One-Component Composites based on Nanorods: From fundamental studies to multifunctional materials
Abstract
The proposed effort is focused on the design, synthesis, and characterization of a novel class of multi-functional, one-component nanocomposites based on polymer-grafted nanorods. As a one-component system, the proposed materials systems will be studied with the ultimate goal to create reinforced materials that do not suffer from the issues of mixing and phase separation observed in standard multi-component composites. If successful, this effort will render multifunctional composite materials that feature a unique combination of high strength, stiffness, and toughness while also possessing advanced functional properties such as healability, sensing capabilities, and mechanical adaptivity. To achieve the aforementioned objective of creating multifunctional one-component nanocomposites (OCNs), the PIs will employ a range of chemistries to graft selected polymers from the surface of cellulose nanocrystals (CNCs) which are highly crystalline rod-like nanoparticles that bear hydroxyl groups on their surface, making them amenable to functionalization with polymers. Radical polymerization and anionic ring-opening polymerization techniques will be employed to prepare OCNs functionalized with 1) homopolymers, 2) block copolymers, and 3) polymers with functional chain ends. It is expected that OCNs bearing homo- and block polymers will afford processible nanocomposites with simultaneously high strength, stiffness, and toughness and chain-end functionalized OCNs will provide access to multifunctional, stimuli-responsive composite materials. FT-IR spectroscopy will be employed to confirm attachment of polymer to CNC surface and thermogravimetric analysis will be used to determine the amount of polymer functionalized. AFM and/or TEM will be used to confirm no erosion to the CNC during the grafting process. Wide angle x-ray scattering will be used to confirm the crystallinity of the CNC. Polymers will be cleaved from the CNC surface and characterized via size exclusion chromatography and nuclear magnetic resonance. The ONCs will be processed by either casting from solution or melt-processing and their morphology will be investigated via a number of techniques including optical microscopy, TEM, SAXS, and AFM. Mechanical properties of the materials will be probed via DMTA and tensile testing; rheology will be employed to study mechanical properties under the application of external stimuli as this will allow for the studying the structure and properties of structurally dynamic OCNs.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jan 12, 2017
- Source ID
- W911NF1510190
Entities
People
- David Schiraldi
Organizations
- Army Contracting Command
- Case Western Reserve University
- United States Army