Plastics that retain their plasticity on repeated heating are called
(a) thermosetting plastics
(b) thermoplastics
(c) thermal plastics
(d) none of these
Answers
Explanation:
Explain why some fabrics are called synthetics.
Ans. Some fabrics do not occur in the nature are hence called synthetic fibres.
2. Rayon is different from synthetic fibres because:
• It has a silk like appearance.
• It is obtained from wood pulp.
• Its fibres can also be woven like those of natural fibres.
• It is obtained from wood pulp.
Ans. It is obtained from wood pulp
3. Fill in the blanks with appropriate word:
a) Synthetic fibres are also called man-made or artificial fibres.
b) Synthetic fibres are synthesized from raw-materials called petrochemicals.
c) Like synthic fibres, plastic is also a polymer.
4. Give examples which indicate that nylon fibres are very strong.
option ( a)
The use of thermoset plastics has a number of advantages. Unlike thermoplastics, they retain their strength and shape even when heated. This makes thermosetting plastics well-suited to the production of permanent components and large, solid shapes