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Depolymerization is a very common process. Digestion of food involves depolymerization of macromolecules, such as proteins.It is relevant to polymer recycling.Sometimes the depolymerization is well behaved, and clean monomers can be reclaimed and reused for making new plastic.
Disadvantages of solution polymerization are decrease of monomer and initiator concentration leading to reduction of reaction rate, lower volume utilization of reactor, additional cost of the process related to solvent recycling, toxicity and other environmental impacts of most of organic solvents.
The light may be absorbed either directly by the reactant monomer (direct photopolymerization), or else by a photosensitizer which absorbs the light and then transfers energy to the monomer. In general, only the initiation step differs from that of the ordinary thermal polymerization of the same monomer; subsequent propagation, termination, and ...
In polymer science, dispersion polymerization is a heterogeneous polymerization process carried out in the presence of a polymeric stabilizer in the reaction medium. . Dispersion polymerization is a type of precipitation polymerization, meaning the solvent selected as the reaction medium is a good solvent for the monomer and the initiator, but is a non-solvent for the po
The degree of polymerization, or DP, is the number of monomeric units in a macromolecule or polymer or oligomer molecule. [1] [2] [3]For a homopolymer, there is only one type of monomeric unit and the number-average degree of polymerization is given by ¯ ¯ = ¯, where ¯ is the number-average molecular weight and is the molecular weight of the monomer unit.
Usage of monomer in the reaction: Rapid loss of monomer early in the reaction: Some monomer remains even at long reaction times Reaction steps: Similar steps repeated throughout reaction process: Different steps operate at different stages of mechanism (i.e. initiation, propagation, termination, and chain transfer) Average molecular weight
Fast and complete initiation of the monomer. This means that the rate at which an initiating agent activates the monomer for polymerization, must happen very quickly. How many monomers make up each polymer (the degree of polymerization) must be related linearly to the amount of monomer you started with. The dispersity of the polymer must be < 1 ...
In polymer chemistry, suspension polymerization is a heterogeneous radical polymerization process that uses mechanical agitation to mix a monomer or mixture of monomers in a liquid phase, such as water, while the monomers polymerize, forming spheres of polymer. [2] The monomer droplets (size of the order 10-1000 μm) are suspended in the liquid ...