An ideal dilution estimate for a random copolymer whose comonomer units are excluded from the crystal. Let be the crystallizable-unit fraction in the melt and the molar enthalpy of fusion per such unit. Mixing contributes to its liquid chemical potential. Approximate the unmixed liquid-minus-solid chemical-potential difference by . Equating the sum to zero gives the displayed relation. For , the predicted melting temperature decreases. Nonideal mixing, finite crystallizable sequences, lamellar surface energy and comonomer inclusion can change the result.
A copolymer containing and units. It describes the intended chemical composition, not a guarantee that unselective alkaline treatment yields an undegraded polymer.
A copolymer containing and units. Hydrolysis changes the acetate side groups without requiring cleavage of the carbon backbone, provided competing degradation is controlled.
Alkaline conditions that hydrolyse acetate side groups can also promote elimination from chlorinated backbone units. Dechlorination, unsaturation, changed solubility and possible subsequent cross-linking complicate isolation of an ideal vinyl chloride-vinyl alcohol copolymer. The competition is condition-dependent: analytical work used staged treatment and precipitation to restrain dehydrochlorination, so difficulty under generic conditions is not a proof that every hydroxyl-containing chloride copolymer is impossible.[ref]
Determination of vinyl acetate in vinyl chloride-acetate copolymers by Takanori Shimazaki and others. Abstract and pp. 619–623: staged treatment, polymer precipitation and suppressed dehydrochlorination
A copolymer with an ideal sequence in which the probability of a monomeric unit is independent of neighbouring units. A real copolymer made by concurrent radical reactions can have sequence correlations; a feed ratio does not by itself establish incorporated composition or independent-unit statistics.
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A copolymer is a type of polymer that is made from two or more different monomers (the building blocks of polymers) rather than just one type. The different monomers can be arranged in various ways, leading to different structures and properties in the resulting copolymer. The arrangement can be random, alternating, block, or grafted, among other configurations.