Biodegradable composites based on poly(butylene adipate‐co‐terephthalate) (PBAT) and three different natural fibers (Croton lanjouwensis—Fiber C, Malvastrum tomentosum—Fiber M, and Trema micrantha—Fiber T) from the Amazon forest have been reported for the first time. Natural fibers were extracted through mechanical processing and the composites were prepared by melt mixing procedure. All composites showed greater modulus of elasticity than neat polymer and this improvement varies according to the type of fiber used as reinforcement. Addition of Fiber C increased 48% the modulus of elasticity of the polymer, while the addition of the Fibers M and T increased 70 and 72% the modulus of elasticity of the PBAT, respectively. The results reported in the present work support the idea that the above‐mentioned natural fibers can be used as filler material to obtain environmentally friendly polymer composites with improved properties. POLYM. COMPOS., 40:3351–3360, 2019. © 2019 Society of Plastics Engineers

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The natural fiber market has been growing extraordinarily. Hereupon the current work presents the natural fiber of the periquiteira tree Cochlospermum orinocense of the Amazon forest. The chemical composition, physical aspects, morphology, thermal and mechanical properties of this fiber will be discussed. The thermal stability of the fiber samples was about 200 °C. The decomposition of cellulose and hemicelluloses in the fibers occurred at 300 ºC and above, while the degradation of the fibers happened above 400 °C. This fiber had good specific strength and good binding properties due to their low weight and presence of high cellulose (60.15wt.%), low lignin (12.03wt.%). More pronounced mass loss indicated the degradation of the amorphous regions of the cellulose, and finally reached a peak of approximately 390 °C.

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The present work aims at the preliminary evaluation of the Paspalun repens macrophyte dry biomass adsorbent material of zinc (Zn) and copper (Cu) metals from water. The diversity of Species is due to the extensive aquatic environment where it is inserted. The Paspalun repens species comes from the Buiuçu lake located in the region of Parintins-Amazonas-Brazil. The macrophyte was dried in a mill and then a digestion through biomass microwaves was done before and after its exposure to the solutions containing different concentrations of zinc and copper (1.00, 1.50, 2.00, 3.00 mg mL -1 of metals) for a period of 48 hours. As a source of the metals, zinc sulfate (ZnSO 4 7H 2 O) for zinc, and copper sulfate (CuSO 4 5H 2 O) for copper were used as the source. As a result, the efficiency of Paspalun repens was observed in the metals removal, the highest removal percentage, of 29.67 and 37.07% in the leaves, whereas in the root it was 25.25 and 32.84% (at the concentration 1.0 and 2.0 mg/mL consequently), was of zinc, therefore the dry biomass of this species can be considered as a low cost alternative material in the removal of these heavy metals, contributing to the improvement of water quality.