Gels as High-Performance Thermal Insulation Materials

A special issue of Gels (ISSN 2310-2861). This special issue belongs to the section "Gel Chemistry and Physics".

Deadline for manuscript submissions: closed (30 September 2023) | Viewed by 11106

Special Issue Editors

School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
Interests: nanofiber; wearable electronics; flexible electrode; gels

E-Mail Website
Guest Editor
State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, China
Interests: nanofiber materials; gels
Institute of Advanced Structure Technology, Beijing Institute of Technology, Beijing 100081, China
Interests: aerogel; porous material; thermal insulation material; coating material; gels
Special Issues, Collections and Topics in MDPI journals

E-Mail Website
Guest Editor
Polymer Aerogels Research Center, International Institute for Innovation, Jiangxi University of Science and Technology, Nanchang 330013, China
Interests: polymer aerogels; thermal insulation; polyimide; thermal protection materials in aerospace; gels

Special Issue Information

Dear Colleagues,

To fight against climate change and the energy crisis, the burgeoning trend of high-performance thermal insulation materials is set for continued disruption of the multifaceted, mass-market fire protection, transportation, petroleum, chemical, and architecture industry. Traditional thermal insulation materials (fiberglass, expanded polystyrene, polyurethane, mineral wool, etc.) become challenging to meet the requirement for high-tech equipment. Therefore, developing new-type thermal insulation materials become a significant trend in developing thermal insulation materials. Among them, the gel is one of the most promising high-performance thermal insulation materials. The slow and arduous process of overhauling of such an industry is underway, with the gels taking a stronghold as the dominant thermal insulators. With that, the gel design remains dynamic as it trends toward a shared understanding of best practices.

For the gel insulation material, there are still some key issues that need to be investigated to get a deep understanding of the mechanism of nanoscale heat transfer inside the material, such as the coupled heat transfer behavior at the gas-solid contact interface, the influence of scale effect/interfacial effect on the thermal conductivity of nanoscale solid particles, etc. Moreover, the low-cost, large-scale, and continuous preparation technology for high-performance gel thermal insulation materials must be developed. Thus, it is necessary to keep on investigating these questions thoroughly to provide help for optimizing the insulation performance of the material.

This Special Issue is a comprehensive collection of articles dealing with the synthesis and characterization of emerging aerogel- or hydrogel-based thermal management materials. The author shows the heat transfer mechanisms, mechanical characteristics, or possible applications. Publication of original research articles, rapid communications, or reviews in this Special Issue will make an important contribution to developing gel thermal insulation materials.

Dr. Lei Li
Prof. Dr. Yang Si
Dr. Baosheng Xu
Dr. Sizhao Zhang
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Gels is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • aerogel
  • gels materials
  • gels composite
  • hydrogels
  • thermal insulation

Published Papers (4 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

Jump to: Review

13 pages, 7214 KiB  
Article
Preparation and Properties of Highly Transparent SiO2 Aerogels for Thermal Insulation
by Baolu Shi, Long Xie, Bin Ma, Zhiliang Zhou, Baosheng Xu and Lijie Qu
Gels 2022, 8(11), 744; https://doi.org/10.3390/gels8110744 - 16 Nov 2022
Cited by 7 | Viewed by 3171
Abstract
SiO2 aerogels have attracted extensive attention due to their unique structural characteristics, which exhibit many special properties, especially good optical transparency. As far as we know, the sol-gel stage during the synthesis of aerogel plays an important role in the construction of [...] Read more.
SiO2 aerogels have attracted extensive attention due to their unique structural characteristics, which exhibit many special properties, especially good optical transparency. As far as we know, the sol-gel stage during the synthesis of aerogel plays an important role in the construction of the gel skeleton. In this study, we adjusted the amount of silicon source and catalyst to explore the best scheme for preparing highly transparent SiO2 aerogels, and further clarify the effects of both on the properties of SiO2 aerogels. Results indicated that the pore size distribution was between 10 and 20 nm, the thermal conductivity was between 0.0135 and 0.021 W/(m·K), and the transmittance reached 97.78% at 800 nm of the aerogels, better than most studies. Therefore, it has the potential to be used in aerogel glass for thermal insulation. Full article
(This article belongs to the Special Issue Gels as High-Performance Thermal Insulation Materials)
Show Figures

Figure 1

13 pages, 4333 KiB  
Article
Hydrophobic Cellulose Acetate Aerogels for Thermal Insulation
by Sizhao Zhang, Zhouyuan Yang, Xing Huang, Jing Wang, Yunyun Xiao, Junpeng He, Jian Feng, Shixian Xiong and Zhengquan Li
Gels 2022, 8(10), 671; https://doi.org/10.3390/gels8100671 - 19 Oct 2022
Cited by 7 | Viewed by 2550
Abstract
As naturally derived material, cellulose aerogels have excellent thermal insulation properties due to their unique high porosity and three-dimensional mesoporous structure. However, its hydrophilic properties limit its application in the field of building insulation. Here, we propose a method to prepare high hydrophobicity [...] Read more.
As naturally derived material, cellulose aerogels have excellent thermal insulation properties due to their unique high porosity and three-dimensional mesoporous structure. However, its hydrophilic properties limit its application in the field of building insulation. Here, we propose a method to prepare high hydrophobicity by adopting the sol-gel method and chemical vapor reaction strategy using cellulose acetate type II as raw material and 2,4-toluene diisocyanate as the cross-linking agent. Thermal properties of cellulose acetate aerogels (CAAs) were measured, where pyridine was the catalyst, acetone was the solvent, and perfluorodecyltriethoxysilane (PFDS), hexamethyldisilazane (HMDS), and methyltriethoxysilane (MTES) were used as hydrophobic agents (by process hydrophobic test). Compared with MTES-modified cellulose acetate aerogels (M-CAAs) and HMDS (H-CAAs)-modified cellulose acetate aerogels, PFDS-modified (P-CAAs) cellulose acetate aerogels are the most hydrophobic. By implementing hydrophobic modification of PFDS both inside and outside the structure of cellulose acetate aerogels, the water contact angle can reach up to 136°, strongly demonstrating the potential of PFDS as a hydrophobic agent. The results show that the thermal conductivity and compressive strength of cellulose acetate aerogel with the best hydrophobic properties are 0.035 W m−1 K−1 at normal pressure and 0.39 MPa at 3% strain, respectively. This work shows that the highly hydrophobic cellulose acetate aerogel has potential as a waterproof material in the field of building thermal-insulation materials. Full article
(This article belongs to the Special Issue Gels as High-Performance Thermal Insulation Materials)
Show Figures

Graphical abstract

Review

Jump to: Research

25 pages, 5271 KiB  
Review
Alumina Ceramic Nanofibers: An Overview of the Spinning Gel Preparation, Manufacturing Process, and Application
by Meng Xia, Shuyu Ji, Yijun Fu, Jiamu Dai, Junxiong Zhang, Xiaomin Ma and Rong Liu
Gels 2023, 9(8), 599; https://doi.org/10.3390/gels9080599 - 25 Jul 2023
Cited by 3 | Viewed by 1688
Abstract
As an important inorganic material, alumina ceramic nanofibers have attracted more and more attention because of their excellent thermal stability, high melting point, low thermal conductivity, and good chemical stability. In this paper, the preparation conditions for alumina spinning gel, such as the [...] Read more.
As an important inorganic material, alumina ceramic nanofibers have attracted more and more attention because of their excellent thermal stability, high melting point, low thermal conductivity, and good chemical stability. In this paper, the preparation conditions for alumina spinning gel, such as the experimental raw materials, spin finish aid, aging time, and so on, are briefly introduced. Then, various methods for preparing the alumina ceramic nanofibers are described, such as electrospinning, solution blow spinning, centrifugal spinning, and some other preparation processes. In addition, the application of alumina ceramic nanofibers in thermal insulation, high-temperature filtration, catalysis, energy storage, water restoration, sound absorption, bioengineering, and other fields are described. The wide application prospect of alumina ceramic nanofibers highlights its potential as an advanced functional material with various applications. This paper aims to provide readers with valuable insights into the design of alumina ceramic nanofibers and to explore their potential applications, contributing to the advancement of various technologies in the fields of energy, environment, and materials science. Full article
(This article belongs to the Special Issue Gels as High-Performance Thermal Insulation Materials)
Show Figures

Graphical abstract

36 pages, 10580 KiB  
Review
Fabrication and Applications of Ceramic-Based Nanofiber Materials Service in High-Temperature Harsh Conditions—A Review
by Jing Zhang, Xi Zhang, Lifeng Wang, Junxiong Zhang, Rong Liu, Qilong Sun, Xinli Ye and Xiaomin Ma
Gels 2023, 9(3), 208; https://doi.org/10.3390/gels9030208 - 09 Mar 2023
Cited by 6 | Viewed by 2409
Abstract
Ceramic-based nanofiber materials have attracted attention due to their high-temperature resistance, oxidation resistance, chemical stability, and excellent mechanical performance, such as flexibility, tensile, and compression, which endow them with promising application prospects for filtration, water treatment, sound insulation, thermal insulation, etc. According to [...] Read more.
Ceramic-based nanofiber materials have attracted attention due to their high-temperature resistance, oxidation resistance, chemical stability, and excellent mechanical performance, such as flexibility, tensile, and compression, which endow them with promising application prospects for filtration, water treatment, sound insulation, thermal insulation, etc. According to the above advantages, we, therefore, reviewed the ceramic-based nanofiber materials from the perspectives of components, microstructure, and applications to provide a systematical introduction to ceramic-based nanofiber materials as so-called blankets or aerogels, as well as their applications for thermal insulation, catalysis, and water treatment. We hope that this review will provide some necessary suggestions for further research on ceramic-based nanomaterials. Full article
(This article belongs to the Special Issue Gels as High-Performance Thermal Insulation Materials)
Show Figures

Figure 1

Back to TopTop