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C1e) Designer Polymers
Nylon is tough and lightweight. It keeps the
rainwater and ultraviolet light out. It also
keeps the water vapour from the body sweat
in. The sweat condenses and makes wearers
wet and cold inside.
If the nylon is laminated with
PTFE/Polyurethane membrane, clothing can
be made waterproof and breathable. (PTFE is
GORE-TEX® has all the properties of nylon and
it is breathable.
GORE TEX is better because:
Water vapour from sweat can pass through membrane but
The PTFE contains a lot of tiny holes called pores - Too small for water droplets to pass
through (rainwater), but big enough to let water molecules from sweat out. Without the
nylon, the layers would be too fragile to be useful.
Laminated with PTFE/polyurethane membrane.
Inner-layer made from expanded PTFE hydrophobic (water-hating)
Waterproof and breathable
Coping from wetness from sweat and rain
Wind does not pass through membrane Microporus membrane expanded
USE POLYMER OTHER MATERIAL
Contact lens Wet on the eye Dry on the eye
Teeth filling Attractive Looks metallic
Wound dressing Waterproof Gets wet
^Uses of Polymers
Polymers are non-biodegradable not decay or decomposed by bacteria.
Waste Polymers Problem
By landfill sites Landfill sites fill up quickly lasts a long time and wastes valuable land.
By burning/Incineration Burning waste produces toxic gases such as Carbon Dioxide which
adds to global warming. Crude oil used to make polymers is wasted.
By recycling Sorting different polymers makes recycling difficult. Expensive.
Scientists are: Some polymers are water-soluble, which means they dissolve in water, developing
addition polymers that are biodegradable disposed easily when put in landfill sites.
Covalent bonds are stronger within the molecule
Intermolecular forces of attraction between molecules are weak.
Type of Polymer Property 1 Property 2
Weak intermolecular forces of attraction Stretches easily Low melting point
Strong intermolecular chemical bonds or Rigid (pulling force) High-melting