Test 1 Flashcards Preview

Polymer Chemistry > Test 1 > Flashcards

Flashcards in Test 1 Deck (11):
1

What is a thermoset polymer ?

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

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.

2

What is a thermoplastic polymer?

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

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

3

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

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

4

"... the y-axis is laballed '1/(1-p)', define or explain what the term represents

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

5

What is chitosan and provide a structure

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

6

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

linear

7

How would you prepare chitosan
(also provide a simple chemical equation)

Chitin + NaoH ---> Chitosan

8

Provide 3 examples for the use of chitosan

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

9

What is condensation polymerisation

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

10

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

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

Different types:
-Anionic
-Radical
-Cationic

11

When referring to polymer chemistry, define the ceiling temperature.

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