Abstract: A copolyester film having a planar orientation of from 0.04 to 0.15 is disclosed, wherein said copolyester has a reduced viscosity of from 0.8 dl/g to 1.6 dl/g and comprises dicarboxylic acid components including terephthalic acid as the main component, 1,4-butanediol, and diol components including at least one kind of diol represented by following formula (I), wherein when the content of the diol of the formula (I) in which m is 2 is less than 0.2 mole % based on all the acid components, the content of 1,4-butanediol is from 55 mole % to 85 mole % and the content of the diol of the formula (I) in which m is 1 is from 15 mole % to 45 mole % in 100 mole % of the total diol components excluding the diol of the formula (I) in which m is 2; and when the content of the diol of the formula (I) in which m is 2 is from 0.

Abstract: A polyoxymethylene composition useful for producing weather-resistant molded articles comprising 60-95% by weight of a polyoxymethylene, a methacrylic acid ester polymer, and a pigment, a dye or a mixture thereof. The weather-resistant molded articles obtained therefrom.

Abstract: A process for polymerizing an .alpha.-olefin which comprises contacting the .alpha.-olefin at a temperature of about 10.degree. C. to about 100.degree. C. with a catalyst comprising a slurry component (A) and an organometallic component (B), the component (A) being obtained, without intermediate or final solids separation, by reacting (1) a slurry reaction mixture produced by reacting one mol of (i) a hydrocarbon-soluble organomagnesium component of the general formulaM.alpha.Mg.beta.R.sub.p.sup.1 R.sub.q.sup.2 X.sub.r Y.sub.sor of the reaction product of M.alpha.Mg.beta.R.sub.p.sup.1 R.sub.q.sup.2 X.sub.r Y.sub.s with at least one electron donor selected from the group consisting of ethers, thioethers, ketones, aldehydes, carboxylic acids or derivatives thereof, alcohols, thioalcohols and amines, with 0.1 to 10 mols of (ii) a chlorosilane compound of the formulaH.sub.a SiCl.sub.b R.sub.4-(a+b).sup.10at a temperature of about 20.degree. C. to about 150.degree. C.

Abstract: A catalyst suitable for use in the polymerization of olefins is disclosed. This catalyst contains:[A] a solid catalyst component obtained by calcining (a) a zirconium compound represented by the general formula:Zr(OR.sup.0).sub.n A.sub.4-nwherein R.sup.0 is a hydrocarbon group having 1 to 20 carbon atoms; A is a halogen atom, a carboalkoxy group, a carboxyl group, an acylalkenate, or a hydrocarbon group having 1 through 20 carbon atoms; and n is a number of 0 through 4; and (b) a chromium compound, supported on an inorganic oxide carrier;[B] an organometallic compound component.

Abstract: A catalyst suitable for use in the polymerization of olefins is disclosed. This catalyst contains:[A] a solid catalyst component obtained by calcining a reaction product of (a) at least one compound selected from an amine compound, a phosphoric acid amide, a hydrocarbyloxy compound of titanium, vanadium, hafnium or zirconium, and a germanium compound having the general formula:R.sup.1 R.sup.2 R.sup.3 R.sup.4 Gewherein (i) R.sup.1, R.sup.2 and R.sup.3 are each independently a hydrocarbon group having 1 through 10 carbon atoms, and R.sup.4 is a hydrogen atom, a halogen atom, a --OH group, or a --OGeR.sup.1 R.sup.2 R.sup.3 group, or (ii) R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are each independently --OR.sup.5 wherein R.sup.5 is a hydrocarbon group having 1 through 10 carbon atoms, or a halogen atom, and a tin compound having the general formula:R.sup.1 R.sup.2 R.sup.3 R.sup.6 Snwherein R.sup.1, R.sup.2 and R.sup.3 are the same as defined above and R.sup.

Abstract: Catalysts for polymerization of olefin which comprise a solid catalyst component (A) and an organometallic compound with a heterocyclic carboxylic acid ester (B), wherein the solid catalyst component (A) is obtained by reacting or/and grinding a special magnesium compound (1), a titanium halide (2) and a carboxylic acid ester (3); and the heterocyclic carboxylic acid ester is N-, S- or O-containing heterocyclic compound, and processes for polymerization of olefin employing such a catalyst.

Abstract: A catalyst comprising (A) a solid catalyst component obtained by reacting a titanium compound having a hydrocarbyloxy group with an organoaluminum compound in the presence of an ether to give a liquid material or to give a solid titanium component (a) which is solubilized by addition of a tetravalent titanium halide with or without an ether without separation or after separation from the reaction mixture, and heat treating the liquid material at a temperature of 70.degree. to 180.degree. C. with or without addition of a tetravalent titanium halide, and (B) an organoaluminum compound is effective for polymerization or copolymerization of olefins with high stereoregularity and has high polymerization activity.

Abstract: Catalysts for polymerization of olefin which comprise a solid catalyst component (A) and an organometallic compound with a heterocyclic carboxylic acid ester (B), wherein the solid catalyst component (A) is obtained by reacting or/and grinding an organomagnesium compound (1), of the formulaM.sub..alpha. Mg.sub..beta. R.sub.p.sup.1 R.sub.q.sup.2 X.sub.rwherein.alpha., p, q and r each independently .gtoreq.0,.beta.>0,p+q+r=m.alpha.+2.beta.M is Al, Zn, B or Be,m is the valence of M,R.sup.1 and R.sup.2 are the same or different hydrocarbon groups having 1-20 carbon atoms, andX is a halogen atom,or of the reaction product of M.sub..alpha. Mg.sub..beta. R.sub.p.sup.1 R.sub.q.sup.2 X.sub.r with an electron donor, with 0.01 to 100 moles of (ii) a chlorosilane compound containing Si-H bonds and of the formulaH.sub.a SiClR.sub.4-(a+b).sup.3wherein0<a.ltoreq.

Abstract: Novel high active catalysts useful for highly stereospecific polymerization of olefin which enables to produce polymer of low content of catalyst residue, and of good grain size having a high stereoregularity can be obtained by a combination of [A] a solid catalyst component obtained by reacting and/or grinding a specified organomagnesium component (i) with a specified chlorosilane compound containing Si-H (ii) to obtain a solid (1) and reacting said solid (1) with a titanium compound containing at least one halogen atom (2) and a carboxylic acid or a derivative thereof (3) and [B] a component consisting of an organometallic compound and a carboxylic acid or a derivative thereof. The organomagnesium component is of the formulaM.sub..alpha. Mg.sub..beta. R.sub.p.sup.1 R.sub.q.sup.2 X.sub.r Y.sub.swherein .alpha. is a number of 0 or greater than 0; .beta.>0, p, q, r, and s are each a number of 0 or greater; p+q+r+s=m.alpha.+2.beta.