225Eco-Friendly Fiber-Reinforced Natural Rubber Green Composites
It is reported that on increasing the ber loading, the optimum cure time remains
almost constant. This trend is observed for the mixes containing both acetylated and
untreated ber. In the presence of bonding agent, the optimum cure time is lower for
mixes containing acetylated ber when compared with that of compounds contain-
ing untreated ber at the same loading. They have investigated the effect of different
bonding agents on the physical and mechanical properties of sisal ber–reinforced
NR composites. The treatments employed included alkali immersion at high tem-
perature and the use of bonding agent based on phenol-formaldehyde or resorcinol
formaldehyde, hexamethylenetetra ...