In
polymer science
Polymer science or macromolecular science is a subfield of materials science concerned with polymers, primarily synthetic polymers such as plastics and elastomers. The field of polymer science includes researchers in multiple disciplines inclu ...
, inherent viscosity is the ratio of the
natural logarithm
The natural logarithm of a number is its logarithm to the base of a logarithm, base of the e (mathematical constant), mathematical constant , which is an Irrational number, irrational and Transcendental number, transcendental number approxima ...
of the
relative viscosity of a polymer to its mass concentration. Inherent viscosity
scales
Scale or scales may refer to:
Mathematics
* Scale (descriptive set theory), an object defined on a set of points
* Scale (ratio), the ratio of a linear dimension of a model to the corresponding dimension of the original
* Scale factor, a number ...
inversely to
mass density
Density (volumetric mass density or specific mass) is the ratio of a substance's mass to its volume. The symbol most often used for density is ''ρ'' (the lower case Greek language, Greek letter rho), although the Latin letter ''D'' (or ''d'') ...
, and a common
unit
Unit may refer to:
General measurement
* Unit of measurement, a definite magnitude of a physical quantity, defined and adopted by convention or by law
**International System of Units (SI), modern form of the metric system
**English units, histo ...
is dL/g.
Inherent viscosity is defined as
where
is the
mass concentration of the polymer and
is the relative viscosity, which is defined as
where
is the viscosity of the solution and
is the viscosity of the solvent.
The definition of
is a
finite difference approximation to the derivative
That ideal limiting value is the
intrinsic viscosity, which is a good measure of the
polymerization degree.
References
Viscosity
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