RUI:Dielectric Permittivity and Charge Transport in Electroactive Polymer Nanofibers: Motivating Undergraduates to Pursue Graduate Studies in Materials Science

University Of Puerto Rico At Humacao, Humacao PR

Investigators

Abstract

TECHNICAL SUMMARY In this project electrospinning will be used to prepare nanofibers of electroactive polymers and their composite blends. The PI's approach to making polymer nanofibers via electrospinning differs from common approaches that typically use templates or other complex methods. The electro-active polymers include those that exhibit conducting, semiconducting and ferroelectric properties at room temperature. The fundamental charge transport mechanisms and charge storage in these polymer nanofibers will be investigated via temperature-dependent conductivity and dielectric permittivity measurements. Nanofibers naturally possess a confined environment for charge flow, thus the presence of defects will lead to changes in charge transport and provide a handle on how best to prepare defect-free nanofibers. A better understanding of charge transport and charge storage in conducting, semiconducting and ferroelectric polymers as proposed here might then be exported to other macromolecules that exhibit similar physical properties. The composite nanofibers retain the properties of the individual components and are thus inherently capable of being used in devices that are multifunctional and hence more versatile. Modified experiments based on the proposed research will be included into the senior laboratory course for undergraduates, thereby integrating research and education. NON-TECHNICAL SUMMARY The principal investigator (PI) proposes to prepare fibers of electrically active polymers having a diameter roughly one-one thousandth that of a human hair using an inexpensive fiber-spinning technique called electrospinning. The materials to be studied are special polymers that are individually capable of carrying a current or storing charge while at the same time are light in weight, flexible, and inexpensive to manufacture. By combining these polymers as composites, the current carrying capacity of one together with the charge storage capacity of the other will lead to novel materials that are more versatile. Fabricating nanofibers of such composite materials is new and unexplored, and the PI's ultimate goal is to make devices and sensors with superior properties. Devices fabricated from nanofibers are also expected to be small in size and to consume less power. The proposed research is multidisciplinary across polymer science, physics, nanoscience, and electronics, thus giving students a sound and direct research experience that will train them in the scientific method and prepare them to be future scientists and engineers. This proposal will also increase the number of undergraduate students participating in scientific research from groups currently underrepresented in the fields of science and engineering and will extend the PI's outreach to include an international collaboration.