China would collapse in all ways possible. Everything built and established for the last 30 years is completely dependent on rising export to west, to the point where China is already cooking the book with fake-shipments.
The only thing China can do is to continue lending money to USA and Europe to keep us propped up and buying their goods.
Everything is planed out this way since after WWII, keep nations dependent on each other for survival, hence less chance for WWIII.
Looks like tremendous success so far!
Economic collapse is almost impossible, save for a cataclysmic events of some sort. All in all very unlikely.