Doctoral Dissertations

Keywords and Phrases

Aerogels; Benzoxazine; Energy Storage; Shape Memory; Superelastic; Thermites

Abstract

"Aerogels are three dimensional highly porous solid objects that provide density reduction compared to dense objects. Those materials can have applications in different classes of energy storage and the two types that are focused in this dissertation are mechanical energy and thermal energy storage. Shape memory materials can store and recover elastic deformation energy when triggered by an external stimulus such as temperature. To incorporate those properties, shape memory polymeric aerogels (SMPA) were synthesized from a rigid isocyanurate containing triisocyanate (N3300 A) and four short oligomeric derivatives of ethylene glycol: H(OCH2CH2)nOH (1 ≤ n ≤ 4). The shape memory effect (SME) of those aerogels were evaluated via four figures of merit namely strain fixity, strain recovery, strain recovery rate and fill factor. The morphologies of skeletal frameworks of those aerogels varied from micrometer sized particles with thick necks to bicontinuous structures, that are typical of spinodal decomposition. A Marcus-type thermodynamic-kinetic relationship was identified between that shape recovery rate, Rt(N), and the elastic modulus, E. Other part of the dissertation deals with the synthesis of nanoporous metallic iron (Fe(0)) aerogels via carbothermal reduction of interpenetrating networks of polybenzoxazine and iron oxide nanoparticles. Excess carbon was removed oxidatively at 600 ⁰C under flowing air and the oxides of Fe(0) thus produced in the oxidative step were reduced back to Fe(0) with H2 at different temperatures ranging from 300 - 1300 ⁰C. Those final monoliths were loaded with perchlorates and ignited with a flame in open air. Based on the temperature of the reduction step, monoliths either fizzled out ( ≤ 400 ⁰C), exploded violently (500-900 ⁰C), or behaved as thermites ( ≥ 950 ⁰C)"--Abstract, page v

Advisor(s)

Leventis, Nicholas
Sotiriou-Leventis, Lia

Committee Member(s)

Choudhury, Amitava
Nath, Manashi
Liang, Xinhua

Department(s)

Chemistry

Degree Name

Ph. D. in Chemistry

Sponsor(s)

United States Army Research Office

Comments

Army Research Office financial support under Award Number W911NF-14-1-0369 and under Cooperative Agreement No. W911NF-12-2-0029

Publisher

Missouri University of Science and Technology

Publication Date

Spring 2018

Journal article titles appearing in thesis/dissertation

  • Shape-memory superelastic poly(isocyanurate-urethane) aerogels (PIR-PUR) for deployable panels and biomimetic applications
  • Nanostructure-dependent thermodynamic-kinetic correlation of the shape recovery rate and the Young's Modulus in shape-memory polymer aerogels
  • Explosive versus thermite behavior in iron(0) aerogels infiltrated with perchlorates

Pagination

xix, 247 pages

Note about bibliography

Includes bibliographic references.

Rights

© 2018 Suraj Donthula, All rights reserved.

Document Type

Dissertation - Open Access

File Type

text

Language

English

Thesis Number

T 11274

Electronic OCLC #

1041857895

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Included in

Chemistry Commons

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