In-depth Revelation —— Why Does the Thermal Insulation Performance of Aerogel Fiber Surpass That of Down?

Aerogel is a kind of nanoporous material composed of gas and a solid skeleton, and it is known as “solid smoke”. Due to its excellent thermal insulation performance, it has become the core material of the protective layer in aerospace.

So, what is the principle of aerogel’s thermal insulation?

In fact, it stems from four physical mechanisms:

1. Blocking of thermal radiation. The nanoscale pore walls (20-50nm) form countless “heat shields”, cutting the thermal radiation path into fragmented short-range transmissions. For example, the infrared radiation transmittance of silica aerogel is only 1/5 of that of traditional materials.
2. Suppression of thermal convection. The size of the air holes (<70nm) is smaller than the mean free path of air molecules, and the air inside the holes cannot flow, forming a “quasi-vacuum layer”. Experiments show that the convective heat loss inside the aerogel approaches zero.
3. Blocking of heat conduction. The solid skeleton accounts for only 1%-20% of the material’s volume, and heat needs to be conducted around countless holes, with a circuitous path.
4. Photothermal regulation. Aerogel can achieve dynamic thermal management by regulating the solar reflectance and infrared emissivity. For example, aerogels with high reflectance can reduce the greenhouse effect during the day, while aerogels with low reflectance enhance thermal insulation at night.

Aerogel fiber is formed by the combination of aerogel and carrier polyester. After aerogel imparts its thermal insulation performance to polyester, the performance of aerogel fiber is also remarkable.

As long as the aerogel content in the aerogel fiber exceeds 3%, the thermal insulation effect can comprehensively surpass that of down.

Traditional down relies on a fluffy structure to lock in air to achieve thermal insulation, but aerogel fiber can still maintain its thermal insulation performance in wet and cold environments.

It can be said that aerogel fiber is a miracle in materials science and a new king in textile materials.

Currently, Qingfeng Chemical Fiber is the only company in China that has achieved the significant breakthrough of 3% aerogel content in aerogel fiber. It not only ranks at the forefront of the industry with technological innovation but also promotes the ecological transformation of the textile industry.