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Artificial and natural polymers: plastics, fibres, ceramics, rubbers
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POLYMERSBy:
Asmita-1404Palak-528
Anjali-1368Tanya-1149Deepika-169
WHAT ARE POLYMERS?
A substance which has a molecular structure built up chiefly or completely from a large
number of similar units bonded together, e.g. many synthetic organic materials used as
plastics and resins.
TYPES
NATURAL ARTIFICIAL
NATURAL POLYMERS
• These are polymers which we derive from nature. Eg: proteins and fibres, such as hair, nails, tortoise shell, cellulose in paper and tree, DNA
ARTIFICIAL POLYMERS
These are chemically made by man. Eg. Plastics, ceramics
PLASTICS
WHAT IS PLASTIC??
• PLASTIC is an organic polymer with the ability to flow into desired shape when heat and pressure are applied to it and retain the shape when they are withdrawn.
• They are usually synthetic, most commonly derived from petrochemicals, but many are partially natural.
All Plastics fall within two groups
Thermoplastics Thermosettings
THERMOPLASTICSTHERMOPLASTICS are those that can be
melted many times
Types •cellul
ose acetate
• etil cellulose
CELLULOSICS THERMOPLASTICS:·
•· polyethylene · pvc
•polymethyl methacrylate
•polystyrene
•polypropylene · polyamides
PETROLEUM THEMOPLASTICS
EXAMPLES
THERMOSETTINGSTHERMOSETTINGS are the ones that only can be melted once. ·
Types
MELAMINE is used, for
example, to cover sheets of
wood.
POLYESTERS. The majority of the clothes have, at
least, a little percentage of
polyester .
EXAMPLES
PLASTICS PROPERTIES •it
means that other materials like iron can't deformate so easy as plastic because plastic has more flexibility than iron
DEFORMING CAPACITY
•it means that it weighs less than other materials for example, plastic is lighter than the iron or steel (Low Density
LIGHTNESS
• it means that it does not break easily if it falls down to the floor or crash with something, like other materials, for example glass
MECANIC RESISTANCE
Environmental Pollution: The
Harmful Effects of Plastics …….
The toxic smoke produced while burning plastic kills thousands each year. Workers and people living near a plastic or resin factory are prone to LUNGS & INTESTINAL cancer and birth defects.
Plastic bags kill animals. About 100,000 animals such as dolphins, turtles whales, penguins are killed every year due to plastic bags. Many animals ingest plastic bags, mistaking
them for food, and therefore die.
The land gets littered by plastic bag garbage presenting an ugly and unhygienic seen. Plastic waste blocks drains and gutters, stopping the flow of rain water and sewerage
PLASTIC POLLUTION
WHAT CAN WE DO TO STOP THIS??
USE PAPER BAGS
DISPOSE PLASTIC PROPERLY
Not using plastic bags will help the
planet
RUBBER AND TYRESA tire (or tyre) is a ring-shaped covering that fits
around a wheel's rim to protect it and enable better vehicle performance.
The materials of modern pneumatic tires are synthetic rubber, natural rubber, fabric and wire,
along with carbon black and other chemical compounds. Pneumatic tires are used on many types
of vehicles, including cars, bicycles, motorcycles, trucks, earthmovers, and aircraft.
HISTORY
• The development of this technology hinges on myriad engineering advances. In terms of materials, the vulcanization of natural rubber is credited to Charles Goodyear and Robert William Thomson. Synthetic rubbers were invented in the laboratories of Bayer in the 1920s. Today, over 1 billion tires are produced annually in over 400 tire factories.
MANUFACTURING• Pneumatic tires are manufactured in about 450 tire
factories around the world. • Over one billion tires are manufactured annually,
making the tire industry a major consumer of natural rubber.
• In 2004, $80 billion of tires were sold worldwide in 2010 it was $140 billion.
• The top five tire manufacturing companies by revenue are Bridgestone Michelin, Goodyear, Continental and Pirelli.
COMPONENTS• Tread-The tread is the part of the tire that comes in contact
with the road surface. The tread pattern is characterized by the geometrical shape of the grooves, lugs, voids and sipes.
• Tread lug -Tread lugs provide the contact surface necessary to provide traction. As it rotates through the footprint it is deformed circumferentially.
• Tread void -Tread voids provide space for the lug to flex and deform as it enters and exits the footprint. Voids also provide channels for rainwater, mud, and snow to be channeled away from the footprint.
• Sidewall -The sidewall is that part of the tire that bridges between the tread and bead.
• Shoulder - The shoulder is that part of the tire at the edge of the tread as it makes transition to the sidewall.
• Bead - The bead is that part of the tire that contacts the rim on the wheel.
• Rain groove - The rain groove is a design element of the tread pattern specifically arranged to channel water away from the footprint.
• Sipe - Tread lugs often feature small narrow voids, or sipes, that improve the flexibility of the lug to deform as it traverses the footprint area.
Fibre FactsTextiles
Fibres
• Fibres are the base unit of all textile materials and products.
• They are slender thread-like structures that can be spun into yarns and thread, and woven, knitted or felted into materials.
Magnified Merino
Wool Fibres
Fibre Classifications
• There are two types of fibres used in making textile products – those that come from the natural environment and those that are manufactured by humans, called man-made fibres.
VS
Natural Fibre Classifications: which come from plants, animals and minerals.
Natural Fibres
Cellulose
CottonLinenFlax Hemp
Protein
Wool Silk AngoraAlpacaMohair
Plant Fibres – Cellulose Fibres
• Cotton
• Linen/Flax
• Hemp
Animal Fibres – Protein Fibres
• Silk
• Wool
• Alpaca
• Angora
Man-Made Fibre Classifications: made usually from chemical sources.
Man-made Fibres
Regenerated
Rayon Acetate Polyester
Synthetic
Nylon Acrylic Lycra
Man-made – Synthetic Fibres
• Nylon
• Polyester
• Acrylic
• Lycra (Elastomeric)
These fibres primarily come from oil and coal.
Man-made – Regenerated Fibres
• Rayon
• Acetate
These fibres primarily come from wood pulp.
USES• Clothing• Carpets• Curtains• Towels• Furnishings• Upholstery
• Automotive applications
• Medical textiles• Geotextiles• Agrotextiles• Protective
clothing
CERAMICSThe word “CERAMIC” comes
from the GREEK word {keramikos} “OF POTTERY”
or “FOR POTTERY”{keramos}.
WHAT IS A CERAMIC ?
• CERAMICS are inorganic , non-metallic solid prepared by the action of heat and subsequent cooling.
• CERAMIC material may have a crystalline or partly crystalline structure, or may be amorphous [e.g. A glass].
• CERAMIC material are brittle , hard and strong. They can withstand chemical erosion and high temperature.
TYPES OF CERAMIC PRODUCTS
• Structural ceramics including bricks ,pipes, floor and roof tiles.
• Refractories such as kiln linings ,gas fire radiants ,steel and glass making crucibles.
• Whitewares ,including tableware ,cookware ,wall tiles ,pottery products and sanitary ware.
• Engineering ceramics used in biomedical implants [ceramic capping used after root canal treatment of teeth ] ,disk brakes.
WHITEWARE• Whiteware are ceramic products whose colour
varies from white to off white.• Glass is one of the main components of
whiteware. Egs of whiteware include dinnerware made of fine china , wash basins , dental implants and white coloured spark plug insulators.
PROPERTIES OF WHITEWARE
• Whiteware does not allow fluids to pass through.
• It have low electrical condutivity.• It is chemically inert.• It has the ability to be made into complex
shapes.
Components of Whiteware
CLAY•PLASTIC COMPONENT•GIVES SHAPING ABILITY
FLINT•FORM OF SILICA USED AS FILLER•FILLER GIVES STRENGTH TO
SHAPED BODY
FELDSPAR•FLUXING AGENT•LOWERS THE MELTING
TEMPRATURE OF THE MIXTURE