1. Introduction Flashcards
1
Q
Soft Matter description (key property and consequence)
A
- Weak intermolecular forces of the order of thermal energy available at r.t.
- Solids that EASILY respond to weak external forces
-> Mechanical Deformation
2
Q
Types of soft matter
A
- Colloids (a dispersion of one phase in another such as emulsions or suspensions)
- Liquid Crystals (Self-organised fluid phases)
- Polymers
3
Q
Polymer Definition
A
A macromolecule made up of a large number of covalently linked repeat units/monomers
4
Q
Degree of polymerisation
A
Number of repeat units (n)
5
Q
Classification of synthetic polymers by mechanism
A
- Step growth (polycondensation)
- Chain growth (polyaddition/free radical pol.)
- other…
6
Q
Classification of synthetic polymers by thermal property
A
- Thermoplast: (plastic)
Retains the ability to flow above a certain temperature e.g. PET, PS - Thermoset:
Once formed, can’t become liquid again e.g. bakelite, rubbers
-> not re-mouldable
7
Q
Explaining sigmoid curve for tensile strength of alkanes with molecular weight
A
- Summation of intermolecular forces
- Chain entanglement
- Timescales of molecular movement