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Short-Chain Modified SiO₂ with High Absorption of Organic PCM for Thermal Protection.

ABSTRACT: Organic phase change materials (PCMs) have great potential in thermal protection applications but they suffer from high volumetric change and easy leakage, which require "leak-proof" packaging materials with low thermal conductivity. Herein, we successfully modify SiO₂ through a simple 2-step method consisting of n-hexane activation followed by short-chain alkane silanization. The modified SiO₂ (M-SiO₂) exhibits superior hydrophobic property while maintaining the intrinsic high porosity of SiO₂. The surface modification significantly improves the absorption rate of RT60 in SiO₂ by 38%. The M-SiO₂/RT60 composite shows high latent heat of 180 J·g^-1, low thermal conductivity of 0.178 W·m^-1·K^-1, and great heat capacity behavior in a high-power thermal circuit with low penetrated heating flow. Our results provide a simple approach for preparing hydrophobic SiO₂ with high absorption of organic PCM for thermal protection applications.

SUBMITTER: Wang F

PROVIDER: S-EPMC6523198 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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Short-Chain Modified SiO2 with High Absorption of Organic PCM for Thermal Protection.

Wang Fuxian F Gao Shiyuan S Pan Jiachuan J Li Xiaomei X Liu Jian J

Nanomaterials (Basel, Switzerland) 20190425 4

Organic phase change materials (PCMs) have great potential in thermal protection applications but they suffer from high volumetric change and easy leakage, which require "leak-proof" packaging materials with low thermal conductivity. Herein, we successfully modify SiO2 through a simple 2-step method consisting of n-hexane activation followed by short-chain alkane silanization. The modified SiO2 (M-SiO2) exhibits superior hydrophobic property while maintaining the ...[more]

PMID: 31027214

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