Analytical Characterization
Thermogravimetric Analysis (TGA)
Differential scanning calorimetry (DSC – crystallization and glass transition properties)
Carbon, hydrogen, nitrogen, oxygen, sulfur (CHNOS) combustion analysis*
Acid digestion for metals analysis
Dynamic shear rheometer
Optical microscopy (transmitted, reflected, cross polarized and fluorescence)
Atomic force microscopy
Molecular Characterization
Fourier transform infrared spectroscopy (FTIR)
Solution, ATR, KBr
Ultraviolet-visible spectroscopy (VU-vis)
Fluorescence spectroscopy
Proton nuclear magnetic resonance spectroscopy (1H NMR)
Carbon nuclear magnetic resonance spectroscopy (13C NMR)
Phosphorous nuclear magnetic resonance spectroscopy (31P NMR): oxygen O-H quantification of alcohols, phenols and carboxylic
Raman spectroscopy
Gas chromatography mass spectroscopy (GCMS)
Gas chromatography (GC)
High temperature GC for waxes
Simulated distillation (SimDis, ASTM D2887)
Size exclusion chromatography
Open column chromatography
Saturates, Aromatics, Resins – Asphaltene Determinator (SAR-AD)
Laser desorption ionization mass spectroscopy
TGA provides quantification of the volatiles, pyrolysis carbon, fixed carbon/carbon residue/coking index and inorganic ash. It can also be used with different gas environments which is helpful in determining the oxidation properties of carbon materials which must undergo oxidative stabilization prior to carbonization.
DSC provides information about crystallization and melt events, as well as glass transition properties. For pitch materials the glass transition can be directly correlated to the softening point of the material. This is important for carbon fiber spinning and also production of pitch based foams.
FTIR is useful for determine functional group types in carbon based materials. It can also provide semi-quantitative information about the functional groups and aromaticity. It is very adept for understanding oxidation stabilization, or other processes, for rates and mechanisms. Spectra can also be used for fingerprinting of materials and used in conjunction with chemomechanical modeling or machine learning to predict performance of materials or the effects of processing conditions.
Fluorescence spectroscopy is a highly sensitive technique which can be used to fingerprint materials. For carbonaceous materials it can provide information about the size of fused aromatic ring systems. The evolution of fused aromatic rings can be tracked during thermal processing to produce larger aromatic ring systems.
Due to the complexity of many carbonaceous materials they are often classified by bulk properties. For better characterization, this method separates carbonaceous materials into similar classes of chemical compounds. The method is useful for fingerprinting, diagnosing process issues and optimization of materials, formulations and processes. When used in conjunction with chemomechanical modeling or machine learning the method provides powerful predictive capabilities. Several SAR-ADTM systems have been licensed to universities and research centers throughout the world. This patented and proprietary method is built on an HPLC system.
This method is suited for rapid determination of exact molecular weights of aromatic carbonaceous materials up to several thousand Daltons. It can be applied to materials which can be dissolved and it can also be applied to insoluble samples in powdered form. In the absence of aromatic cores, or for materials with with other interacting functional groups, the method can be modified to include a matrix to assist ionization.