摘要:
There is disclosed a homoplymer of an alkenylsilane having a syndiotactic structure and a copolymer of the alkenylsilane and an .alpha.-olefin. The polymer and the copolymer can be prepared by subjecting the alkenylsilane or the alkenylsilane and the .alpha.-olefin to addition polymerization in the presence of a transition metal compound having asymmetirically interconnected ligands or preferably in the presence of the transition metal compound and aluminoxane. The polymer and the copolymer can be used as a nucleating agent for a crystalline polypropylene.
摘要:
Disclosed is a syndiotactic propylene copolymer containing 0.01 to 40 mol % of olefin units containing --OH group in the side chain. Of absorption peaks attributed to the methyl groups of the propylene units on an absorption spectrum by .sup.13 C-NMR of the copolymer, the intensity of an absorption peak observed at about 20.2 ppm is 0.3 or more of the intensity of absorption peaks of all the methyl groups attributed to the propylene units. The copolymer is produced by copolymerizing propylene and an alkenylsilane or alkenylborane compound in the presence of a catalyst system comprising an asymmetric ligands-having transition metal compound and an aluminoxane, followed by heat-treating the resulting propylene-alkenylsilane copolymer in the presence of a trialkylamine oxide and KF.HF or oxidizing and decomposing the resulting propylene-alkenylborane compound copolymer. Also disclosed is a resin composition comprising the copolymer and other polyolefin(s).
摘要:
A poly-.alpha.-olefin of novel structure which is an addition polymer of an .alpha.-olefin having 4 carbon atoms or more, wherein (a) by the analysis of the peaks attributable to the side chain methylene groups directly bonded to the main chain in the .sup.13 C-NMR spectrum produced by the measurement in 1,2,4-trichloro-benzene, (i) a novel main peak not attributable to the isotactic structure thereof is positioned on the side of higher magnetic field than is the peak attributable to the isotactic structure, and (ii) the intensity of said main peak is 0.3 or more relative to the sum of the intensities of the total peaks attributable to the side chain methylene groups directly bonded to the main chain, and (b) the molecular weight measured by gel permeation chromatography and calculated as polypropylene is not less than 1,000.
摘要:
A method for preparing molded articles of a crosslinked polyolefin is here disclosed which comprises the steps of mixing polyolefin granules comprising polyolefin granules containing a hydrosilylation catalyst, polyolefin granules containing the copolymer of an alkenylsilane and an olefin, and if necessary, polyolefin granules containing neither the hydrosilylation catalyst nor the copolymer of the alkenylsilane and the olefin, and then heating, melting and molding the mixture in a molding machine.According to the present invention, the molded articles of the crosslinked polyolefin containing no residual crosslinking agent and having improved heat resistance and mechanical strength can be obtained by the easy method which comprises mixing the above-mentioned respective granules, and then heating, melting and molding the mixture.
摘要:
A method for preparing a decomposable film which comprises the steps of dispersing poly-.alpha.-methylstyrene or a polyalkylene carbonate in water, or preferably dissolving poly-.alpha.-methylstyrene or the polyalkylene carbonate in a solvent, dispersing the resulting solution in water, vaporizing the solvent so that the content of the solvent may be in the range of from 20 to 100% by weight based on the weight of poly-.alpha.-methylstyrene or the polyalkylene carbonate, applying the resulting aqueous emulsion, and then drying the same; and a method for preparing a metal film having a flat surface which comprises the steps of depositing a metal on the surface of the decomposable film, and then treating the film at a temperature higher than the decomposition temperature of the film.
摘要:
An .alpha.-olefin-alkenylsilane copolymer having steric regularity in which the side chains in the .alpha.-olefin unit substantially have the steric regularity, the content of alkenylsilane units is from 0.01 to 50% by weight, and the intrinsic viscosity measured in a tetralin solution at 135.degree. C. is 0.01 or higher. A method for preparing the above copolymer comprises the step of copolymerizing an .alpha.-olefin having 3 to 25 carbon atoms with an alkenylsilane in the presence of a catalyst comprising an aluminoxane and a transition metal compound containing a cyclopentadiene group or its derivative as a ligand.
摘要:
The invention relates to a block copolymer of propylene and a process for preparing the same comprising (a) polymerizing propylene or .alpha.-olefins mainly comprising propylene in the presence of a catalyst comprising a transition metal catalyst and an organometal compound; (b) copolymerizing .alpha.-olefins mainly comprising propylene and ethylene, wherein in at least one of steps (a) and (b) copolymerization is carried out with an alkenylsilane compound.
摘要:
An improved method for preparing block copolymers of propylene which comprises providing a polymerizer composed of at least two reaction vessels connected to one another, substantially homopolymerizing propylene in a first step and then copolymerizing ethylene and propylene in a second step in the presence of a stereoregular catalyst, characterized by carrying out the homopolymerization of propylene in the polymerizer composed of at least two reaction vessels connected to one another in series, then introducing the resulting polymer slurry into a countercurrent washing column and countercurrently washing the slurry with propylene, introducing the washed slurry withdrawn from the lower part of the washing column into a reaction vessel in the second step connected to the washing column and performing the polymerization of ethylene and propylene, of which ratio ranges from 15/85 to 95/5. According to this method, a block copolymer of propylene exhibiting excellent physical properties can be obtained efficiently.
摘要:
The present invention provides polyolefin resin compositions, comprising (i) a polymer containing an alkenylsilane compound and an inorganic filler and (ii) a polyolefin compound which provide molded articles having excellent Izod impact strength, tensile yield strength and stiffness and are also useful for the production of surface-coated molded articles.
摘要:
A syndiotactic polypropylene copolymer is disclosed which comprises 70 to 99.9 mole % of propylene and 0.1 to 30 mole % of an olefin other than propylene; in the 13C-NMR spectrum of the syndiotactic polypropylene copolymer, a ratio of the intensity of a peak at about 20.2 ppm to the sum of the intensities of the total peaks attributable to methyl groups in propylene units at about 19-22 ppm being 0.3 or more. Also disclosed are extrusion-molded high-transparency articles, especially films and sheets and blown films, obtained by the extrusion of a polypropylene substantially having a syndiotactic structure.