CH4

Question 1

Definition of polymer

Answer 1

Long chain molecule made up from combination of many repeating basic unit

Question 2

3 Types of polymer

Answer 2

Thermoplastic - can be repeatedly remoulded upon heating & cycled
Thermosetting - cannot be remoulded after heating
Elastomer - Can be stretched & return to original shape

Question 3

4 Characteristics of synthetic polymer

Answer 3

Good heat insulator
Inert & unreactive
Resistant to high heat
Lightweight, strong, hard

Question 4

7 Characteristics of natural rubber

Answer 4

Soft
Elastic
Low heat resistance
Electrical insulator
Easily oxidised
Reactive to chemical
Waterproof

Question 5

4 Process of coagulation of latex

Answer 5

Negatively charged protein membrane causes rubber particles to repel each other
Hydrogen ions from acid neutralises negatively charged protein membrane
Rubber protein collide with one another causing protein membrane to breake
Rubber polymers combine with one another that causes latex to coagulate

Question 6

Definition of vulcanisation

Answer 6

Process of producing more elastic & better quality rubber through production of cross-links between polymer chain

Question 7

3 Alternatives vulcanisation

Answer 7

Peroxides
Metal Oxides
Irradiation

Question 8

5 Characteristics of vulcanised rubber

Answer 8

Harder, Stronger, more elastic, more resistant to high heat & more resistant towards oxidation

Question 9

Definition of synthetic rubber

Answer 9

Synthetic polymer that is elastic in nature or elastomer polymer

Question 10

6 Characteristics of synthetic rubber

Answer 10

Hard
Elastic
Resistant to heat
Resistant to chemical
Resistant to oxidation
Heat insulator