Cf-252 particle desorption mass spectrometry of polymer surfaces

Thesis/Dissertation · Sun Jan 01 04:00:00 EST 1989

OSTI ID:7039139

Cf-252 particle desorption mass spectrometry was applied to the analysis of synthetic polymers using the low mass region (m/z < 500). For each polymer, a series of characteristic masses were obtained and compared with results from other mass spectrometric techniques. Structures that can stabilize the charge of the fragment ions produce fingerprinting spectra (e.g. poly(ethylene oxide) and polystyrene). Most polymers produced a series of decomposition peaks assigned to unsaturated ring structures. The polymers produced a series of carbon cluster peaks even if the polymer backbone structure was regularly interrupted by oxygen atoms. Thus carbon cluster formation must involve the recombination of atomized carbon as has been suggested with laser vaporization studies of graphite. The low primary ion fluence of PDMS (10{sup 2} ions/s) mitigates the effects of surface charge-up and damage. He studied the chemical modification of the polystyrene surface caused by photo-oxidation. Peaks from photooxidation products were tentatively assigned to hydroperoxides. Physical modifications were studied using polymer-additive systems. Both additive and polymer produced their characteristic fragmentation patterns. PDMS combined with correlated data acquisition permitted the analysis of a heterogeneous surface. To demonstrate heterogeneity: (1) the excitation spot must be a discrete event of small size (less than micrometers), (2) the peak used for the correlation of events must be unique to the compound, (3) the heterogeneity must be of a size larger than the size of the desorption spot (approximately 20 nm for PDMS).

• Research Organization: Texas A and M Univ., College Station, TX (United States)
• OSTI ID: 7039139
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
400101* -- Activation
Nuclear Reaction
Radiometric &amp; Radiochemical Procedures
400102 -- Chemical &amp; Spectral Procedures
400600 -- Radiation Chemistry
ACTINIDE ISOTOPES
ACTINIDE NUCLEI
ALPHA DECAY RADIOISOTOPES
CALIFORNIUM 252
CALIFORNIUM ISOTOPES
CHARGED PARTICLES
CHEMICAL REACTIONS
CHEMISTRY
DATA
DESORPTION
DYNAMIC MASS SPECTROMETERS
EVEN-EVEN NUCLEI
EXPERIMENTAL DATA
HEAVY NUCLEI
INFORMATION
IONS
ISOTOPES
MASS SPECTROMETERS
MASS SPECTROSCOPY
MATERIALS
MEASURING INSTRUMENTS
NUCLEI
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC POLYMERS
OXIDATION
PARTICLES
PETROCHEMICALS
PETROLEUM PRODUCTS
PHOTOCHEMISTRY
PLASTICS
POLYMERS
POLYOLEFINS
POLYSTYRENE
POLYVINYLS
RADIOISOTOPES
SORPTION
SPECTROMETERS
SPECTROSCOPY
SPONTANEOUS FISSION RADIOISOTOPES
SYNTHETIC MATERIALS
TIME-OF-FLIGHT MASS SPECTROMETERS
TIME-OF-FLIGHT SPECTROMETERS
YEARS LIVING RADIOISOTOPES