Abstract
Abstract Eco-friendly and sustainable tape casting of alumina powder suspensions using concentrated natural rubber (poly isoprene) latex binder has been studied. The high negative zeta potential values of the aqueous alumina slurry (−53 to −72 mV) and rubber latex (−67 to −84 mV) at pH in the range of 9–11.5 enables their co-dispersion to produce tape casting slurries of solids (alumina + rubber) concentration >60 vol% with adequate flow characteristics. Drying of the slurry tape-cast on Mylar substrate is achieved within 15 min at 70 °C due to its high solid concentration. The green tapes containing 14.2 to 18.1 wt% of rubber shows tensile strength and strain at failure in the ranges of 1.85 to 1.61 and 41–254%, respectively. The flexible green tapes turn rigid by annealing at 200 °C due to the self-cross-linking of rubber chains induced by the Lewis acid sites of alumina. Thickness reduction to the extent of 20% by rolling of the green tape before annealing improves the green microstructure which results in an enhancement in sintered density from 93 to 98% of the theoretical value. However, the additional rolling and annealing steps consume extra time and energy compared to the tape casting processes using other reported binders.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
