Phenolic adhesives metals

In addition to epoxy-phenolic adhesives three-part epoxy-phenolic-nitrile rubber systems are used in metal-metal edge joints and honeycomb constructions [208], These add toughness not available in most EP systems and improve peel strengths. When used on honeycomb, the NR-P is normally applied to the aluminum skin and the EP to the honeycomb for assembly. Service temperature limitations are those imposed by the NR-P part. 

Though toughened phenolic adhesives remain in use for specific applications, toughened epoxy adhesives have dominated metallic bonding on civil aircraft since their development in the 1960s. Advances since then have been incremental and mostly revolving around manufacturing issues such as handleability and allowed out-time. 

Phenolic/ adhesives adhesives / sealants / gaskets abrasives and break pad binders printed circuit boards structural composites/laminates Metal/glass binders metal oxide binders retroreflective coatings glass optical coatings Hard copy printing inks toners... 

Epoxy-phenolic adhesives were developed primarily for bonding metal joints in high-temperature applications. Their first major application was to join major aircraft components. They are also commonly used for bonding glass, ceramics, and phenolic composites. Because of their relatively good flow properties, epoxy phenolics are also used for bonding honeycomb sandwich composites. 

Phenolic adhesives are structural adhesives with specific applications, e.g. where wide gap bonding is required and where large structures need to be bonded. Phenolic resins are the product of a special reaction ratio of a phenol and formaldehyde in the presence of an organic catalyst. There are two main types of phenolic resins phenol or methylol terminated. The phenol terminated are called novalacs, while the methylol terminated are called resoles (one step resins). Modem phenolic resins are prepared in the presence of metal carboxylates and these resins contain a large number of benzylic ether linkages and have open para positions which have good temperature stability and are usually of low viscosity. 

Phenolic adhesives can contain metal salts of Ca, Mg, Zn, Pb, Cd, Co, Ni and Cu as acetals, halides, hydroxides or sulphonates as activators. These adhesives are limited to room temperature functionality but the use of a specific catalyst such as copper 8-quinolinolate can be used to increase durability at higher temperatures. 

Four laboratory samples of phenolic adhesives were prepared with and without fillers, as shown in Table 6.21, to study methods of sample preparation and analysis for metal content. 

A Practical Approach to Quantitative Metal Analysis of Organic Matrices 6.15.2 Non-Destructive Methods of Analysis of Phenolic Adhesives... 

There are a range of metal catalyst/activators used in phenolic and polyurethane adhesives that can be monitored using ICP-OES. In the metal analysis study of phenolic adhesives, the salts Ca(S03H)2 and Cu(S03H)2 were formulated as listed in Table 6.21, with and without fillers. Several metal salts are employed in polyurethane adhesives for the reasons listed in Table 6.23. As part of the sample preparation study of these products metal salts were formulated into typical polyurethane products consisting of volatile and non-volatile metal salts, listed in Table 6.24, showing the metals of interest and the concentrations expected. 

A special feature of phenolic adhesives is the extremely high heat resistance of the adhesive layers, up to several hundred degrees centigrade. Therefore, they are widely used in car manufacturing for the bonding of brake discs and clutch linings on metal carriers. 

Figure 5.59 Schematic of an RP composite S-2 glass fiber/burn resistant phenolic adhesive prepreg and aluminum metal lay-up (adhesive by Cytee, formerly American Cyanamid, Havre de Grace, MD) includes use on the Airbus A380 fuselage providing directional properties...

Hot-setting phenolic adhesives are processed for up to 15 minutes at 100-150°C and at 0.7-1.7 MPa bonding pressure. The film form is processed for up to 15 minutes at 120-150°C and at 0.7-1.4 MPa. This type of phenolic is resistant to weather, boiling water, and biodeterioration. It has superior temperature stability to that of the acid-catalyzed form. Applications of this adhesive include fabrication of exterior-grade weather- and boil-proof plywood and for bonding glass to metal for electric light bulbs. ... 

Where the adhesive is cross-linked (see Reaction setting adhesives. Epoxide adhesives, Phenolic adhesives single-stage resoles. Phenolic adhesives two-stage novolacs. Rubber-based adhesives and Rubber to metal bonding - basic techniques), it is often... 

They are generally used to bond metals, rubbers, and plastics to themselves or to each other. A major application of vinyl phenolic adhesive is the bonding of copper sheet to plastic laminate in printed circuit board manufacture. 

Neoprene-phenolic adhesives are formulated for room temperature cure and they are used for bonding metal, wood, and many plastics. A combination of neoprene rubber and a / ara-substituted phenolic resin was first described by Thomson. ... 

The sandwich construction method mentioned above involves joining metals to other materials by bonding. Further examples include the bonding of brake linings (phenolic adhesives) and compound materials in ski manufacture, where aluminum is bonded to plastics, wood, etc. (phenolic and epoxy adhesives). Highly alloyed steels, beryllium and titanium alloys, and other special metals can be bonded with adhesives (e.g., polyi-mides, polybenzimidazoles) that have comparable high-temperature resistance. 

Cement, vinyl alcohol-acetate Adhesive, solvent type, polyvinyl chloride Adhesive, phenol and resorcinol resin base Adhesive, polyester, thixotropic Compound insulating, high temperature Adhesive, metal identification plate Cement, natural rubber... 

Nitrile- phenolic Solvent solutions, unsupported and supported film Heat and pressure Excellent shear strength good peel strength superior to vinyl and neoprene—phenolics good adhesion Metals, plastics, glass, rubber Med... 

MIL-A-21366 Adhesive Plastic Table Top to Aluminium. MIL-A-22010 Adhesive, Solvent Type Polyvinylchloride. MIL-A-22397 Phenol and Resorcinol Resin Base. MIL-A-22895 Adhesive, Metal Identification Plate. MIL-A-24179 Adhesive, Flexible. 

Various literature references discuss the use of nitrile rubber/phenolic adhesives for the bonding of metals.Tanaka discussed a two part liquid adhesive system based on solutions of nitrile rubber dissolved in methyl methacrylate. Aluminum plates were bonded together with the resulting adhesive. Kubo reported that the adhesive composition of Table 19 was good for bonding steel plates. 

Nitrile rubber/phenolic adhesives are also quite useful in adhering rubber to various met-als, " e.g., in the manufacture of rubber covered metal rollers. Huber reported that a nitrile/phenolic adhesive composition provided excellent bonding of rubber to a magnesium roll (Table 20). Other metal bonding applications with nitrile rubber/phenolic adhesives include laminating aluminum foil to paper and then to wood, bonding abrasives to metal, and bonding polyamide to metal. 

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