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प्रश्न
What are thermoplastic polymers?
What are thermoplastics?
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उत्तर १
Their properties are between those of elastomers and fibers. These polymers are called thermoplastics as, on heating, they become soft and, on cooling, become hard. Hence, these polymers can be remoulded and recycled.
Example: Polyvinyl chloride (PVC).
उत्तर २
- The polymers in which the intermolecular forces of attraction are intermediate to those of elastomers and fibres are called thermoplastics.
- There is no cross-linking between polymeric chains in thermoplastics, which are linear polymers.
- Thermoplastics soften when heated because of the presence of moderate (not very strong) intermolecular forces of attraction.
- They are rather firm at ambient temperature but mushy and gooey when heated.
- But when they cool, they solidify once more.
- They are easily molded by heating since heating does not result in cross-linking.
संबंधित प्रश्न
Write the names and structure of the monomers of the following polymers:
Nylon-6, 6
Which of the following is a fibre? Nylon, neoprene, PVC
Write the names of monomers of the following polymers.
Write the names of monomers of the following polymers:
How can you differentiate between addition and condensation polymerisation?
How is dacron obtained from ethylene glycol and terephthalic acid?
How are the following polymers prepared?
Orlon
Write a note on aldol condensation.
Name the monomers and the type of polymerization in each of the following polymers:
Bakelite
Write the name of the monomer of the following polymer:
Bakelite
Write the structures of monomers used the following polymers:
Nylon - 6, 6
Which of the following polymers can have strong intermolecular forces?
(i) Nylon
(ii) Polystyrene
(iii) Rubber
(iv) Polyesters
Match the polymers given in Column I with their main applications given in Column II.
| Column I | Column II |
| (i) Bakelite | (a) Unbreakable crockery |
| (ii) Low-density polythene | (b) Non-stick cookwares |
| (iii) Melamine-formaldehyderesin | (c) Packaging material for shock absorbance |
| (iv) Nylon 6 | (d) Electrical switches |
| (v) Polytetrafluoroethane | (e) Squeeze bottles |
| (vi) Polystyrene | (f) Tyre, cords |
Assertion: Polyamides are best used as fibres because of high tensile strength.
Reason: Strong intermolecular forces (like hydrogen bonding within polyamides) lead to close packing of chains and increase the crystalline character, hence, provide high tensile strength to polymers
A raw material used in making nylon is
Perion is
Wash and wear clothes are manufactured using
Melamine is
Nylon – 6 is made from
Which is used for the formation of nylon – 6?
The polymer formed on heating Novolac with formaldehyde is ______.
The polymer containing strong intermolecular forces, e.g., hydrogen bonding, is ______.
