Abstract: Improved flame retardant compositions suitable for insulating wire and cable products comprised of ethylene-alkoxy silane copolymer, halogenated organic compound, antimony trioxide, silane condensation catalyst and magnesium hydroxide are provided. Additionally, antioxidant(s), other mineral fillers and other conventional compounding ingredients may be included in the formulations. The compositions have good processability and are capable of being cured under ambient conditions to provide products which meet all of the specifications of SAE J-1128 for thin wall crosslinked polyolefin low tension primary cable insulation. Wire and cable products comprising a metal conductor coated with from 2 to 100 mils of the flame retardant insulation are also disclosed.
Abstract: Improved carbon black concentrates and extrusion compositions produced therefrom are provided. The extrusion compositions are resistant to thermo-oxidative degradation and have significantly improved carbon black dispersion rendering them useful for wire and cable and other applications. The concentrates are mixtures of a mercaptobenzimidazole compound, carbon black and polyolefin resin.
Abstract: An adjustable shoe for ice skates, consisting of a front portion and a rear portion which are connected by a track that permits the front and rear portions to be moved relative to one another. A cavity in the front and rear shoe portions to receive the blade of an ice skate with the chassis of the skate riding on the top ridge that surrounds the cavity. Adjustable strap or straps are provided to secure the shoe to an ice skate.
Abstract: Improved compositions useful for the production of rotomolded articles having a foamed interior and non-foamed exterior skin are provided. The compositions of the invention are comprised of a first thermoplastic resin component which is an ethylene polymer in pellet form containing a chemical foaming agent, an organic peroxide and, optionally, a metal-containing activator compound and a second resin component which is a powder and can be a thermoplastic ethylene polymer or ethylene copolymer having less than 30% crystallinity. An improved one-step process for producing foamed rotomolded articles having foamed interiors and non-foamed exterior skins is also provided.
Abstract: Improved compositions useful for the production of rotomolded articles having a foamed interior and non-foamed exterior skin are provided. The compositions of the invention are comprised of a first thermoplastic resin component which is an ethylene polymer in pellet form containing a chemical foaming agent, an organic peroxide and, optionally, a metal-containing activator compound and a second resin component which is a powder and can be a thermoplastic ethylene polymer or ethylene copolymer having less than 30% crystallinity. An improved one-step process for producing foamed rotomolded articles having foamed interiors and non-foamed exterior skins is also provided.
Abstract: Improved compositions useful for the production of foamed rotomolded articles are provided. The compositions of the invention are comprised of a first thermoplastic resin component which is an ethylene polymer in pellet form containing a foaming agent and a second thermoplastic resin component which is a powder consisting of a mixture of different particle size and melt index ethylene polymers. An improved process for producing foamed rotomolded articles having uniformly foamed interiors and smooth exterior skins which are substantially free of surface defects is also provided.
Abstract: Improved compositions useful for the production of foamed rotomolded articles are provided. The compositions of the invention are comprised of a first thermoplastic resin component which is an ethylene polymer in pellet form containing a foaming agent and a second thermoplastic resin component which is a powder consisting of a mixture of different particle size and melt index ethylene polymers. An improved process for producing foamed rotomolded articles having uniformly foamed interiors and smooth exterior skins which are substantially free of surface defects is also provided.
Abstract: Semiconductive polyolefin formulations are provided which are readily extrudable into films and coatings having low surface resistivity. The formulations of the invention are comprised of a polyethylene resin with 6 to 15 weight percent of a mixture of two different conductive carbon blacks. The conductive blacks have different structures as defined by their BET surface areas and dibutyl phthalate adsorption numbers. The extrudable semiconductive compositions of the invention have complex viscosities of 3000 to 10000 poise and dispersion numbers from 50 to 600. Extruded films having surface resistivities of less than 10 log ohms produced from the above-identified polyolefin compositions are also provided.
Abstract: An improved gas-phase polymerization process for producing in-situ thermoplastic polyolefins in multiple reactors using high activity Ti/Al catalysts is provided. The improvement consists of developing a control parameter derived from eight integrated regions of the copolymer .sup.13 C NMR spectrum, defining the limits of the control parameter for the process, and operating the process to maintain the parameter within the defined limits. This is accomplished by adjusting the amount of ethylene fed to the secondary reactor and adjusting other process variables as required. Thermoplastic polyolefins, i.e., modified polypropylenes, having reduced hexane extractables and improved paint adhesion are also disclosed.
Abstract: Terpolymers of ethylene, vinyl acetate and isobutylene as flow improvers in distillate fuels. The terpolymers have number average molecular weights in the range of about 1,600 to about 3,000, and weight average molecular weights in the range of about 4,000 to about 18,000. These terpolymers provide improved low temperature flow characteristics in middle distillate fuels.
Abstract: A catalyst component useful in the polymerization of olefins which includes a support formed of a copolymer of an olefin and a silane monomer having at least one unsaturated hydrocaryl substitutent. A process for making the catalyst component as well as a catalyst composition which includes the catalyst component is also set forth.
Abstract: The instant invention is directed to a process for preparing peroxide modified polypropylene/polyethylene blends that have superior extrusion coating properties. More specifically, the peroxide modified PP/PE blends produced by the instant invention exhibit a pronounced viscosity upturn at low frequencies (about <1.0 rad/sec) in the dynamic rheological data. Specifically, the blends show an increase in their dynamic complex viscosity, .eta.*, and dynamic storage modulus, G' values at frequencies of less than about 1.0 rad/sec. The present invention also relates to peroxide modified PP/PE blends that are produced from the process of the instant invention. Such polymeric blends that are produced from the inventive method exhibit superior dynamic theological properties, especially melt strength, compared with prior art blends. Moreover, the peroxide modified PP/PE blends of the present invention show markedly reduced draw resonance behavior.
Type:
Grant
Filed:
March 11, 1994
Date of Patent:
June 17, 1997
Assignee:
Quantum Chemical Corporation
Inventors:
Chun D. Lee, Ramesh N. Shroff, Manivakkam J. Shankernarayanan
Abstract: Adhesive blends having special utility in the formation of composite structures with LDPE, EVOH, and impact-modified polystyrene comprise a mixture of an ethylene/ester copolymer such as EVA, polystyrene, such as impact-modified polystyrene, and a functionalized SEBS block copolymer.
Abstract: An improved gas-phase copolymerization process for producing copolymers of propylene and ethylene in multiple reactors using high activity Ti/Al catalysts is provided. The improvement consists of developing a control parameter derived from eight integral regions of the copolymer .sup.13 C NMR spectrum, defining the limits of the control parameter for the process, and operating the process to maintain the parameter within the defined limits. This is accomplished by adjusting the amount of ethylene in the primary and/or secondary reactor and adjusting other process variables as required.
Abstract: The present invention is directed to a supported metallocene catalyst useful in the polymerization of .alpha.-olefins which is obtained by tethering a metallocene catalyst component to the surface of a particulate, functionalized copolymeric support material.
Abstract: Useful stabilizer combinations and propylene polymer compositions stabilized therewith having improved resistance to discoloration upon processing are provided. The stabilizer combinations of the invention are comprised of a mixture of calcium salts of stearic acid and lactic acid and a tocopherol-containing mixture consisting essentially of .alpha.-tocopherol, glycerin, polyethylene glycol having an average molecular weight of about 300 and glycerol monocaprylate. Propylene homopolymers and random, block and impact copolymers of propylene are stabilized in accordance with the invention.
Abstract: Anhydride-functionalized polymers are modified in accordance with the present invention by reacting all or a portion of the anhydride functionality with an aliphatic alcohol to convert the anhydride groups to half-esters. Half-esters produced by modifying maleic anhydride grafted ethylene polymers with alcohols are particularly useful. Adhesive blends obtained by combining the alcohol-modified polymers with one or more polyolefin base resins and composite structures wherein said adhesive blends are adhered to EVOH are also provided. Modification of the maleic anhydride grafts in accordance with the process of this invention makes it possible to produce films having improved optical quality.
Abstract: A die for a blow molding machine has at least one circumferential rectangular cutout section contiguous with the die exit in at least the die ring or the mandrel. The rectangular cutout section expands the material flow channel between the die ring and the mandrel to increase the volume flow of material passing through the die exit at the rectangular cutout section. However, the constant length of the rectangular cutout section in a longitudinal direction maintains a constant linear velocity of material flowing through the die exit.
Abstract: A process is provided to improve the properties of polyethylene resins obtained from chromium catalyzed polymerizations and blow molded bottles produced therefrom. The process entails modifying the polyethylene resin by contacting the resin in a molten state with an organic peroxide at a temperature above the decomposition temperature of peroxide. Polyethylene resins utilized for the process have specific densities, melt indexes, long chain branching indexes, unsaturation contents and molecular weight distributions. Blow molded bottles produced from the modified resins have significantly increased top load stress crack resistance and improved swell characteristics.
Abstract: Phillips' process high density polyethylene resin compositions having improved processing stability are obtained using a combination of stabilizers comprised of a hindered phenol and a phosphite compound having three cyclic phosphite moieties linked via a nitrogen atom. More specifically, the phosphite compound is 2, [[2,4,8,10-tetrakis(1,1-dimethylethyl)dibenzo[d,f][1,3,2]-dioxaphosphepin- 6-yl]oxy]-N,N-bis [2-[[2,4,8,10-tetrakis (1,1-dimethylethyl) dibenzo[d,f][1,3,2]dioxaphosphenpin-6-yl]oxy]-ethyl]ethanamine. With the HDPE compositions stabilized in accordance with the invention, it is possible to eliminate undesirable rapid changes in melt viscosity which can occur when Phillips' process HDPE resins are processed under conditions of high shear.