Polymeric electrospun mats reinforced with nanofibrillated cellulose and cellulose nanocrystals: characterization of the micromechanical and compressive properties and evaluation of their influence in aerosol filtration

• Grant number: 19/20626-8
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• Effective date (Start): February 01, 2020
• Effective date (End): January 31, 2021
• Field of knowledge: Engineering - Civil Engineering - Construction Industry
• Principal Investigator: Holmer Savastano Junior
• Grantee: Rachel Passos de Oliveira Santos
• Supervisor: Gregory C. Rutledge
• Host Institution: Faculdade de Zootecnia e Engenharia de Alimentos (FZEA). Universidade de São Paulo (USP). Pirassununga , SP, Brazil
• Research place: Massachusetts Institute of Technology (MIT), United States
• Associated to the scholarship: 17/19549-3 - Preparation of new materials for application as filtration systems and evaluation of their efficiency in air conditioning devices for buildings: Mats of ultrathin fibers/nanofibers, porous sheets and multi-layer-structured polymeric materials reinforced, BP.PD

Abstract

Due to their outstanding characteristics, such as high porosity, as well as high specific surface area, electrospun mats have been increasingly used as air filter media. Although they can present such features, there may be some drawbacks, e.g., poor mechanical properties, high compressibility, and low filtration efficiency, that can limit their use as aerosol filters. The current post-doctoral project focus on the production of electrospun mats based on commodity polymers reinforced with nanofibrillated cellulose (NFC) to be used as air filters for indoors, aiming at the ideal combination between their porosity, permeability and mechanical strength. Complementarily to what has been developed, this project proposes a better understanding of the micromechanical properties of the electrospun mats, based on PAN and PMMA reinforced by NFC and cellulose nanocrystals (CNCs), via tensile tests considering a single fiber and also fibers web. The compressive properties of these materials will be also evaluated, as well as the influence of a thermal annealing process (aiming to improve the mechanical strength of the composite mats) on them. Solid and liquid aerosols will be generated and filtration tests will be performed. Therefore, in addition to the mechanical strength and compressibility of the materials, the filtration parameters, such as pressure drop, will be evaluated and optimized, focusing on the performance of the composite electrospun mats as HEPA filters for indoor air quality. (AU)