Not recommended. Plexiglass will break in a car window application too. If you want a non-glass material for your window, you’re looking for lexan, which is what they use in race cars.
But the problem with lexan is that it scratches easily, so you have to put a protective film over both sides, and of course as soon as you scrape snow off of it (because you no longer have a rear defroster) you will scratch and/or destroy the film, scratch the lexan, and have to start all over.
Or in short, just replace the glass.