Properties of laminated silica aerogel fibrous matting composites for footwear applications

Abstract

This paper describes a lamination method of commercially produced silica aerogel composite and investigates its suitability for thermal insulation within protective footwear applications for severe cold and extreme high-altitude environments. A silica aerogel composite was used with a thickness of 2.7 mm and mass per unit area of 500 gm–2. Silica aerogel dust, which is generated during the crushing of brittle silica aerogel, was prevented from spreading into the environment by two-sided lamination of silica aerogel composite. A solid 5 µm thick membrane was used, reinforced with an abrasive resistant polyester knitted fabric. The thermal conductivity of laminated silica aerogel composite was comparable to that of the non-laminated one and amounted to 0.016 Wm–1K–1. Water vapor permeability of the laminated silica aerogel composite was 1.31 mgcm–2h–1. The silica aerogel composite was subjected to 30,000 cycles of flexing in order to study the impact of its irreversible crushed structure on the water vapor permeability and thermal resistances of laminated samples. It was observed that flexing did not damage the membrane of the laminated composite and had no statistically significant effect on its thermal resistance and water vapor permeability. During this study it was confirmed that the newly developed laminate has potential applications within protective footwear for extreme cold temperature environments.

Application of Silica Aerogel in Composites Protecting Against Thermal Radiation

“…Aerogel crushing during a test simulating the real use of footwear material was observed by Kraner et al [31]. Those researchers studied silica aerogel composites made from a silica aerogel matrix embedded in a noncombustible reinforced fibrous matting material and laminated with a polyetherester block copolymer membrane.…”

“…Silica aerogel dust (>100 nm) arose from the broken particles of aerogel which migrated from the inner part of the composite to its surface. According to Kraner et al [31], a lamination was an appropriate method for the preparation of aerogel composites for footwear applications.…”

Multilayer Nonwoven Inserts with Aerogel/PCMs for the Improvement of Thermophysiological Comfort in Protective Clothing against the Cold

“…The problem of crushing aerogel particles is well known. This was pointed out by Kraner Zrim et al [ 58 ], researching a laminated silica aerogel composite in terms of its suitability as thermal insulation in footwear protecting against the cold. The material was subjected to 30,000 bending cycles to simulate real conditions of use.…”

Wearable Aerogels for Personal Thermal Management and Smart Devices

“…The pioneering applications of wearable aerogels based on silica aerogel composites date back decades: however, they possessed limited mechanical flexibility and breathability. − In 2022, Zhang et al presented a noteworthy development, an ultralight and hyperelastic SiC nanofiber aerogel designed for personal thermal energy regulation . Nonetheless, its wearability was limited by mechanical weakness.…”