Doctoral Dissertations
Catalytic Control of the Nanomorphology and Mechanical Properties of Aliphatic Shape-Memory Aerogels
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
Recommended Citation
Doulah, A B M Shaheen ud, "Catalytic Control of the Nanomorphology and Mechanical Properties of Aliphatic Shape-Memory Aerogels" (2024). Doctoral Dissertations. 3316.
https://scholarsmine.mst.edu/doctoral_dissertations/3316
