Types Of Plastic (GRP, FRC, Coloured Plastics)
Glass Reinforced Plastic (GRP):
It is Glass-Reinforced
Plastic and popular with a name of 'GRP'. GRP was developed in the UK during
the second world war as a replacement for the molded plywood used in aircraft.
Glass-reinforced plastic (GRP)
is a composite material or fiber-reinforced plastic made of a plastic
reinforced by fine glass fibers. Like carbon reinforced plastic, the composite
material is commonly referred to by the name of its reinforcing fibers.
Chemosetting plastics like
polyester, vinylester or epoxy are normally used for GRP production. The glass
is or can be in the form of chopped strant mat (CSM) or a woven fabric.
The plastic resins are strong
in compressive loading and relatively weak in tensile strength, whereas the
glass fibers are very strong in tension but weak in compression. By combining
these two materials i.e. plastic resins and glass fibers, it becomes GRP
material which resist both compressive and tensile forces. Hence GRP material
can be used for the structural member subjected to tension and compression.
Uses of GRP:
GRP pipe systems can be used for a variety of
applications, underground as well as above the ground.
(i) Drinking water systems
(ii) Cooling water systems
(iii) Waste water systems
(iv) Sewage systems
(v) Gas systems
(vi) Fire water systems.
2. A wide variety of storage
tanks are made of GRP with capacities upto about 300 tonnes.
3. GRP are also used in the
house building market for the production of roofing laminate, door surrounds,
over-door canopies, window canopies and dormers, chimneys, coping systems,
heads with keystones etc.
4. The use of GRP provides a
much faster installation and because of less height, manual handling issues are
reduced.
5. GRP brick panels can be
used in the construction of composite housing. These panels can be constructed
with the appropriate insulation which reduces heat loss.
6. GRP uses also include hot
tubs, pipes for drinking water and sewers, office plant display containers and
flat roof systems. 7. GRP is also used in the telecommunications industry for
shrouding the visual appearance of antennas.
8. Other uses include sheets
form made electrical insulators and other structural components commonly found
in the power industries.
FRP (Fiber Reinforced Concrete):
It is fiber glass reinforced
plastic and it is termed as FRP in short. It consists of two different materials
which form a composite material having altogether different properties. Many a
times, it is referred as the glass fiber reinforced plastic i.e..GRP.
In case of FRP, the resin
provides a matrix so as to transfer load to the fibers whereas the glass fibers
provide stiffness and tensile strength. The combination of additives, resins
and glass fibers makes the FRP in number of forms having various applications
in the construction field or other field.
Properties of FRP:
It has a good dimensional
stability such that it holds its overall form and shape even under severe
mechanical and environmental stresses all around.
It has corrosion resistant
material.
It has excellent resistance
to moisture and chemicals over a large temperature range. It is durable and has
a long working life.
It is light weight material
and require the less maintenance as it is unaffected by changing weather conditions.
It does not give any bad
effect on health because fiber glass is itself inorganic in nature and
therefore it is one of the safest materials and its products can be used to
store anything. For example, FRP containers are being used to store milk.
It is easy to repair. The
damaged part or portion of FRP can be repaired very easily and quickly and
after repairing it has the same strength as that of the parent body.
It requires very less energy
for its production.
Applications of FRP:
Following
are the some of the applications of FRP in building construction field: The
translucent FRP dome- lights can be used in industrial, commercial and public
building. It is widely used for making domes which creates eye catching aesthetics.
It is used for making roof sheets.
The sheets are available in a many forms with a corrugated type and other. It
eliminates the need for electric lighting inside the shed of industry during
day time and save the electricity.
It is used to make the doors
and window frames. The use of FRP door is more common in bathroom and toilets
because rusting, rotting and swelling can be eliminated. Light weight flush
door and panelled door can be used to the portion subjected to water and
moisture.
Flat, corrugated or fancy FRP sheets are used for
partitions of industrial and commercial buildings. The various fancy designs
and articles made from FRP can be used for wall panelling and ceilings which
are more attractive long lasting and trouble free as well.
It is used for concrete shuttering as it gives
the excellent casting of concrete. The modules and various form of FRP give the
cast concrete shape of very high quality.
It is used for making various
structural sections which have better properties in bending and tension. FRP
sections can be machined, bolted, riveted and tapped just as like steel
sections.
It is used for making the
water storage tanks. The water tanks made in FRP are more superior than steel,
concrete or galvanized iron tanks. FRP chairs, tables, benches can mostly be
used in auditoriums, restaurants, garden, waiting rooms, hotels, theatres etc.
Coloured plastic sheets:
Coloured
thin plastic sheets has many advantages in various fields, especially in rainy
seasons. These plastic sheets are used to cover the cast-in situ portion of
concrete work at the time of rain. Coloured plastic sheets are used to make
raincoats.
The products of FRP are:
(i)Concrete shuttering.
(ii) Doors and window frames
(example, syntex frames)
(iii) Water storage tanks
(example tanks available in market in a trade name of syntex tank).
(iv) Internal partitions and
wall paneling.
(v) Temporary shelters.
(vi) Domes
(vii) Roof sheets
All these products are available extensively with different trade names.