Resin, hardener/, composition

The purpose of the study was a) to determine the effect of relative resin/hardener composition and ambient and elevated temperature curing schedules on the glass transition temperature, Tg, and on the degree of cure of the epoxy system, and b) to evaluate the agreement between the calculated degree of cure using the nth-order kinetic equation (1.1) (1, 2, 3) and the measured degree of cure. 

The commercial possibiUties for epoxy resins were first recognized by DeTrey Emres in Switzerland and DeVoe and Raynolds in the United States (1,2). In 1936, DeTrey Emres produced a low melting bisphenol A-based epoxy resin that gave a thermoset composition with phthaUc anhydride. Apphcation of the hardened composition was foreseen in dental products, but initial attempts to market the resin were unsuccessful. The patents were hcensed to CIBA AG of Basel, Switzerland (now CIBA-GEIGY), and in 1946 the first epoxy adhesive was shown at the Swiss Industries Eair and samples of casting resin were offered to the electrical industry. 

The introduction of organotin residues into an epoxide resin is known to improve the dielectric properties and thermal stability of hardened compositions 71). 

Some satisfactory results were also obtained by modification of properties of phenol-formaldehyde resin (PFR) composites with the synthesized diallylsilazanes (scheme 1). Thas, addition of diallylsilazanes (1-3 mass %) to this composition has improved some of essential characteristics of hardened PFR (table 3). It should be noted that other important physical and mechanical properties of the composites have remained safe (table 3). 

Typical transfer molding compositions for encapsulation of electronic devices are mixtures of an epoxy novolac resin, a phenolic resin hardener, a catalyst, large amounts of inorganic filler (e.g., Si02) flame-retardant ingredients, internal lubricants, carbon black, and sometimes other additives such as getters to trap ionic impurities (34,35), corrosion-protection materials, and stress-relief ingredients. 

Characteristics of the obtained modifiers are shown in Table 4.4. The properties of compositions based on various epoxy resins, hardeners, and modifiers are shown in Tables 4.5-4.8. 

Properties of Compositions Based on Various Epoxy Resins, Hardeners, and Modifiers... 

Melamine-formaldehyde resin, etherified acrylated Sucrose benzoate Vinyltriethoxysilane Vinyltrimethoxysilane Vinyltris (2-methoxyethoxy) silane hardener, composites 4,4 -Diaminodiphenyl sulfone hardener, concrete surface Zinc hexafluorosilicate hardener, cosmetics Alkenyl succinic anhydride hardener, decorative coatings o-Tolyl biguanide hardener, elastomers m-Divinylbenzene hardener, emulsions Chromium acetate (ic) hardener, epoxies... 

Tiitu, M., et al. 2005. Aminic epoxy resin hardeners as reactive solvents for conjugated polymers Polyaniline base/epoxy composites for anticorrosion coatings. Polymer 46 (18) 6855. 

TABLE 3 Strength and dielectric properties of hardened compositions on a basis of epoxy-dian resins ED-20 and epoxy-novolac resins UP-643 with active epoxy siliconotganic thinners (compounds I and 11) and without them... 

Long fibres or fabrics have to be positioned correctly within the manufactured component. This can be achieved most easily if the melting point of the matrix material is well below that of the fibres, as in polymer matrix composites. If duromers are used as matrix, the fibres can be laid down in an uncured mixture of resin and hardener. On curing, the resin hardens to form the duromer. 

Inorganic salt derivatives for Portland cement slurries Epoxy resin hardener for composites... 

Modifier for thermoplastics molding blends Epoxy resin hardener for glass fiber composites Inorganic binders Composites with reduced flammability... 

Crosslinked PVA compositions Photoconductive resins Anionic polymeric resist agents Derivative as epoxy resin hardeners Release coatings Photocurable resins Crosslinked, removable glass coatings... 

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