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Applications of pyrolysis gas chromatography/mass spectrometry for the analysis ofpolymeric samples

Posted on:2000-09-15Degree:Ph.DType:Dissertation
University:University of South CarolinaCandidate:Kochanowski, Brian KeithFull Text:PDF
GTID:1461390014461939Subject:Chemistry
Abstract/Summary:
This dissertation focuses on the applications of pyrolysis gas chromatography/mass spectrometry (py-GC/MS) for the analysis of polymer samples. Pyrolysis applies heat to reduce the polymer to smaller fragments more amenable to analysis by GC/MS. Analysis of these fragments is useful for characterization of polymer structure.; Breath analysis is a non-invasive method for the investigation of the volatile compounds present in human breath. We have developed a methodology using solid phase microextraction (SPME) and capillary gas chromatography for the analysis of various compounds in human breath. Results show that SPME-GC analysis of breath is a simple and accurate method.; Application of principal component analysis (PCA) and canonical variates analysis (CVA) to the chromatograms from the pyrolysis of poly(styrene:acrylate) based toners produced characteristic peaks relevant to differentiation. Our results demonstrate that py-GC/MS is a useful tool for characterization of copied or laser printed documents.; Pyrolysis gas chromatography (Py-GC) has been the standard method for the analysis of automotive paint samples for a number of decades. Pattern recognition techniques such as PCA and CVA were used to assess the statistical validity of differences observed between different samples. Results show that multivariate data analysis techniques can be used to effectively categorize various automotive paint samples.; A quantitative py-GC/MS method using principal component regression (PCR) was developed. Synthetic copolymers are often analyzed using only the ratios of monomer peaks. By using all of the information present in the chromatogram, a more accurate measurement of the composition of the synthetic copolymer can be performed.; Two different fast GC techniques were investigated for the purposes of obtaining faster run times: fast temperature programming and using small internal diameter (ID) columns. These fast GC techniques were applied for pyrolysis of polymeric samples. Both fast temperature programming and small ID columns proved useful for reducing run times while providing the same amount of information as the longer run times obtained using standard capillary columns.
Keywords/Search Tags:Pyrolysis gas, Samples, Polymer, Run times, Using
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