Preparation and characterization of diphenyl silicone rubber/microfiber glass wool composite thermal control films

• Published in: RSC advances 2023-05, Vol.13 (23), p.1541-1549
• Main Authors: Li, Lin, Fu, Xin, Xu, Xiang, Wei, Dafu, Guan, Yong
• Format: Article
• Language: English
• Subjects: Chemistry; Condensates; Copolymers; Diameters; Diffusion coefficient; Dimensional stability; Glass transition temperature; Glass wool; Infrared radiation; Low temperature; Low temperature resistance; Microfibers; Microscopy; Optical microscopy; Room temperature; Silica glass; Silicone rubber; Silicones; Spacecraft; Stability analysis; Temperature control; Thermal conductivity; Thermal control coatings; Thermal decomposition; Thermal diffusion; Thermal expansion; Thermal insulation; Thin films
• ISSN: 2046-2069; 2046-2069
• DOI: 10.1039/d3ra02118a

Innovative research on the development of thermal control films for spacecraft surfaces is presented. A hydroxy-terminated random copolymer of dimethylsiloxane-diphenylsiloxane (PPDMS) was prepared from hydroxy silicone oil and diphenylsilylene glycol by a condensation reaction, and then liquid diphenyl silicone rubber base material (denoted as PSR) was obtained by adding hydrophobic silica. Microfiber glass wool (MGW) with a fiber diameter of ∼3 μm was added to the liquid PSR base material, which upon solidifying at room temperature, formed a 100 μm thick PSR/MGW composite film. The infrared radiation properties, solar absorption, thermal conductivity, and thermal dimensional stability of the film were evaluated. Moreover, the dispersion of the MGW in the rubber matrix was confirmed by optical microscopy and field-emission scanning electron microscopy. The PSR/MGW films exhibited a glass transition temperature of −106 °C, thermal decomposition temperature exceeding 410 °C, and low α / values. The homogeneous distribution of MGW in the PSR thin film resulted in a notable reduction in its linear expansion coefficient, as well as its thermal diffusion coefficient. Consequently, it exhibited a significant capacity for thermal insulation and retention. For the sample with 5 wt% of MGW, the linear expansion coefficient and thermal diffusion coefficient at 200 °C were reduced to 0.53% and 2.703 mm s −2 , respectively. Thus, the PSR/MGW composite film has good heat-resistance stability and low-temperature endurance, along with low α / values and excellent dimensional stability. Additionally, it facilitates effective thermal insulation and temperature control, and can be an ideal material for thermal control coatings on spacecraft surfaces. Innovative research on the development of thermal control films for spacecraft surfaces is presented.