Impermax is a DeFi lending platform that lets Uniswap liquidity providers use their LP tokens as collateral for permissionless loans. This potentially unlocks billions of dollars locked in LP token contracts that are otherwise unusable.
These LP token backed loans can be used for trading, staking, or other purposes, but the most interesting case is to use loans to increase one's liquidity providing position. This allows yield farmers to multiply returns many times without adding any additional funds of their own. This is called leveraged yield farming, and it's what Impermax is designed for. A leveraged yield farmer can multiply their Uniswap yields up to 20 times, (although leverage comes with increased risk of impermanant loss.)
IMX token holders control governance, profits, and reserves generated by interest and fees on the Impermax lending platform.