I dont really know as I am not really an expert at how the powder toy is coded. It soudns interesting though.
I posted a similar topic about being able to pressurize liquids and gases, but I didn't include all of these details. I was thinking that maybe the particles could act like BOYL, as in if they were in close proximity, they would create pressure. I realized that this would break a lot of saves, so I posted that changing a gas or liquid's CYTPE to BOYL would be an alternative solution.