摘要:
An improved light stable polyether/polyol based aliphatic urethane thermoplastic elastomer prepared from reacting inter alia a polyol having low terminal end unsaturation and an organic diisocyanate. The elastomer is characterized by ultra violet stabilizer being present in a range of 0.25% to 2.0% at a total concentration of 1.0% to 2.0%, an antioxidant being present at a total concentration of 0.10% to 1.0%, and colorants/pigment being present in a total concentration in a range from 1.0% to 2.05% to produce an elastomer capable of withstanding Xenon arc artificial weathering with DE≦3.00 after 2450 kilojoules of exposure.
摘要:
An improved light stable polyether/polyol based aliphatic urethane thermoplastic elastomer prepared from reacting inter alia a polyol having low terminal end unsaturation and an organic diisocyanate. The elastomer is characterized by ultraviolet stabilizer being present in a range of 0.25% to 2.0% at a total concentration of 1.0% to 2.0%, an antioxidant being present at a total concentration of 0.10% to 1.0%, and colorants/pigment being present in a total concentration in a range from 1.0% to 2.05% to produce an elastomer capable of withstanding Xenon arc artificial weathering with DE.ltoreq.3.00 after 2450 kilojoules of exposure.
摘要:
Compositions for forming molded articles, particularly, shells for automotive applications are made up of melt blends of aliphatic thermoplastic urethane elastomer and an olefin-containing block copolymer crosslinked to a gel content of from 5 to 95%. These compositions may be blended to form a powder, pellets, microspheres or minibeads which may then be cast to form air bag door and instrument panel cover skins which may meet automotive deployment and weathering requirements.
摘要:
Method and apparatus including a powder box and heatable shell tool are disclosed for forming a thermoplastic automotive air bag cover skin with a lesser strength thermoplastic tear seam strip insert wherein the latter is initially formed with a protruding rib on one side and a pointed ridge on an opposite side. A heat resistant elastomeric transfer socket attached to the powder box interior receives and holds the insert rib and thereby the insert in a prescribed tear seam configuration and then positions the tear seam strip insert against a heated skin defining mold surface on the shell tool when the powder box is joined with the latter. The skin is formed by casting thermoplastic powder from the powder box against the heated mold surface and about the tear seam insert. The pointed ridge of the tear seam strip insert is pressed with a limited force against the heated mold surface by the transfer socket and prevents air entrapment between the tear seam strip insert and mold surface as the insert melts and joins with a surrounding layer of powder melt that forms the skin on cooling. In the process of melting, the pointed edge of the ridge and all of the rib of the insert melts and becomes part of a tear seam where the insert fuses with the skin while conforming to the mold surface to smoothly blend with the outer side of the skin while the backside of the insert smoothly blends with the surrounding inner side of the skin.
摘要:
A filled aliphatic thermoplastic urethane automotive air bag door tear seam insert is formed of a polyol, a chain extender, an organic diisocyanate, an antioxidant, a urethane catalyst, and a weakening filler wherein the filler is present in a range of approximately 60% to 80% by weight and is selected from the group consisting of anhydrous calcium sulfate, nepheline syenite and hollow silica-alumina alloy microspheres and combinations thereof. The filler may be only one of the group members or any combination thereof and in either equal or unequal proportions. The insert is adapted to be molded in place in a cover skin cast there about. The cast cover skin including the tear seam insert may be coated with a light stable paint; or for light stability and color matching, the urethane elastomer forming the cover skin and insert is formulated to include an ultra violet stabilizing agent(s) and a color pigment(s) in certain critical concentrations to obtain the desired effect.
摘要:
Compositions for forming molded articles, particularly, shells for automotive applications are made up of melt blends of an aliphatic thermoplastic urethane elastomer and one or more polyolefin-based modifiers. These compositions may be blended to form a powder, pellets, microspheres or minibeads which may then be cast to form air bag door and instrument panel cover skins which may meet automotive deployment and weathering requirements.
摘要:
Compositions for forming molded articles, particularly, shells for automotive applications are made up of melt blends of aliphatic thermoplastic urethane elastomer and an olefin-containing block copolymer crosslinked to a gel content of from 5 to 95%. These compositions may be blended to form a powder, pellets, microspheres or minibeads which may then be cast to form air bag door and instrument panel cover skins which may meet automotive deployment and weathering requirements.
摘要:
Compositions for forming molded articles, particularly, shells for automotive applications are made up of an aliphatic thermoplastic urethane/urea elastomer and, optionally, one or more copolymers, such as an olefin-containing or styrene containing copolymer. These compositions may be used to form a powder, pellets, microspheres or minibeads which may then be cast to form air bag door and instrument panel cover skins which may meet automotive deployment and weathering requirements.
摘要:
Compositions for forming molded articles, particularly, shells for automotive applications are made up of melt blends of an aliphatic thermoplastic urethane elastomer and one or more polyolefin-based modifiers. These compositions may be blended to form a powder, pellets, microspheres or minibeads which may then be cast to form air bag door and instrument panel cover skins which may meet automotive deployment and weathering requirements.
摘要:
A solvent flush reaction injection molding mixhead has a mixing chamber with a solvent inlet port in one end and a chemical outlet port in an opposite end. A pair of hydraulically operated chemical injectors are connected to the mixing chamber between the solvent inlet port and chemical outlet port to inject liquid reaction molding chemicals at high pressure through injector ports into the mixing chamber. The mixed chemicals are delivered through the chemical outlet port to a spray wand on the mixhead for application to a mold surface or an object requiring a foam coating. A flush valve is associated with the solvent inlet port and is moveable from a closed position to block the solvent inlet port while the chemicals are injected into the mixing chamber, and an open position where liquid solvent under a high pressure is supplied through turbulator ports into the mixing chamber to clean and flush any remaining mixed chemicals from the flush valve, the mixing chamber including the chemical injector ports, and the spray wand.