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Abstract High performance thermal insulation materials are desired for a wide range of applications in space, buildings, energy, and environments. Here, a facile ambient processing approach is reported to synthesize a highly insulating and flexible monolithic poly(vinyl chloride) aerogel. The thermal conductivity is measured respectively as 28 mW (m K)−1at atmosphere approaching the air conductivity and 7.7 mW (m K)−1under mild evacuation condition. Thermal modeling is performed to understand the thermal conductivity contributions from different heat transport pathways in air and solid. The analysis based on the Knudsen effect and scattering mean free paths shows that the thermal insulation performance can be further improved through the optimization of porous structures to confine the movement of air molecules. Additionally, the prepared aerogels show superhydrophobicity due to the highly porous structures, which enables new opportunities for surface engineering. Together, the study demonstrates an energy‐saving and scalable ambient‐processing pathway to achieve ultralight, flexible, and superhydrophobic poly(vinyl chloride) aerogel for thermal insulation applications.
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Microbial Synthesis of High-Molecular-Weight, Highly Repetitive Protein Polymers
High molecular weight (MW), highly repetitive protein polymers are attractive candidates to replace petroleum-derived materials as these protein-based materials (PBMs) are renewable, biodegradable, and have outstanding mechanical properties. However, their high MW and highly repetitive sequence features make them difficult to synthesize in fast-growing microbial cells in sufficient amounts for real applications. To overcome this challenge, various methods were developed to synthesize repetitive PBMs. Here, we review recent strategies in the construction of repetitive genes, expression of repetitive proteins from circular mRNAs, and synthesis of repetitive proteins by ligation and protein polymerization. We discuss the advantages and limitations of each method and highlight future directions that will lead to scalable production of highly repetitive PBMs for a wide range of applications.
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- PAR ID:
- 10414748
- Date Published:
- Journal Name:
- International Journal of Molecular Sciences
- Volume:
- 24
- Issue:
- 7
- ISSN:
- 1422-0067
- Page Range / eLocation ID:
- 6416
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/ijms24076416
