Polyester is a the synthetic fiber that detains the first place in terms of global production. It is a linear polymer whose mass comprises predominantly (at least 80%) of the ester functions and terephthalic acid. The polyester yarn is lightweight and flexible. It is resistant to ultraviolet radiation. Low flammability. It softens at 245 ° C and melts at 250 ° C. It keeps a good shape memory and can therefore be used into coated fabrics composition. Furthermore, a suitable weaving also allows good heat dissipation.
Butyl, also known as Isobutylene-isoprene (IIR), is a synthetic rubber developed in the 1940’s. It has exceptionally low gas permeability making it ideal for inner tubes and high pressure/vacuum sealing applications. Its very low resilience makes it suitable for shock and vibration damping. Its chemical unsaturation gives it excellent resistance to heat, ozone, and weathering, and also to dilute acids and alkalis.
It is not suitable for use in mineral or petroleum based fluids.