Effect of EPS Particle Size Matching on the Performance of SiO₂ Aerogel Thermal Insulation Mortar Based on Microbial Foaming

Abstract

To solve the problems of high thermal conductivity and poor insulation performance of traditional inorganic insulation mortar, this paper develops a new type of inorganic insulation mortar with low thermal conductivity by using lightweight aggregates and combining foaming technology. The influence of polystyrene foam particle (EPS) gradation (0.5–0.8 mm, 1–2 mm and 2–3 mm) on the compressive strength, bonding strength, volume water absorption, drying shrinkage, softening coefficient, thermal conductivity, hydration and microstructure (XRD, NMR, CT) of SiO₂ aerogel insulation mortar based on microbial foaming was studied by using ternary phase diagram method. The results show that: (1) The decrease in the amount of small particle EPS resulted in an increase of 3.8% to 52.7% in the thermal conductivity of the insulation mortar specimens. When the content of small particle size EPS is fixed, the thermal conductivity of the insulation mortar specimens decreases by 17.8% to 26.4% as the content of medium particle size EPS increases and the content of large particle size EPS decreases synchronously; (2) The reduction of small particle size EPS content and the increase of medium and large particle size EPS content have an improving effect on the compressive strength and bond strength of insulation mortar, increasing by 12.0%–64.5% and 11.3%–59.1%, respectively; (3) The reduction of small particle size EPS content and the increase of medium and large particle size EPS content increased the volumetric water absorption rate (60.5%–130.0%), drying shrinkage rate (20.0%–160.0%), and softening coefficient (2.7%–8.0%) of the insulation mortar; (4) Changing the aggregate grading did not result in the formation of new hydrate phases in the insulation mortar, but only altered the slurry content of the insulation mortar specimens. Microscopic analysis shows that under various aggregate gradations, the pores of insulation mortar are mainly concentrated in capillary pores, and the EPS ratio of each particle size is 6:2:2, forming the most tightly packed group, which is the optimal aggregate gradation; (5) From the perspective of insulation performance, the optimal grading of EPS is 6:2:2. At this time, the thermal conductivity of the insulation mortar is 0.031 3 W/(m·K), the compressive strength is 102.5 kPa, the bonding strength is 156.8 kPa, the volumetric water absorption rate is 4.3%, the drying shrinkage rate is 0.5%, and the softening coefficient is 0.75.

Keywords

EPS particle size distribution / SiO₂ aerogel / thermal insulation mortar / microbial foaming agent

References

[1] Fan Z LResearch on System Optimization of Mixed Utilization of New Energy and Traditional Energy[J]. Urban Construction Theory Research, 2024, 08: 97-99

[2] Liu J HVigorously Promote Energy and Resource Conservation, Intensive and Efficient Utilization Throughout the Entire Process[J]. China Petroleum and Chemical Industry, 2024, 06: 30-32

[3] Liu JResearch on Energy Conservation Strategies in the Construction Technology of High Rise Green Building Materials[J]. Foshan Ceramics, 2024, 34(8): 73-75

[4] Liao LResearch on the Application of Efficient Thermal Insulation Materials in Green Buildings[J]. Neotype Urban Construction Technology, 2024, 33(10): 21-23

[5] Zhao Z MPreparation and Properties of Superhydrophobic SiO₂ Aerogel Composites, 2023, Mianyang: Southwest University of Science and Technology

[6] Zhang Y HStudy on Preparation and Thermal and Humidity Properties of SiO₂ Aerogel Thermal Insulation Composites, 2017, Guangzhou: Guangzhou University

[7] Wu D, Shao K, Sun T TPreparation and Performance Analysis of Silica Aerogel Modified Expanded Perlite Thermal Insulation Material [J]. Science and Technology Vision, 2017, 4: 49.

[8] Zeng Q, Mao T, Li H, et al.Thermally Insulating Lightweight Cement-based Composites Incorporating Glass Beads and Nano-silica Aerogels for Sustainably Energy-saving Buildings[J]. Energy and Buildings, 2018, 17497-110.

[9] de Fátima Júlio M, Soares A, Ilharco L M, et al.Aerogel-based Renders with Lightweight Aggregates: Correlation between Molecular/Pore Structure and Performance[J]. Construction and Building Materials, 2016, 124: 485-495.

[10] Wan Y, Wang J, Li ZEffect of Modified SiO₂ Aerogel on the Properties of Inorganic Cementing Materials[J]. Materials Letters, 2023, 341: 134 217.

[11] Adhikary S K, RudžionisTučkutė SCharacterization of Novel Lightweight Self-compacting Cement Composites with Incorporated Expanded Glass, Aerogel, Zeolite and Fly Ash[J]. Case Studies in Construction Materials, 2022, 16e00 879.

[12] Zhang X, Liu D, Wang D M, et al.Study on Preparation of Silica Aerogel-Glass Fiber Needled Felt Composites[J]. Tianjin Construction Science and Technology, 2019, 29(4): 58-60

[13] Xu Y FOverview and Application Research of Expanded Perlite Insulation Board[J]. Anhui Architecture, 2020, 27(8): 153-154

[14] Wang L, Peng H, Chen Y H, et al.Influence of Expanded Perlite Content on Properties of EPS Foam Concrete[J]. Journal of Hunan City University(Natural Science), 2023, 32(1): 17-23

[15] Zhou Y CPreparation and Performance Study of EPS/Gypsum Lightweight Thermal Insulation Wall Materials, 2020, Zhengzhou: Henan University

[16] Jin Q, Feng Y, He J C, et al.Research on the Thermal Insulation and Fireproof Performance of Gypsum-EPS-Cotton Straw Fiber Composite Material[J]. China Concrete and Cement Products, 2014, 251-53

[17] Jia KOptimization and Performance Study of Inorganic/Organic Composite External Wall Insulation EPS Material Ratio[J]. Adhesion, 2024, 51(09): 72-75

[18] Hou FFinite Element Analysis and Mechanical Experimental Study on the Thermal Insulation Performance of EPS Particle Filled Cementitious Composite Materials[J]. Jiangxi Building Materials, 2018, 09: 21-22

[19] Gao J F, Geng F, Yi G, et al.Research on EPS Composite Insulation Material for Flooring[J]. Low Temperature Architecture Technology, 2024, 46(3): 43-47

[20] Chen Y, Zhang W H, Zhang L, et al.Dynamic Impact Compressive Performance of Expanded Polystyrene (EPS)-foamed Concrete[J]. Archives of Civil and Mechanical Engineering, 2022, 22(4): 1-17

[21] Pedroso M, Flores-Colen I, Silvestre J D, et al.Physical, Mechanical, and Microstructural Characterisation of an Innovative Thermal Insulating Render Incorporating Silica Aerogel[J]. Energy and Buildings, 2020, 211: 109 793.

[22] Feng J C, Wang Y R, Geng J, et al.Experimental Study on the Influence of Aggregate Gradation and Content on the Performance of Silica Aerogel-vitrified Bead Composite Thermal Insulation Mortar[J]. Concrete, 2018, 04110-114

[23] Ji C B, Hu X M, Yin H YStudy on the Influence of Recycled EPS Grading on the Performance of EPS Insulation Mortar[J]. China Concrete and Cement Products, 2014, 4: 15-17

[24] Xie S J, Yang S Y, Zhang C G, et al.Experimental Study on Technical Performance of Recycled Brick Aggregate Foam Mortar[J]. New Building Materials, 2022, 49(10): 144-148

[25] Ding CPreparation and Performance Enhancement Mechanism of High Performance Expanded Perlite Thermal Insulation Mortar, 2022, Fuzhou: Donghua University of Technology

[26] Hu B C, Fu C Y, Li S SStudy on Preparation and Performance of High Performance Foam Concrete[J]. Journal of Functional Materials, 2024, 55(02): 2 181-2 1862 200

[27] Zeng Q L, Lin M Q, Yu Y, et al.Experimental Study on Properties of Recycled Powder Foam Concrete[J]. Henan Science, 2024, 42(12): 1 784-1 791

[28] Li XPreparation and Basic Properties of Recycled Micro Powder Foam Concrete, 2023, Beijing: Beijing Jianzhu University

[29] Zhang JPreparation of Biological Foaming Agent and Its Application in Foam Concrete, 2020, Tianjin: Tianjin Chengjian University

[30] Zhang NPreparation and Performance Study of Microbial Foamed Soil Materials, 2020, Tianjin: Tianjin Chengjian University

Rights & permissions

Wuhan University of Technology and Springer-Verlag GmbH Germany, Part of Springer Nature