Are there high-speed video cameras that use shutter speeds lower than microseconds?

I've been interested in high-speed photography. My equipment is limited: I use a DSLR camera and custom shots with a very short xenon flash to take pictures of things like bursting balloons. (I open the shutter in complete darkness before the balloon explodes, and I use the flash discharge to freeze the movement).

From what I've read, the edges of an emerging balloon move faster than the speed of sound. Despite my best efforts, the edges of my bulging balloons are always blurred. According to my research, it seems that the fastest discharge I can get from a xenon flash is around 1 / 40,000 of a second. It seems that you need to get exposures less than a microsecond to get sharp images of supersonic motion.

Sometimes I put cornstarch on the balloons and I get some fascinating patterns in the cornstarch: enter the description of the image here

I really need a flash of air space to get clear images. Sparkles of air space create bright discharges as fast as 1/2 microseconds. (1 / 2,000,000 of a second.)

However, what I really want to do is understand how those patterns are formed in the cornstarch as the balloon appears. To do that, I need a high-speed video camera that takes images with shutter speeds lower than microseconds, and very quickly. Are there high-speed commercial cameras that can do that and that can be rented by mere mortals? And how could I pump enough light on my subject to expose those extremely short shutter speed images?

I know that Dr. Edgerton used moving movies and rotating mirrors to create images in a microsecond of exploding atomic bombs, but those cameras weighed hundreds of pounds and cost hundreds of thousands of dollars, or maybe more.