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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.
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 simplest case refers to the formation of a strictly linear polymer by the reaction (usually by condensation) of two monomers in equimolar quantities. An example is the synthesis of nylon-6,6 whose formula is [−NH−(CH 2) 6 −NH−CO−(CH 2) 4 −CO−] n from one mole of hexamethylenediamine, H 2 N(CH 2) 6 NH 2, and one mole of adipic acid, HOOC−(CH 2) 4 −COOH.
Another possibility is chain transfer to a second polymer molecule, result in the formation of a product macromolecule with a branched structure. In this case the growing chain takes an atom X from a second polymer chain whose growth had been completed. The growth of the first polymer chain is completed by the transfer of atom X.
Specific materials and their applications include polymer-protein and polymer-drug conjugates, mediation of enzyme activity, molecular recognition processes and polymeric micelles which can deliver a drug to a specific site in the body. [19] RAFT has also been used to graft polymer chains onto polymeric surfaces, for example, polymeric ...
Radical polymerization is a key synthesis route for obtaining a wide variety of different polymers and materials composites. The relatively non-specific nature of radical chemical interactions makes this one of the most versatile forms of polymerization available and allows facile reactions of polymeric radical chain ends and other chemicals or ...
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 ...
Poly(p-phenylene vinylene) (PPV, or polyphenylene vinylene) is a conducting polymer of the rigid-rod polymer family. PPV is the only polymer of this type that can be processed into a highly ordered crystalline thin film. PPV and its derivatives are electrically conducting upon doping.