title: Nano- and macroscale structural and mechanical properties of in situ synthesized bacterial cellulose/PEO-b-PPO-b-PEO biocomposites.
abstract: Highly transparent biocomposite based on bacterial cellulose (BC) mat modified with poly(ethylene oxide-b-propylene oxide-b-ethylene oxide) block copolymer (EPE) were fabricated in situ during biosynthesis of bacterial cellulose in a static culture from Gluconacetobacter xylinum. The effect of the addition to the culture medium of water-soluble EPE block copolymer on structure, morphology, crystallinity, and final properties of the novel biocomposites was investigated at nano- and macroscale. High compatibility between components was confirmed by ATR-FTIR indicating hydrogen bond formation between the OH group of BC and the PEO block of EPE block copolymer. Structural properties of EPE/BC biocomposites showed a strong effect of EPE block copolymer on the morphology of the BC mats. Thus, the increase of the EPE block copolymer content lead to the generation of spherulites of PEO block, clearly visualized using AFM and MO technique, changing crystallinity of the final EPE/BC biocomposites investigated by XRD. Generally, EPE/BC biocomposites maintain thermal stability and mechanical properties of the BC mat being 1 wt % EPE/BC biocomposite material with the best properties. Biosynthesis of EPE/BC composites open new strategy to the utilization of water-soluble block copolymers in the preparation of BC mat based biocomposites with tunable properties.
authors: Group 'Materials + Technologies' (GMT), Department of Chemical and Environmental Engineering, Polytechnic School, University of the Basque Country (UPV/EHU) , Plaza Europa 1, 20018 Donostia-SanSebastián, Spain.
authors: Agnieszka
authors: A
authors: Tercjak
authors: Junkal
authors: J
authors: Gutierrez
authors: Hernane S
authors: HS
authors: Barud
authors: Rafael R
authors: RR
authors: Domeneguetti
authors: Sidney J L
authors: SJ
authors: Ribeiro
mesh_terms: D001696:Biomechanical Phenomena; D001704:Biopolymers / Q000096:biosynthesis* / Q000737:chemistry; D002482:Cellulose / Q000096:biosynthesis* / Q000737:chemistry; D003470:Culture Media / Q000737:chemistry / Q000378:metabolism; D041822:Gluconacetobacter xylinus / Q000737:chemistry / Q000378:metabolism*; D018625:Microscopy, Atomic Force; D053761:Nanocomposites / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry / Q000378:metabolism*; D011409:Propylene Glycols / Q000737:chemistry / Q000378:metabolism*; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D001704:Biopolymers; D003470:Culture Media; C116176:PEO-PPO-PEO; D011409:Propylene Glycols; D011092:Polyethylene Glycols; D002482:Cellulose
keywords: atomic force microscopy; bacterial cellulose; biocomposites; block copolymer; mechanical properties