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Polymerization of ethylene. Diverse methods are employed to manipulate the initiation, propagation, and termination rates during chain polymerization. A related issue is temperature control, also called heat management, during these reactions, which are often highly exothermic. For example, for the polymerization of ethylene, 93.6 kJ of energy ...
Solution polymerization is a method of industrial polymerization. In this procedure, a monomer is dissolved in a non-reactive solvent that contains a catalyst or initiator . The reaction results in a polymer which is also soluble in the chosen solvent.
The polymerization is obtained with a broad molecular weight distribution due to the high viscosity and lack of good heat transfer. very high molecular weights are obtained. Gel effect. For reducing the disadvantages of bulk polymerization, the process can be carried out in a solution. This is known as solution polymerization. [2]
Initiation is the first step of the polymerization process. During initiation, an active center is created from which a polymer chain is generated. Not all monomers are susceptible to all types of initiators. Radical initiation works best on the carbon–carbon double bond of vinyl monomers and the carbon–oxygen double bond in aldehydes and ...
However in step-growth polymerization the monomer is consumed very quickly to dimer, trimer and oligomer. The degree of polymerization increases steadily during the whole polymerization process. The type of polymerization of a given monomer usually depends on the functional groups present, and sometimes also on whether the monomer is linear or ...
Curing is a chemical process employed in polymer chemistry and process engineering that produces the toughening or hardening of a polymer material by cross-linking of polymer chains. [1] Even if it is strongly associated with the production of thermosetting polymers , the term "curing" can be used for all the processes where a solid product is ...
Since the polymerization happens in the crystalline lattice without the aid of solvents or reagents, it comes under the domain of green chemistry. [18] Also, the topochemical polymerizations are mostly atom economical reactions. The product can be obtained without any further purifications.
A classification of the polymerization reactions. Polymerization is the process of combining many small molecules known as monomers into a covalently bonded chain or network. During the polymerization process, some chemical groups may be lost from each monomer. This happens in the polymerization of PET polyester.