Structure Dynamics and Rheology of Preceramic Polymer Hairy Nanoparticles
Abstract
Nanoparticles. PI: S. Ramakrishnan, Florida Agricultural and Mechanical University (FAMU) Manufacturing bulk ceramic components from preceramic organosilicon polymers (polycarbosilanes) is of interest in a number of applications due to the tunability of their composition to get tailored microstructures. Grafting of these preceramic polymers (PCP) to nanoparticles (GNP) and subsequent composite formation overcome several difficulties during processing such as compatibility, agglomeration and phase separation. However, a fundamental study to determine structure-property relationships in such composite materials is still lacking. The aim of the current proposal is to perform a systematic study of the structure-property relationships in PCP-GNPs with a final goal of developing useful products for the Department of Defense (turbine engines, high-speed flight components). The development of PCP-GNPs is expected to significantly improve the production of high-temperature materials used in these applications. Interactions between nanoparticles will be tuned in several different ways (graft density and molecular weight of attached polymer, addition of mixtures of particles) and characterized by novel experimental methods (X-ray scattering at national labs, atomic force microscopy Ð DOD equipment grant awarded in 2022, nanoindentation). The assembly of the nanoparticles for a given interaction and the resultant dynamics (of particles and polymers) and macroscopic properties (rheology, toughness) will be studied experimentally, and material databases preserved for additional analysis. The production of hierarchically organized, low-density material structures will be enabled through additive manufacturing methods (3D printing coupled with laser annealing) which take advantage of the newly synthesized hybrid nanomaterials. There are three main aims Ð 1) Synthesis and structure-property relationships in model PCP GNPs. 2) 3D printing hairy nanoparticle assemblies and 3) Mechanical properties and toughness of PCP GNPs coupled with data fusion analysis. DOD Merit: 1) The work will result in hierarchically structured low density ceramic materials of interest to the DOD. The systematic study proposed here will result in novel design rules for the processing of the PCP GNPs. 2) Direct ink writing coupled with laser annealing will result in fabricated ceramic structures with enhanced properties (toughness, thermal management). 3) The detailed experimental characterization of the microstructure, dynamics and mechanical response in these materials will provide a series of benchmarks for rigorous testing of different theories. Of particular importance will be the local structure and toughness characterization with the newly awarded DOD instrumentation. 4) Novel experimental techniques to study soft condensed matter will be developed at Brookhaven National Labs to characterize the interactions between nanoparticles and the resultant structure and dynamics of nanoparticle systems. This will be extremely useful to a number of other users at defense labs. Impact on FAMU: 1) The project will play a key role in the education of minority students in material science and expose them to state-of-the-art research facilities. It will play an important role in FAMU s Materials Science and Engineering Program, assisting the university in achieving R1 status. 2) Collaborations with AFRL and ARL will strengthen the research program at FAMU and enhance sustainability. 3) Internship program in collaboration with DOD agencies will enhance the education of minority students Ð in line with the mission of DOD. 4) Coupled with the recently awarded NSF grant, Minority Leaders Grant from AFRL and existing NSF CREST CENTER grant (which will support graduate students & internships) the proposal will emphasize core research infrastructure at FAMU to become a world leader of additive manufacturing technology.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- May 24, 2023
- Source ID
- W911NF2310172
Entities
People
- Subramanian Ramakrishnan
Organizations
- Army Contracting Command
- Florida A&M University
- Office of the Secretary of Defense