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Ceiling temperature exothermic addition polymerization

Poly(2-methyl-1-pentene sulfone) (PMPS) is an alternating copolymer of 2-methyl-l-pentene (2MP) and sulfur dioxide. The formation of PMPS occurs only by a free radical polymerization mechanism and is complicated to a degree by ceiling temperature considerations. For all exothermic addition polymerization reactions there is a critical temperature called the ceiling temperature (Tc) above which no reaction occurs. The precise Tc depends upon the monomer concentration according to the expression (i)... [Pg.125]

For vinyl addition and diene polymerizations, heat removal is a primary concern. The reaction exotherm listed in Table 1 is the heat of polymerization divided by the specific heat of the polymer. It is a fictitious quantity for energetic polymerizations since bonds break and the polymer reaches a ceiling temperature well before... [Pg.850]

As in any exothermic reaction, the preference for the products will be diminished at higher temperature. In the case of most addition polymerization reactions, there will be a temperature above which no further polymerization can occur. This temperature is called the ceiling temperature and is always associated with a specific monomer concentration [M] through eqn [11], which relates the enthalpy and entropy of polymerization calculated for some standard state concentration of monomer. [Pg.37]

Most addition polymerization reactions are exothermic and exentropic. The free energy of polymerization per monomer unit therefore becomes less negative as the temperature is raised. At the ceiling tmperatm T, free energy of polymerization under the prevailing conditions is zero, and above... [Pg.427]


See other pages where Ceiling temperature exothermic addition polymerization is mentioned: [Pg.8452]    [Pg.1220]    [Pg.132]    [Pg.62]   
See also in sourсe #XX -- [ Pg.125 ]




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Addition polymerization

Addition temperature

Additional polymerization

Additives polymerization

Ceilings

Exothermic polymerization

Exothermic, exothermal

Exothermicity

Exotherms

Polymeric additives

Polymerization exothermicity

Polymerization temperature

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