Doctoral Dissertations

Abstract

"Shape-memory poly(isocyanurate-urethane) (PIR-PUR) aerogels are nanoporous solids that can return to their original shape after being compressed, through a heating actuation step. This thesis compares the effectiveness of various metal ions as catalysts in the formation of PIR-PUR aerogels, and explores the correlation between catalytic activity, nanomorphology, and mechanical properties of the resulting aerogels. The gelation rate was found to increase from Fe to Cu and then decline from Cu to Ga in the periodic table. CuCl2 was found to be the fastest catalyst, and FeCl3 the slowest. The morphology of the aerogels changed from bicontinuous to spheroidal as the catalyst concentration decreased. The elastic modulus (E) was found to be correlated with gelation time, by tuning the nano porosity of PIR-PUR aerogels.

The shape-memory of PIR-PUR aerogels was also used for synthesizing meta-materials by tuning the micro porous design of flexible aerogels. The shape-memory response of these aerogels has been improved by incorporating an auxetic effect, resulting in a negative Poisson's ratio. This means that the aerogels experience volume contraction upon compression and can be stored indefinitely in a temporary shape by cooling below the glass transition temperature. Upon heating above the glass transition temperature, the compressed form expands to its original shape/size. This technology has various applications in commercial, aeronautical, and aerospace industries, including minimally invasive medical devices, soft robotics, and storage of deployable space structures and planetary habitats during transport" -- Abstract, p. iv

Advisor(s)

Sotiriou-Leventis, Lia

Committee Member(s)

Nath, Manashi
Winiarz, Jeffrey G.
Reddy, Prakash, -2024
Miller, F. Scott, 1956-

Department(s)

Chemistry

Degree Name

Ph. D. in Chemistry

Publisher

Missouri University of Science and Technology

Publication Date

Summer 2024

Pagination

xvi, 140 pages

Note about bibliography

Includes_bibliographical_references_(pages 52, 94 & 135-139)

Rights

©2024 A B M Shaheen ud Doulah , All Rights Reserved

Document Type

Dissertation - Open Access

File Type

text

Language

English

Thesis Number

T 12423

Electronic OCLC #

1460024968

Included in

Chemistry Commons

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