Lightweight and Thermally Insulating Nanowood

Annually, building consumes about 40% of total energy in the United States, greater than industrial and transportation. High-performance thermal insulation technologies for retrofitting existing building is urgently need to further improve its energy efficiency. The overall research objective for SBIR phase I is to demonstrate scalable thermal insulating nanowood with optimized thermal and mechanical properties suitable for energy efficiency building retrofit applications. We will have four tasks including: (1) develop and optimize delignification process to achieve nanowood with engineered nanopores; (2) investigate various properties of nanowood such as mechanical strength and toughness, thermal conductivity (resistance), UV and environmental stability, and fire resistance; (3) carry out cost analysis and investigate scale up manufacturing; and (4) evaluate the potential commercialization of the thermal insulating white wood. Note that the thermal properties of nanowood can be modulated by carefully tuning the pore size of the material, as discussed in our preliminary result (Anisotropic, lightweight, strong, and super thermally insulating nanowood with naturally aligned nanocellulose, Science Advanced, Accepted). We already demonstrated that nanowood with mesopores can deliver a low thermal conductivity of ~0.025 W/mK, which needs to be further improved for the R-12 target. We will also collaborate with Dr. J.Y. Zhu in Forest Product Lab in Task 1 for wood characterizations and R-50 for potential commercialization evaluations in Task 4. We will continue working with Cardolite Spatiality Chemicals on polymer treatments of delignified wood for enhancing the environmental stabilities. If the project is extended to Phase II, Phase III and beyond with success, the proposed nanowood insulation technology will be able to be adopted for a range of thermal insulation applications. For example, the low- cost, lightweight, strong and super insulating nanowood can be added to walls of existing buildings with a simple payback period for retrofit projects ideally less than 5 years but no more than 10 years.