Laminating phenolic

Deconvolution technique, 14 237 Decoration, gold, 12 693-694, 703 Decorative cosmetics, 7 860-862 Decorative laminates, phenolic resins in, 18 789-790... 

A continuing trend has been to polymeric retainers. Laminated phenolic cages have often been used for high speeds at temperatures up to 130°C. Heat stabilized nylon-6,6 has come into broad use in small ball bearings, both with and without glass reinforcement (39). Polyimide and PTFE are used up to 250°C. 

Grips maybe made of wood, plastic, laminated phenolic resin, or rubber, and rubber is also used for recoil pads. Customized or ornamental firearms may have grips made from ivory mother of pearl, or buffalo horns, and the firearm may have elaborate engraving some of which is inlaid with gold or silver. Such firearms are unlikely to be used in crime. 

The tremendous growth of the electronics and computer industry has also given a boost to phenolic resin sales. Printed circuits are manufactured by bonding copper foil to a laminated phenolic base, printing the area representing the circuit with acid-resisting ink, and then etching away the remainder of the foil. The dimensional stability, acid resistance, and excellent electricals make phenolics a necessity in the application. 

CAS 21645-51-2 EINECS/ELINCS 244-492-7 Uses Filler, flame retardant, smoke suppressant for spray-up or hand lay-up FRP applies., filament winding, panel prod., resin injection, SMC/ BMC, acrylic sheet rigidizing, cast polyester parts, epoxy encapsulat-ing/potting, powd. coatings, epoxy elec, laminates, phenolic molding, flexible PU foams... 

Fiberglass Reinforced Polymer Laminates Phenolic Resins Polycarbonate Polyethylenes Polyvinyl Chlorides... 

Resorcinol is to phenol as melamine is to urea. Resorcinol—formaldehyde (RF) is very expensive, produces dark and waterproof gluelines, but will cure at room temperature. As with melamine and urea, resorcinol is often combined with phenol to produce phenol—resorcinol—formaldehyde (PRF) adhesives, thus producing an exceUent adhesive with some of the economy of phenol. These adhesives are the mainstay of the laminated timber industry which generally requites a room-temperature cure with durable, waterproof gluelines. 

Property AS TM test CeUul ose acetat b e Phenol. c 1C Extmded plank Expanded plank Extmded sheet PVC Polyether Bu g n Lamin ate... 

Phenol—formaldehyde resins are used as mol ding compounds (see Phenolic resins). Their thermal and electrical properties allow use in electrical, automotive, and kitchen parts. Other uses for phenol—formaldehyde resins include phenoHc foam insulation, foundry mold binders, decorative and industrial laminates, and binders for insulating materials. 

In fires, melamine—phenolic laminates ignite slowly at high temperatures and bum slowly producing smoke that has about the same toxicity as wood smoke (17). 

Laminates. Laminate manufacture involves the impregnation of a web with a Hquid phenoHc resin in a dip-coating operation. Solvent type, resin concentration, and viscosity determine the degree of fiber penetration. The treated web is dried in an oven and the resin cures, sometimes to the B-stage (semicured). Final resin content is between 30 and 70%. The dry sheet is cut and stacked, ready for lamination. In the curing step, multilayers of laminate are stacked or laid up in a press and cured at 150—175°C for several hours. The resins are generally low molecular weight resoles, which have been neutralized with the salt removed. Common carrier solvents for the varnish include acetone, alcohol, and toluene. Alkylated phenols such as cresols improve flexibiUty and moisture resistance in the fused products. 

Particle board and wood chip products have evolved from efforts to make profitable use of the large volumes of sawdust generated aimually. These products are used for floor undedayment and decorative laminates. Most particle board had been produced with urea—formaldehyde adhesive for interior use resin demand per board is high due to the high surface area requiring bonding. Nevertheless, substantial quantities of phenol—formaldehyde-bonded particle board are produced for water-resistant and low formaldehyde appHcations. 

Phenolic Resins. PhenoHc resins [9003-35 ] (qv) are thermosets prepared by the reaction of phenol with formaldehyde, through either the base-cataly2ed one-stage or the acid-cataly2ed two-stage process. The Hquid intermediate may be used as an adhesive and bonding resin for plywood, particle board, ftberboard, insulation, and cores for laminates. The physical properties for typical phenoHc laminates made with wood are Hsted in Table 1. 

The thermal stabiUty of epoxy phenol—novolak resins is useful in adhesives, stmctural and electrical laminates, coatings, castings, and encapsulations for elevated temperature service (Table 3). Filament-wound pipe and storage tanks, liners for pumps and other chemical process equipment, and corrosion-resistant coatings are typical appHcations using the chemically resistant properties of epoxy novolak resins. 

This includes wire enamels on a base of polyvinyl formal, polyurethane or epoxy resins as well as moulding powder plastics on phenol-formaldehyde and similar binders, with cellulose fillers, laminated plastics on paper and cotton cloth base, triacetate cellulose films, films and fibres of polyethylene terephthalate. 

For the lubricated machines, vanes are made of a laminated material impregnated with phenolic resin. For a non-lubricated design, carbon is used. The vane number influences the differential pressure between adjacent vane cells. This influence becomes less as the number of vanes increases. 

NB Daia for the three important ihermosetting materials (phenolics, aminoplastics and epoxide resins) were not covered in the 1998 review on which the 1997 data was based. The 1987 figures for these materials do include a substantial percentage of use in adhesive, surface coating and laminate applications. 

Laminating resins have been offered by Akzo (Diacryl 101), Dow (Derakane Vinyl Esters) and Showa (Spilac). Typical of these is Diacryl 101, which is manufactured by esterification of the addition product of ethylene oxide to bis-phenol A with methacrylic acid. They exhibit lower curing shrinkage than the polyester laminating resins during cure. The structure of Diacryl 101 is... 

There are now commercially available a large range of laminated plastics materials. Resins used include the phenolics, the aminoplastics, polyesters, epoxies, silicones and the furane resins, whilst reinforcements may be of paper, cotton fibre, other organic fibres, asbestos, carbon fibre or glass fibre. Of these the phenolics were the first to achieve commercial significance and they are still of considerable importance. 

The properties of a phenolic laminate will obviously depend on a great many factors. Of these the following are perhaps the most important ... 

From the above comments it will be seen that it is rather difficult to quote typical figures for laminates based on phenolic resins. Thus the figures given in Table 23.3 can be considered only as a general guide. 

Table 23.3 Average physical properties of phenolic resin-based laminates...

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