Abstract: A method for treating a plastic, such as polyethylene or polypropylene, to remove at least a portion of at least one contaminant includes combining the plastic with a supercritical medium, such as carbon dioxide or sulfur hexafluoride, whereby at least a portion of the contaminant dissolves in the supercritical medium. Alternatively, the plastic can be combined with a suitable liquid medium, such as carbon dioxide or liquid sulfur hexafluoride. At least a portion of the medium, containing the dissolved contaminant, is separated from the plastic, thereby removing at least a portion of the contaminant from the plastic.

Abstract: A method of improving the oxidative thermal stability of ethylene polymers is disclosed. The method comprises removing residual unreacted monomer(s), solvent and thermally unstable species from the molten polymer. The resulting polymer is characterized by having an oxidative exotherm of not more than about 50 percent of the original polymer, as measured by differential scanning calorimetry.

Abstract: A mold and divider assembly for creating a solid surface countertop having an exterior edge according to different shapes and sizes. The mold includes a planar shaped surface which is bounded by a polygonal shaped body, at least one side of which has a raised and inwardly contoured mold defining edge. A first elongated dividing member equals a length of a first selected side of the mold and is placeable upon the planar surface so as to be movable in directions towards and away from the first selected side. A second elongated dividing member extends between the first dividing member and a second selected side of the mold so that the dividing members define in combination a subset area of the mold for receiving a resinous material pour. The second dividing member may be providing in differing lengths as a kit for producing an assortment of countertops according to differing dimensions. The mold may further be provided in a generally L-shape or rectangular shape.

Abstract: In a process for the continuous preparation of polymers from reaction components, in particular of copolymers of styrene and acrylonitrile, by mass or solution polymerization, the reaction components are passed through a circulation reactor which has at least one tube reactor in which is arranged at least one static mixing element through which a liquid heat-transfer medium flows. The static mixing element has multiply curved pipelines.

Abstract: This invention relates to a process for transitioning between incompatible polymerization catalyst systems. Particularly, the invention relates to a process for transitioning from an olefin polymerization reaction utilizing a traditional Ziegler-Natta catalyst system to a metallocene-olefin polymerization reaction.

Abstract: A mold core assembly for removable installation in a molding machine includes a first lock element attached to a core and a second lock element movably attached to a core retainer. The second lock element is movable between a locked position fitted in locking connection with the first lock element and an unlocked position separated from the first lock element. A slip ring surrounds the first lock element of the core, engaging and holding the second lock element in its locked position. A spring is connected between the core retainer and the slip ring, with the spring biased to oppose movement of the slip ring away from its locked position so that the core is normally held in its locked position in the core retainer.

Abstract: Apparatus for the manufacturing of prestressed reinforced concrete railroad ties and the like in which the apparatus consists of an elongated spine or compression member which has no foundation but rather is independent of the supporting surface upon which it rests. In one version of the apparatus two bridge members confront the opposite ends of the spine and permanent tension resisting members pass beneath the spine from end to end of the spine and are attached to the lower ends of the bridge members. In another version two structural members are embedded in the concrete of the spine and protrude to provide terminal members.

Abstract: The present invention is an improved method for making fiber polymer optical fiber cable and graded index optical fibers. The polymer can be any shape including, but not limited to sheets, films or cable. The present invention also includes improved polymer optical fibers that incorporate compositions that shift the wavelength of radiation from ultraviolet radiation or X-ray radiation or infrared radiation to visible radiation.

Abstract: This invention relates to a process for transitioning between incompatible polymerization catalyst systems. Particularly, the invention relates to a process for transitioning from an olefin polymerization reaction utilizing a traditional Ziegler-Natta catalyst system to a metallocene-olefin polymerization reaction.

Abstract: A mold box for molding concrete products includes a pair of opposed substantially parallel end plates. A pair of opposed substantially parallel mounting brackets are positioned at opposite ends of the end plates and together with the end plates form a substantially rectangular mold box. A corner portion is defined adjacent the juncture of each mounting bracket with each end plate. At least one partition plate extends from one end plate to the other between the mounting brackets. An alignment pin is formed on the mounting bracket at each corner portion and an alignment bore coaxial with the pin is formed on the end plate. The bores are sized and positioned so that when each bore has its associated alignment pin therein the mold box assembly is sufficiently aligned to form molded products.

Abstract: The subject invention pertains to large particle size, attrition-resistant, continuous, but wrinkled, high surface area aqueous fluid absorbent polymers, preferably of a crosslinked acrylic acid or acrylate. These absorbents have absorption rates superior to spherical absorbents. The subject invention further pertains to a process of preparing such polymers comprising suspension polymerization with an at least partially off phase soluble initiator. The subject invention further pertains to absorbent structures containing such polymers and to the use of such polymers therein.

Abstract: A hgh-visbility inflated game ball such as a basketball, football, soccer ball, volleyball or the like. The game ball includes a central inflated portion and a metallocene catalyzed polyolefin cover formed over the central inflated portion. In one embodiment, the cover has fluorescent pigment, fluorescent dye, and/or optical brighteners incorporated therein in order to impart to the cover a reflectance of at least 75% in at least a part of the visible spectrum. In another embodiment, reflective metallic particles are incorporated in addition to, or in place of the pigment, dye and optical brightener in order to add a glittery appearance to the ball cover. The particularly preferred game ball of the invention is a basketball. The game ball is particularly useful at dusk when conventional basketballs of a dull orange color become difficult to see.

Abstract: A method for producing a poly(vinyl chloride) comprises polymerizing vinyl chloride or a mixture of copolymerizable monomers containing vinyl chloride as the main component, in an aqueous medium, wherein the polymerization is carried out in a reaction vessel which is formed by arranging partition plates at certain intervals at right angles to the outer surface of an inner barrel and overlaying outer strips on and between the free ends of the partition plates to thereby form a flow passage unit having a flow passage for a heating medium defined by the partition plates, the inner barrel and the outer strips ("a temperature control element"); fixing the temperature control element in a vessel body so as to oppose the side of the outer strips with a gap to the inner surface of the vessel body, and sealing the upper and lower portions of the gap formed between the outer strip side of the temperature control element and the inner surface of the vessel body to form a gap chamber.

Abstract: A method of manufacturing a polyolefin solution continuously and in a stable manner with a high yield which comprises heading a polyolefin resin with a liquid composed of a solvent for the polyolefin resin, and is characterized in that; (1) a continuous kneader having a self-cleaning action is used, and (2) a starving state is maintained in the internal sections of the header at a polyolefin resin feed section, a liquid feed section, and the section in which the kneading of the polyolefin resin and the liquid is initially carried out.

Abstract: The present invention relates to a process for modifying a polyethylene in an extruder by bringing the polyethylene into contact with oxygen or a gas mixture containing oxygen in the extruder, optionally in the presence of a relatively small quantity or preferably in the absence of short-term antioxidant agent. The polyethylene is then treated thermomechanically in the molten state in the extruder supplying a relatively high specific mechanical energy, the thermomechanical treatment is completed when the value of the loss tangent of the polyethylene characterizing its viscoelastic state decreases in a desired proportion. The polymer thus treated is particularly suitable for being transformed by blown extrusion into a film having a considerably increased bubble stability.

Abstract: An olefin polymerization process in which at least two introductions of hydrogen are made during the olefin polymerization reaction. Suitable catalysts include metallocenes of the general formula (Cp).sub.m TiX.sub.n, wherein Cp is a substituted or unsubstituted cyclopentadienyl ring, X is a halogen, m=1-2, n=2-3, and wherein m+n=4, and conventional Ziegler-Natta catalysts blended with or modified by such metallocenes.

Abstract: In a process and an apparatus for the continuous preparation of polymers from reaction components, in particular of copolymers of styrene and acrylonitrile, by bulk or solution polymerization, the reaction components are passed through a recycle reactor which has at least one tube bundle reactor whose tubes are in thermal contact with a liquid heat-transfer medium and which is connected to at least one static mixing element.

Abstract: A cassette mold holder (7) has a cassette mold insertion portion (12) into which a cassette mold (14) is inserted from above. The insertion portion (12) is inclined with respect to a vertical line (VL) by about 6.degree. when the holder (7) is attached to an injection molding machine. An insertion port (121) of the insertion portion (12) is large, and the inside surfaces (12b, 12c) adjacent to the insertion port have tapered surfaces (12d, 12e) respectively to guide the cassette mold into the insertion hollow portion. Since the insertion portion (12) is inclined, when the cassette mold (14) is inserted, one of the inside surfaces (12b) and the bottom (122) function as reference surfaces to position the cassette mold automatically. Further, the cassette mold (14) can be inserted easily along the tapered surfaces (12d, 12e).

Abstract: A process for the preparation of copolymers of ethylene and dicarboxylic acid in the presence of a free-radical inhibitor. The process comprises of warming a mixture of ethylene and C.sub.3 -C.sub.6 -alkenecarboxylic acid to a temperature of from 60.degree. to 100.degree. C. before addition of the free-radical inhibitor. The maximum polymerization temperature to recover said copolymers of ethylene is in the range of from 100.degree. to 260.degree. C.; and wherein said copolymer comprises from 94 to 99.5 mol % of ethylene and from 0.5 to 6.0 mol % of C.sub.3 -C.sub.6 -alkenecarboxylic acid.

Abstract: Process for the gas-phase polymerization of ethylene and ethylene mixtures with .alpha.-olefins CH.sub.2 .dbd.CHR in the presence of a high activity catalyst comprising a titanium compound containing at least one Ti-halogen bond, supported on magnesium dichloride in active form said process comprising the steps of: (a) contacting the catalyst component; (b) prepolymerizing ethylene or ethylene mixtures with .alpha.-olefins in order to produce a polymer amount of from approximately 5 g per g of solid component, up to an amount corresponding to about 10% of the final catalyst yield; (c) polymerizing ethylene or ethylene mixtures with .alpha.-olefins in the gas-phase, in the presence of the prepolymer-catalyst system obtained in (b), while maintaining in the gas phase a molar concentration concentration of the alkane comprised between 20 and 90% with respect to the total gases.