Thermosetting composition

The rigidi d thermoplastic sheet - Tiocess combines thermoplastic sheet vacuum forming with a spray-up or cold press molding process to add a thermoset composite stmctural backing to a decorative thermoplastic skin. Large parts such as bathtubs, hot tubs, recreation vehicle components, and camper tops have been produced by this process. 

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. 

Thermosetting compositions based on urea-formaldehyde are widely employed because of their low cost, wide colour range, rigidity and good electrical properties. 

Because most thermoset composites cure by a thermally activated reaction, a complicated heat transfer process occurs during solidification, the result of an exothermic cross linking reaction in the resin. The complications of thermoset resin curing are compounded by the competing mechanisms of... 

London, BPF, 1994, p.59-64. 627 STRATEGIES FOR RECYCLING AND ENERGY RECOVERY FROM THERMOSET COMPOSITES... 

There are a number of routes for recovering and reeyeling of materials from thermoset composites. With the exception of the ERCOM project none of these are particularly well developed. The most promising for development are innovative comminution techniques for the preparation of relatively uncontaminated forms of scrap as a reinforcement for development of high value... 

Recycling of glass fibre-reinforced plastics is reviewed, with special emphasis on remelting of thermoplastic composites, mechanical recycling of thermoset composites, depolymerisation and dissolution of thermosets and thermoplastics, closed loop recycling of glass, and the use of glass as a mechanical compatibiliser. 32 refs. 

The updated situation of Recycling Thermoset Composites in Japan is diseussed. The dismantling or cutting up of ships, baths, water tanks, and automotive parts are eovered. Recyeling methods include pyrolysis and incineration. Details are also given of uses for recycled materials such as automotive parts, building materials and cement additives. 18 refs. 

Oils, greases, to hard thermoset composition, depending on M.W. and proportion of trifunctional unit2i... 

Processing requirements for thermoset composites, with specific examples of silicones, were recently reported.514 Composites based on the low molecular weight polysiloxanes for medical applications have been reviewed (in Russian).515 Silicone rubber/hydrogel composites have been evaluated for medical applications.516... 

Another important parameter is the choice between thermoplastic and thermoset composites, which are competing for multiple applications. Apart from their characteristic properties, the two families of plastics differ by general features such as ... 

The processing methods will be selected according to the importance of the series, part sizes and targeted properties. Table 6.1 suggests some processes, for thermoplastic and thermoset composites, according to the part sizes and production outputs. 

The parts have good mechanical properties but the creep behaviour is not as good as for thermoset composites. 

The other difference [21] is fhaf fhermosef composife shows higher balanced sfrength and toughness compared to thermoplastic composite, with a little brittleness. Thus, thermoset composite plates can be fabricated relatively thinner and have more applications. On the other hand, as mentioned before, a well developed injection molding process has been applied as the fabrication process of thermoplastic-based composite plates to assure high quality and low cost. 

Cole reviews the nse of Raman spectroscopy to monitor the curing of different thermoset composite polymer systems, thongh he cautions that it is not suitable for certain materials [215]. Cruz et al. studied the effect of elevated pressure on the cure rate and the degree of cnre of unsaturated polyester and other thermoset materials [216,217]. The approach worked well, though the experimental set up required addi-... 

Metal phosphinates have found applications as coatings and lubricants [76], as flame retardant additives in thermosetting compositions [77], and as pigments [78]. The possibility to introduce specific properties by the organic groups has not been exploited yet. 

Crasto. A.S. and Kim, R.Y. (1993). On the determination of residual stresses in fiber-reinforced thermoset composites. J. Reinforced Plast. Composites. 12, 545-558. 

The predominant advantage of pultrusion as a manufacturing method for thermoset composites is the low production cost, which is closely related to the reasonably high... 

The manufacture of polymeric materials, reinforced or unreinforced, is not a single process rather, it is a sequence of processes. For example, the making of a thermoset composite in an... 

Thermosetting composites are cured at either ambient or elevated temperatures to obtain a hard solid by cross-linking. The use of radiation cross-linking decreases the cure time considerably. In particular, an electron beam has been used successfully in many instances. Eor example, glass-fiber-reinforced composites cured by electron beam have been used for the production of cladding panels. ... 

Title Polyester Oligomers, Methods of Making, and Thermosetting Compositions Formed Therefrom... 

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