Formula analysis and testing procedures, methods and testing items for Aerogel
Aerogel is a highly dispersed amorphous solid material composed of colloidal particles or polymer molecules aggregated together to form a nanoporous network structure, and the pores are filled with gaseous dispersion medium. Aerogel, also known as xerogel, is a gel obtained by reacting a chemical solution to form a sol first, and then gelling. After removing the solvent in the gel, a spatial network structure is obtained that is filled with gas. The appearance A porous material with extremely low density (close to air density) in solid form.
Aerogels are ultra-lightweight, low-density, nanoporous, characterized by ultra-fine honeycomb pore sizes and porous structures made up of interconnected polymeric chains. Pore diameters are typically less than 100 nm, and aerogel particle sizes are typically less than 20 nm. It can be made of inorganic materials (such as silica, alumina, etc.), organic materials (such as polyimide, carbon, etc.), or mixed materials (such as gel glass, etc.).
Aerogels can be divided into 4 categories according to the chemical properties of their matrix: inorganic aerogels, organic aerogels, hybrid aerogels, and composite aerogels.
<<Common sample composition analysis process>>
① Sample preparation: Select representative samples and perform necessary preprocessing, such as sample grinding, dissolution, dilution, etc., to ensure the representativeness and operability of the analysis.
② Analysis methods: Generally, various instruments such as infrared spectroscopy, nuclear magnetic resonance spectroscopy, GC-MS, PY-GC-MS, ICP, IC, HPLC, XPF, and GPC are used.
③ Instrument testing: According to the selected analysis method, prepare and debug the corresponding instruments and equipment, and perform calibration and calibration to ensure the accuracy and stability of the instrument.
④ Sample measurement: Verify the analysis results in many aspects by combining spectrum analysis, common methods of basic chemistry and related characteristic verification.
⑤ Data processing: Perform data processing on the measured raw data, such as peak identification, peak area or peak height integration, etc., to obtain quantitative results of each component.
⑥ Result report: Based on the analysis results, evaluate and explain the measured material components, determine its content, purity or different related indicators, and write a report.
<<Common analysis and testing methods>>
Qualitative analysis of polymers and organic additives requires spectral (infrared, nuclear magnetic, ultraviolet absorption, etc.) detection methods;
The inorganic elements can be tested through electron microscopy/X-ray energy spectroscopy, X-ray fluorescence spectrometer, plasma emission spectrometry, etc.;
For qualitative analysis of inorganic compounds, methods such as infrared, Raman or X-ray diffraction can be used;
Quantitative analysis of samples can be accomplished by chemical analysis or atomic absorption spectroscopy and plasma emission spectroscopy.
<<Routine testing items for aerogel composite insulation products>>
Thermal conductivity is the most important testing index for airgel composite insulation products and one of the basis for its classification.
The combustion performance requirements of type I airgel composite insulation products shall not be lower than B1 (C) level, and the combustion performance requirements of type II, III and IV gel composite insulation products shall not be lower than A (A2) level.
In terms of heating permanent line change index, type I, type II and type III gel composite insulation products are required to be no less than -2.0%, while type IV gel composite insulation products are required to be no less than -5.0%.
The vibration mass loss rate is required not to be greater than 1.0%.