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If both ratios are near 1, a given monomer will add the two monomers with comparable speeds and a statistical or random copolymer is formed. r 1 ≈ r 2 ≈ 0 {\displaystyle r_{1}\approx r_{2}\approx 0\,} If both values are near 0, the monomers are unable to homopolymerize.
It is referred to as the Purple Book. It was published in 1991 (ISBN 0-63202-8475) by Blackwell Science. The author of this book is W.V. Metanomski. The expansion of this book named Compendium of Polymer Terminology and Nomenclature: IUPAC Recommendations, 2008 was published by the Royal Society of Chemistry in 2009 (ISBN 978 0 85404 491 7).
In this equation, P is the polymer while x represents degree of polymerization, * means active center of chain-growth polymerization, M is the monomer which will react with active center, and L may be a low-molar-mass by-product obtained during chain propagation. For most chain-growth polymerizations, there is no by-product L formed.
A polymer is a substance composed of macromolecules. The latter usually have a range of molar masses (unit g mol −1), the distributions of which are indicated by dispersity (Đ). It is defined as the ratio of the mass-average molar mass (M m) to the number-average molar mass (M n) i.e. Đ = M m /M n. [4]
The degree of composition drift is directly affected by the reactivity ratios of each monomer in the copolymer system. Both the Mayo-Lewis equation and plot of the equation make evident that as monomer conversion increases, the copolymer composition will drift as the preferences for monomers change due to the interaction between reactivity ...
General scheme ionic propagation. Propagating center can be radical, cationic or anionic. In polymer chemistry, ring-opening polymerization (ROP) is a form of chain-growth polymerization in which the terminus of a polymer chain attacks cyclic monomers to form a longer polymer (see figure).
The synthesis and processing of polyacetylene films affects the properties. Increasing the catalyst ratio creates thicker films with a greater draw ratio, allowing them to be stretched further. [8] Lower catalyst loadings leads to the formation of dark red gels, which can be converted to films by cutting and pressing between glass plates. [20]
The characterization of mechanical properties in polymers typically refers to a measure of the strength, elasticity, viscoelasticity, and anisotropy of a polymeric material. The mechanical properties of a polymer are strongly dependent upon the Van der Waals interactions of the polymer chains, and the ability of the chains to elongate and align ...