Glass fibre reinforced polyester composites

A test room of 3 m x 5 m with an internal height of 2.8 m was furnished with vertical PVC, polyethylene, and glass fibre-reinforced polyester pipes of 25 to 90 mm dia., empty or water-filled. Some of them were covered with black-plaster wall. In a second experiment, pipes were mounted horizontally on the walls or under the ceiling. Exhaust conduits of 150 mm dia. were also incorporated, either of glass-fibre-reinforced polyester or PVC/glass-fibre-reinforced polyester composite. Pipes on the wall and the exhaust conduits were loaded with water and air streams, respectively, while the pipes under the ceiling were empty. 

Apart from any damage, all the pipes retained their shape while water was flowing inside. After the fifth ignition, however, when water flow was prevented by the damage, the pipes were destroyed. PVC/glass-fibre-reinforced polyester composite... 

Blaga A. Glass fibre-reinforced polyester composites. Can Build Digest-205. National Research Council of Canada, IRC. 1979. 

Similar models were constructed for glass-fibre reinforced polyester composites, which were degraded for 20 years at 40°C and 60 C. By PCA it was not possible to find a pattern relating the degradation products identified by head-space-GC-MS with temperature and degradation time. By partial least square (PLS) it was instead revealed that two different degradation mechanisms were operating at the two temperatures [35]. 

R S Yamasaki, Surface weatherabihty of glass fibre reinforced polyester sheeting. I - Effect of modification of resin chemical composition . Compos Technol Rev, 1982 4(3) 84-87. 

D Short, A W Stankus and J Summerscales, Woven glass-fibre reinforced polyester resin composites exposed to the marine environment . Proceedings 1st International Conference Testing, Evaluation and Quality Control of Composites, Guildford, September 1983. Butterworth Scientific, Guildford, 1983,... 

Akil, H.M., Santulli, C., Sarasini, E, Tirillo, J., and Valente, T. (2014) Environmental effects on the mechanical behaviour of pultruded jute/glass fibre-reinforced polyester hybrid composites. Compos. ScL Technol., 94, 62—70. 

Stevanovic MM, Stecenko TB, Mechanical-behavior of carbon and glass hybrid fibre reinforced polyester composites, J Mater Sci, 27(4), 941-946, 1992. 

Agarwal et al. [35] analysed the variation of thermal conductivity and thermal diffusivity of banana fibre-reinforced polyester composites caused by the addition of glass fibre. They observed that the thermal conductivity of composites increased when compared with the matrix. However, the thermal conductivity of the composites with increased percentage of glass fibre decreases in comparison to composite of pure banana fibre. 

Cunliffe A M, Williams PT (2003) Characteristion of products from the recycling of glass fibre reinforced polyester waste by pyrolysis . Fuel, 83, 2223-2230. Lopez F A, Martin M I, Alguacil F J, Rincon J M, Centeno T A, Romero M (2012) Thermolysis of fibreglass polyester composite and reutilisation of the glass fibre residue to obtain a glass-ceramic material , J Anal Appl Pyrolysis, 93, 104—112. 

The effect of water absorption on the viscoelastic properties of glass fibre reinforced polyester and polyvinyl ester composites has been investigated using DMA by Fraga et al [ 481. These workers contrasted the water absorption behaviour of the pure, unfilled polymers with composites at two temperatures (40°C and 80°C) and evaluated the relative degree of hydrothermal degradation that occurred. 

A pyrolysis technique was investigated as a method for the chemical recycling of glass fibre-reinforced unsaturated polyester SMC composites. The proeess yielded liquid products and gases and also a solid residue formed in the pyrolysis of glass fibres and fillers. The solid residue was used as a reinforeement/filler in unsaturated polyester BMC composites, and the influenee on mechanical properties was studied in comparison with BMC prepared entirely from virgin materials. 

Kandola, B. K., Akonda, M. H., and Horrocks, A. R. Use of high-performance fibres and intumescents as char promoters in glass-reinforced polyester composites, Polym. Degrad. Stabil. 2005, 88, 123-129. 

By incorporating unsaturated dicarboxylic acids (e.g. maleic acid), besides phthalic acid, into the polycondensation reaction, unsaturated polyesters are formed. These are then cross-linked with a low-molecular unsaturated monomer, usually styrene, in the presence of a peroxide catalyst and a cobalt compound as accelerator. Unsaturated polyesters are applied as cast resins or glass fibre-reinforced composites. The latter product was the first large-scale plastic material in the self-extinguishing category for the building industry... 

Contact moulding is a simple and well known method for fabrication of fibre-reinforced thermoset composites. Thermoset resins which cure at room temperature such as unsaturated polyester, vinyl ester, and epoxy are used to make glass, jute or carbon fibre-reinforced composites using contact moulding. A wide variety of structures can be fabricated using this technique without limitation with respect to the size and complexity of the shape of the structure. However, the process is very labour-intensive and time-consuming, so is used only for a short run or one-off production. 

Krigbaum [12] has reported on the use of glass fibre reinforced composites, both from Cytec Industries, based on Cyglas 685 unsaturated polyester [bulk moulding compound (BMC)] and Cyglas 695 vinyl ester resin (BMC) in automotive valve covers and other engine cover applications. The recycling of these valve covers is also discussed. 

Vinyl ester resins (epoxy diacrylates) are used by the glass-fibre-reinforcement industry for products that are resistant to chemicals and corrosion. They are epoxy di(meth)acrylates (P-hydroxyester acrylates) that are usually obtained by reacting epoxy resins of glycidyl derivatives with (meth)acrylic acid. They can also be manufactured from bisphenol A and glycidyl (meth) acrylates (Kanerva et al. 1986 Kanerva et al. 1989 Jolanki 1991). Acrylates based on bisphenol A or epoxy resin can be polymerised by electron beams, ultraviolet light, and also by the addition of various peroxides (Jolanki et al. 1995). The same cross-linker (styrene), hardeners (organic peroxides) and accelerators (cobalt) as for unsaturated polyester resin are used in composite epoxy acrylates (Rolston 1980). 

New glass fibre-reinforcement products for u.se in fibre-directed preform processes are another focus of development, designed specifically for liquid composite moulding applications such as resin transfer moulding with thermoset polyesters. 

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