Inorganic-organic Nanocomposites & Nanoscale SurfaceModificationEnergy Consumption & Reduced Capital Costs Ted Wegner USDA Forest Service Forest Products Laboratory June 15, 2007
Technical Challenges Understand & control surface chemical reactivity Characterization of structures at nanoscale Measurement of physical properties at nanoscale Multiple material compatibility Directed self assembly of nano-components Focus Area 4: Inorganic-organic nanocomposites nanoscale surface modification Target: Produce nano-composite materials from forest materials
enamel dentin bone nacre Strength of Materials: building blocks and interfaces Gecko Feet Source :K Autumn, PNAS 2006 Source :Gao, Fratzl et al, PNAS 2004
Perceived Issues with Wood-based Composites • Low strength and stiffness with eventual rheological/creep problems • Poor durability and water-related problems • Limited service life • Limited or poor fire performance • Requirement for enhanced performance, durability, fire resistance, and service life in non-residential construction
Nanotechnology Advanced Wood-based Composites • Natural composite components • Combined wood and natural biofiber composites possessing synergistic performance and service life using bio-based resins • Totally bio-based, sustainable composites • High-performance bio-based composites using inorganic binders or natural bio-based binders such as lignin • Biomimetic composites • Self-healing systems that include resins or sub-systems that reactivate when they sense degeneration of bond properties or mechanical displacement • Recycled materials • Systems that promote use of recycled materials • Systems that enhance its later recyclability
Nanotechnology Advanced Wood-based Composites • Smart composites • Systems that sense and warn users of mechanical overload • Systems that sense moisture and warn users of its presence • Systems that sense fungal or enzymatic activity and react to suppress it • Systems that sense fire and react to suppress and extinguish it • Additives (such as wax, preservative chemicals, fire retardants) • Systems that enhance bonding by acting as coupling agents • Systems that result in water-resistant—even water-proof—constituent materials • Binders • New bio- or synthetic-based binders with enhanced performance • Environmentally responsible and sustainable binder systems
Nanotechnology for Reduced Energy Consumption & Reduced Capital Costs
Objectives Apply nanotechnology and employ nanomaterials in forest products processing in order to reduce manufacturing costs by both reducing the amount of energy consumed during processing and capital equipment required.
Nanotechnology applications can take the forms of: • nano-catalysts to reduce the temperatures and time needed to delignify wood in pulping; • low corrosion nano-coatings and nano-materials to prolong the life of capital equipment; • nano-dimensional tags/markers for fiber separations; • nano-inspired products that help with water removal on paper machines (drainage wires, vacuum boxes, wet presses, and dryers), kilns, and hot presses; • robust nano-dimensional sensors (temperature, pressure, tensile/compressive forces, etc.) that can be used to monitor and optimize processing conditions as well as reduce/eliminate off specification product productions; etc.
Pulping and Paper/Paperboard Production Targets • Reduce pulping process energy consumption by at least 33% and produce the same or better quality fiber at 5-10% higher yield • Reduce energy consumed in the process of increasing black liquor solids (kraft pulping) by at least 50% • Develop lower-cost technology to replace the current (energy and capital intensive) causticizing process • Reduce energy and produce same or better-quality paper products by using: (a) nano-coating pigments and (b) three times the non-fiber filler content • Reduce the energy consumed in paper dewatering, pressing, and drying by at least 50%
Waste Streams/Wastewater • develop cost-effective methods to reduce or eliminate odorous kraft emissions beyond the mill property • Develop alternative methods for wastewater treatment that are less energy- and capital-intensive than current biological effluent treatment systems. • Develop low corrosion nano-coatings and nano-materials to prolong the life of capital equipment
Fiber Recovery and Recycling • Develop functional nanomaterials to enable paper and fiber tagging • Use nanomaterials to facilitate ink removal (i.e. de-inking) and contaminant removal • Develop low corrosion nano-coatings and nano-materials to prolong the life of capital equipment • Develop nanomaterials to improve recyclability of paper and paperboard products
Wood Products • Reduce VOC and HAP emissions from manufacturing wood-based products by 90% • Use nanoscale materials and technology to improve conversion efficiencies of wood products • Use nano-coatings and nano-catalysis to decrease emissions to indoor air from wood-based products by 50% • Investigate ways to use nanotechnology and nanomaterials to enhance and increase the efficiency of drying wood and wood-based materials in kilns and presses • Increase marketable chemical byproducts of wood by 10% • Employ robust nano-dimensional sensors (temperature, pressure, tensile/compressive forces, etc.) to monitor and optimize processing conditions and improve conversion yields as well as reduce/eliminate off specification product productions; etc.