Subcategory: Chemistry (not Biochemistry)
Shirnece Brown - Clark Atlanta University
Co-Author(s): Ishrat Khan and Xiao-Qian Wang, Clark Atlanta University, Atlanta, GA
Integrating computational and experimental approaches and how the approaches not only permit better interpretation of experimental results but also to assess the effectiveness of our computational methods to design new materials. One of the most fundamental approaches to improve properties of polymers is by designing composites (or nanocomposites) by addition of nanoparticles within the polymer matrix. One particle that can significantly improve properties of a polymer is single-walled carbon nanotubes (SWNTs). These are attractive materials due to their intrinsic electronic, mechanical, and transport properties. However, SWNTs typically exist in the aggregated form in polymer matrices, in which tubes of different properties are held together to prevent the optimum performances of SWNTs, due to the strong π-π interaction among the tubes. Therefore, one of the most fundamental studies that is essential to carry out before preparing SWNT composite with any polymers is the nature of the interaction of the SWNT with the polymer. In order to improve design efficiency of new composites, we integrate computational and experimental approaches. In this particular study, the nature and the strength of the interaction between SWNT and poly(ether imide) (PEI) is determined. Polyetherimide (PEI) is a high performance engineering thermoplastic. PEI’s characteristics include high strength and rigidity at elevated temperatures, long term heat resistance, dimensional stability and good electrical properties. Poly (ether imide) (PEI) is an attractive material due to its favorable physical and electronic properties. In order to shed some light on the dispersion selectivity, the computational study was carried out by using dispersion-corrected, DFTB+ method. Interaction of the crosslinked, i.e. the ability and capacity of PEI to interact with SWNT and the effect of the interaction when the PEI is crosslinked has also been studied. The calculations suggest that PEI (crosslinked and uncrosslinked) is effective in interacting with SWNT. We are currently determining if the computational results can be validated by the experimental results. The experiments are currently being carried out. The long range goal is to develop computational approaches which will permit computationally aided design of advanced nanocomposites.
Funder Acknowledgement(s): NSF CREST HRD-1137751
Faculty Advisor: Ishrat Khan, Ikhan@cau.edu
Role: The extent of my involvement in the research of poly(ether imide) (PEI)/singled-walled carbon nanotubes (SWNTs) includes performing computational and experimental analysis on the composite. Computational work conducted was carried-out using Materials Studio software. Calculations were achieved using Forcite Geometry Optimization and Dynamics. Future work includes the incorporation of amorphous cell and DFTB+ methods. The experimental approach, thus far, includes the use of solution and solid state NMR. Future efforts incorporate T1ρ , DSC, AFM, and SEM.