molecular-weight distribution

molecular-weight distribution

[mə′lek·yə·lər ¦wāt ‚di·strə′byü·shən]
(organic chemistry)
Frequency of occurrence of the different molecular-weight chains in a homologous polymeric system.
References in periodicals archive ?
The contents of EU rubber, extracted from leaves of Eucommia ulmoides, were determined by the gravimetric method, and the molecular-weight and molecular-weight distribution were determined by gel permeation chromatography (GPC).
log G" plot is independent of the molecular weight, the short-branch length, and the testing temperature, it depends strongly on the molecular-weight distribution, and the degree of long-chain branching and its distribution (8).
Its molecular weight is slightly higher than standard PS, and it has a much broader molecular-weight distribution.
The narrow molecular-weight distribution and broad crystallinity distribution of Versify copolymers result in improved temperature performance over that of similar metallocene products.
The "super-strength" resins have a narrower molecular-weight distribution and more homogeneous short-chain branching distribution than the conventional hexene resins, leading to a lower elasticity and less orientation in the film, and a lower concentration of lower-molecular weight species for improved film blocking.
Basell has two new grades of Metocene mPP homopolymers for injection molding, both of which are nucleated and have very narrow molecular-weight distribution.
The effect is temporary and is accomplished without additives, change in molecular-weight distribution, or any performance tradeoff, says Coperion.
Irgatec CR 76 is a non-peroxide modifier that provides controlled degradation of a low-MFR PP into a high-flow resin with narrow molecular-weight distribution.
Versify polymers have narrow molecular-weight distribution but broad composition and crystallinity distribution, which is said to result in improved heat resistance compared with metallocone-based products of comparable olefin content.

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