Corrosion Engineering Multiple Choice Questions on “Corrosion of Plastics and Elastomers”.
1. The polymer is a large and heavy molecular chain formed from the interaction of many monomeric units.
a) True
b) False
Answer: a
Clarification: Polymers are the large and heavy molecular chains formed from the interaction of many monomeric units. It includes plastics, elastomers, and materials like polystyrene, etc.
2. Which of the following is/are characteristics of plastics?
a) High stiffness and strength
b) Less thermal and electrical conductivity
c) High corrosive resistance
d) High stiffness and strength, less thermal and electrical conductivity and high corrosive resistant
Answer: d
Clarification: Plastics are one of the classifications of polymers. It has high stiffness and strength, less thermal and electrical conductivity, and high corrosive resistance.
3. Which of the following statement is/are correct regarding elastomers?
a) It has high elastic properties
b) It has weak intermolecular forces of attraction between molecules
c) Rubber is a good example of an elastomer
d) Elastomers have high elastic properties, weak intermolecular forces of attraction and rubber is a good example of an elastomer
Answer: d
Clarification: Elastomers are the part of polymers which have high viscous and weak intermolecular forces of attraction between molecules. It has high elastic properties such as high resilience, elastic deformation. Rubber is a good example of an elastomer.
4. The corrosion mechanism of polymeric and metallic materials are the same in all corrosive environments.
a) True
b) False
Answer: b
Clarification: Polymeric materials corrode differently rather than processes associated with metallic corrosion. Metallic corrosion results in the electrochemical reactions with the dissolution of metal into metal ions. Whereas polymers result in physicochemical processes.
5. Which of the following is/are the physicochemical processes that occur in polymers?
a) Swelling
b) Dissolution
c) Bond rupture
d) Swelling, dissolution and bond rupture
Answer: d
Clarification: The physicochemical processes that occur in polymers due to the corrosive environment are:
6. Which of the following is/are the causes for the bond rupturing in polymers?
a) Chemical reaction (oxidation)
b) Heat
c) Radiation (sunlight)
d) Chemical reaction, heat, and radiation
Answer: d
Clarification: Causes for the bond rupturing in polymers are:
7. Which of the following is/are the effects of polymeric corrosion?
a) Alteration of mechanical properties
b) Cracks formation due to internal stress
c) Loss of appearance
d) Alteration of mechanical properties cracks formation due to internal stress and loss of appearance
Answer: d
Clarification: Effects of polymeric corrosion:
- Alteration in physical, chemical and mechanical properties
- Cracks initiation and formation due to internal stress
- Loss of appearance.
8. Which of the following is depicted in the given figure?
a) Metallic dissolution
b) Polymer-solvent interaction
c) Mechanism of polymeric degradation
d) Uniform corrosion of metals
Answer: b
Clarification: The given figure describes various layers formed by polymer-solvent interaction. These layers are solvent, liquid layer, Gel layer, Solid swollen layer, Infiltration layer, and polymer.
9. Which of the following corrosive environments that mostly results in polymeric dissolution?
a) Strongly oxidizing environments
b) Strong acids
c) Strong alkalis
d) Strong oxidizing environments, acids, and alkalis
Answer: d
Clarification: Corrosive environments that mostly results in polymeric dissolution are:
- Strong oxidizing environments
- Strong acids
- Strong alkalis
- Water-miscible solvents
- Strong solvents.