Polyol premixes and thermally insulating rigid polyurethane foams, such as those that can be used as a thermal insulation medium in the construction of refrigerated storage devices, are disclosed. A polymer polyol having a OH number of greater than 260 mg KOH/g is utilized. The resulting polyurethane foams can exhibit improved thermal insulation properties without sacrificing other important physical and processing properties.

Disclosed are ionomers of co-polymers of vinylidene substituted aromatic monomers and unsaturated compounds containing acid groups crosslinked by the residue of one or more metal salts and/or metal oxides of a metal having a valence of 2 or greater. The crosslinks are reversible and the weight average molecular weight of the copolymer of one or more vinylidene aromatic monomers and one or more unsaturated acids may be substantially the same after the crosslinking is reversed as it is before crosslinking. A portion of the chains of the copolymer of one or more vinylidene aromatic monomers and one or more unsaturated acids are crosslinked with other chains of the copolymer of one or more vinylidene aromatic monomers and one or more unsaturated acids. Disclosed are methods of preparing such ionomers

The process of foaming a polyolefin, e.g., polyethylene, composition using as a nucleator a combination an azodicarbonamide (ADCA) and a fluororesin at a ADCA: fluororesin weight ratio of 60:40 to 20:80. The synergic effect between these two nucleating agents results in a higher nuclei density and a foamed product with a smaller cell size as compared to processes using and products produced by the use of neat PTFE or neat ADCA alone as the nucleating agent.

A process of making a polyurethane or polyisocyanurate foam comprises the step of mixing under low pressure: (A) An isocyanate; (B) A compound reactive with the isocyanate, e.g., a polyol; (C) A liquid blowing agent; and (D) Carbon dioxide.

There is provided a method of producing a foamed molded product, including: plasticizing and melting a resin material containing a thermoplastic resin and a chemical foaming agent in a plasticizing cylinder in which a screw is provided, to provide a molten resin containing the chemical foaming agent; supplying a fluid with a fixed pressure into the plasticizing cylinder to pressurize the molten resin; and performing foam molding of the molten resin. The resin material contains 0.1 to 2% by weight of the chemical foaming agent.

A foamable composition including a polypropylene-based copolymer and a polyolefin is disclosed. The composition can be used to make a stiff foam with a high closed-cell content. Methods for producing the composition and the foam are provided.

The presently disclosed subject matter is directed to a method of making a foam, specifically, the development of isocyanate-free foams using at least one unsaturated polyester. The at least one unsaturated polyester is a reaction product of at least one unsaturated cyclic anhydride, dicyclopentadiene, and at least one polyol. The disclosed formulation further comprises at least one reactive diluent and at least one initiator. The disclosed formulations are cured by a free radical mechanism.

A thermally expandable composition, including at least one polymer, cross-linkable by peroxide, at least one peroxide, preferably at least one antioxidant, at least one chemical blowing agent, and at least one activator, wherein the activator includes at least one compound selected from formula (I), ##STR00001##
wherein radicals R.sup.1 and R.sup.4 represent hydrogen atoms or monovalent alkyl radicals with 1 to 10 carbon atoms which optionally include oxygen atoms; R.sup.2 and R.sup.3 represent hydrogen atoms or monovalent alkyl radicals with 1 to 10 carbon atoms which optionally include oxygen atoms, nitrogen atoms, and/or aromatic moieties or R.sup.2 and R.sup.3 together form a divalent alkyl radical with 1 to 10 carbon atoms which optionally includes oxygen atoms, nitrogen atoms or aromatic moieties. The composition shows excellent properties in terms of expansion stability over a wide temperature range, can be expanded at temperatures below 150° C. and is suitable for baffle and/or reinforcement elements.

Methods and systems that include introducing blowing agent into a hopper of a polymeric foam processing system.

Polyol premixes and thermally insulating rigid polyurethane foams, such as those that can be used as a thermal insulation medium in the construction of refrigerated storage devices, are disclosed. A polymer polyol having a OH number of greater than 260 mg KOH/g is utilized. The resulting polyurethane foams can exhibit improved thermal insulation properties without sacrificing other important physical and processing properties.