In this research study the effect of adding thermal cement as a filler on the properties
of natural rubber STR20, through the preparation of natural rubber mixtures containing
different ratios of thermal cement (0,5,10,15,20 pphr) on the rolling ru
bber machine, then
characterization physico-mechanical properties and chemical of mixtures that prepared
and then tested to measure the tensile strength, resistance friction and determine the
hardness and swelling values in different solvents.
The results showed increased tensile strength with increased thermal cement ratio
until
15( pphr) but after this percentage take tensile strength to decline gradually, where
the relationship becomes counterproductive between the additives and the resistance ratio,
as noted the low percentage of elongation at break gradually with increasing the proportion
of thermal cement, as for the hardness values it has increased in extrusive with increase
the proportion of thermal cement in mixtures, also observed a decrease in friction
resistance with increase the additives proportion even (15 pphr) to rise after that.
Results of the study also showed that the samples swelling in mineral oil was lower
compared to all of the gasoline and diesel, the swelling was in the mineral oil 1.29%, while
in gasoline was 14.15% and in diesel was 12.43%.
