Vinylester-based composites

Applications of vinylester-based composites in civil engineering... 

It then reviews the chemistry of vinylester resins together with their mechanical and chemical properties as well as the applications of vinylester resin and composites in the construction industry. The chapter includes indications on future applications of vinylester-based fibre-reinforced composites along with a section devoted to sources of further and relevant information. 

Pultrusion is mainly used to process glass-, aramide-, carbon fiber rovings with a wide variety of thermoset matrices such as polyester-, vinylester- and epoxy-resins [10]. The processing speed can be up to 5 m/min. In addition, thermoplastic matrix based composite pultrusion has been developed over the last 20 years. Due to the higher viscosity of thermoplastics in compaxison to thermosets, the processing speed is about ten times slower in terms of thermoplastic pultrusion [11]. 

Gryshchuk O, Karger-Kocsis J, Thomann R, K6nya Z and Kiricsi I (2006) Multiwall carbon nanotube modified vinylester and vinylester-based hybrid resins. Composites Part A 37 1252-1259. 

Addition poly(imide) oligomers are used as matrix resins for high performance composites based on glass-, carbon- and aramide fibers. The world wide market for advanced composites and adhesives was about 70 million in 1990. This amounted to approximately 30-40 million in resin sales. Currently, epoxy resins constitute over 90% of the matrix resin materials in advanced composites. The remaining 10% are unsaturated polyester and vinylester for the low temperature applications and cyanate esters and addition poly(imides) for high temperatures. More recently thermoplastics have become important and materials such as polyimides and poly(arylene ether) are becoming more competitive with addition polyimides. 

It is of note that the respective amounts of char and flammable volatiles produced by the thermal decomposition of the composite are highly dependent on the chemical nature of the organic phases, i.e., the polymer matrix and synthetic fibres, if present (Levchnick and Wilkie, 2000 Mouritz, 2007). As regards the main thermosetting polymers used in construction (i.e., polyesters, vinylesters and epoxies), pyrolysis yields a large amount of volatiles but retains a small amount of char (10-20% of the initial mass). FRP composites based on these thermoset matrices are thus highly flammable materials. 

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