Towards innovative bio-based transparent wood composite with high transmittance
Topic(s) : Multifunctional and smart composites
Co-authors :
Liya ANTONY (ITALY), Simone BRUNO , Antonella GIURI , Luisa DE MARCO (ITALY), Aurora RIZZO , Carola Esposito CORCIONE , Barbara CORTESE , Rosanna MASTRIAAbstract :
Wood is a biomass material with intrinsic properties, such as a porous structure, lightweight,
recyclability, biodegradability, and unique thermal and mechanical characteristics. Specifically, wood-based composites derived from natural wood exhibit significant potential for diverse applications, including building structures, packaging, and substrates for optoelectronic devices. Conventionally, transparent wood composites are developed in two steps. The wood is modified either through a delignification or bleaching process, followed by impregnating refractive index- matched polymers into the modified samples under vacuum. Paradoxically, current techniques for developing highly efficient transparent wood composites often involve the use of chemicals and petroleum-based polymers during fabrication, leading to adverse environmental effects. To address these challenges, this study aimed to develop a transparent wood bio-composite using non-toxic chemicals and bio-based resins. Non-toxic and volatile components, such as hydrogen peroxide (H2O2) and sodium hydroxide (NaOH), were utilized to modify the lignin content in balsa wood through a bleaching process. Subsequently, these bleached samples were impregnated with bio-based resin instead of petroleum-based resins. The study conducted a comparative analysis of the
performance of two types of bio-based epoxy resins (Polar Bear epoxy (PB-R) and Soya Resin (SG-30 R)) with synthetic epoxy resin (E-30-R). Generally, the transparency of the obtained composites is mainly influenced by the ratio of resin to hardener, curing conditions, and the duration of resin impregnation. The polymer infiltrates the porous structure of the balsa wood during infiltration, resulting in a transparent wood bio-composite. Optical, morphological, thermal, and mechanical studies were conducted using UV-Vis spectrophotometer, scanning electron microscope, differential scanning calorimeter, and a tensile testing machine, respectively. The soya resin- infiltrated transparent wood composite exhibited a combination of better optical transparency (83% at 550 nm), high haze (85%), ultraviolet-blocking efficiency, and hydrophobic nature compared to other composites. Furthermore, the use of bio-based materials (wood and bio-based resin) has a lesser environmental impact, making the developed composite a promising and environmentally friendly material for further exploitation in various applications, such as energy-saving substrates,
thermochromic windows, flame retardant materials, and more.
recyclability, biodegradability, and unique thermal and mechanical characteristics. Specifically, wood-based composites derived from natural wood exhibit significant potential for diverse applications, including building structures, packaging, and substrates for optoelectronic devices. Conventionally, transparent wood composites are developed in two steps. The wood is modified either through a delignification or bleaching process, followed by impregnating refractive index- matched polymers into the modified samples under vacuum. Paradoxically, current techniques for developing highly efficient transparent wood composites often involve the use of chemicals and petroleum-based polymers during fabrication, leading to adverse environmental effects. To address these challenges, this study aimed to develop a transparent wood bio-composite using non-toxic chemicals and bio-based resins. Non-toxic and volatile components, such as hydrogen peroxide (H2O2) and sodium hydroxide (NaOH), were utilized to modify the lignin content in balsa wood through a bleaching process. Subsequently, these bleached samples were impregnated with bio-based resin instead of petroleum-based resins. The study conducted a comparative analysis of the
performance of two types of bio-based epoxy resins (Polar Bear epoxy (PB-R) and Soya Resin (SG-30 R)) with synthetic epoxy resin (E-30-R). Generally, the transparency of the obtained composites is mainly influenced by the ratio of resin to hardener, curing conditions, and the duration of resin impregnation. The polymer infiltrates the porous structure of the balsa wood during infiltration, resulting in a transparent wood bio-composite. Optical, morphological, thermal, and mechanical studies were conducted using UV-Vis spectrophotometer, scanning electron microscope, differential scanning calorimeter, and a tensile testing machine, respectively. The soya resin- infiltrated transparent wood composite exhibited a combination of better optical transparency (83% at 550 nm), high haze (85%), ultraviolet-blocking efficiency, and hydrophobic nature compared to other composites. Furthermore, the use of bio-based materials (wood and bio-based resin) has a lesser environmental impact, making the developed composite a promising and environmentally friendly material for further exploitation in various applications, such as energy-saving substrates,
thermochromic windows, flame retardant materials, and more.