Mechanically Robust Foamed Polypropylene/Bamboo Powder Composite Basketworks by CO₂ Extrusion Foaming

Abstract

Porous weave composites are some of the most important materials in our daily life because of their lightweight, high formability, sound and thermal insulation performance, etc. Unfortunately, the introduction of cellular structures will inevitably sacrifice the mechanical properties of porous materials. Here, we proposed a facile method to prepare mechanically robust foamed polypropylene (PP)/bamboo powder (BP) composite basketworks with sandwich structures (like cellular–solid–cellular structures) by extruding–foaming–weaving procedures. Here, the cellular structures on both sides provided weight reduction, softness, and heat insulation, while the solid part in the center improved the modulus and stiffness of the materials. Also, the evolution mechanism of the sandwich structures was revealed. Moreover, the relationship among the microstructure, thermal insulation, and mechanical thermal properties of the foamed basketworks was studied. For example, the elongation at break and specific modulus can increase from 23.6% and 124 MPa·cm3/g for PP/BP 1 to 53.3% and 350 MPa·cm3/g for PP/BP 4, respectively. Sandwich structures also provide much better thermal insulation than solid structures. Furthermore, the foamed fabrics with different colors were woven into basketworks, which can be used in placemats, decorative belts, baskets, and other fields.