Polymers

Question 1

Which polymers are easiest to deform?

Answer 1

Linear polymers with weak intermolecular forces.

Question 2

Does heat treatment work on polymers?

Answer 2

No.

Question 3

What are plastics?

Answer 3

Plastics are organic materials with high molecular weight.

Question 4

What are the types of plastic?

Answer 4

Thermosetting and thermoplastic.

Question 5

What are some examples of thermosetting polymers?

Answer 5

alkyl resin, silicon resin)

Question 6

What are some examples of thermoplastic polymers?

Answer 6

polyethene, polyester

Question 7

What are some advantages of plastic?

Answer 7

Light, strong, low melting points, good shock absorbers, insulators, chemically inert, corrosion and water resistant.

Question 8

What are some disadvantages of plastic?

Answer 8

Deformed under load, degrade upon extended

exposure to heat and UV.

Question 9

What is the monomer of PVC?

Answer 9

Vinyl Chloride

Question 10

What are elastomers (rubber)?

Answer 10

Rubbers are non-crystalline in nature and are high polymers that have elastic properties.

Question 11

How many types of rubber are there?

Answer 11

2: Natural and synthetic.

Question 12

What is corrosion?

Answer 12

Corrosion can be defined as any process of destructive disintegration or alteration of a metal or alloy caused by direct chemical attack or by electrochemical reaction with its environment.

Question 13

What is dry corrosion?

Answer 13

This type of corrosion occurs through direct
chemical action of the environment or atmospheric gases such as oxygen, halogen, H2S, SO2, N2 or anhydrous inorganic liquids in close
contact with the metal

Question 14

What is wet corrosion?

Answer 14

The conducting electrolytic liquid is in

contact with metal and two dissimilar metals are partially dipped in the electrolyte.

Question 15

What are polymers?

Answer 15

Polymers are generally macromolecules formed by the repeated linking of a large number of small molecules. Can be organic or inorganic.

Question 16

What is the structural unit of a polymer?

Answer 16

Structural unit of a polymer that combines together in a repeated fashion.

Question 17

What is polymerization?

Answer 17

Polymerization is a process in which a large number of small molecules combine to form a bigger molecule.

Question 18

What is degree of polymerization?

Answer 18

The number of repeating units or monomers present in a polymer chain is known as degree of polymerization

Question 19

What are Oligo polymers?

Answer 19

They are polymers with a low degree of polymerization

and have a 500–5000 molecular mass range.

Question 20

What are high polymers?

Answer 20

They are polymers with high degree of polymerization

and have a 10,000–2,00,000 molecular mass range.

Question 21

What is a homopolymer?

Answer 21

If the polymer consists of identical monomers, it is a homopolymer.

Question 22

What is a hetropolymer?

Answer 22

If the polymer consists of different types monomers, it is a hetropolymer or copolymer.

Question 23

What are the types of polymerization?

Answer 23

1. Chain growth polymerization
2. Condensation / Stepwise polymerization
3. Co-polymerization
4. Coordination polymerization.

Question 24

What is addition polymerization?

Answer 24

It is a reaction that yields a polymer which is an exact multiple of the original monomeric molecule.

Question 25

What is condensation polymerization?

Answer 25

This reaction involves the condensation of two functional groups present in the same kind of monomer or different kind of monomers by the elimination of small molecules

Question 26

What is copolymerization?

Answer 26

Co-polymerization is the joint polymerization of two or more different monomeric species.

Question 27

What is coordination polymerization?

Answer 27

Coordination or stereospecific polymerization involves directing the monomers in their approach to the growing polymer chain. Most often coordination polymerization is conducted using a catalyst. Involves initiation, propagation and term.

Question 28

What are the properties of polymers?

Answer 28

Strength, plastic deformation, crystallinity, chemical resistance.

Question 29

What does the strength of a polymer depend on?

Answer 29

Van der Walls forces, Covalent bonding, Chain length, slipping power.

Question 30

What is slipping power?

Answer 30

Resistance to slip and consequent deformation of a polymer, and slipping power mainly depends on shape of the molecule.

Question 31

What are amorphous polymers?

Answer 31

Polymers with long chains and bulky side

groups of low degree of symmetry. Weak intermolecular forces and flexible structure.

Question 32

What are crystaline polymers?

Answer 32

Linear chains allow a regular structure with increased intermolecular forces of attraction that lead to increased strength.

Question 33

What is Chemical resistance?

Answer 33

The chemical resistance of a polymer is decided by the nature of monomeric units and their molecular arrangement. Chemical attack causes softening, swelling and loss of strength of material.