Page 28 - Science Class 08
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natural polymers. Other fibres are man-made. co on. It’s a low-cost and convenient fibre to
They are polymers, many of which are obtained work with and lends itself to diverse uses.
from petroleum. They are called synthe c There are several grades of rayon that can
fibres. Rayon, nylon and polyester are some imitate the look and texture of other natural
synthe c fibres. fibres such as co on, linen and silk. The
RAYON different types of rayon include viscose, modal
and lyocell.
Silk is a natural fibre with a beau ful texture.
However, it is expensive. A empts at making a Uses of Rayon
synthe c fibre with similar texture succeeded Some major rayon fibre uses are:
towards the end of the nineteenth century, v Apparel : Accessories, jackets, undergar-
when scien sts made rayon. Rayon is also ments, slacks, sports wears, suits, es, etc.
called ar ficial silk. It is cheaper than silk and
v Home furnishings : Bedsheets, curtains,
can be woven like silk fibres.
blankets, draperies, tablecloth, slipcovers,
Rayon is made from wood pulp. Wood pulp is
etc.
first dissolved in an alkaline solu on. The thick
liquid produced is then passed through ny v Industrial uses : Industrial products, medical
surgical products, non-woven products, re
holes to make fibres. The fibres are hardened
cord, etc.
v It is used to make apparel, such as suits,
es, blouses, jackets, stockings, slacks,
sportswear, etc.
v Home furnishings, such as bedspreads,
bedsheets, blankets, curtains, tablecloths,
upholstery, carpets, etc. are made from
rayon fibre, as it has a silky lustre.
Proper es of Rayon
Rayon
While synthesising rayon fibres many pro-
by passing them into a bath of sulphuric acid. per es are added them so as to make them
The fibres are then spun into yarn and woven widely used.
into cloth. v Thermal proper es : Viscose rayon loses
Rayon is called a regenerated fibre because the strength above 149°C; chars and decom-
original raw material, cellulose, is broken down poses at 177 to 204 °C. It does not melt or
and then reformed. This makes it stronger and s ck at elevated temperatures.
easier to dye in a variety of colours. Another v Chemical proper es : Hot dilute acids make
useful property of rayon is that it absorbs any effect on rayon whereas bases do not
sweat. Rayon clothes are therefore comfortable
make any effect on rayon. Rayon gets
to wear in summers.
effected by bleaches at very high concen-
Rayon is a natural-based material that is made tra ons and by milder under severe hot
from the cellulose obtained from wood pulp or
28 Science-8
