spatial arrangement of atoms in a macromolecule. Determined
by the values of bond angles and lengths of the corresponding bonds.
Description
The configuration of a macromolecule
is determined by the relative positions of its constituent monomer units and
their structure. Today, the term "structure", or "primary
structure", is usually used to describe configurations of macromolecules.
There are two configuration orders: short-range (bonding configuration of neighbouring units) and long-range (characterises the structure of sufficiently long sections of macromolecules). A quantitative measure of tacticity (order) is the degree of stereoregularity. In addition, tacticity can be described as the number of different types of nearest neighbour pairs (di-, tri-, tetrads), whose distribution is determined by experiments. For example, the quantitative characteristic of configuration in statistical cross-linked macromolecules is the density of crosslinking, i.e. the average polymerisation degree of the chain section between neighbouring grid points.
The configurations of macromolecules are determined using X-ray structure analysis, IR spectroscopy, NMR, birefringence, etc. Usually each method is the most "sensitive" to some configuration characteristic, e.g. in many cases NMR can quantitatively characterise the short-range configuration order in homo- and copolymers.
There are two configuration orders: short-range (bonding configuration of neighbouring units) and long-range (characterises the structure of sufficiently long sections of macromolecules). A quantitative measure of tacticity (order) is the degree of stereoregularity. In addition, tacticity can be described as the number of different types of nearest neighbour pairs (di-, tri-, tetrads), whose distribution is determined by experiments. For example, the quantitative characteristic of configuration in statistical cross-linked macromolecules is the density of crosslinking, i.e. the average polymerisation degree of the chain section between neighbouring grid points.
The configurations of macromolecules are determined using X-ray structure analysis, IR spectroscopy, NMR, birefringence, etc. Usually each method is the most "sensitive" to some configuration characteristic, e.g. in many cases NMR can quantitatively characterise the short-range configuration order in homo- and copolymers.
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