Depends what you mean. If you mean the stuff that is really fairly stiff, I believe it is actually sold as plastic hardwarecloth, that will keep chickens in pretty well. If OTOH you mean the very flimsy stuff that is essentially glorified garden netting, it is all floppy like fabric and the strands are not a whole lot thicker than fishing-line, it is not chickenproof if chickens wish to go thru it. In fact there's a thread within the past 24 hrs or so in which someone describes their chickens repeatedly ripping holes in that and getting out.
Nothing that is all-plastic is even remotely predatorproof. (Well, some are reasonably hawk-proof, but I mean not 4-legged predator proof)
Good luck, have fun,
Pat