VnPolyester resin (more loosely referred to as ‘laminating resin’ or ‘fibreglass resin’) is a polymer. Simple to use and economical, it is a major component in many industries, from construction to aerospace. Offering incredible physical and chemical properties, it’s also comparatively cheap compared to other resins like epoxies and urethanes, yet it offers similar – if not superior – performance in many cases.
The term ‘polyester resin’ largely refers to ‘unsaturated polyester resin’ unless otherwise specified.
Applications of Polyester Resin
Polyester is primarily used in composite applications where it is typically combined with glass fibre reinforcement to create fibreglass – also known as glass reinforced polyester (GRP).
The mechanical properties of polyester are substantially enhanced when combined with glass fibre. Acting as a low-cost reinforcement phase to polyester’s matrix phase, glass fibre adds mechanical strength to the composite, itself bound together by the resin.
Classic examples of fibreglass linings, coatings and moulds include, but are not limited to storage tanks, pipes, automotive components and marine components (e.g., boat and yacht hulls and decks) as well as fibreglass roof materials and associated fibreglass repair kits. It is also used as an ingredient in speciality coatings and adhesives.
A Leading Polymer
Polymers comprise a large number of units of a few types. These units comprise atoms, which constitute segments of the polymer. The polymerization of two monomers, the structure of each macromolecule contains units of both monomers. Such a polymer is called a copolymer, where its synthesis is called copolymerization.
Polyester resin has been a vital ingredient in the advancement of many industries throughout the 20th century and well into the 21st century. Polyester resins stand globally as one of the most popular thermoset resins. Over 2 million tonnes of unsaturated polyester resins are used for flat roofs, pipes, storage tanks and other waterproofing linings as well as high-specification components for the construction, marine, aerospace and automotive industries.
Polyester resins have high thermal and heat stability, low shrinkage and good mechanical strength when combined with glass fibre to create composite structures.
This article describes the science, applications, properties and market size of the global polyester resin market.
Development of Polyester Resin
Resin has been around for millions of years. Take amber – a common tree resin made famous for its ability to preserve insects and other creatures. Yet the origins of synthetically produced resins like polyester date back to the 1800s, having been one of the first resins developed and ultimately acting as the basis of the plastics industry we know today.
One of the first breakthroughs in polyester production was in 1847 by Berzelius, who developed a reaction between tartaric acid with glycerol to form a polyester resin. Several years later in 1863, Lorenzo reacted ethylene glycol with succinic acid, yielding a second polyester reaction scheme. Later, the unsaturated polyester resin we know today was first developed by Daniel Vorlander in 1894 utilising glycol maleates.
Whilst many incremental improvements have been made to polyester resin, the most commonly used method for production centres on a reaction between diethylene glycol (HO–CH2–CH2–OH) and unsaturated aliphatic acid (e.g. maleic acid, HOOC–CH=CH–COOH).
Unsaturated polyester resin is dissolved in an unsaturated solvent (namely styrene or alpha-methyl styrene).