Thermally Processable, Transparent, Mechanically Tunable and Robust Bioplastics From Wastepaper

ABSTRACT To mitigate the environmental impact of plastic pollution and paper waste, developing bioplastics from wastepaper as alternatives to non‐degradable petroleum‐based plastics is of great importance. However, current wastepaper recycling faces challenges such as complex preparation processes, low efficiency, suboptimal performance, and limited scalability. In this work, we present a facile and scalable direct hot‐press transformation approach to directly convert wastepaper into thermally processable, transparent, and high‐performance bioplastics. This approach involves the cleavage of the cellulose ring structure in wastepaper, followed by hot‐pressing under mild conditions. The resultant bioplastics demonstrate excellent thermal processability and tunable mechanical properties (with tensile strengths ranging from 85.7 to 103.2 MPa) and thus can be converted into rigid containers or flexible packaging bags without the need for adhesives. They also exhibit high optical transparency, good water resistance, repairability and biodegradability. This work provides a streamlined direct transformation strategy to produce thermally processible, transparent and mechanically robust bioplastics, offering a scalable avenue to transform waste papers into bioplastics for sustainable packaging.