D6 Basic Polymer Properties 2

Question 0

What are insoluble polymers often capable of forming? And what are they used in?

Answer 0

Forming thin films

Used in tablet coating, wound dressings membranes etc

Question 1

What can water soluble polymers potentially be able to do? And what are water soluble polymers useful as?

Answer 1

Increase viscosity of solvents
Swell/ change shape
Adsorb at surfaces

Useful as suspending agents

Question 2

What is rate of dissolution of a water soluble polymer dependent on?

Answer 2

Molecular weight

Question 3

What is the equation of velocity of penetration (S) of a solvent into a bulk polymer and what does each component stand for?

Answer 3

S=kM^-A
K and A are constants
M - polymer molecular weight

Question 4

What happens to the structure if the polymer-solvent interaction is better?

Answer 4

More open and expanded the polymer structure would be

Question 5

In a poor solvent which interaction will be greater and what happens?

Answer 5

Polymer-polymer interactions greater than solvent /polymer so later likely to coil up

Question 6

What happens if the charge of a polymer neutral?

Answer 6

Polymer contracted, low viscosity

Question 7

What happens if a polymer ionised?

Answer 7

Groups repel expanded structure increased viscosity

Question 8

How can polymer gels be formed?

Answer 8

Swelling of a highly cross linked polymer

By making a dissolved polymer less soluble (increasing polymer -polymer interactions)

Question 9

Is type 1 or 2 gels reversible?

Answer 9

Type 1 irreversible

Type 2 heat reversible