Upload
isaac-oconnor
View
222
Download
0
Tags:
Embed Size (px)
Citation preview
SYNTHETICMATERIALS
INTRODUCTION
Man has been using many naturally occurring materials like Cotton, silk and jute to prepare fibres and clothes.Shikakai was used for cleaning.A long list of products like gum, resin, dyes, wood and many more which are very useful to us exists. In ancient days all needs of human beings were fulfilled by naturally available substances
WHY IS THE NEED FOR SYNTHETIC MATERIALS INCREASED..?
INCREASE IN POPULATION.
LIMITED AVAILABILITY OF NATURAL RESOURCES.
SLOW PROCESSING OF NATURAL RESOURCES.
LETS UNDERSTAND WHAT EXACTLY SYNTHETIC
MATERIALS MEAN..!
Materials not available in nature but produced by using naturally available raw materials, are called synthetic materials. Examples: Plastics, Cement, Glass, Fibres, Ceramics etc.
WHAT IS A POLYMER?
Compounds which are formed by the union of a very large number of molecules of a simple compound or compounds united in a repetitious manner are called polymers.The simple compounds which build up the polymer molecule are called monomers.The process in which two or more molecules of a simple compound unite together to form a new compound is called polymerisation.
POLYMER TYPESNON -SYNTHETIC
SYNTHETIC
FOUND IN NATURE.
THEY ARE SYNTHESISED
PROTEINS, CARBOHYDRATESFATS, NUCLEIC ACID
NYLON, TERYLENE, POLYTHENE
SYNTHETIC POLYMERS
ADDITION POLYMERS: Addition polymerisation is a process in which several molecules join together to form a giant molecule during the reaction. There is no elimination of molecules. They are prepared from unsaturated monomers. E.g.. Polythene and polyvinyl chloride (pvc).
SEE HOW ITS MADE:https://www.youtube.com/watch?feature=player_detailpage&v=U6d_F1jcKzI
CONDENSATION POLYMERS:
The polymerisation in which several monomers form a polymer with the elimination of some simple molecules during the reaction is called condensation polymerisation.The condensation involves elimination of molecules like water, methanol etc. Leading to linking of polymers. E.g. Nylon and terylene.
SEE HOW CONDENSATION REACTION TAKES PLACE..!!
POLYMER APPLICATIONS:MONOMERS POLYMERS USES
ETHENE POLYTHENE BAGS,FILMS
ESTERS POLYESTERS SYNTHETIC FIBRES
VINYL CHLORIDE POLY VINYL CHLORIDE
PVC TUBES
TETRAFLUROETHENE
TEFLON COATING VESSELS
CHLOROPRENE NEOPRENE NATURAL RUBBER,HOUSE HOLD & MEDICAL ARTICALS
ETHYLENE CHLORIDE+SODIUM POLYNIHIFIDE
THIOKOL GASKETS,STEALS,HARD RUBBER ARTICLES
CARBOPOLYTHENELACTOM
NYLON FIBRE, BRUSHES, ROPES
PLASTICSA plastic is a synthetic material manufactured by the polymerisation of organic substances which can be moulded in to desired shape when hot. Plastics are of two types (1) Thermo plastics (2) Thermosetting plastics.
WHY PLASTIC IS USED SO EXTENSIVELY..?
> Plastic materials are strong and more durable. > They are less corrosive and do not react with the atmospheric air.> It can be shaped easily.> Plastics have replaced glass, wood, metal, rubber, leather etc.
PLASTIC & ITS CLASSIFICATIONA plastic is a synthetic material manufactured by the polymerisation of organic substances which can be moulded into desired shape when hot.Plastics are of two types:(1) Thermo plastics (2) Thermosetting plastics.
THERMOPLASTIC PLASTIC: Plastics which lose their shape on heating are called thermoplastics.E.g. Polyvinyl chloride, Polystyrene are examples for thermo plastics.THERMOSETTING PLASTIC: Plastics which set on heating and become irreversibly hard on cooling, are known as thermosetting plastics.E.g. : Bakelite, silicones, epoxy-resins.
PLASTIC TYPES
How am I made???
https://www.youtube.com/watch?feature=player_detailpage&v=U6d_F1jcKzI
RECYCLING OF PLASTIC
Steps involved in re-cycling are:1. Collection of waste plastic materials.2. Separating thermosetting and thermoplastic materials.3. Softening of thermoplastics.4. Upgrading the quality by refining.5. Re-moulding.
SEE HOW THAT CAN BE DONE!!!!!!
https://www.youtube.com/watch?feature=player_detailpage&v=Q6hzhKmw4EY
WHAT IS CEMENT..??> Cement is an important synthetic material.> It is the chief component of building materials. > Cement is a mixture of calcium silicate and calcium aluminate, with small amount of gypsum salt.> The essential raw materials used in the manufacture of cement are clay and lime stone. >Gypsum (calcium sulphate) is used to regulate setting rate.
EVER WONDERED HOW CEMENT IS MANUFACTURED..?
https://www.youtube.com/watch?feature=player_detailpage&v=U6d_F1jcKzI
CEMENT SETTING AND CURING
Cement sets into a hard mass when mixed with water.
Therefore it makes an excellent binding material in construction work.
The method of hardening cement by treating it with water is known as curing.
During curing cement absorbs water. Calcium silicate and aluminates of cement
are converted into a colloidal gel. This process is exothermic; hence it
requires continuous water treatment.
GLASSGlass is one of the oldest syntheticsubstances being used. Due to its transparentand non-corrosive property, glass is widelyused in various fields. Chemically, glass isa homogenous mixture of sodium silicate andcalcium silicate (Na2SiO2, CaSiO3, 4SiO2)
MANUFACTURE OF GLASS!!!!
Do you know that I am made of opaque substances but I am transparent!!!!
Na2CO3 + SiO2 → Na2SiO3 + CO2
CaCO3 + SiO2 → CaSiO3 + CO2
Check this out !!!!
https://www.youtube.com/watch?feature=player_detailpage&v=-z1P2cK9Rro
PROPERTIES OF GLASS
Glass is a strong and transparent material. It is corrosion resistant
It does not react with other chemicals at ordinary temperature.
It gradually softens on heating, and begins to flow very slowly.
SL.n
TYPES SPECIAL ADDITIVES
PROPERTY
USE
1Soda Glass
Aluminium oxide
Fuses easily at relatively low Temperature
Window panels, bottles, tumblers
2BorosilicateGlass
Boron Withstands high temperature fluctuations
LaboratoryEquipments.
3.
Lead glass
Lead oxidepotassiumcarbonate
Highly transparent; high refractive index; absorbsradiations
Lenses, prisms, window panels of nuclear installations
SL.n
TYPES SPECIAL ADDITIVES
PROPERTY
USE
4.Colouredglass
Metaloxide
Choice of the metal oxide depends on the colour to be imparted to it.
Window panels, decorative materials
5.Safety glass
Synthetic plastic is sandwiched between the two thin glass sheets
Withstands high stress
Windshields ofautomobiles,bullet-proof glass
6.
Fibre glass
Molten glass is drawn into thin fibres & sheets are prepared
Light strong and fire proof
Fire proof curtain dresses, parts of automobile
CERAMICS
Clay materials, such as chinaware, porcelain and bricks, are collectively known as ceramics.
.The word ceramic is derived from a Greek word
ceremos which means earthern pot.
WATCH OUT HOW AM I MADE!!!
I am made from white clay, sand and feldspar. [Feldspar, K2O Al2O3 6SiO2]
https://www.youtube.com/watch?feature=player_detailpage&v=w_psIFCFY1w
LETS ALL SAY NO TO PLASTICS!!!!!!
EVERY ONE NEEDS TO DO THEIR BIT!!!!!
&
THINK
HOPE YOUENJOYED