a desired pattern, is set up so as to have an amount of deflection, as applied with a load of 0.05 MPa, of 10 μm or more.