Is used to get suspensions thru a 25g pin or smaller, it stops clogging for a smoother injection 2-3% poly80 is used.
Basicly stops the suspension sticking together and forming bigger clumps, sort of a lubricant.
There's studies on a lot of solvents etc that's used in homebrews to say there bad, if you want a certain aas then you use what you need to.