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Topics. Introduction to PlasticsRaw Materials to PlasticsThe Finished ProductsSpecial Applications. Introduction to Plastics . What products in your class are made out of plastic?The automobile could not be nearly as efficient with out the use of plastics.What are some of the different characte
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1. The World of Plastics Applied Tech. Ed. I
Teacher Education
Red River College
2. Topics Introduction to Plastics
Raw Materials to Plastics
The Finished Products
Special Applications
3. Introduction to Plastics What products in your class are made out of plastic?
The automobile could not be nearly as efficient with out the use of plastics.
What are some of the different characteristics of the various plastics found in a car?
4. Raw Materials to Plastics Celluloid was the first plastic to be made.
1860 Alexander Parkes produced celluloid and patented the product in 1865.
In 1870 John Hyatt worked out the Parkes’ technical difficulties without any theoretical understanding.
5. Raw Materials to Plastics cont… In 1920 a German chemist Hermann Staudinger developed a theory dealing with the chemical nature of a whole group of substances, natural and synthetic. He called them “macromolecules” Today we call them polymers.
In 1953 he received the Nobel Prize for his discovery.
Staudinger provided the foundation for the world of plastics as we know it today.
6. Raw Materials to Plastics cont… Plastics were produced from natural raw materials. Protein from milk was used to make artificial horn.
Using Rennin, the enzyme obtained from the stomach of a calf, the casein was precipitated, washed, dried and ground. It was then processed coloured and harden to form buttons.
7. Plastics as a Concept Plastics in the broadest sense include organic materials which are based on Polymers which are produced by the conversion of natural products by synthesis from primary chemicals coming from oil, gas or coal.
8. Plastic Materials Composite Materials
Consist of a continuous matrix , often a resin surrounding a fibrous reinforcing structure.
Typically glass, carbon, boron fibres in the form of continuous filament reinforce woven fabrics.
Fishing rods
Racquets
Hockey stick shafts
Canoes & boats
9. Polymeric Materials Polymers are classified according to their origin and method of synthesis.
Natural Products
Cellulose (wood, cotton) horn, rosins, raw rubber
Vulcanized rubber, vulcanized fibre, celluloid
Synthetic Polymers
Thermoplastics moldable without undergoing significant change.
Thermosetting plastics are rigid and the molecules are cross-linked in three dimensions.
Elastomers have fewer linkages than thermosets and are rubbery.
10. Identification Tests Transparency
Density
Thermal Behaviour
Flammability
Fracture type
Solubility
Heat conductivity
11. Thermosetting Plastics
12. Thermoplastics
13. How can you implement the Coding System? Application:
The Plastics Coding System is designed to be easy to read at a glance and distinguishable from other marks put on rigid plastic containers by manufacturers for use in processing and identification.
The system uses a triangular-shaped symbol composed of three arrows, with a number in the centre indicating the material from which the bottle is made, as follows:
14. Recycling?? Coding System