No. It will not work as a master off-camera. None of the Canon flashes can be used simultaneously as a slave and a master. The 90EX is only a master unit if used on the hotshoe, or tethered off-camera with a TTL cable. If used on manual-only radio triggers, there's no way for it to sense it should perform master communication. And TTL radio triggers act as a master, and treat all attached flashes as slaves.
If you are using a 600D, 60D, or 7D or later body, you already have a master built into your pop-up flash. The simplest way to trigger a 430EXII would be to use that. If, however, you don't have this capability, other methods would include using a PC sync cable or add-on "dumb" optical slaves (which may require hotshoe adapters for either/both your camera and flash), a TTL cable, or radio triggers. The most cost-effective and popular solution would probably be to get manual-only radio triggers. They can be found in the US$25-40 price range for a Tx/Rx or transceiver pair. This will only communicate the "fire" signal. You won't have HSS, TTL, or any remote control over the camera (the flash control menu on the camera will be grayed out). But you can fire the flash remotely, and the 430EXII has M mode, so you can set power explicitly on the flash itself.
See also: What should I look for in a wireless flash trigger for a home studio?