DOI
https://doi.org/10.25772/04E7-2523
Defense Date
2025
Document Type
Thesis
Degree Name
Doctor of Philosophy
Department
Chemistry
First Advisor
Everett Carpenter
Second Advisor
Massimo Bertino
Abstract
This dissertation investigates the synthesis, characterization, and scale-up of aerogels derived from both synthetic resorcinol–formaldehyde (RF) and natural polymer (pectin) systems. The work focuses on developing cost-effective, industrially scalable fabrication routes that maintain high surface area, low thermal conductivity, and structural integrity. Phenolic RF aerogels were synthesized using catalysts including sodium silicate, diethylenetriamine (DETA), and 3-aminopropyltrimethoxysilane (APTMS) under freeze-drying and ambient pressure drying (APD) conditions. APTMS-based systems achieved surface areas above 600 m²/g with 30 to 50 percent lower shrinkage than conventional formulations. Camphene was introduced as a novel APD solvent, producing aerogels with pore architectures comparable to freeze-dried materials and thermal conductivities as low as 23 mW/m·K (R ≈ 4.1 per inch).
Biopolymer-based pectin aerogels were synthesized using sodium silicate as both catalyst and silicate source, enabling drying via tert-butanol or camphene. These gels achieved surface areas up to 80 m²/g, densities of 0.12 g/cm³, and thermal conductivities near 27 mW/m·K. BET and BJH analyses confirmed mesoporosity (10 to 40 nm), while SAXS and SEM verified structural uniformity.
Both aerogel systems were successfully upscaled to 14 cm × 14 cm × 1 cm panels through mold-assisted gelation and controlled solvent exchange. Cost modeling indicates that large-scale pectin aerogel production with greater than 99.9 percent solvent recovery can be economically competitive with commercial thermal insulators. This research bridges laboratory-scale synthesis and industrial feasibility, providing mechanistic and process insights essential for scalable, sustainable aerogel manufacturing.
Rights
© The Author
Is Part Of
VCU University Archives
Is Part Of
VCU Theses and Dissertations
Date of Submission
10-9-2025