| 摘要 |
The process for the polymerization in aqueous dispersion of tetrafluoroethylene in the presence of an emulsifier and an initiator, with the latter yielding free radicals between 0 DEG and 45 DEG C. and being destroyed for a temperature above 45 DEG C., characterized by the fact that the temperature of the reaction medium as a function of polymerization time is made to follow an ascending curve, Temperature DEG C. versus t (time in minutes) whose slope ( DELTA T/ DELTA t) cannot be less than 1/6, DELTA T representing the temperature in DEG C. at a given time in minutes DELTA t, with this ascending curve being situated inside of a sector limited by two straight lines y=(7/12)x and y=(15/7)x+45, in which y and x respectively represent the temperature in DEG C. and the time expressed in minutes, and by the fact that the initiator is destroyed before the concentration of polytetrafluoroethylene in the dispersion has reached 20%.
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