Hello

My first post. I have two metal frame chairs that came with those woven vinyl straps for the seat and back. My problem is those vinyl straps have broken and they are factory sealed to the frame. I would like to repaint the frame and weave a new seat and back, but am unsure what material would hold up best outside and where to find materials. My vision is to weave and knot, maybe some type of poly rope? Something that won't stretch too much if it gets hot, from sun, and that sunlight won't destroy too quickly. I would appreciate any and all help with this. Thanks to you all.