摘要:
A process for producing a propylene//propylene/olefin block copolymer, characterized by using as a supported metallocene catalyst a solid product obtained by conducting, in this order, the step (a) of reacting an organic transition metal compound having two crosslinked conjugated &pgr;-electron ligands with an aluminoxane in an inert solvent, the step (b) of contacting the reaction product obtained in the step (a) with a finely particulate inorganic support in the presence of an inert solvent at 85 to 150° C., and the step (c) of washing the slurry containing a solid product yielded in the step (b) with an aliphatic hydrocarbon at least twice at −50 to 50° C.; and a propylene//propylene/olefin block copolymer produced by said process.
摘要:
A process for producing a modified polypropylene having a very high melt tension and superior stiffness and moldability, and a molded product obtained by using the modified polypropylene are provided.which process includes adding 0.05 to 10 millimols of a cross-linking auxiliary to 100 g of a linear polypropylene, mixing them, irradiating ionizing radiations to the mixture so as to give an absorbed dosage of 1 to 20 kGy, and successively heat-treating the resulting material at 80.degree. to 350.degree. C.,which modified polypropylene has(A) a degree of branching of substantially 1,(B) a relationship between its melt tension (MS) at 230.degree. C. and its intrinsic viscosity (.eta.) measured in tetralin at 230.degree. C. expressed by an inequalitylog (MS)>4.24.times.log [.eta.]-0.915, and(C) a percentage of extraction residue in boiling xylene of 1% by weight or less.
摘要:
A high molecular weight polyethylene prepared by preliminary polymerization is added at the time of main polymerization of an olefin, for example, propylene, to prepare an olefin (co)polymer composition comprising the above high molecular weight polyethylene finely dispersed as fine particles in the polyolefin, such as polypropylene, and a cross-linked structure is formed in the olefin (co)polymer composition. This process can provide a modified olefin (co)polymer composition improved in the strength in a molten state in terms of melt tension or the like and in crystallization temperature and excellent in moldability such as high-speed producibility, and a molded modified olefin (co)polymer composition excellent in properties such as heat resistance and rigidity.
摘要:
A linear, crystalline polypropylene having a branching coefficient of substantially 1, and a specified relation between melt-tensile strength and intrinsic viscosity, a specified relation between crystallization temperature and melting point, a boiling xylene-extraction residue % of 1 wt. % or less and if necessary, a specified ratio of weight average M.W./number average M.W.; a molded product from the above polypropylene; and a process for producing a polypropylene having the above polypropylene blended with di-2-ethylhexyl peroxydicarbonate, are provided, the above polypropylenes having a very high melt-tensile strength and crystallization temperature and also superior stiffness and moldability, to thereby broaden the restricted application fields of conventional polypropylene.
摘要:
A plastic molded product of olefin (co)polymer composition comprises 0.01-5.0 weight parts high molecular weight polyethylene with an intrinsic viscosity &eegr;E in the range of 15-100 dl/g measured in 135° C. tetralin and preferably 100 weight parts polypropylene. The high molecular weight polyethylene has an average particle size in the range of 1-5000 nm and is finely dispersed as fine granules in the polypropylene, so that high melt strength and high crystallization temperature are attained, enabling various molding methods to be performed with high speed productivity. Using the polymer composition, plastics such as a resin foam, a film, a sheet, a layered plastic article with a coated substrate surface, a hollow plastic article, an injection molded plastic article, a fiber, a nonwoven web or a continuous tube-shaped plastic are provided. The olefin (co)polymer composition is obtained by preparing high molecular weight polyethylene granules using e.g. a titanium transition metal compound catalyst, and adding these, e.g. as a polymerization catalyst of propylene, singly or together with a polyolefin preparing catalyst.
摘要:
An olefin (co-)polymer composition including 0.01 to 5.0 weight parts of high molecular weight polyethylene which is an ethylene homopolymer or an ethylene-olefin copolymer containing 50 weight % or more of an ethylene polymerization unit; and 100 weight parts of an olefin (co-)polymer other than the high molecular weight polyethylene, wherein said high molecular weight polyethylene has an intrinsic viscosity [.eta..sub.E ] of 15 to 100 dl/g measured in tetralin at 135.degree. C. or more, and said high molecular weight polyethylene exists as dispersed fine particles having a numerical average particle size of 1 to 5000 nm.
摘要:
A process for the production of a high stereoregular polypropylene wherein(a) an isotactic pentad (m m m m) is 0.950 to 0.995,(b) a syndiotactic pentad (r r r r) is 0 to 0.01,(c) a different bond due to 2,1- and 1,3-insertions of propylene monomer is 0 to 0.3 mol %,(d) an absence of a terminal double bond is confirmed,(e) a weight average molecular weight (Mw) is 50,000 to 1,000,000 and(f) a ratio (Mw/Mn) of the weight average molecular weight (Mw) to a number average molecular weight (Mn) is 1.5 to 3.8, (a) to (d) being determined from .sup.13 C NMR spectra, comprising polymerizing propylene in the presence of hydrogen using a catalyst comprising a chiral transition metal compound and an aluminoxane, the transition metal compound being represented by the formula of Q(C.sub.5 H.sub.4-m R.sup.1.sub.m) (C.sub.5 H.sub.4-n R.sup.2.sub.n)MXY wherein (C.sub.5 H.sub.4-m R.sup.1.sub.m) and (C.sub.5 H.sub.4-n R.sup.2.sub.n) represent a substituted cyclopentadienyl group; m and n are an integer of 1 to 3; R.sup.1 and R.sup.2 may be the same or different and each represents an alkyl group of 1 to 20 carbons; Q is a group capable of crosslinking (C.sub.5 H.sub.4-m R.sup.1.sub.m) and (C.sub.5 H.sub.4-n R.sup.2.sub.n) and represents a divalent, hydrocarbyl radical, an unsubstituted silylene group or a hydrocarbyl-substituted silylene group; M represents a transition metal selected from the group consisting of titanium, zirconium, and hafnium; X and Y may be the same or different and each represents a hydrogen, a halogen or a hydrocarbyl radical, and wherein said polymerization is performed by a slurry polymerization using an aliphatic hydrocarbon as a solvent or by a bulk polymerization using propylene as a solvent.
摘要翻译:一种制备高立构规则聚丙烯的方法,其中(a)全同立构五单元组(mmmm)为0.950-0.995,(b)间同立构五单元组(rrrr)为0至0.01,(c)由于2,1 - 和丙烯单体的1,3-插入为0〜0.3摩尔%,(d)不存在末端双键,(e)重均分子量(Mw)为50,000〜1,000,000,(f)a 重均分子量(Mw)与数均分子量(Mn)之比(Mw / Mn)为1.5至3.8,(a)至(d)由13 C NMR谱确定,包括在存在下聚合丙烯 使用包含手性过渡金属化合物和铝氧烷的催化剂的氢,所述过渡金属化合物由下式Q(C5H4-mR1m)(C5H4-nR2n)MXY表示,其中(C5H4-mR1m)和(C5H4-nR2n)表示 取代的环戊二烯基; m和n为1〜3的整数, R 1和R 2可以相同或不同,各自表示1〜20个碳的烷基; Q是能够交联的基团(C5H4-mR1m)和(C5H4-nR2n),代表二价烃基,未取代的亚甲硅烷基或烃基取代的亚甲硅烷基; M表示选自钛,锆和铪的过渡金属; X和Y可以相同或不同,各自表示氢,卤素或烃基,并且其中所述聚合通过使用脂族烃作为溶剂的淤浆聚合或通过使用丙烯作为溶剂的本体聚合进行。
摘要:
There are provided propylene-ethylene copolymers from which there are made molded articles having excellent heat resistance and films having both low temperature heat-sealing characteristics and stiffness, processes for the production thereof and molded articles. The propylene-ethylene copolymers contain 0.01-15 mol % of an ethylene unit and are characterized by that in the chain structure determined by NMR, triad (PEP), triad (EEE) and a ratio (N.sub..alpha..beta.) of all .alpha., .beta.-methylene carbons to all propylene units are in the specified range, a weight average molecular weight is 50,000-1,500,000 and a molecular weight distribution (Mw/Mn) is 1.2-3.8. The copolymers can be produced by copolymerizing ethylene and propylene in the presence of a catalyst in which the specified chiral transition metal compound (metallocene) and aluminoxane are combined.
摘要:
An IGBT has an emitter region, a top body region that is formed below the emitter region, a floating region that is formed below the top body region, a bottom body region that is formed below the floating region, a trench, a gate insulating film that covers an inner face of the trench, and a gate electrode that is arranged inside the trench. When a distribution of a concentration of p-type impurities in the top body region and the floating region, which are located below the emitter region, is viewed along a thickness direction of a semiconductor substrate, the concentration of the p-type impurities decreases as a downward distance increases from an upper end of the top body region that is located below the emitter region, and assumes a local minimum value at a predetermined depth in the floating region.
摘要:
A liquid sealed vibration isolating device has an elastically movable diaphragm capable of preventing elastic deformation of a relief valve to realize high damping while preventing a cavitation phenomenon. The relief valve is provided in the elastic movable diaphragm arranged in a partition member in order to open and close a leak passage so as to prevent occurrence of the cavitation phenomenon. The relief valve is integrally formed with a fixing portion of the elastic movable diaphragm. There is provided an upwardly open concavity that the relief valve faces. The relief valve is made thicker and provided with an opening and closing adjustment groove at a basal portion of its inclined wall. The opening and closing adjustment groove is formed with a locally thin bending portion functioning as a starting point of bending in an opening and closing operation of the relief valve.