Civil Engineering Reference
In-Depth Information
2.1.1.7 Acrylic
Acrylic
fibres extensively used for furnishing fabrics. In
architecture, due to the reduced mechanical performance, they are used for small
deployable tents and umbrellas due to their
fibres are synthetic
flexibility and good resistance to oils,
chemicals, and to deterioration from sunlight exposure. In addition, it can also be
made to mimic other
fl
bres such as cotton.
2.1.1.8 Polyurethane
Elastane, a polyurethane-polyurea copolymer, is exclusively used for indoor
applications which require exceptional elasticity. Highly appreciated for the rela-
tively low price and the reduced risk of wrinkles, this type of fabric is not suitable
for wind and snow loads.
2.1.1.9 Cotton
Pure cotton is characterised by a poor tensile strength, a relatively high elasticity
and a high vulnerability to microbial attack and the consequent biological degra-
dation. For this reason its use is mainly restricted to leisure tents, indoor applica-
tions and projects which do not requires high and durable mechanical performance
(Stegmaier et al.
2010
).
2.1.2 Coatings
The
final properties of a coated fabric, with the only exception of the mechanical
performance, are mainly related to the materials used for the top coatings. They are
usually placed on both sides of the fabric and can be combined with several
additives in order to achieve the requirements in terms of weather and UV resis-
tance, chemical and biological attacks,
fire behaviour and colour stability. There-
fore, the quality of the coating is fundamental for the service life of the material.
The doctor blade (PVC) and the dip coating (PTFE) are the most common coating
methods however, the coatings can be applied to the fabric also by laminating,
rolling or brushing on the basis of the chemical compatibility with the
bres.
2.1.2.1 PVC
Polyvinylchloride (PVC) is generally used in combination with polyester fabrics.
Additional additives and top-coatings are generally used to improve the
re
behaviour,
the expected lifespan,
the self-cleaning properties and the colour
