Unit 1
| Assignment IV:
| 1 – F; 2 – F; 3 – T; 4 – F; 5 – T.
|
Unit 2
Assignment III: 1)
| Raw material
| Plastic
|
| 1.cellulose
| celluloid
|
| 2.petroleum and natural gas
| polyethylene, nylon, polyester
|
| 3. starch from plants (e.g. wheat)
| bioplastics
|
2) Possible answers:
| Advantages
| Problems
|
| 1. Plastics are versatile.
| 1. Plastics can be explosive.
|
| 2. Plastics are cheap.
| 2. Earlier people couldn’t make things of plastics to a high standard of quality.
|
| 3. Plastics are recyclable.
| 3. No good systems for collecting plastics for recycling.
|
| 4. Finding alternative raw materials.
| 4. Bioplastics are still expensive to produce.
|
| Assignment VI:
| 1 – F; 2 – F; 3 – F; 4 – F; 5 – T; 6 – F; 7 – T.
|
| Assignment VII:
| 1 – c; 2 – a/i; 3 – j; 4 – e; 5 – i/a; 6 – g; 7 – b; 8 – d; 9 – f; 10 – h.
|
| Assignment VIII:
| 1 – raw materials; 2 – production process; 3 – household appliances; 4 – construction industry; 5 – high precision components; 6 – injection molding.
|
Unit 3
| Assignment IV:
| 1 – e; 2 – g; 3 – d; 4 – i; 5 – b; 6 – j; 7 – h; 8 – c; 9 – f; 10 – a.
|
| Assignment V:
| 2), 3) 1 – PET; 2 – HDPE; 3 – PVC; 4 – LDPE; 5 – PP; 6 – PS.
|
Unit 4
| Assignment III:
| 1 – man-made polymer; 2 – textile fibers; 3 – chemical properties; 4 – expected life; 5 – medical devices; 6 – food containers.
|
Written Test 1 “Plastics”
| Vocabulary
| A)1 - e; 2 - c; 3 - a; 4 - d; 5 - f; 6 - b.
B) 1 - j; 2 - e; 3 - b; 4 - g; 5 - a; 6 - i; 7 - d; 8 - h; 9 - c; 10 - f.
C)1 - a; 2 - b; 3 - a; 4 - b.
|
| Reading
| A) 1 - b; 2 - j; 3 - e; 4 - f; 5 - g; 6 - a; 7 - h; 8 - i; 9 - d; 10 - c.
B) 1 - T; 2 - F; 3 - F; 4 - T; 5 - F; 6 - T; 7 - F; 8 - F; 9 - T; 10 - T.
|
Written Test 2 “Plastics”
| Vocabulary
| A)1 - b; 2 - c; 3 - a; 4 - b; 5 - b; 6 - a; 7 - a; 8 - c; 9 - b; 10 - c; 11 - a; 12 - a; 13 - b; 14 - c.
B)1 - f; 2 - a; 3 - c; 4 - e; 5 - d; 6 - b.
|
| Reading
| A) 1 - e; 2 - f; 3 - h; 4 - b; 5 - l; 6 - i; 7- k; 8 - j; 9 - a; 10 - d.
B) 1 - T; 2 - F; 3 - T; 4 - T; 5 - T; 6 - F; 7 - T; 8 – F; 9 - F; 10 - F.
|
Written Test 3 “Plastics”
| Vocabulary
| A) 1 - b; 2 - f; 3 - h; 4 - j; 5 - d; 6 - c; 7 - a; 8 - i; 9 - g; 10 - e.
B) 1 - a; 2 - b; 3 - d; 4 - b.
C) 1 - e; 2 - b; 3 - d; 4 - a; 5 - f; 6 - c.
|
| Reading
| Possible answers:
A) 1. Bulky items like ordinary buildings, bridges, dams, pavement, railroad ties, etc. are expensive to replace by plastics.
2. Due to plastics’ relatively low cost, ease of manufacture, versatility they have already displaced many traditional materials.
3. Elastomer is based on qualities classification.
4. Plastics can be classified by their chemical structure, chemical process, qualities and various physical properties.
5. The use of plastics is constrained chiefly by their organic chemistry.
6. Yes, they are. They are too expensive to replace wood, concrete and ceramic.
7. Plastics are still no match for metals like copper or aluminum.
8. Most plastics will melt or decompose when heated to a few hundred Celsius.
9. Polyesters are referred to the chemical structure of plastics.
10. The plastics physical properties are density, tensile strength, glass transition temperature, resistance to various chemical products, etc.
B) 1. Elastomers have sufficient cross-linking between molecules.
2. Polyvinyl chloride (PVC) is a colourless solid with outstanding resistance to water, alcohols, concentrated acids and alkalis.
3. Plastics are obtainable as sheets, thin films, fibers or granules.
4. Polyethene is a white waxy solid with very low density and low stiffness.
5. Polymer matrix composite (PMC) is synthesized so that all the fibers are lined up parallel to one another.
|
