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  2. Reversible addition−fragmentation chain-transfer polymerization

    en.wikipedia.org/wiki/Reversible_addition%E2%88...

    Such a polymerization, is referred to as a rate-retarded RAFT polymerization. The rate of a RAFT polymerization, that is, the rate of conversion of monomer into polymer, mainly depends on the rate of the Propagation reaction (Figure 5) because the rate of initiation and termination are much higher than the rate of propagation.

  3. Polymer soil stabilization - Wikipedia

    en.wikipedia.org/wiki/Polymer_soil_stabilization

    Synthetic polymers began replacing other chemical binders for soil stabilization in agriculture in the late 20th century. [1] Compared to traditional chemical binders, polymer soil additives can achieve the same amount of strengthening at much lower concentrations – for example, mixtures of 0.5-1% of various biopolymers have strength levels that match or exceed those of 10% cement mixtures ...

  4. Poly(4-vinylphenol) - Wikipedia

    en.wikipedia.org/wiki/Poly(4-vinylphenol)

    PVP is typically prepared by free radical polymerization of 4-vinylphenol or a protected form of 4-vinylphenol. [1] The protected monomers can be prepared from 4-hydroxybenzaldehyde, by vinylation of phenols, or acylation of polystyrene followed by oxidation at room temperature.

  5. Living free-radical polymerization - Wikipedia

    en.wikipedia.org/wiki/Living_free-radical...

    The CTA for RAFT polymerization must be chosen cautiously because it has an effect on polymer length, chemical composition, rate of the reaction and the number of side reactions that may occur. The mechanism of RAFT begins with a standard initiation step as homolytic bond cleavage of the initiator molecule yields a reactive free radical.

  6. End group - Wikipedia

    en.wikipedia.org/wiki/End_group

    RAFT polymerization mechanism. Another method of end group removal for the thiocarbonyl containing end-groups of RAFT polymers is the addition of heat to the polymer; this is referred to as thermolysis. One method of monitoring thermolysis of RAFT polymers is by thermogravimetric analysis resulting in a weight-loss of the end group.

  7. Chain transfer - Wikipedia

    en.wikipedia.org/wiki/Chain_transfer

    In polymer chemistry, chain transfer is a polymerization reaction by which the activity of a growing polymer chain is transferred to another molecule: [1] [2] + + where • is the active center, P is the initial polymer chain, X is the end group, and R is the substituent to which the active center is transferred.

  8. Russia detains Uzbek national over bomb assassination of ...

    www.aol.com/russia-detains-uzbek-national-over...

    A day before his killing, the SBU said that, on Kirillov’s orders, Russia had used more than 4,800 cases of chemical munitions since the war began.

  9. Living polymerization - Wikipedia

    en.wikipedia.org/wiki/Living_polymerization

    Living polymerization: A chain polymerization from which chain transfer and chain termination are absent. Note: In many cases, the rate of chain initiation is fast compared with the rate of chain propagation, so that the number of kinetic-chain carriers is essentially constant throughout the polymerization. [3]