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molecules of low relative molecular mass. Notes. 1. In many cases, especially for synthetic polymers, a molecule can be regarded as having a high relative molecular mass if the addition or removal of one or a few of the units has a negligible effect on the molecular properties. This statement
M phase See mitosis. macromolecule Any very large molecule composed of dozens, hundreds, or thousands of covalently bonded atoms, especially one with biological significance. . Many important biomolecules, such as nucleic acids and proteins, are polymers consisting of a repeated series of smaller monomers; others such as lipids and carbohydrates may not be polymeric but are nevertheless large ...
The seniority of the subunits does not need to be followed. For single-strand (co)polymers, a dash is drawn through the enclosing marks, e.g., poly[oxy(ethane-1,2-diyl)] shown below left. For irregular polymers, the CUs are separated by slashes, and the dashes are drawn inside the enclosing marks.
Polymers, strictly speaking, comprise most solid matter: minerals (i.e. most of the Earth's crust) are largely polymers, metals are 3-d polymers, organisms, living and dead, are composed largely of polymers and water. Often polymers are classified according to their origin: biopolymers; synthetic polymers; inorganic polymers
Polymers, both natural and synthetic, are created via polymerization of many small molecules, known as monomers. Their consequently large molecular mass , relative to small molecule compounds , produces unique physical properties including toughness , high elasticity , viscoelasticity , and a tendency to form amorphous and semicrystalline ...
Prior to Staudinger's work, polymers were understood in terms of the association theory or aggregate theory, which originated with Thomas Graham in 1861. Graham proposed that cellulose and other polymers were colloids, aggregates of molecules having small molecular mass connected by an unknown intermolecular force.
All polymers are made of repetitive units called monomers. Biopolymers often have a well-defined structure, though this is not a defining characteristic (example: lignocellulose ): The exact chemical composition and the sequence in which these units are arranged is called the primary structure , in the case of proteins.
Polymer molecules, even ones of the same type, come in different sizes (chain lengths, for linear polymers), so the average molecular mass will depend on the method of averaging. The number average molecular mass is the ordinary arithmetic mean or average of the molecular masses of the individual macromolecules.