6 Materialchemie
Filtern
Erscheinungsjahr
- 2020 (12) (entfernen)
Dokumenttyp
Sprache
- Englisch (12)
Schlagworte
- Biofilm (2)
- Iron oxide nanoparticles (2)
- Silver nanoparticle (2)
- Starch (2)
- Starch nanoparticle (2)
- 2PP (1)
- 3D-printing (1)
- AISI 304L (1)
- ATZ (1)
- Additive Manufacturing (1)
- Additive manufacturing (1)
- Alpha-tricalcium phosphate (1)
- Alumina toughened zirconia (1)
- Atom probe tomography (1)
- Bacterial attachment (1)
- Binder Jetting (1)
- Ceramic nano particles (1)
- Degradation signatures (1)
- Deuterium (1)
- EBSD (1)
- Electron microscopy (1)
- Fuel sorption (1)
- Gas flow assisted powder deposition (1)
- High density polyethylene (1)
- High entropy alloy (1)
- Hydrogen (1)
- Imaging techniques (1)
- Metal and alloys (1)
- Nano-ceramic-additive-manufacturing photoresin (1)
- NanoCAM (1)
- Nanomaterials (1)
- Nanoparticles (1)
- Nanoplattform (1)
- Particle size (1)
- Polymer analysis/characterization (1)
- Reference material (1)
- Reference nanomaterials (1)
- Reliable characterization (1)
- Scaffold (1)
- SchwarzP cells (1)
- Size and size distribution (1)
- Slurry (1)
- Thermal desorption mass spectrometry (1)
- Thermoset composition (1)
- ToF-SIMS (1)
- Transmission electron microscopy (1)
- Two-photon polymerization (1)
- UV-irradiation (1)
- Volatiles from thermosets (1)
- Volume specific surface area (1)
- X-ray diffraction (1)
Organisationseinheit der BAM
- 5 Werkstofftechnik (12) (entfernen)
Eingeladener Vortrag
- nein (1)
Thermoset materials characterization is often limited to solid state analytical techniques such as IR, NMR, DSC, TGA and mechanical testing. Alternatively, their off-gassing behavior can also be evaluated using GC based techniques such as TD-GC-MS, allowing this method to be applied to thermoset materials analyses such as identification, aging characterization, and formulation optimization. As an overview, common thermoset materials were evaluated by analyzing their gaseous degradation products via TGA-based pyrolysis and subsequent TD-GC-MS for the identification of representative volatile signatures. It is thereby possible to distinguish different classes of phenolic materials or cured epoxy resins, as well as their amine or anhydride curatives. Additionally, this method enabled quantification of a volatile fragment (bisphenol A, BPA) which is associated with oxidation of epoxy/amine thermoset materials. The amount of evolved BPA increased linearly with aging time and this trend exhibits linear Arrhenius behavior over the temperature range (80–125 °C) studied, in agreement with oxidation sensitivies based on oxygen consumption data. Further, TD-GC-MS was used to explore how off-gassing of residual anhydride curative from an epoxy/anhydride material depends on formulation stoichiometry. Even in formulations that theoretically contained enough epoxy to consume all anhydride (1:1 stoichiometry), an imperfect final cure state resulted in residual anhydride which could evolve from the material. For such materials, a slightly epoxy-rich formulation is required to ensure that the material contains no residual unreacted anhydride. Analysis of volatiles generated by thermal exposure is an attractive characterization approach enabling compositional analysis as well as complementary diagnostics for materials degradation.
This chapter first gives an introduction to the concepts of SSA and volume-specific surface area (VSSA) and an outline of the BET method. It continues with a discussion of the relationship between particle size, shape, and the VSSA, followed by an overview of instrumentation, experimental methods, and standards. Finally, sections on the use of the VSSA as a tool to identify nanomaterials and non-nanomaterials and its role in a regulatory context provide some insight on the importance of VSSA in the current Regulation of nanomaterials.