Ground tire rubber (GTR) was treated by microwaves
at the same power and at different times of exposure, in order to improve
their recycling characteristics. The resulting materials were characterized
by thermogravimetric analysis (TG/DTG) and differential scanning calorimetry
(DSC). DSC analysis showed that the microwaves treatment, specially for longer
exposure times, changes the thermal behavior at low temperatures, that is
to say, changing its glass transition (Tg),
probably due to the modification in the chemical structure of the rubber.
The TG/DTG analysis showed that the thermo-oxidation behavior of the sample
after the microwaves treatment is different from the sample before the treatment.
The thermo-oxidation temperature of the devulcanized rubber is shifted to
lower temperatures, even for the rubber treated in short times.