GCSE+Graphics+Materials+-+Polymers

toc =Polymers= Aesthetic, functional & mechanical properties, applications & advantages/disadvantages of the following thermoplastics for graphic products and commercial packaging:
 * Acrylic
 * Polethylene terephthalate (PET)
 * Polyvinyl Chloride (PVC)
 * Polypropylene (PP)
 * Polystyrene (PS), rigid (High Density Polystyrene) & expanded
 * Styrofoam

Research the above polymers and create two A3 sheets **with images** of examples and a bibliography.
 * Task 1**
 * 1) Your will research aesthetic properties of the material - //What does it look and feel like?//
 * 2) Research the mechanical properties - //What is the materials like? How does it behave if you try to bend it? Is it stiff, rigid, flexible, soft?//
 * 3) Research its functional properties - //What can it be used for//? //What is it generally used for? Which graphic product are made using this material?//
 * 4) After researching its applications//, - What are the advantages and disadvantages of using this materials for this product?//

=Injection Moulding=

This technique involves melting thermoplastic (which are also called thermoset plastics) and shaping them into required shapes that are then allowed to cool under controlled temperatures. The process begins with an engineer who designs the product. The mould maker then makes a mould that will fit the product that has been designed. Usually the mould has to be metallic, either steel or aluminium. Thermoplastics are then heated and the melted stuff is put into voids of the mould. It is then allowed to cool under controlled temperatures where it hardens into the required shape.

Regardless of machine type, producing a plastic injection-molded item involves seven basic steps. 1) Heat the plastic or other kind of resin using the required heat range for the object being produced. 2) Determine the size of the mold by using a reciprocating screw, which will convey the melted plastics into the front of the screw. 3) The plastics are injected into the mold, under necessary pressure. This will fill the cavities of the molds. 4) Pack the plastics, creating a fuller part inside the molds. 5) Let the plastics cool down in the mold using the desired cooling channel. 6) Eject the cooled plastics from the molds. 7) Pack the product and repeat the process. These steps may sound simple, but there are many more things involved with an injection molding process. However, this guide should provide the people new to plastic injection molding the basic understanding of what is really involved with this business.

Many goods can be produced due to the cheap and available raw materials. Some advantages are associated with this kind of molding. They are: Some disadvantages include the cost of the equipments used being too high, the need for specialists to design parts correctly thus increasing the cost and the general running costs are high.
 * Cost of labor is very cheap
 * Tolerance level of the raw material is high as it can be reused as many times as possible.
 * There is minimal finishing that is done on the products.
 * There is minimal scrap loss
 * Different materials can be used
 * High rate of production so we benefit from large economies of scales.


 * Reference:**
 * @http://www.design-technology.org/injectionmoulding3.htm**