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| A
macromolecule is a molecule of high molecular weight (about 106).
Polymer molecules are of this type and are assembled from building blocks
known as mers. A single diamond crystal could also be regarded as a macromolecule.
Macromolecules of a given chemistry will normally have a molecular weight distribution. The diagram illustrates a typical distribution of molecular weight and displays two averages that are used to characterize the distribution, the number average and the weight average. Number Average, MN = SxiMi , where x is the fractional number of molecules of molecular weight M. Weight Average, MW = SwiMi , where w is the weight fraction of molecules of molecular weight M. |
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| From:
Callister,
"Materials Science and Engineering," Wiley (1994) |
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