GPC/SEC Basic Theory 1. What is a Polymer?

Hello!  

Last week, we introduced the GPC/SEC equipment, so today I will inform you about the basic theory related to it.

1. Basic Concept

(1) What is a Polymer?

-A polymer is made by the chemical bonding of small identical molecules called monomers.

-The chemical bonding process is called “polymerization”.

-Polymerization creates polymer molecules or polymer chains.

-A polymer is a kind of mixture consisting of molecules with different molecular weights.

-A polymer refers to molecules with a molecular weight ranging from thousands to millions.

In other words, polymer molecules or chains are made from the same monomer of different lengths.

Example of a Polymer – Polymerization of vinyl chloride to make Polyvinyl chloride (PVC)

(2) Classification of Polymers

① Thermoplastics

-Long chain structure

-Becomes fluid above a certain temperature.

-If an appropriate solvent is used, the chain structure between molecules unravels and dissolves.

② Thermosets

-The molecular chains are crosslinked, forming a three-dimensional network structure.

-Does not melt upon increasing temperature.

-Does not dissolve in a solvent, only swells.

(3) Form of Polymers

① Long polymer chains indicate a high degree of polymerization (DP), while shorter polymer chains indicate a low degree of polymerization.

② Apart from the length of the polymer’s chain, the degree of branching holds significant importance.