Alkanolamide (ALK) and Aminopropyltriethoxy Silane (APTES) were incorporated separately
into silica-filled SMR-L compounds at 1.0, 3.0, 5.0 and 7.0 phr. It was found that compounds
with both ALK and APTES exhibited cure enhancement, better filler dispersion and greater
rubber-filler interaction. Both additives also produced modulus and tensile enhancements in
the silica-filled SMR-L compounds, especially up to a 5.0 phr loading. At a similar loading,
ALK exhibited higher reinforcing efficiency of silica than APTES.