Rigid foam sheet

A rigid foam sheet product is made by heating at least one surface of a crosslinked PE foam sheet material to a temp, sufficient to cause a slight surface post-expansion of the sheet material and contacting the heated, post expanded foam surface with a cold metal element to form a product with the desired, accurate thickness or having a desired three-dimensional design on the sheet material. USA... 

Rigid foam sheet. [Data from Noreen, L T, Blowing agents and foaming processes 2006,... 

Polyurethane. SmaU quantities of polyurethane film are produced as a tough mbber-like film. Polyurethane is more commonly used to produce foamed sheet, both flexible and rigid. The flexible foam is used as cushioning in furniture and bedding the rigid foam is widely used for architectural insulation because of its outstanding thermal insulation efficiency (see Urethane POLYMERS). 

The present invention provides a polypropylene-based foamed sheet whose expansion ratio is 4 or more times characterised by expansion ratio A of the part (skin layer) up to 20% in each of the seat thickness from both snrface of said polypropylene-based foamed sheet and expansion ratio B of part other than said skin layer (core layer) satisfying the following formnla (1) 1.3 less than or equal to B/A. The polypropylene-based foamed sheet of the present invention is excellent in the balance of lightweight properties and rigidity. 

Available forms Sheet, plates, rods, rigid foam, expandable beads or spheres. 

CFC-12 has been widely used also for producing rigid plastic foams. The characteristic example is the formation of foam sheets such as those used in white trays of the sort to package fresh meat products and in hamburger clamshell cartons used by fast-food restaurants. 

Simple CS (Caulk and Seal) - A technique for Insulating and sealing exterior walls that reduces vapor diffusion through air leakage points by installing pre-cut blocks of rigid foam insulation over floor joists, sheet subfloor, and top plates before drywall is installed. 

Uses Mfg. of pressure-sensitive adhesives, self-adhesive coatings for textile fabrics, nonwovens, plastic films, paper, sheet metal, glass, rigid foam plastics, etc. 

As a cover, artificial leather and rigid PVC sheet exerted no protection at all. Finished cardboard was unexpectedly poor it blistered straightaway after the first ignition, becoming separated from the foam core, and was then destroyed completely in the course of the succeeding fires. The fibreboard offered reasonable protection only an overspread fire could cause its ignition and deterioration. Sprayed asbestos wool and mortar provided the most satisfactory protection. 

PU are used in various forms, namely foam (flexible or rigid), elastomer sheet, coating,... 

The monoalkyl tin compoimds (R=l) are particularly rapid in their stabilising action, and are favoured in long-life applications such as rigid pipe, as well as certain flexible products. They give optically clear sheeting, including foam sheeting, and are available in both liquid and solid... 

Rigid polystyrene foam is used for the manufacture of composite sheets, for example, for containers and prefabricated building boards. The rigid foam is combined with metals, wood-based materials, asbestos, cement, and plastic sheets. Polyurethane adhesives are particularly effective in this field. 

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. 

One of the most rapidly expanding areas of PVC technology is that of rigid foam products, leading to foam core pipe, siding substrate, sheet, profile, and wood composites (plastic lumber). Comparisons between formulations for solid and foamed products are illustrative °... 

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