The present invention relates to the field of polyol components suitable for forming polyurethane foam, in particular two component polyurethane foam the resulting foams and methods for their production. The present inventors found gaseous hydrohaloolefin containing polyol components possessing improved shelf-life properties, in particular polyol components comprising a gaseous hydrohaloolefin blowing agent, a nitrogen catalyst and a tin catalyst, wherein the tin catalyst comprises a sulfur atom. The present inventors also found that the shelf-life is further improved if the nitrogen catalyst is at least partially protonated by reaction with an acid, such as an organic acid.

Foam wall structures and methods for making them are described. The wall structures include a frame, a foam panel overlying a front surface of the frame, and a polyurethane foam layer disposed in a cavity of the wall structure. The polyurethane foam layer has a density, as determined by ASTM D1622-14, of at least 44 kg/m.sup.3(2.75 lb/ft.sup.3) and exhibits ASTM E84-16 Class A flame spread and smoke development characteristics. The polyurethane foam layer is the cured reaction product of a polyurethane foam-forming composition that includes a polyisocyanate, an aromatic polyester polyol having a functionality of greater than 2.5 and an OH number of at least 300 mg KOH/g, which is present in an amount of at least 50% by weight, based on the total weight of the polyurethane foam-forming composition less the weight of the polyisocyanate, a catalyst, and a blowing agent composition. The blowing agent composition includes water and a hydrofluoroolefin.

This invention provides polyurethane foams containing a brominated flame retardant. Also provided are formulations and methods for preparing polyurethane foams containing a brominated flame retardant.

This invention provides polyurethane foams containing a brominated flame retardant. Also provided are formulations and methods for preparing polyurethane foams containing a brominated flame retardant.

A polymer composition with increased melt strength is disclosed. The polymer composition contains at least one polypropylene polymer combined with at least one melt strength modifier. The melt strength modifier can comprise a sorbitol derivative in an amount sufficient to change the melt strength characteristics and properties of the polymer. The polymer composition can be used in thermoforming processes and to produce polymer foams. The melt strength modifier can increase the melt strength of the polymer without having to induce branching in the polypropylene polymer.

Disclosed are bowing agent compositions, foamable compositions, foams, foaming methods and/or foamed articles comprising one or more C2 to C6 fluoroalkenes, more preferably one or more C3 to C5 fluoroalkenes, and even more preferably one or more compounds having Formula I as follows:

XCF.sub.zR.sub.3-z (I)

Where X is a C.sub.1, C.sub.2, C.sub.3, C.sub.4, or C.sub.5 unsaturated, substituted or unsubstituted radical, each R is independently Cl, F, Br, I or H, and z is 1 to 3, it generally being preferred that the fluoroalkene of the present invention was at least four (4) halogen substituents, at least three of which are F and even more preferably none of which are Br.

A polyurethane foam, polyisocyanurate foam or polyurea foam is obtainable from the reaction of a mixture comprising A) a compound reactive towards isocyanate (NCO-reactive compound); B) a blowing agent selected from the group comprising linear, branched or cyclic C1 to C6 hydrocarbons, linear,branched or cyclic C1 to C6 fluorocarbons, N.sub.2, O.sub.2, argon and/or CO.sub.2, where the blowing agent B) is present in the supercritical or near-critical state; C) a polyisocyanate; D) an amphiphilic isocyanate; and E) optionally a surfactant and F) optionally other auxiliaries and additives. The invention further relates to the production of this polyurethane foam, where the blowing agent is emulsified in the isocyanate component containing amphiphilic isocyanate.

The use of an Ostwald hydrophobe in the production of polymer foams, preferably polyurethane foam, in particular rigid polyurethane foam, from liquid reaction mixtures, to retard cell ageing, in particular to retard cell ageing caused by Ostwald ripening, is described.

Isocyanate-reactive compositions that include a hydrofluoroolefin blowing agent, polyurethane foam-forming compositions, as well as spray-applied polyurethane foams formed therefrom that can provide structural support to wall structures and can also exhibit ASTM E84-16 Class A flame spread and smoke development characteristics at a foam thickness of 4 inches.

A preparation method of a high-rate foamed polylactic acid (PLA) sheet includes first-stage extrusion, second-stage extrusion, and foamed sheet extrusion. The method requires the following raw materials in parts by mass: 88 to 94 parts of PLA, 1 to 2 parts of a nucleating agent, 2 to 5 parts of a foaming agent, and 2 to 5 parts of an additive. The new method effectively solves the problems of low foaming rate, low strength, and the like in the industrial production using carbon dioxide, and a prepared PLA sheet with high foaming rate and excellent surface performance can be used in the fields of food packaging, disposable fully-degradable lunch boxes, and the like.