Macromolecules are found everywhere in our daily lives. They are produced from monomer units, small building blocks that can be polymerized to large molecules with different lengths (and, therefore, molar masses), structures, compositions, and end groups. If a macromolecule is synthesized using only one type of monomer with the same chemical structure, it is considered a homopolymer. If it comprises two different types of monomers, it is called a copolymer. In addition, terpolymers are polymers composed of three different monomers.
Since all technical polymerizations are statistical processes, a common feature of the vast majority of macromolecules is heterogeneity. The molar mass distribution is a well-known heterogeneity, and GPC/SEC is the method of choice to measure it.
In the case of copolymers, chemical composition is an additional heterogeneity that also governs the macroscopic product properties. Not only does the average percentage of comonomers present in the final product affect the material’s properties, but the distribution of the monomers along the chain also affects performance.
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