Synthetic Fibres & Plastics
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Transcript of Synthetic Fibres & Plastics
Synthetic Fibres & Plastics
Synthetic Fibres
Synthetic fibres are the result of
extensive research by scientists to
improve on naturally
occurring animal and plant fibres. In
general, synthetic fibres are created by
forcing, usually through extrusion, fibre
forming materials through holes (called
spinnerets) into the air, forming a thread.
Synthetic Fibres
Nylon(Monomer- Hexamethylene)
Nylon is a generic designation for a
family of synthetic polymers known
generically as polyamides, first
produced on February 28, 1935,
by Wallace Carothers.
Polyester(Monomer- Ester)
Polyester is a category of polymers which
contain the ester functional group in their
main chain. Although there are many
polyesters, the term "polyester" as a specific
material most commonly refers
to polyethylene terephthalate (PET).
Rayon(Monomer-Cellulose)
Rayon is a manufactured
regenerated cellulose fibre. Because it is
produced from naturally
occurring polymers, it is neither a
truly synthetic fibre nor a natural fibre; it is
a semi-synthetic
Acrylic(Monomer- Polyacrylonitrile)
Acrylic fibers are synthetic fibers made
from a polymer (polyacrylonitrile) with
an average molecular weight of
~100,000, about 1900 monomer units
Disadvantages of Synthetics
• Synthetic fibers melt before burning
• Some electrical charge accumulates on the synthetic fibers. The electrical charge causes irritation of the skin.
• Extremely hazardous to the environment.
• Can make you overheat
• Can make you cold when wet
Advantages of Synthetics
• Synthetic fibers do not depend either on an agricultural crop or
on animal farming.
• They are generally cheaper than natural fibre.
• Synthetic fibers possess unique characteristics which make them
popular dress material.
• They dry up quickly, are durable, readily available and easy to
Plastics
Plastics
A plastic material is any of a wide range
of synthetic or semi-
synthetic organic solids that
are mouldable. Plastics are
typically organic polymers of
high molecular mass, but they often
contain other substances. They are
usually synthetic, most commonly
derived from petrochemicals, but many
are partially natural.
Thermoplastics
A Thermoplastic, also known as
a thermosoftening plastic, is
a polymer that becomes pliable or
moldable above a specific temperature,
and returns to a solid state upon cooling
Thermosetting Plastics
A thermosetting plastic, also known as
a thermoset, is polymer material that
irreversibly cures. The cure may be done
through heat (generally above 200
°C (392 °F)), through a chemical reaction
(two-part epoxy, for example),
or irradiation such as electron beam
processing.
Be Alert…Melamine Cancer
If you eat in a Melamine Plate, you may
become a victim of Melamine Cancer.
Melamine is a thermosetting plastic and
is non-biodegradable. While eating
when we scratch the plate with the
spoon, the melamine coating also goes
into our body which may cause Cancer.
Check under your plates whether
Melamine made is written or not. Use
Bone China, Glass or Steel Plates
instead
Plastic….Harm to Environment
Plastics have transformed modern
society, providing attractive benefits
but also befouling waterways and
aquifers, depleting petroleum supplies
and disrupting human health.
The 3 R’s
Reducing the amount of waste you produce
is the best way to help the environment.
Instead of throwing things away, try to find
ways to use them again! Many of the
things we use every day, like paper bags,
soda cans, and milk cartons, are made out
of materials that can be recycled.