Rigid spray foams

With amine initiators the so-called self-catalysed polyols are obtained, which are used in the formulation of rigid spray foam systems. The rigidity or stiffness of a foam is increased by aromatic initiators, such as Mannich bases derived from phenol, phenoHc resins, toluenediamine, or methylenedianiline... 

The product contains 12.6% phosphoms and has an OH number in the 450 mg KOH/g range. Fyrol 6 is used to impart a permanent Class 11 E-84 flame spread rating to rigid foam for insulating walls and roofs. Particular advantages are low viscosity, stabiHty in polyol—catalyst mixtures, and outstanding humid aging resistance. Fyrol 6 is used in both spray foam, froth, pour-in-place, and slab stock. 

Applications. The principal use for rigid polyurethane foams is for iasulation ia various forms utilized by a variety of iadustries. Lamiaates for resideatial sheatiag (1.2 to 2.5 cm thick with aluminum skins) and roofing board (2.5 to 10.0 cm thick with roofing paper skins) are the leading products with about 45 metric tons of Hquid spray systems also ia use. Metal doors iasulated by a pour-ia-place process coastitute another substantial use. 

Process and Equipment. Rigid polyurethane foam processes use Ihe same high or low pressure pumping, metering, and mixing equipment for flexible foams. Subsequent handling of the mixture is determined by the end product desired. Processes include lamination, pour-in-place, molding, bun stock, box loams, and spray. 

The bulk of the ngid polyurethane and polyisocyanurate foam is used in insulation. See also Insulation (Thermal) More than half (60%) of the rigid foam consumed in 1994 was in the form of board or laminate die remainder was used in pour-in-place and spray foam applications. 

To develop toxicologically safe spray foams, it is necessary to find a curing reaction that does not involve isocyanates but is able to generate rigid foams from low-viscosity prepolymers. These conditions can be met by silane-terminated prepolymers (STPs). 

Foaming Process of Resol-Type Foam. The foaming processes for phenolic foam of both the resol type and benzylic-ether type are the same as those for rigid polyurethane foams. The block-foaming process (slab foaming), pouring process, continuous-laminate process, and spray process are used. See Figure 57. 

Tertiary amines alone can be used as catalysts, but for some applications, such as spraying, more speed is desirable. Metal salts, particularly tin salts, accelerate the foaming reactions, and can be used alone or in combination with the tertiary amine-type catalysts. Tin catalysts of importance for rigid urethane foams are stannous octoate and dibutyltin dilaurate. Stannous octoate will hydrolyze rapidly in the presence of a basic catalyst with loss of activity. Masterbatches containing stannous octoate and moisture are stable for only a few hours at room temperature. Resin masterbatches containing dibutyltin dilaurate may stay stable for months. For this reason this catalyst is preferred for foaming systems packaged for use at other locations or plants where the resin masterbatch is not used immediately (20). 

Bowman, R.A., "Rigid Polyurethane Spray Foam Technology", Technical Papers, Vol. X, 20th Annual Technical Conference, Society of Plastics Engineers, Atlantic City, New Jersey, January 27-30, (1964), Section XXVI, pp. 1-4. 

AX-109 Large-Scale Corner Wall Tests of Spray-On Coatings Over Rigid Polyurethane Foam Insulation (U103). 

Polyether polyols for rigid PU foams are obtained in the same type of polymerisation reactors as those used for high molecular weight polyether polyols, i.e., in stainless steel loop reactors, with an external heat exchanger, preferably with the possibility of generating a large surface of the liquid reaction mass, by a spray technique or by an ejector technique... 

The resulting mixtures of aminic polyols (4.10) are excellent crosslinkers for rigid PU foams and other PU products. The aminic polyols, due to their intrinsic high reactivity are used especially in rigid spray PU foams. 

The resulting polyol, alone or in combination with classic rigid polyols, polyethers or polyesters, has a good potential use in fabricating rigid PU foams, especially in very reactive systems ( spray foams). 

Ryurrm. [Tosoh] Ediylene-vinyl chloride, PVC or blends, or EVAAPVC polymers for rigid and foamed jxo-files, flexible tu film, sheet, shoes and boots, crash pads, inj. molding, wire and cable insulation, pipe, dip and spray coatings, castings. 

Sprayed-on rigid urethane foam can provide more than energy savings to hot oil tanks. The cost of steam can more than justify this type of insulation, but the added benefits are better temperature control of the oil which improves its handling and... 

Chem. Descrip. Tetrabromophthalatediol CAS 20566-35-2 EINECS/ELINCS 243-885-0 Uses Flame retardant for rigid urethane and urethane-modified isocyanurate foams for UL and factory mutual class 1 and 2 specs, slab stock, pour-in-place, and spray foams, urethane coatings and elastomers... 

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