polydispersity


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polydispersity

[¦päl·i·di′spər·səd·ē]
(chemistry)
Molecular-weight nonhomogeneity in a polymer system; that is, there is some molecular-weight distribution throughout the body of the polymer.
References in periodicals archive ?
The polydispersity index (PDI) was acquired with a PL-GPC50 gel permeation chromatograph.
(a) DLS of colloidal silver dissolved in water showed an average size of 100 nm with a polydispersity index of 0.2.
Subsequently, a polycondensation reaction at an elevated temperature is carried out (usually at about 250[degree]C), with the use of an appropriate catalyst, resulting in a polycondensate mixture with a relatively high polydispersity. This method is not directly applicable to carbohydrates such as sucrose and inulin because these carbohydrates decompose at such high temperatures, and are not easily miscible with fatty acid methyl esters or oils.
Long-Oil Alkyd Resin Composition, Molecular Weight, and Polydispersity
The rigorous expressions for spinodal and critical points, considering the polydispersity of polymers, were derived by Koningsveld and Staverman [28]:
Measurements of Photochromic Nanocapsules Size and Polydispersity Index (PDI).
The number average molecular weights (Mn) and polydispersity index (P.I) of the polymer samples are given in the last two columns of Table 1.
The low-density metallocene polyethylene has 50,000 to 200,000 number average molecular weight and low polydispersity. The amount of low-density metallocene resin added to the regrind layer is 3 to 20 wt%.
The average molecular weights were [M.sub.n] = 3350 and [M.sub.w] = 8380, and polydispersity was 2.5.
For samples with polydispersity (PD) greater than about 1.5, these differences can significantly impact the analysis.
Researchers also want to determine polysaccharide molecular weight and polydispersity using a combination of total intensity light scattering and quasielastic light scattering techniques.