• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Plastics are often frowned upon. This is because people often think of them as cheap and not aesthetically pleasing.

Extracts from this document...

Introduction

Plastics Plastics are often frowned upon. This is because people often think of them as cheap and not aesthetically pleasing. However they come in many different forms and often look very nice. Obviously there are types that do give the product a bad name. Mainly the cheap toys that are produced in the far east. This is not right and plastics should be seen as a real alternative and be able offer a huge amount of uses for this product. Polymers Polymers such as rubber, plastics and adhesives are organic structures. They can be natural, like amber and shellac, modified natural materials, like cellulose and casein, or synthetic, like nylon and polypropylene. ...read more.

Middle

When subjected to pressure, thermoplastics can deform in two ways. Elastic deformation occurs in which the initially curled long chains stretch out and this deformation is recovered when the pressure is removed. At higher temperatures or pressures, viscous or plastic deformation occurs in which the secondary bonds weaken and allow the molecular chains to slide over each other. This weakening of the bonds at higher temperatures means that thermoplastics are easy to cast or form. Thermosets Thermoset polymers are formed by a condensation reaction which forms strong, primary cross-linking bonds between adjacent polymer chains, giving them a rigid three-dimensional structure in which the atoms cannot move easily. Heating helps this cross-linking process and so the polymer hardens as it is heated. ...read more.

Conclusion

The tool costs are much lower than for presswork and it is possible to get high-quality finish, which is difficult when pressing SNICs, for example. One disadvantage is that the stress levels required to deform the material cannot be too high and this limits the materials which can be used and the shapes that can be generated. Bending Plastics can be bent in many ways. By using heat the bonds in the plastics become separated and malleable. This enables the plastic (usually in sheet form) to be bent. Both thermo and thermosetting plastics can be bent however thermosetting plastics can not then be reformed. If the plastic gets too hot however it will begin to deform. The structure and the appearance of the plastic will therefore change. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Resistant Materials section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Resistant Materials essays

  1. People always use plastic things in their daily life but generally they do not ...

    That helps police to act as quickly as any person who do not have a vest. Because of these crucial effects in healthcare and safety, plastic is indispensable for people since its invention. The greatest impact of plastics can easily be seen in advanced technology.

  2. EFFECT OF MOISTURE ON THE MECHANICAL PROPERTIES OF NYLON

    Type of Nylon Equilibrium@50%R.H. Equilibrium @Saturation 6 2.7 9.5 6/6 2.5 8.0 6/10 1.5 3.5 6/12 1.3 3.0 11 0.8 1.9 12 0.7 1.4 Water molecules produce polar bonds with the amide groups in the Nylon molecules. Although small, water molecules take up space and displace the Nylon molecules.

  1. My aim of this experiment is to recognize which material is the greatest sound ...

    material is the worst insulator of sound as it firstly has the highest gradient rating of 8.5 and also detects a large value of 86 decibels on the first layer of insulation, and slowly decreases. However with Polystyrene, it is clearly evident from the graph that this is the best

  2. Thermal Conductivity.

    Record the time for each of the sample materials do it three times for accurateness, and then take the average. Result The results are as follows: Material Test 1 time(mins/secs) Test 2 time(mins/secs) Test 3 time(mins/secs) Average time(mins/secs) Copper 50s 48s 51s Brass 1m10s 1m07s 1m15s Glass 12m11s 13m21s

  1. The task has been set to make a hole punch (used to punch holes ...

    Produce accurate holes of high quality Aesthetics - how the product looks My hole punch must:- 1. Look attractive 2. Appear professional 3. Have a suitable finish 4. Be in proportion Ergonomics - adjusting the product to suit the user My hole punch must:- 1. Weigh less than 1kg 2.

  2. The Progression of the Sail Boat from Past to Present and beyond

    The engineers needed to allow the boat to sail closer to the wind on a narrower angle of attack. The first successful designs appeared on the Red Sea called the 'Arab Dhows'. Another design included the 'Bristol Channel Cutters' around England that also proved itself as an effective windward sailing vessel.

  1. Report identifies three bio-engineered products that have been developed during the last 50 years, ...

    Their latest breakthrough, the AbioCor, allows the artificial heart to be implanted directly into the human body. Unlike previous heart assist devices, the AbiCor allows the user optimal manoeuvrability, as they are no longer connected to large machines that power the heart.

  2. Investigation into the physical properties of glass.

    This means that if tempered glass is in place in a skylight or high window by law a safety screen may have to be implemented. Physical properties of tempered glass. 11, 17, 18, 19, 10 In my research I found that some sources differed I the values given.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work