The best approaches to minimizing resource scarcity, removing valuable waste streams, and re-establishing a circular economic chain of recycled thermoplastics are to cascade them into product life cycles and their valorization combined with sustainable raw materials. As one part of this goal, WPC was formulated from three recycled PE plastic wastes: linear low-density polyethylene (LLDPE), medium-density polyethylene (MDPE), high-density polyethylene (HDPE), and underutilized EHB. The chemical composition of EHD, chemical structure, crystallinity, melting and crystallization points, residual metal additives, and polycyclic aromatic hydrocarbons (PAHs) of recycled PE were investigated using standard chromatographic and spectroscopic methods such as HPAEC-UV/VIS, FTIR, DSC, GC/MSD, and XPS. The properties of WPC formulations from different compositions of bamboo particles (BP) as dispersed phase, individual recycled PE plastics, and equal melt blend (EM) as polymer matrix were investigated extensively and measured with a known standard. These comprised tensile strength (TS), modulus of elasticity (TM), flexural strength (FS), modulus of rupture (FM), and unnotched impact strength (UIS). It also included the effect of various alkaline surface treatment ranges on the interface surface interaction. The results show improved mechanical properties for all blending ratios of surface-treated BP, which resulted from better encapsulation in the polymer matrix. Despite its inherent immiscibility, WPC formulation from equal melt blending revealed unusual properties compared to separate phase blends, which is attributed to thermally induced cross-linking. This implies that melt blending of the weakest and cheapest recycled LLDPE with relatively cheap recycled MDPE and HDPE improves the properties of the blend, particularly toughness, while simultaneously retaining some of their properties.

A resource balance comprises a method to monitor sources and uses of a given material. The wood resource balance analyses origins of wood resources used in the production of semi finished forest products. At the same time, the resource balance helps tracking wood processing residues and its further uses. A primary survey with 113 companies was conducted and official statistics were consulted to carry out the first wood resource balance for Brazilian plantation forests. The balance sheets were analysed for 2008 and 2018. Wood resources consumption increased from 208 to 231 million m³. Wood processing residues volumes had grown by 19 % in the same period. Round wood demand for material use accounted to 66 % in 2018 whilst 99 % of residues were used energetically. The sector’s supply and production sides have shown to be in an exceptional balance. An increase on resource efficiency and cascading uses was observed in Brazil during the analysed period. The plantation forests supplied the greater domestic demand for round wood which relieves use pressure on natural forests.