Abstract: The thermal stability of alpha-substituted acrylate graft copolymers can be improved by (a) making a graft copolymer comprising a backbone of a propylene polymer material having graft polymerized thereto monomers comprising (i) a 1-3 C alkyl-substituted acrylic acid and (ii) an ester of a 1-3 C alkyl-substituted acrylic acid, wherein the total amount of polymerized monomers is about 20 to about 240 parts per hundred parts of the propylene polymer material and the amount of (i) is about 1 to about 20%, based on the total weight of monomers, and (b) removing any unreacted grafting monomer from the resulting grafted propylene polymer material, decomposing any unreacted initiator, and deactivating any residual free radicals in the material.

Abstract: Process for repairing plastic coatings of metal pipes that allows one to make the repair using only a flame as a source of heat, including the application of protective shields during specific operating phases of the process.

Abstract: Embossed sheets having improved grain retention can be made from a polyolefin composition containing a propylene polymer material and a partially crosslinked thermoplastic olefin elastomer composition. Large parts such as automobile door and instrument panels can be formed from these sheets.

Abstract: A radiation-resistant polyolefin composition which includes (i) a polyolefin; and (ii) a radiation-stabilizing amount of at least one aliphatic, unsaturated compound having at least one unsaturation site, the compound having a molecular weight of at least 200 and an iodine number of at least 25. Suitable aliphatic, unsaturated compounds include soybean oil, safflower oil, squalene, polybutadiene, a tertiary amine having at least one aliphatic, unsaturated fatty-acid-derived substituent, oleamide, calcium oleate, erucyl erucamide and glycerol monooleate. A saturated mobilizing compound is preferably included in the composition, which can advantageously be used in the manufacture of fibers, films, and medical devices such as syringes, tube assemblies, tissue culture flasks, and packaging film.

Abstract: A polymer composition for making molded parts including (1) a thermoplastic olefin, (2) a propylene polymer material, and (3) an oxidized polyethylene wax having an acid number of .gtoreq.15 mg KOH/g, a high molecular weight ethylene polymer, or mixtures thereof, wherein (2)+(3) equals at least 22.5 parts per hundred parts of the thermoplastic olefin, has a good paint adhesion/durability balance. Injection molded parts made from this composition have a unique morphology characterized by a continuous matrix phase and discrete particles of a dispersed phase having a specific aspect ratio near the surface of the part and a specific particle size in the core of the part.

Abstract: A ductile, gamma radiation resistant olefin polymer composition, including (a) an olefin in polymer, (b) an amount of N,N-dialkylhydroxylamine which is effective to increase the ductility of the composition, and (c) a polysiloxane which contains sterically hindered piperidino groups and which is present in an amount effective to increase the gamma radiation resistance of the composition. The composition may be used to manufacture sterilizable articles including food packaging and medical articles.

Abstract: Process for the production of a high tenacity propylene polymer fiber which comprises:spinning fiber from a molten propylene polymer composition consisting essentially of an olefin polymer (I) and a high molecular weight propylene polymer (II) having a branching index less than 1 and melt strength from 5 to 40 cN; said propylene polymer (II) being present in a concentration from 0.1 to 10% by weight with respect to the total weight of the composition; anddrawing the solid fiber thus obtained with a draw ratio greater than 4.5 when the spinning step is continuous and greater than 5 when the spinning step is discontinuous.

Abstract: Directly paintable polymer compositions contain (1) a thermoplastic olefin, (2) a propylene homopolymer or propylene copolymer with ethylene or a 4-8 C alpha-olefin, grafted with an anhydride of an aliphatic .alpha., .beta.-unsaturated dicarboxylic acid, (3) an oxidized polyethylene wax having a melting point of less than 116.degree. C. and an acid number of less than 40, (4) a functionalized polymer that reacts with the anhydride groups of the grafted polymers, and, optionally, (5) a polyolefin rubber grafted with an anhydride of an aliphatic .alpha., .beta.-unsaturated dicarboxylic acid, and (6) an ethylene polymer grafted with an anhydride of an aliphatic .alpha., .beta.-unsaturated dicarboxylic acid. The compositions are particularly useful for making injection molded parts such as automobile bumpers, and exhibit excellent paint adhesion and durability.

Abstract: Directly paintable polymer compositions contain (1) a thermoplastic olefin, (2) a maleic anhydride-grafted propylene homopolymer or random copolymer, (3) a maleic anhydride-grafted olefin polymer material, (4) a functionalized polymer that reacts with the maleic anhydride groups of the grafted polymers, and, optionally, (5) a maleic anhydride-grafted ethylene polymer. The amount of (2)+(3) or (2)+(3)+(5) is at least 16 parts but less than 27 parts per hundred parts of the thermoplastic olefin.

Abstract: Flame retarding additives prepared by way of reaction of:A) one or more nitrogenous organic compounds of a defined formula;B) P.sub.2 O.sub.5 ;C) H.sub.2 O.

Abstract: A gas phase process for producing olefin polymer graft copolymers, including providing a reaction apparatus having first and second reaction zones operatively connected to each other into which particles of an olefin polymer and a free-radical polymerizable monomer are fed while maintaining free-radical polymerization conditions and a substantial non-oxidizing environment in said zones and from which the grafted copolymer product is discharged. An apparatus suitable for practicing this process is also disclosed.

Abstract: An embrittlement-resistant polyolefin composition, including: (a) at least 80% by weight, based on the total weight of the polyolefin composition, of a crystalline polymer comprising either a propylene homopolymer having an isotactic index greater than 90 or a random copolymer of propylene and either ethylene or C.sub.4 -C.sub.10 1-olefins, (b) an elastomeric copolymer of ethylene and either propylene or butene-1, where the elastomeric copolymer is present in an amount sufficient to enhance the flexibility of the polyolefin composition, without adversely affecting the clarity of the polyolefin composition, and where the polyolefin composition has a heat distortion temperature of at least 60.degree. C. Optional components include a stabilizing amount of a hindered amine light stabilizer, an acid neutralizing agent, and a sorbitol-based compound. The composition may be used to manufacture medical articles and food packaging material which must be sterilized, either by irradiation or by autoclaving.

Abstract: A graft copolymer comprising a backbone of a propylene polymer material having a vinyl monomer graft polymerized thereto is produced by (1) treating a propylene polymer material with a free radical polymerization initiator, (2) treating the propylene polymer material with at least one grafting monomer capable of being polymerized by free radicals, in the presence of a polymerization rate modifier, and (3) removing any unreacted grafting monomer from the graft copolymerized propylene polymer material, decomposing any unreacted initiator, and deactivating any residual free radicals in the material. Use of the polymerization rate modifier increases the polymerization induction time on the polymer surface, consequently facilitating monomer diffusion into the interior of the polymer particles so that surface polymerization of the monomer is inhibited.

Abstract: A method and apparatus for the classification of solid particles, in particular powdery catalytic components for the polymerization of olefins, which comprises sending solid particles suspended in a transporting gas flow through a screening device. Immediately upstream to the screening device there is an auxiliary fluidized bed classifier, in which the top of the bed is at the level of the lower part of the screening device.

Abstract: Disclosed are polyolefin films suitable for packaging having Elmendorf values lower than 0.8N in both machine direction and cross direction are obtained from compositions comprising (percentages by weight):A) from 70% to 90% of a polyolefin matrix containing 30% of one or more crystalline propylene homopolymers and/or copolymers having a flexural modulus greater than or equal to 1800 MPa;B) from 10% to 30% of one or more mineral fillers.

Abstract: A graft copolymer comprising a backbone of a propylene polymer material having a vinyl monomer graft polymerized thereto is produced by (1) treating a propylene polymer material with a free radical polymerization initiator, (2) treating the propylene polymer material with at least one grafting monomer capable of being polymerized by free radicals, and (3) removing any unreacted grafting monomer from the graft copolymerized propylene polymer material, decomposing any unreacted initiator, and deactivating any residual free radicals in the material, wherein (1) and (2) are carried out in the presence of a continuous feed of nitric oxide. The nitric oxide reduces the build-up of polymer deposits on reactor walls and gas circulation loops while having almost no effect on the graft copolymerization reaction.

Abstract: A spunbonded material having improved tensile strength is made by (1) continuously extruding a propylene homopolymer or random propylene/ethylene copolymer having a melt flow rate of about 3 to about 30 g/10 min at a temperature above 500.degree. F. through a spinneret to form discrete filaments, (2) drawing the filaments to molecularly orient the polymer filaments, and (3) depositing the filaments in a substantially random manner onto a carrier belt to form a web. The propylene polymer contains an additives package that includes an organic phosphite, a hindered phenol compound, calcium stearate, and, optionally, a hydrotalcite compound.

Abstract: Depolymerization during melt processing of poly(methyl methacrylate) that is grafted onto a backbone of propylene polymer material is retarded by adding 0.025 parts to 5.0 parts of a hydroxylamine compound per hundred parts of the graft copolymer. The methyl methacrylate can be copolymerized with another monomer such as methylacrylate.

Abstract: Process for the production of a high tenacity propylene polymer fiber which comprises:spinning fiber from a molten propylene polymer composition consisting essentially of an olefin polymer (I) and a high molecular weight propylene polymer (II) having a branching index less than 1 and melt strength from 5 to 40 cN; said propylene polymer (II) being present in a concentration from 0.1 to 10% by weight with respect to the total weight of the composition; anddrawing the solid fiber thus obtained with a draw ratio greater than 4.5 when the spinning step is continuous and greater than 5 when the spinning step is discontinuous.

Abstract: Mixtures containing bitumen and at least one polymer selected from (A) an essentially atactic propylene homopolymer, (B) an amorphous propylene copolymer with a C.sub.4 -C.sub.10 .alpha.-olefin, and (C) an amorphous propylene copolymer with ethylene; the polymers (A) and (B) having the following characteristics:intrinsic viscosity (.eta.): greater than 1 dl/g;% (r)-% (m)>0, where % (r) is the percentage of the syndiotactic dyads, and % (m) is the percentage of the isotactic dyads;less than 2% of the CH.sub.2 groups are contained in the (CH.sub.2).sub.n sequences where n.gtoreq.2; andBernoulli index (B)=1.+-.0.2;the copolymer (C) having the following characteristics:the quantity of propylene in the copolymer (%P), expressed in mole percentage, and the EPE/(EPE+PPE+PPP) triad ratio satisfy the following equation:0.01 % P+EPE/(EPE+PPE+PPP).gtoreq.1;and less than 2% of the CH.sub.2 groups are contained in the (CH.sub.2).sub.n sequences where n is an even number.