Epoxy-based systems

Peroxidic groups in oxidized polyolefins have frequently been employed as sources of free radicals to allow grafting of vinyl monomers to polyolefins (2f[). Some of the products from the gas reactions also have interesting potential as reactive sites. For example, chloroformate groups are well known to react with alcohols, and amines 2J[). Thus chloroformate groups could be useful for example in coupling highly oriented polyolefin fibres to resins such as epoxy based systems. 

Modified epoxies are generally selected for lower-temperature applications. The unmodified epoxy-based systems are not as attractive for low-temperature applications as some... 

Powder adhesives are generally one-part, epoxy-based systems that do not require metering and mixing but often must be refrigerated for an extended shelf life. Elastomeric... 

Transient dynamic mechanical data on the DGEBA-TETA and high performance M-5208 epoxy based systems have been obtained and compared with "equilibrium" data.. The transient data have demonstrated that moisture can act not only to plasticize an epoxy network but also to restrict and stiffen molecular chain movement. The behavior observed was explained by examining the synergistic effects that moisture and temperature have on the particular epoxy network structure. 

Substituting a solid epoxy for the liquid epoxy as shown in Table III (Formulations 5 and 6), extends the pot life out to 6 hours at 60% volume solids. Both the solid and liquid epoxy based systems give excellent coatings with good corrosion resistance. 

CAS 112945-52-5 EINECS/ELINCS 231-545-4 Uses Thickener, thixotrope, structuring agent for epoxy-based systems, adhesive and multilayer systems antisettling agent, antisag agenL corrosion inhibitor for paints, plastics... 

Uses Conductivity agent in epoxy-based systems for conductive coatings for ESD and ESP Properties Off-wh. paste 64.4% NV Toxicology TSCA listed... 

Epoxy-based systems are the most widely used structural adhesives. They are encountered everywhere in car manufacture, aircraft, building and construction industries, metal fabrication and the home. They are available as single-part and two-part. 

Thus, substrates such as aluminium and its alloys, alloys of titanium, low- and high-carbon steels, nickel, copper, fibre-reinforced plastics (containing both thermoplastic and thermosetting matrices - in the latter case, the matrix might well also be a formnlated epoxy-based system), glass, concrete and wood are all encountered. This means that they can be, and indeed are, widely used in construction, aerospace, automotive (both original equipment and aftermarket), electrical and electronics, furnimre, foundry, consumer and abrasives applications. 

In one case (Method I), the organic component forms a phase-separated macro-molecular network, which is chemically bound to the surrounding inorganic domains (e.g., epoxy-based systems). 

A progressive loss of reactivity leading ultimately to a complete failure to cure (unlikely in epoxy-based systems) ... 

The epoxy used in the epoxy-aerylate system and in the epoxy-based system for HDG steel, is a typical DGEBA type epoxy formulated from epichlorohydrin and bisphenol A [11, 61] ... 

Fig. 7. ASTM B-117 salt spray test results of (a) the chromate conlrol on AA 2024-T3 (b) the acrylate-epoxy based system on AA 2024-T3 (c) the novolac epoxy-polyurethane based coating on AA 2024-T3 (d) the polyurethane-based coating on AA 6061 (e) the epoxy-based system on HDG and (f) the chromate control on HDG [30],...

Fig. 9.2 Effect of particle size on the DC breakdown strength of epoxy-based systems containing 10 % of boron nitride. The dashed horizontal line indicates the breakdown strength of the unfilled polymer data from Andritsch (2010)...

Epoxy-polyamide adhesives can be made serviceable at very low temperatures by the addition of appropriate fillers to control thermal expansion. But the epoxy-based systems are not as attractive as some others because of brittleness and corresponding low peel and impact strength at cryogenic temperatures. 

The REZKLAD epoxy-based system consists of a Concrete Primer and Flooring Compound, plus an Expansion Joint Compound and Surface Sealer available for use where necessary. The CLADKOTE Flooring Compound is a modified polyester, resin-based monolithic overlay for concrete. The composite of resins and siliceous reinforcing material cures to a tough, chemical resistant topping. CLADKOTE C utilizes a 100% carbon filler specifically designed for service in hydrofluoric acid and fluoride salts. 

All the results have been expressed as a percentage of the room temperature value. The modulus and strength of the epoxy-based system hold up well up to 150°C, though the interlaminar shear strength begins to decrease immediately the temperature at which the measurements are made increases. The polystyryl pyridine matrix gives the best retention of strength with temperature while the results for the bismaleimides and polyimide-based composites are similar but rather lower. 

High performance, epoxy-based systems are widely and increasingly used in structural aerospace and other applications as both adhesives and the matrix of fibre-reinforced composites. Many studies have been conducted on epoxy systems directed towards elucidating structure-property relationships. This has resulted in a greatly increased level of understanding of these complex systems but has also indicated the complexity of the interrelations between composition, thermal history and properties. 

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