Disclosed herein are ethylene-based polymers having low densities and narrow molecular weight distributions, but high melt strengths for blown film processing. Such polymers can be produced by peroxide-treating a metallocene-catalyzed resin.

A blow-molded plastic structure has a hollow interior portion formed during a blow-molding process, and includes first and second outer portions that are spaced apart from each other, with the hollow interior portion disposed there between. The structure includes a pattern of structural stiffening features that are integrally formed in the second outer portion. The pattern of structural stiffening features includes a plurality of tripodal depressions disposed in rows and columns and a plurality of convex regions disposed in rows and columns between the plurality of tripodal depressions. Each convex region has a maximum height between the first and second outer portions. Each of the tripodal depressions extends into the hollow interior portion, includes three indentations disposed adjacent the first outer portion, and includes an island spaced away from the first outer portion. The island has three sides, each of which is disposed adjacent one of the three indentations.

A parison for being blow molded into a medical balloon for a catheter includes a first tubular layer having a functional modification and a second tubular layer adapted for bonding with the first tubular layer to form the blow molded balloon. Related methods are also disclosed.

A method for manufacturing an injection-molded article, preferably a preform (11) of a bottle (1), in particular an aerosol bottle, made of a crystallizable polymer material, this article having at least one crystallized part (3), in particular a neck, and preferably a tubular body (14) closed at one end (16), the method comprising the following steps: a) producing an injection-molded article, preferably an injection-molded preform (11), by injecting the crystallizable polymer into a mold, b) crystallizing said part (3) of the injection-molded article, in particular of the injection-molded preform, by heating and then cooling the latter, wherein, in said method, between step a) and step b), the injection-molded article, in particular the injection-molded preform (11), is held for a sufficient duration under storage conditions such that it undergoes moisture uptake of at least 0.4% by weight.

A formulation for producing a polymeric material including polypropylene, a chemical blowing agent, and optional components as described.

The invention concerns a bottle (1) molded from at least one thermoplastic polymer of at least one Furan Dicarboxylic Acid (FDCA) monomer, preferably 2,5-Furan Dicarboxylic Acid (2,5-FDCA) monomer, and at least one diol monomer, preferably Monoethyleneglycol (MEG) monomer, said bottle, having a main axis (X), being provided with a body (5) and a bottom base (6) extending from a lower end of the body (5), The bottom base (6) comprises: —a peripheral seat (7) defining a laying plane (8); —a concave arch (10) which extends from the periphery of a central zone (11) of the bottom base (6) to the peripheral seat (7), said concave arch (10) having a rounded general shape with a concavity turned towards the outside of the container (1) and the middle point of the central zone (11) being named push-up (11a); —a series of reinforcing grooves (13) which extend radially from the central zone (11) to at least the peripheral seat (7); —base feet (14) located between two adjacent reinforcing grooves (13); According to the invention, the bottle bottom base (6) comprises a push-up height, defined as the height between the push-up (11a) and the laying plan (8), that is in the range of 7 to 10 mm for a bottle having a diameter (D) between 40 and 150 mm.

A polyethylene-based resin composition for injection stretch blow molding may include a copolymer of ethylene and one or more C4-C8 α-olefins. The composition may have a density, according to ASTM D792, that ranges from about 0.946 to 0.960 g/cm.sup.3 and a melt index (15), as measured according to ASTM D 1238 at 190° C. under a 5.0 kg load, ranging from about 5.0 to 50 g/10 min. A method of producing an article may include injection molding the composition to give a preform; and stretch-blowing the preform to provide the article.

In the manufacture of double-walled corrugated extruded pipe it is desirable to form an integral connecting cuff that is of a single wall thickness and typically of a large diameter. The mold blocks and process parameters for forming of the cuff as part of an otherwise double-walled pipe requires a transition as the cuff moves past the die outlets. The present invention allows for accurate sensing and control of air pressure and temperature as the cuff moves past the die outlets. Improvements in both the die tooling and the method of manufacture are disclosed.

A method for inflating a chamber in an article composed at least partially of polymer layers, such as thermoplastic layers. The method can allow for forming an aperture in a polymer layer, inflating a chamber or volume in fluid communication with the aperture, and then welding or sealing the chamber so that the inflation fluid is substantially retained in the chamber and/or does not escape via the aperture. In various aspects, the formation of the aperture, inflation of the chamber, and sealing of the chamber or aperture can be performed by a single tool and/or based on a single registration of the thermoplastic article with a tool. In some aspects, formation of the aperture is enabled in part by using a punch with a cupped surface that allows the top layer of a thermoplastic article to be breached without forming a hole in at least one lower layer.

A multi-layer direct blow bottle in which a metallic layer containing a metal pigment having an average thickness of not more than 1 μm dispersed in a resin is formed at a position where it is visible from the outer surface side.