Abstract: Flexible polyurethane foams are made from isocyanate containing prepolymers where the isocyanate is a mixture of diphenylmethane diisocyanate (MDI) and polymeric forms of MDI. The isocyanate mixture has a functionality greater than 2.0. The prepolymer is an isocyanate capped polyol or mixture of polyols where the polyols are diols or triols having at least 50% by weight oxyethylene groups. The foams are made by reacting water with the prepolymer and fire retardant materials can be added to the reaction mixture to produce fire retardant foams. The foams have improved physical properties and flammability resistance.

Abstract: A drying chamber for water laden foams supports the foam structure on a porous support and warm air is forced through the foam to dry it. An air impervious mask on the porous support around the object insures that all the air only flows through the object. Multiple objects can also be dried and loaded outside the drying chamber.

Abstract: A fire-retarding polyurethane foam is applied to the interior surfaces of a mine such as mine shafts, entries and tunnels. The coating is applied by spraying a mixture of foam-forming ingredients including a hydrophilic polyoxyalkylene urethane prepolymer and a large amount of an aqueous slurry containing a phosphorous compound, alumina trihydrate and a char-forming material such as starch or wood cellulose. The foam coating acts as a protective sealant, and it can also be applied on other surfaces where insulation and fire retardancy are desired.

Abstract: Improved hydrophilic crosslinked polyurethane foams are prepared by reacting (a) an isocyanate-capped polyoxyethylene prepolymer with (b) at least 20 moles of water per mole of NCO groups in the presence of (c) alumina hydrate, (d) a phosphorus fire-retardant additive and (e) an organic carbon compound which serves to react with phosphate anions at high temperatures (e.g., in the presence of a flame) and reinforces the char provided by combustion of the foam.

Abstract: The invention disclosed relates to a new polyurethane composition having improved flame retardance and to a method for preparing same. The present composition includes a hydrophilic polyurethane having alumina hydrate and a phosphorus containing compound disposed therein.

Abstract: The invention disclosed relates to a new polyurethane composition having improved flame retardance and to a method for preparing same. The present composition is prepared by using a suspending agent and a surfactant. The suspending agent may be either a surfactant or an appropriate polymer, but to control the cellular structure, a surfactant that does not perform as a suspending agent is desirable. The resultant composition may be sprayed through a high pressure spray gun while permitting formation of heavily loaded flame retardant urethane foams which are neither dusty nor lose solids upon washing.

Abstract: The adduct of a cyclophosphonitrilic chloride (PNCl.sub.2).sub.3 and hexahylphosphoramide (Me.sub.2 N).sub.3 PO when reacted with an alcohol yields a reaction product that is useful as an additive to general purpose polyester resins enhancing the resin's fire retardant characteristics.

Abstract: The adduct of phosphorous oxychloride and hexamethylphosphoramide and alkoxy derivatives thereof useful for enhancing the fire retardancy of polyesters and a method of enhancing the fire retardancy of general purpose polyester resins through the combination therewith of an alkoxy derivative of the adduct of phosphorous oxychloride and hexamethylphosphoramide.

Abstract: The adduct of phosphorous pentachloride (PCl.sub.5) and hexamethylphosphoramide ((Me.sub.2 N).sub.3 PO) and alkoxy derivatives thereof useful for enhancing the fire retardancy of polyesters and a method of enhancing the fire retardancy of general purpose polyester resins through the combination therewith of the aforedescribed alkoxy derivative.

Abstract: The adduct of phosphorous oxychloride and hexamethylphosphoramide and alkoxy derivatives thereof useful for enhancing the fire retardancy of polyesters and a method of enhancing the fire retardancy of general purpose polyester resins through the combination therewith of an alkoxy derivative of the adduct of phosphorous oxychloride and hexamethylphosphoramide.

Abstract: The adduct of phosphorous pentachloride (PCl.sub.5) and hexamethylphosphoramide ((Me.sub.2 N).sub.3 PO) and alkoxy derivatives thereof useful for enhancing the fire retardancy of polyesters and a method of enhancing the fire retardancy of general purpose polyester resins through the combination therewith of the aforedescribed alkoxy derivative.

Abstract: The adduct of hexamethylphosphoramide and a cyclophosphonitrilic chloride, PNCl.sub.2).sub.n.sup.. [(CH.sub.3).sub.2 N].sub.3 PO, useful for enhancing the fire retardancy of epoxy resins and a method for enhancing the fire retardancy of epoxy resins through the combination therewith.