Particle Analysis

XPS or ESCA Analysis:

  • Determines the surface elemental composition for all elements except hydrogen and helium
  • Determines the chemical phases present both quantitatively and for complex phases
  • Contrasts surface chemistry with interior chemistry either by argon ion sputtering or by fresh grinding
  • Surface chemistry is often very different from the bulk chemistry and dependent upon environment
  • Surface chemistry dominates in reactions with other materials
  • Contaminant detection and identification on surfaces
  • Determine causes of wetting and adhesive bonding problems
  • Determine degree of surface hydration
  • Determine cause of sintering problems
  • Identify fill materials of plastics, composite materials, paints, primers, sealants, thermal compounds, and adhesives after burning off polymer matrix with TGA

SEM Analysis:

  • Views surface morphology
  • Measures particle sizes
  • Provides evidence for uniformity or not
  • Images agglomerated particles well
  • Examine rough surfaces

Optical Microscopy:

  • Checks color uniformity for many particles
  • Checks light transmission and reflection uniformity
  • Suggests the presence of multiple chemistries and sometimes the nature of the differences
  • Determine particle sizes and shapes
  • Determine the distribution of particles in transparent media such as glass and some ceramics and plastics

TGA or Thermogravimetric Analysis:

  • Determines if particles decompose and, if so, at what temperature
  • Often allows quantitative chemical analysis by weight
  • Measure weight of inorganic particles in a polymer matrix, such as plastics, composite materials, paints, primers, sealants, thermal compounds, and adhesives by burning off polymer matrix in air or oxygen
  • Prepares inorganic particles from plastics, etc., for XPS analysis and SEM or optical microscopy

DSC or Differential Scanning Calorimetry Analysis:

  • Measures particle melting temperature and heat of fusion
  • Determines temperature and energy of reaction between particles and another material
  • Measures particle oxidation temperature and energies
  • Measures heat absorption by five retardant fill materials such as aluminum trihydrate or magnesium hydroxide
  • Detects particle structural phase changes
  • Measures the specific heat
  • Measures glass transition temperature of polymer particles

FTIR or Infrared Spectroscopy Analysis:

  • Identifies organic material in particle form or on particles, whether a surface treatment or a contaminant
  • Determines whether carbonates, phosphates, nitrates, nitrites, sulfates, or water are present
  • Identifies organic binders used to consolidate particles in abrasive wheels, cutting discs, brake pads, and other applied materials