What is GRP?
According to Wikipedia, GRP is “Glass-reinforced plastic”. It is similar in composition to fibreglass, in that it is a composite material made of plastic which is reinforced by fine fibres made of glass. It is also likened to carbon fibre reinforced plastic (CFRP or CRP).
GRP is very versatile and is resistant to both water and corrosion.
It is light weight and has a very good weight to strength ratio. These attributes lend themselves to usage for cars, boats, surfboards, canoes, planes, karts, lorries, water tanks, wind turbine blades, unusually shaped architectural features, roofing products and bullet-proof glass.
Potential Uses of GRP
The potential uses of GRP are extremely vast. But you have to weigh up the amount of time, effort, energy and money required to produce a GRP product compared to the benefits you will receive out of it. This is because the manufacturing of one-off items compared to mass production is very inefficient. However, this is true with most materials.
GRP is often incorrectly confused with regular plastic, but GRP has many advantages over conventional plastic. For example it will not melt, although it will burn in a very similar way to wood (although it can very easily be made fire retardant).
Strength & Agility
GRP has seven times the flexural strength of steel but it is very lightweight in comparison. It also has a tremendous facility to absorb energy. These factors make it an excellent choice of material for construction of racing cars and boats etc.
GRP is so flexible and versatile that it enables a wide range of finishes to be applied to it, which broadens its attractiveness even further.
Due to the inherent properties of GRP (lightweight, durable, reinforced, flexible, waterproof, malleable) it is increasingly being used to construct flat roofs. Not only is it tough, long-lasting and waterproof, it also has many topcoats and finishes available which means a GRP Flat Roof can be made very attractive in comparison to a traditional felt roof.
GRP is composed of glass fibres: very fine strands of glass with a small diameter which are woven to form a flexible fabric and then moulded with the addition of a polyester resin. A catalyst is used to speed up the reaction and the process is repeated. This creates many layers of fibreglass and resin to produce the required result of a very strong and lightweight material. The finished product can be sanded for a smooth finish or painted/finished according to taste.
There are various different patterns of weaves available to use for fibreglass. The chosen pattern goes a long way to determining the strength and weight of the glass reinforced plastic after the resin has been added. The different weave patterns have been developed for different practical applications.
So not all GRP products are created equally! It is an extremely versatile product and its production should be planned in accordance with the desired results.
Although GRP and fibreglass products have been around since the late 1930s, they have really come of age recently due to the technologies now available and the materials are much less expensive relatively speaking than they were back then.