Laminate sheet

Early phenoHc resins consisted of self-curing, resole-type products made with excess formaldehyde, and novolaks, which are thermoplastic in nature and require a hardener. The early products produced by General BakeHte were used in molded parts, insulating varnishes, laminated sheets, and industrial coatings. These areas stiH remain important appHcations, but have been joined by numerous others such as wood bonding, fiber bonding, and plywood adhesives. The number of producers in the 1990s is approximately 20 in the United States and over 60 worldwide. 

Plastic laminated sheets produced in 1913 led to the formation of the Formica Products Company and the commercial introduction, in 1931, of decorative laminates consisting of a urea—formaldehyde surface on an unrefined (kraft) paper core impregnated with phenoHc resin and compressed and heated between poHshed steel platens (8,10). The decorative surface laminates are usually about 1.6 mm thick and bonded to wood (a natural composite), plywood (another laminate), or particle board (a particulate composite). Since 1937, the surface layer of most decorative laminates has been fabricated with melamine—formaldehyde, which can be prepared with mineral fiUers, thus offering improved heat and moisture resistance and allowing a wide range of decorative effects (10,11). 

These effects have been found by Creton et al. [79] who laminated sheets of incompatible polymers, PMMA and PPO, and studied the adhesion using a double cantilever beam test to evaluate fracture toughness Fc. For the original laminate Fc was only 2 J/m, but when interface reinforced with increasing amounts of a symmetrical P.M.M.A.-P.S. diblock copolymer of high degree of polymerisation (A > A e), the fracture toughness increased to around 170 J/m, and then fell to a steady value of 70 J/m (Fig. 9). 

PVF IS used pnmanly as a weather-resistant and environmentally protective film on the surface of laminated sheets of metal, hardboard, paper, and a variety of nonfluonnated plastics Major uses are m architectural siding aircraft cabin interior panels duct lining and pipe covering... 

Material Family Injection Compression Hansfer Casting Cold Molding Coating Structural Foam Extrusion Laminating Sheet Forming RP Molding FRP Filament Dip and Slush Blow Rotational... 

Laminated sheets made from PVC bonded to chlorotrifluoroethylene (CTFE) have the lowest water-vapor permeability of all the materials used in blister packaging. Compared to 250 pm PVC sheet, a lamination of 200 pm PVC-19 pm CTFE (8 mL PVC-0.8 mL CTFE) has a 15-fold lower water-vapor permeability. There are many grades of CTFE available with more or less barrier and ease of formability. Figure 1 shows the difference between flat sheet and formed blister moisture permeabilities. 

Besides, P.O.38 lends color to decorative inks for laminated sheets. Inks formulated at a pigment concentration of 8% and printed in 20 pm cell melamine sheets equal step 6-7 on the Blue Scale for lightfastness at 40 pm, they match step 7. Laminated sheets do not exhibit plate-out. 

For making imbreak-able cups and laminated sheets. 

There are a number of well-established systems for the aseptic packaging of liquids. Notable among these are those packs constructed, box form, in situ on the filling line from a cardboard, aluminium, plastic laminate sheet, such as TetraPak or Combi-box. In the TetraPak system, the packing material enters the filling machine from a feed roll the sheet contact surface is sterilised with warm hydrogen peroxide solution it is formed into a tube, and its lower end is heat-sealed across the width the tube is filled, sealed at the upper end, cut and then folded into a box shape. This produces a continuous output of filled cartons with premium utilisation of bulk storage capacity. 

When describing in more detail the characteristics and methods of manufacture of laminated sheet materials of different types it is helpful to use the classifications below, each of which is covered by a British Standard High-pressure laminates Decorative continuous laminates Direct-faced boards Composite boards. 

Rigid insulation board (includes wallboard and softboard) 0.15-0.40 9.5-25.0 Heat and sound insulation as sheathing, interior paneling, base for plaster or siding, thick laminated sheets for structural decking, cores for doors and partitions, acoustical ceilings... 

The most successful method to provide an unplasticized PVC face to the corrosives was found to be a laminate, calendering a plasticized sheet to the underside (or back side) of the unplasticized sheet to provide a good surface for bonding to the substrate, leaving the rigid side exposed to the harsh chemicals. For many years, this laminate sheet was manufactured in Trenton, NJ, and readily available. Domestic manufacture was discontinued a decade ago, but currently, the material is available on import from Europe, and is stocked in northern New Jersey. 

Polypropylene laminate sheet chemical resistance tables are available from the Gates Rubber Company, Denver, CO. 

TM for high-pressure laminated sheets of melamine and phenolic plastics for decorative applications such as surfacing, adhesives for bonding laminated plastic to other surfaces. 

Fig. 7 Materials flow relationship. (A) Relationship of component section-process-structure-product-performance. (B) schematic of a flat laminate sheet production process. (From Ref. °l)...

There are also a number of technical and trade organizations in this country which have prepared and issued specifications dealing with specialized aspects of the plastics field. The Laminated Products Section of the National Electrical Manufacturers Association has official specifications for laminated sheets, rods, and tubes 20) and for decorative laminated materials 19). The Aeronautical Material Specifications Group of the Society of Automotive Engineers has written specifications for plastic materials to be used in aircraft construction 22). The Society of the Plasties Industry through its Engineer-... 

To extremely fine sugar, such as powdered sugar, starch and/or calcium phosphate in the amount of 1 to 3% is added to prevent the sugar from caking. In addition, powdered sugar is packaged in paper bags or cartons with a moisture-vapor barrier incorporated in the container. This may be either a waxed paper or an asphalted laminated sheet. 

BS 5102, Phenolic Resin Bonded Paper Laminated Sheets for Electrical Applications f London (1974). 

Various forms of chitin-based products are available for medical applications, such as finely divided powder, nonwoven fabrics, porous beads, lyophilized soft fleeces or gels, gauges, laminated sheets, and transparent films. Water-soluble derivatives of chitin in isotonic saline can be administered intramuscularly or intravenously. Certainly, there is considerable biochemical evidence linking NAG with the metabolism of the hexamines, which are assumed to originate and cross-link wound collagen. 

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