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The degree of polymerization, or DP, is the number of monomeric units in a macromolecule or polymer or oligomer molecule. [1] [2] [3]For a homopolymer, there is only one type of monomeric unit and the number-average degree of polymerization is given by ¯ ¯ = ¯, where ¯ is the number-average molecular weight and is the molecular weight of the monomer unit.
The total includes all degrees of polymerization: monomers, oligomers and polymers. This equation shows that a high monomer conversion is required to achieve a high degree of polymerization. For example, a monomer conversion, p , of 98% is required for X ¯ n {\displaystyle {\bar {X}}_{n}} = 50, and p = 99% is required for X ¯ n ...
The dextrose equivalent gives an indication of the average degree of polymerisation (DP) for starch sugars. As a rule of thumb, DE × DP = 120. As a rule of thumb, DE × DP = 120. In all glucose polymers , from the native starch to glucose syrup , the molecular chain ends with a reducing sugar, containing a free aldehyde in its linear form.
In linear polymers, the individual polymer chains rarely have exactly the same degree of polymerization and molar mass, and there is always a distribution around an average value. The molar mass distribution of a polymer may be modified by polymer fractionation. IUPAC definition for average degree of polymerization in polymer chemistry.
In chain-growth polymerization the propagation step is the addition of a monomer to the growing chain. The word kinetic is added to chain length in order to distinguish the number of reaction steps in the kinetic chain from the number of monomers in the final macromolecule, a quantity named the degree of polymerization. In fact the kinetic ...
A polymer can be described in many ways: its degree of polymerisation, molar mass distribution, tacticity, copolymer distribution, the degree of branching, by its end-groups, crosslinks, crystallinity and thermal properties such as its glass transition temperature and melting temperature.
The unusual buyout offer has upended Washington amid a flurry of executive orders and maneuvers by Trump and tech billionaire Elon Musk, who is head of Trump’s Department of Government ...
Since the degree of polymerization is a function of reaction time, the desired molecular weight can be obtained by quenching the reaction at the appropriate time. However, the polymer obtained in this manner is unstable in that it leads to changes in molecular weight because the ends of the polymer molecule contain functional groups that can ...