Nah, tripping and disarming is inherent of each and every chain weapon. Flails and spiked chains and gyrspikes.

Try this. 10ft range, but -2 penalty for attacking adjacent foes (because you have no spikes to help you and the momentum of the chain does most of the damage when not adjacent to a target).

1d6 damage.

This reminds me of the Duom, a spear that one could use with a back thrust at a -2 penalty. Exotic 1d8 but it did to x3 damage on criticals.