Post-transfer phenomena

Post-polymerization fimctionalization has been used to this end, but most research has been directed toward the copolymerization of ethylene with polar monomers. In this manner, inexpensive monomers can be used to create novel polymeric materials with a wide range of applications. The major drawback to this methodology is the inherent difference in reactivity between ethylene and other vinyl monomers during chain polymerization. This phenomenon is known to yield copolymers with low polar monomer incorporation and increased branch content arising from chain transfer events caused by side reactions with polar and/or protic functionaUties [45]. 

More recent research studies on the heat transfer deterioration have revealed the following characteristics. Generally, the heat transfer deterioration phenomenon occurs only around the critical point (for water, the critical point is at 374.2°C and 22.1 MPa) or the pseudocritical temperature. The mechanisms of the heat transfer deterioration differ from those of the boiling crises of the subcritical pressure. Compared with the boiling crisis, the temperature rise of the heated surface wall is milder. The post deterioration heat transfer rate can be predicted by numerical analyses based on turbulence models and the occurrence of the heat transfer deterioration can be suppressed by promoting the turbulence. 

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