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  2. Step-growth polymerization - Wikipedia

    en.wikipedia.org/wiki/Step-growth_polymerization

    The distinction between "step-growth polymerization" and "chain-growth polymerization" was introduced by Paul Flory in 1953, and refers to the reaction mechanisms, respectively: [4] by functional groups (step-growth polymerization) by free-radical or ion (chain-growth polymerization)

  3. Carothers equation - Wikipedia

    en.wikipedia.org/wiki/Carothers_equation

    This is true for step-growth polymerization of linear polymers. For chain-growth polymerization or for branched polymers, the Đ can be much higher. In practice the average length of the polymer chain is limited by such things as the purity of the reactants, the absence of any side reactions (i.e. high yield), and the viscosity of the medium.

  4. Flory–Stockmayer theory - Wikipedia

    en.wikipedia.org/wiki/Flory–Stockmayer_theory

    The Flory–Stockmayer Theory allows for the prediction of when gelation occurs using percent conversion of initial monomer and is not confined to cases of stoichiometric balance. Additionally, the Flory–Stockmayer Theory can be used to predict whether gelation is possible through analyzing the limiting reagent of the step-growth polymerization.

  5. Wallace Carothers - Wikipedia

    en.wikipedia.org/wiki/Wallace_Carothers

    Carothers worked out the theory of step-growth polymerization and derived the Carothers equation which relates the average degree of polymerization to the fractional conversion (or yield) of monomer into polymer. This equation shows that for a high molecular weight, a very high fractional conversion is needed (for step-growth polymers only).

  6. Polymerization - Wikipedia

    en.wikipedia.org/wiki/Polymerization

    Step-growth polymers increase in molecular weight at a very slow rate at lower conversions and reach moderately high molecular weights only at very high conversion (i.e., >95%). Solid state polymerization to afford polyamides (e.g., nylons) is an example of step-growth polymerization. [8]

  7. Acyclic diene metathesis - Wikipedia

    en.wikipedia.org/wiki/Acyclic_diene_metathesis

    ADMET is a type of step-growth, condensation polymerization. It should be distinguished from ring-opening metathesis polymerization (ROMP), which is a chain-growth, addition polymerization. [1] Whereas ADMET is driven by the release of volatile ethylene gas, ROMP is driven by the relief of ring-strain.

  8. Nylon rope trick - Wikipedia

    en.wikipedia.org/wiki/Nylon_Rope_Trick

    Acid Chloride Preparative Route for Nylon-6,10, which is often used in the nylon rope trick. The nylon rope trick is a scientific demonstration that illustrates some of the fundamental chemical principles of step-growth polymerization and provides students and other observers with a hands-on demonstration of the preparation of a synthetic polymer.

  9. Supramolecular polymer - Wikipedia

    en.wikipedia.org/wiki/Supramolecular_polymer

    In conventional covalent polymerization, two models based on step-growth and chain-growth mechanisms are operative. Nowadays, a similar subdivision is acceptable for supramolecular polymerization; isodesmic also known as equal-K model (step-growth mechanism) and cooperative or nucleation-elongation model (chain-growth mechanism).