Question

In Polymer chemistry, give a description on a specific characterization method This can include: Mechanical properties Thermal properties Interacition among molecules Crystallinity Molecular Weight Diffisuion into Gas Layers. A few methods include: Surface Analysis, Image analysis, Structural analysis, Organic Analysis, and Elemental Analysis.

Answer 1

We can use following techniques for analysis of any polymer

a) Surface area analyzer

b) X-ray Diffraction Technology

c) Scanning Electron microscopy

d) Transmission electron microscopy

e) Nuclear Magnetic resonance

f) FT-Infra Red spectroscopy

g) Element analysis

h) End-group analysis

i) electron spin resonance spectroscopy

j) Thermal analysis (TGA-DSC) etc

There are different techniques for measuring the molecular weight of polymers (average molecular weight) viz end group analysis, osmometry, viscometry and light scattering method (based on colligative property of polymeric solution)

A more sophisticated technique is Static light Scattering (SLS).

Rayleigh Equation

In this technique, the polymer is irradiated with a particular intensity of light photons. The polymer absrob the light and re-emit (or scatter) the light in different directions. The light scattered by the polymer is proportional to the moelcular weight of polymer. The relation is based on Rayleigh equation.