frp expertise

Fibre Reinforced Plastic (FRP), also called fibreglass, is a composite material consisting of plastic resin and a fibrous reinforcing material. FRP has a high strength-to-weight ratio and high corrosion resistance. It is stable against solvents and acids, as well as temperature extremes. These combined properties make FRP an outstanding material for fabricating CPPE's gas treatment process vessels and ducts.

The materials mainly used for our projects are Derakane 411-45 and Derakane 470, depending on temperature conditions.

Production

Before processing, these resins are viscous liquids which are dissolved in copolymerisable monomers (stryrene). Glass fibres saturated with unsaturated polyester (UP) or vinyl ester resin are used for the reinforcement.

Before saturating the glass fibres as described – manually or with machines – radicals (peroxides) must be added to the liquid resins in order to initiate a reaction and to convert the resin from a liquid into a cross-linked polymer.

The density and length of glass fibres are chosen for the required mechanical performance. Essential to product quality is that the glass fibres are well saturated with resin.

Processing time is 15 to 45 minutes and can be accelerated or slowed down by the use of accelerators or inhibitors. It is possible to adapt to various climatic conditions, or the necessary reaction time, by individually varying the three components (hardener, accelerator and inhibitor).

Depending on the formula used, an exothermic curing reaction is generated within 80 to 120 minutes, releasing heat. During the curing process the UP or vinyl ester resin is hardened by forming cross-linked products via copolymerisation through styrene radicals.

The vinyl ester resin is designed on a Bisphenol A base in the case of Derakane 411-45 (or Palatal 430). For Derakane 470 (or Palatal 440) a base of Novolac is used.

Disposal

At end-of-life, the FRP is an inert, stable material which can be burned to recover energy or recycled as building or highway material.