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Molecular weight single-point method

A simple way to estimate the molecular weight of PBIs is the measurement of intrinsic viscosity (f/iv) of the polymer in solution at a fixed temperature (normally 25-30 °C). The intrinsic viscosity is obtained by plotting the specific viscosity (tj p) as a function of the polymer concentration and extrapolating to zero concentration. In order to simplify the measurement process, a single-point method was proposed to calculate the tjiy from using (7.1) [35,50-52], where C is the polymer concentration in a concentrated acid, e.g., 96 wt% sulfuric acid. [Pg.154]

The molecular weight of SAN can be easily determined by either intrinsic viscosity or size-exclusion chromatography (sec). Relationships for both multipoint and single point viscosity methods are available (18,19). Two intrinsic viscosity and molecular weight relationships for azeotropic copolymers have been given (20,21) ... [Pg.192]

The molecular weight of cobalt chloride as determined by the freezing-point method, with urethane as solvent, corresponds to the double formula, Co2Cl4 (compare ferrous chloride),1 but the results obtained by the boiling-point method 2 indicate that under those conditions the molecule is single, namely, CoCl2. [Pg.42]

See other pages where Molecular weight single-point method is mentioned: [Pg.183]    [Pg.111]    [Pg.183]    [Pg.154]    [Pg.111]    [Pg.501]    [Pg.1136]    [Pg.337]    [Pg.8]    [Pg.1136]    [Pg.493]    [Pg.172]    [Pg.151]    [Pg.81]    [Pg.274]    [Pg.87]    [Pg.250]    [Pg.102]    [Pg.103]    [Pg.152]    [Pg.157]    [Pg.157]    [Pg.40]    [Pg.61]    [Pg.1136]    [Pg.337]    [Pg.328]    [Pg.1374]    [Pg.376]    [Pg.19]    [Pg.12]    [Pg.204]    [Pg.37]    [Pg.38]    [Pg.18]    [Pg.179]    [Pg.476]    [Pg.403]    [Pg.200]    [Pg.99]    [Pg.397]    [Pg.68]    [Pg.144]    [Pg.220]    [Pg.27]    [Pg.120]    [Pg.205]   
See also in sourсe #XX -- [ Pg.154 ]



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Molecular weight methods

Molecular weight point

Point method

Single-molecular

Single-point

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