Materials - Polymers

The choice of polymer type is critical to it's performance; there a broadly two types of polymer Thermoplastic and Thermosetting
Thermoplastic molecules generally polymerise end to end to form long chain molecules which will soften under heat. Hence the name thermoplastic. They are usually poor in their resistance to short wave radio wave radiation and will gradually degrade under prolonged UV radiation. Examples of Thermoplastics are Polyethylene, Polystyrene, Polypropylene, PVC, Saturated Polyesters and Nylon.

Thermoset molecules generally polymerise accross the chain (cross linking) and end to end in order to form a 3D molecule which once polymerised cannot be softened or reworked with heat. Once polymerised they are intrinsically resistant to all forms of short wave radiation. Unsaturated polyesters are so good in this respect that they have been specified by BNFL for the encapsulation and disposal of Nuclear waste, when used as a polymer concrete. Examples of Thermosets are Unsaturated Polyesters, Polyurethanes, Phenolics and Epoxies.

Topseal resin is a solution of unsaturated polyester resin in Styrene where both the Styrene and the Polyester cross link together as they cure, to form a 3D polymer of Polyester & Styrene whose properties may be tailored to optimise them for any application where weather resistance and a superb finished appearance are required.