Effect of Replacing Carbon Black with Surfactant-Modified Natural Feldspar on Mechanical Properties of Natural Rubber Composites

摘要

The effect of replacing carbon black (CB) with surfactant-modified natural feldspar (SMNF) on hardness and tensile properties of natural rubber (NR) composites was studied using a simplex-lattice mixture design of experiment. SMNF was produced by treating natural feldspar (NF) with coconut diethanolamine (CDEA) and glycerol monostearate (GMS). Complete replacement of CB with SMNF based from CDEA or GMS decreased Shore A hardness and tensile stress at all elongations. NR composites reinforced with SMNF based from GMS exhibited higher mechanical properties than from CDEA which is attributed to the higher hydrophobicity factor of GMS. CDEA may also have aggregated on the surface of NF, resulting to poor filler dispersion and ineffective stress transfer.