Test 1

Question 1

What is a thermoset polymer ?

*Also, describe/list several characteristics of a thermoset polymer

Answer 1

DEFINITION: polymers that are joined together by chemical bonds acquiring a highly crosslinked polymer structure.

PROPERTIES:

• cannot be melted
• insoluble
• have crosslinks b/t chains
• doesnt soften when heated
• do not swell in the presence of certain solvents.

Question 2

What is a thermoplastic polymer?

*Also, describe/list several characteristics of a thermoplastic polymer

Answer 2

DEFINITION: a material that becomes soft when heated and hard when cooled.

PROPERTIES:
-Easy to melt
-can be recycled
-can be cooled and heated several times
have very week bonds b/t chains

Question 3

Provide 3 different examples of a natural polymer and explain the key differences between a natural polymer and a synthetic polymer.

Answer 3

Polysaccharides(starch, cellulose)
Nucleic acids(DNA, RNA)
Proteins(wool, silk)

Question 4

“… the y-axis is laballed ‘1/(1-p)’, define or explain what the term represents

Answer 4

Degree of polymerisation: the average number of monomeric units per molecule(polymer)

Question 5

What is chitosan and provide a structure

Answer 5

Chitosan is a linear polysaccharide composed of randomly distributed β–linked D-glucosamine and N-acetyl-D-glucosamine.

Question 6

Would you classify the arrangement of chitosan chains as linear, branched, star-shaped, net-worked, or combed ?

Answer 6

linear

Question 7

How would you prepare chitosan

also provide a simple chemical equation

Answer 7

Chitin + NaoH —> Chitosan

Question 8

Provide 3 examples for the use of chitosan

Answer 8

• Surfactants and antifoaming agents
• Hydraulic fluids
• Skin: dimethicone is used in skin moisturizing lotions

Question 9

What is condensation polymerisation

Answer 9

Repetitive condensation between two bifunctional monomers, with loss of some simple molecules such as water, alcohols, etc.

Question 10

What is addition polymerisation and list 3 different types of mechanisms?

Answer 10

The addition of monomer units to themselves to form a growing chain by chain reaction mechanisms.

Different types:

• Anionic
• Radical
• Cationic

Question 11

When referring to polymer chemistry, define the ceiling temperature.

Answer 11

a measure of the tendency of polymers to revert back to their monomers