Recyclability of cellulose acetate butyrate (CAB) matrix for controllable and productive fabrication of thermoplastic nanofibers

A high-throughput, controllable and environmentally benign fabrication process of thermoplastic nanofibers with a biobased material, cellulose acetate butyrate (CAB) as the matrix was recently reported. To prove the recyclability of the CAB, a method was proposed to theoretically demonstrate the ability of the recycled polymer for repeated melt extrusions based on a comparison of thermal degradation and flow activation energy of the recycled polymers. The flow activation energy was derived from rheological behaviors of the original and recycled CAB at different temperatures. The thermogravimetric analysis (TGA) was utilized to characterize the thermal degradation behaviors of the polymer. The change in the number average molecular weight of the recycled CAB was studied by measuring the intrinsic viscosity and the Mark-Houwink equation. To display the practical recyclability, the recycled CAB was successfully employed to serve as the matrix for the preparation of iPP (polypropylene), PTT (poly trimethylene terephthalate) and PE-co-GMA (poly (ethylene-co-glycidyl methacrylate)) nanofibers. The proposed quantitative method could be extended to evaluate the recyclability of the other thermoplastics.