Generally, the tensile strength of PP will decrease with
the addition of natural rubber, as immiscible and the
mismatch between the polymer, it can be improved by
the addition of a suitable compatibilizer so that adhesion
between the two materials can be improved [9].
Addition of PP-g-MA increases the interaction between
natural rubber and PP, improve adhesion and spread the
filler system that is hydrophilic and hydrophobic matrix
[10] and can increase and decrease the size of the phase
homogeneity of natural rubber which are distributed so
that the tensile strength increases [11]. The increase is
also due to the tensile strength of adhesion derived from
PP-g-MA which can react with the hydroxyl group
(OH) on thermoset materials