JEC COMPOSITES MAGAZINE - Issue #67 - August/September 2011 - 25

Phenolic resins in fibre-reinforced composites
The year 2010 marked the centennial of the production of phenolic resins by Leo Baekeland. Today, the worldwide sales volume of phenolic resins is close to 6 million metric tons a year. Phenolic resins continue to be a major matrix resin for a variety of materials, with favourable cost/performance characteristics that surpass most other resin systems.
phenol), and perishability of the intermediate resole resin. In spite of these disadvantages, the major contribution of phenolic resins in their use as matrix resin in fibre-reinforced composite systems is the FST characteristics that the phenolic matrix resin provides to the resulting fibre-reinforced composite. These attractive attributes coupled with economic advantages are the motivating factors for the continued use of phenolic resins in FRP components. Thus, the low FST values of phenolic resins have fostered the use of phenolic matrix resins in composite systems for a diversity of performancedriven applications such as aircraft interiors, aircraft cargo liners, interior panels/standbacks for rail rolling stock, offshore oilfield platform gratings and deluge pipe, tunnel materials, and a wide range of fire-resistant components. Resin manufacturers include Momentive, Sumitomo Bakelite, Georgia Pacific, Gun Ei, Asahi, Shandong Shenquan Chemical, Dynea, Plenco, Ashland, and Lewcott. These resins are transformed into resin matrix systems for fibre composite intermediates such as prepregs, SMC, and RTM systems. Phenolic resins provide excellent thermal stability within a temperature range of 150 to 180°C and continue to maintain reasonable mechanical strength/performance beyond this temperature range due to the carbonization of the resin into pseudo carbon-containing composites. It is this unique characteristic that makes phenolic resins quite valuable in critical applications such as fibre-reinforced friction elements, fibre-reinforced rocket nozzle insulation, aircraft interiors, and other related FST composite systems. Phenolic resins are moderatelypolar resin systems with a predominance of phenolic hydroxyls as well as methylol functionality (resoles) within the resin structure. These polar surface effects of phenolic resins contribute to their ubiquitous bonding performance to the diversity of substrates which were mentioned earlier.

resin

DR. LOUIS PILATO PILATO CONSULTING

Introduction
The centennial celebration for the commercialization of phenolic resins by Leo Baekeland took place in 2010. In spite of some seemingly adverse property limitations (especially brittleness),

Phenolic resins for FRP - FST characteristics - 150-180°C use temperature - Chemical and corrosion resistance - Nearly 6 million metric tons/year globally - Favourable cost/performance features

Main features...

henolic resins are critical in many FRP applications where FST (Fire, Smoke, low Toxicity) characteristics and mechanical strength are required. This paper discusses phenolic-based FRP systems, as well as new phenolic resin related systems based on benzoxazines and a novel toughened resin system, polyarylether amide matrix resin, known as Calidur™.

phenolic resins continue as a large commodity resin system with volumes of nearly 6 million metric tons/year worldwide. They are a ubiquitous binder for a variety of substrates ranging from wood, glass, metal, paper, rubber, etc. with favourable cost/performance characteristics that surpass most other polymeric resin systems [1]. Phenolic resins exhibit excellent dimensional stability with a constant use temperature range from 150 to 180ºC and excellent chemical and corrosion resistance. Phenolic resins also possess some limitations such as brittleness, by-product emissions (water, trace amounts of formaldehyde and

No67 August - September 2011 / jec composites magazine

Types of fibre-reinforced phenolic resin composites
Fibre-reinforced phenolic resin composites consist of chopped fibre and woven or long fibrereinforced resin systems. The

JEC COMPOSITES MAGAZINE - Issue #67 - August/September 2011

Table of Contents for the Digital Edition of JEC COMPOSITES MAGAZINE - Issue #67 - August/September 2011