Abstract: A process for preparing a propylene polymer composition comprising conducting multistage polymerization including a step (a) for preparing a propylene (co)polymer (a) and a step (b) for preparing an ethylene copolymer (b) in the presence of (A) a transition metal compound and (B) a compound activating the transition metal compound (A), in which the steps (a) and (b) may be carried out in any order, and the resulting propylene polymer composition contains the propylene (co)polymer (a) in an amount of 20 to 90% by weight and the ethylene copolymer (b) in an amount of 10 to 80% by weight and has MFR, as measured at 230.degree. C. under a load of 2.16 kg, of 0.01 to 500 g/10 min; and a propylene polymer composition prepared by this process. The process according to the invention can prepare a propylene polymer composition having excellent rigidity, heat resistance and impact resistance.

Abstract: Disclosed is a cycloolefin copolymer composition (C) obtained by copolymerizing an .alpha.-olefin of two or more carbon atoms (a) and a specific cycloolefin (b) in the presence of an aromatic ring-containing vinyl hydrocarbon/conjugated diene copolymer or a product of hydrogenation thereof (A) which has an intrinsic viscosity (.eta.) of 0.5 to 5.0 dl/g; at least one glass transition temperature (measured by DSC) of lower than 15.degree. C.; polymerizable carbon-to-carbon double bonds in an amount of 2 to 150 in terms of iodine value; and a refractive index n.sub.D (A) of 1.50 to 1.65. In the composition (C), the component (A) is contained in an amount of 1 to 40% by weight, and a difference .DELTA.n.sub.D between the refractive index n.sub.D (A) of the component (A) and a refractive index n.sub.D (B) of a cycloolefin copolymer component (B) obtained by copolymerizing the .alpha.-olefin (a) and the cycloolefin (b) in the absence of the component (A) is not more than 0.015.

Abstract: The semiaromatic polyamide of the invention comprises 40 to 90% by mol of (A) recurring units derived from terephthalic acid and an aliphatic diamine of 4 to 12 carbon atoms, 0 to 50% by mol of (B) recurring units derived from isophthalic acid and an aliphatic diamine of 4 to 12 carbon atoms, 0 to 60% by mol of (C) recurring units derived from an aliphatic dicarboxylic acid of 4 to 18 carbon atoms and an aliphatic diamine of 4 to 12 carbon atoms and 0 to 50% by mol of (D) recurring units derived from a lactam or an aminocarboxylic acid of 6 to 20 carbon atoms, and has a content of boiling water-soluble components (MO components) of not more than 0.25% by weight. The semiaromatic polyamide has a low content of the MO components, so that mold contamination hardly brought about in the molding process, and also molded articles of good heat resistance can be produced.

Abstract: A method for producing aryl alkyl hydroperoxides which comprises selectively oxidizing an aryl alkyl hydrocarbon having the formula: ##STR1## wherein P and Q are hydrogen or an alkyl and may be the same or different from each other; x is an integer of 1-3; and Ar is an aromatic hydrocarbon group having a valence of x, with an oxygen-containing gas in the presence of a transition metal complex which contains, as a ligand, a cyclic polyfunctional amine compound having at least three nitrogen atoms in the ring forming molecular chain or an open chain polyfunctional amine compound having at least three nitrogen atoms in the main chain of the molecule.

Abstract: A process for preparing an olefin polymer comprising the steps of: preparing an olefin polymer ?I! by polymerizing or copolymerizing an olefin in the presence of an olefin poymerization catalyst comprising a specific solid titanium catalyst component ?A!, a specific organoaluminum compound catalyst component ?B! and a specific electron donor catalyst component ?C!; preparing an olefin polymer ?II! by polymerizing or copolymerizing an olefin in an polymerizer different from that for the polymerization of the above step in the presence of an olefin poymerization catalyst comprising a specific solid titanium catalyst component ?A!, a specific organoaluminum compound catalyst component ?B! and a specific electron donor catalyst component ?D!; and then allowing the resulting olefin polymer ?I! and the resulting olefin polymer ?II! to coexist in one polymerizer to further polymerize or copolymerize an olefin.

Abstract: A multi-layer pipe has an innermost layer formed of a butene polymer composition. At least one other layer is formed of a polyolefin resin composition comprising (A) 95-5 parts by weight of a polyolefin resin, (B) 5-95 parts by weight of a filler, and (C) 0.1-10 parts by weight per 100 parts by weight of components (A) and (B) combined of a modified polyolefin resin. This multi-layer pipe undergoes minimal elongation by heat so that it is free from troubles by thermal deformation even when high temperature fluid is passed therethrough, has high rigidity, and is thus suitable as plumbing for cold and hot water.

Abstract: Biaxially oriented films from high molecular weight polyethylene are characterized by a gas permeable structure formed from random-arranged microfibrils. The films have coefficients of static friction and kinetic friction of not more than 1.0. The biaxially oriented films are further characterized by service smoothness as well as tensile (tangent) modulus and tensile strength. The films may be used for lamination, filter, or for packaging for moisture absorbers. The biaxially oriented films may be obtained by extracting a hydrocarbon plasticizer from a sheet formed from the high molecular weight polyethylene and a hydrocarbon plasticizer, stretching the resulting sheet to obtain an oriented film having a specific surface area of at least 70 m.sup.2 /g and a fibril structure, and heating the oriented film under a standard length constraint to reduce the oriented film in specific area by at least 20 m.sup.2 /g.

Abstract: The present invention provides an ethylene copolymer comprising constituent units (a) derived from ethylene and constituent units (b) derived from an .alpha.-olefin having 3 to 20 carbon atoms, the ethylene copolymer being characterized in that(A) the ethylene copolymer has a density (d) of 0.86 to 0.95 g/cm.sup.3 ;(B) the ethylene copolymer has a MFR of 0.001 to 50 g/10 min as measured at a temperature of 190.degree. C. and a load of 2.16 kg;(C) the melt tension (MT) and MFR of the ethylene copolymer satisfy the relationlog MT>-0.66log MFR+0.6; and(D) the temperature (T) at which the exothermic curve of the ethylene copolymer measured by a differential scanning calorimeter (DSC) shows the highest peak and the density (d) satisfy the relationT<400d-250.

Abstract: The present invention provides processes for preparing olefin polymers, by which olefin polymers composed of a propylene block copolymer component and an ethylene/.alpha.-olefin copolymer component are directly prepared by polymerization and olefin polymers excellent in impact resistance as well as in mechanical strength such as rigidity, moldability and heat resistance can be prepared. In the processes of the invention, a step (i) for preparing a crystalline polypropylene component and a step (ii) for preparing a low-crystalline or non-crystalline ethylene/.alpha.-olefin copolymer component are carried out in an arbitrary order using an olefin polymerization catalyst to form a propylene block copolymer component; then another catalyst component is added to the polymerization system; and a step (iii) for preparing a low-crystalline or non-crystalline ethylene/.alpha.-olefin copolymer component is carried out.

Abstract: In accordance with the present invention, there are provided an olefin polymerization catalyst comprising an organoaluminum oxy-compound (A), a transition metal compound (B) and a hydrogenated organoaluminum compound (C); a solid olefin polymerization catalyst comprising the above-mentioned components (A), (B), (C) and a carrier (D); a prepolymerized catalyst formed by prepolymerization of olefin on a catalyst component comprising the above-mentioned components (A), (B), (C) and (D); an olefin polymerization catalyst comprising the above-mentioned solid olefin polymerization catalyst or the above-mentioned prepolymerized catalyst and an organoaluminum compound; and a method for the polymerization of olefin which comprises polymerizing olefin in the presence of the above-mentioned catalysts.

Abstract: A novel unsaturated copolymer of ethylene comprises a random copolymer of (i) ethylene, (ii) an .alpha.-olefin of 3 to 20 carbon atoms and (iii) at least one straight chain or branched chain nonconjugated triene or tetraene having one vinyl group in the molecule, which contains 30-92% by mol of ethylene units (i), 6-70% by mol of .alpha.-olefin units (ii) and 0.1-30% by mol of triene or tetraene units (iii), and which has a molar ratio of ethylene units (i) to .alpha.-olefin units (ii) of 40/60 to 92/8 (ethylene units (i)/.alpha.-olefin units (ii)) and an intrinsic viscosity (.eta.), measured in Decalin at 135.degree. C., of 0.05 to 10 dl/g. This novel unsaturated copolymer of ethylene is excellent in weathering resistance, heat resistance and ozone resistance and has a high vulcanizing rate.

Abstract: The names of a plurality of polyolefine resins are previously registered as index data in a name data base. An optimal operational pattern is stored in an operational pattern table for each combination of the name of a current resin under production and the name of a target resin to be produced. The optimal operation pattern is selected based on the name of the current resin under production and the name of the next target resin to be produced. Based on the selected optimal operational pattern, resin-type change control is executed.

Abstract: A process for producing a polyethylene terephthalate in which the amount of the oligomers, such as cyclic trimer etc., is lower and which causes metal mold staining to occur difficultly. The process comprises an esterification stage in which dicarboxylicacids including mainly terephthalic acid or ester-forming derivatives of such acids are esterified with glycols including mainly ethylene glycol or with ester-forming derivatives of such glycols; a liquid phase polycondensation stage in which the esterified product obtained in the esterification stage is subjected to a polycondensation in a liquid phase containing a polycondensation catalyst and having a content of an alkaline solubilizing agent of 0.

Abstract: To realize compactness of an inductance element such as choke coil or the like, an inductance element is provided which is composed of a magnetic core having a central hollow portion defined by a magnetic alloy thin strip, and a lead line disposed to pass through the hollow portion of the magnetic core. A specific magnetic permeation .mu. of said magnetic core is in the range of 100 to 10,000.

Abstract: The invention provides a polyolefin drug packaging material characterized in that the content, in the polyolefin, of substances containing 12 to 26 carbon atoms is not more than 150 ppm. The packaging material of the invention is useful because the risk of its reacting with and adversely affecting the drug packaged therewith is minimum.

Abstract: In the production of polyethylene naphthalate of the present invention, the esterification reaction between naphthalenedicarboxylic acid and ethylene glycol is conducted while causing water to be present in a reaction system from a start of reaction, in the presence of at least one catalyst selected from the group consisting of nitric, carboxylic, phosphoric and hydrogenphosphoric acid metal salts and alkyl amines according to necessity, to thereby attain an esterification ratio of 45 to 80%, so that a liquid mixture of naphthalenedicarboxylic acid esterification reaction products containing naphthalenedicarboxylic acid, carboxyl-hydroxyethoxycarbonylnaphthalene and bis(hydroxyethoxycarbonyl)naphthalene is obtained. Subsequently, a crystallized reaction product is separated from this liquid mixture to thereby obtain a mixture of esterification reaction products. Thereafter, this mixture having ethylene glycol added thereto according to necessity is subjected to polycondensation.

Abstract: Presence of a catalyst formed from (A) a transition metal compound comprising (A-1) a transition metal atom, (A-2) a hetero atom-containing ligand containing a heteroatom selected from oxygen, sulfur, nitrogen and phosphorus capable of forming a bond with the transition metal atom, and (A-3) a ligand having a conjugated .pi. electron through which the ligand can be bonded to the transition metal atom (A-1), and (B) an aluminoxane. The transition metal compound is pre-treated with (C) an organometallic compound, or (D) a halogen-containing inorganic compound of an element of Group III, IV or V of the periodic table in an organic solvent.

Abstract: Disclosed is a process for preparing an ethylene-.alpha.-olefin-nonconjugated polyene random copolymer comprising random copolymerizing (a) ethylene, (b) an .alpha.-olefin of 3 or more carbon atoms and (c) a nonconjugated polyene in the presence of a metallocene catalyst containing a specific metallocene compound. The ethylene-.alpha.-olefin-nonconjugated polyene random copolymer prepared by the process has such properties that (i) the copolymer contains units derived from ethylene (a) and units derived from the .alpha.-olefin of 3 or more carbon atoms (b) in a molar ratio of 40/60 to 95/5 ?(a)/(b)!, (ii) the iodine value is 1 to 50, (iii) the intrinsic viscosity (.eta.) is more than 0.1 dl/g and less than 8.0 10 dl/g, (iv) the intensity ratio D of T.alpha..beta. to T.alpha..alpha. in the .sup.13 C-NMR spectrum, T.alpha..beta./T.alpha..alpha., is not more than 0.5, (v) the B value is 1.00 to 1.50, (vi) the glass transition temperature Tg is not higher than -50.degree. C., and (vii) the ratio g.eta.

Abstract: A short wavelength light source mainly comprises a semiconductor laser for pumping a laser medium, a birefringence filter for controlling or stabilizing the waveform by applying an optical feedback to the semiconductor laser to feed back only light of specific wavelength, lens systems for focusing the pumping light, and an optical resonator composed of a laser medium formed of Nd:YAG doped with 1% of Nd and a nonlinear optical element formed of KNbO.sub.3. The birefringence filter is structured as a Lyot filter, and is composed of a birefringence element made of 2 mm thick non-doped YVO.sub.4, a polarizer, and a birefringence element made of 4 mm thick non-doped YVO.sub.4.This constitution realizes a short wavelength light source achieving a single longitudinal mode oscillation while maintaining a high output, small in size, superior in efficiency, and excellent in wavelength stability.

Abstract: In a gas phase olefin polymerization, an olefin is continuously fed to a fluid bed reactor in which a metallocene catalyst is present. At least one compound selected from water, alcohols and ketones is added in a specified amount simultaneously with the feeding of the olefin. Thus, an olefin polymer having a satisfactory drop second count index as defined by the below indicated formula is produced: ##EQU1## wherein t.sub.0 and t respectively represent a flow time measured in the flow test according to ASTM D-1775 of the olefin polymer obtained when none of the water, alcohols and ketones is incorporated in the reactor, and when at least one compound of water, alcohols and ketones is incorporated in the reactor. The flowability of the polymer formed in the reactor is excellent, so that blocking, bridging and the like do not occur during the gas phase polymerization. Thus, it is feasible to stably produce a (co)polymer having excellent particle properties in high yield for a prolonged period of time.