Abstract: A trihydrocarbyl aluminum is produced at a high yield by reacting an aluminum-magnesium alloy powder with a halogenated hydrocarbon. Prior to the reaction, the alloy powder is obtained by grinding treatment using a ball mill or a vibration ball mill. The reaction is conducted with agitation in the presence of abrasive particles or is conducted using a homogenizer without abrasive particles.

Abstract: 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.

Abstract: 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).

Abstract: 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.

Abstract: 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.

Abstract: An unwrapping apparatus for unwrapping a palletized and stretch-wrapped load, including at the front side thereof lower grippers and upper grippers to grip the lower edge and upper edge of a stretchable film of the load, respectively, and a cutter unit for vertically cutting the stretchable film. The unwrapping apparatus includes at the rear side thereof a carriage having a platen to press the top of a load, a pair of swing arms carrying the upper grippers, and a pair of auxiliary film separating swing arms to separate the stretchable film from the rear corner portions of the load when the film is removed from the load by the main swing arms. The main swing arms and the auxiliary swing arms prevent the articles from being pulled and moved by the stretchable film in contact with the articles and thus falling down from the separate sheet in particular.

Abstract: 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.

Abstract: 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.

Abstract: An unwrapping apparatus for unwrapping a palletized and stretch-wrapped load, the apparatus enables the prevention of the articles from falling off and easy disposal of the used stretchable film. The apparatus comprises first and second upright frames between which a load to be unwrapped is conveyed, the first upright frame including two lower grippers for gripping a lower edge of the stretchable film, and an elevated cutter unit having two pairs of pinch rollers and a heat cutter. The second upright frame includes a carriage having a platen to press the top of the load to be unwrapped and a pair of swing arms symmetrically arranged on either side of the platen and extending toward the first upright frame. Upper grippers are secured to the swing arms, respectively. The stretchable film can be gripped during the cutting and unwrapping of the load to maintain tension and prevent the articles in the load from falling off. In addition, the used stretchable film can be discharged in a compressed, compact form.

Abstract: 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.

Abstract: 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.