Rigid foams continuous lamination

Due to the low cost, the excellent physico-mechanical properties of the resulting urethane - isocyanuric foams, thermal and fire resistance and low level of smoke generation, the most important applications of aromatic polyester polyols are for rigid PU/PIR foams in the boardstock market (continuous rigid foam lamination) and for building insulation. 

Hanak et al (9) presented a paper regarding the use of propoxylated Mannich adducts for the production of continuous laminates and fiberglass-reinforced molded rigid foam characterized by CFC reduction or elimination. Table 46 shows an example of the formulation and process conditions employed (9). 

Suprasec VM85 HF Suprasec VM90 HF 2-8-3-1 High functionality polymeric MDI. Rigid polyurethane and isocyanurate foams. Continuous lamination of rigid foam and rigid foam slabstock. 

Rigid foams can be processed as continuous panels or by lamination between two surfacing materials (sandwich panels with a rigid polyurethane foam core). Composite sandwich panels may have particleboard or plasterboard on one surface and cement on the other. Foams can also be produced to fill cavities between metal sheets or sheets of reinforced plastics or in combination on either side. These structures are used as thermal insulation for refrigerator and freezer cabinets, refrigerated transportation vehicles, water heaters, pipes, pipe shells, tanks for gas storage or transport of liquified natural gas, and so on. 

The evolution of rigid foam technology has seen a change from TDI based foams, frequently made by a prepolymer method, to MDI based foams which can be manufactured in slabstock or moulded form, in continuous laminates (sandwich structure), or can be foamed Hn-situ without the hazards of toxicity associated with TDI. Urethane foams can also be sprayed, but positive air pressure hoods should be worn by operatives. 

Uses Foam stabilizer PU rigid foams for continuously laminated PU boardstock, refrigeration and pipe insulation, rigid block foams cell-regulating effect influences dimensional stability and heat conductivity Properties Dens. 1.04 0.1 g/cc vise. 800 150 mPa S solid, pt. < -25 C cloud pt. 

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. 

In building applications rigid polyurethane foam is used laminated to board stock (or to other substrates such as foil or paper), discontinuous or continuous sandwich panels, slabstock, spray, and as pipe insulation material. Some of these sandwich structures are used in building (and transportation) applications that do not exploit their insulation characteristics. The largest volume building application is in roofing insulation [where both PUR and polyisocyanurate (PIR) foams are used]. 

Chem. Descrip. Polysiloxane-polyether copolymer surfactant Uses Foam stabilizer for mfg. of rigid PU foams, continuously laminated PU board-stock, pour-in-place foams, rigid block foams Properties Cl. vise, liq. dens. 1.055 0.01 g/cc vise. 450 120 mPa-s solid, pt. < -15 C hyd. no. 120 12 cloud pt. 64 3C (4% aq.) pH 6.5 1.5 (4% aq.)... 

Uses Foam stabilizer for mfg. of rigid PU foams, continuous laminated PU board-stock, pour-in-place applies. 

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