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Title of paper
  Development of a new pyrolyzer for TD and/or Py-GC of polymeric materials
C. Watanabe et al., J. High Resolut. Chromatogr. 14 (1991) 269-272

(A new vertical microfurnace-type pyrolyzer for thermal desorption and/or pyrolysis-gas chromatography has been developed. The pyrolyzer consists of two independent temperature-controlled ovens.
Initially, in the desorption process, a sample cup containing the polymeric sample of interest is inserted into an oven at 300ºC the sample is then re-positioned at the upper part of the pyrolyzer where the temperature is maintained at room temperature. The resulting vaporized components such as residual solvents and additives give a desorption chromatogram. The relative peak intensities of desorbed plasticizers in acrylonitrile butadiene-rubber gave a relative standard deviation (RSD) of less than 2%.
Subsequently, pyrolysis of the remaining polymer is conducted by dropping the sample cup into the second, pyrolyzing, oven at 55ºC; at this stage the pyrogram is recorded.
The resulting two chromatograms of desorbed components and pyrolysis products make it easier to characterize the polymer formulation than the complicated pyrogram obtained by an ordinary, single-step pyrolysis. Development of a new pyrolyzer for thermal desorption and/or pyrolysis gas chromatography of polymeric materials C. Watanabe, K. Teraishi, S. Tsuge, H. Ohtani, K. Hashimoto J. High Resolut. Chromatogr., 14 (1991) 269-272 Multi-functional Pyrolyzer prototype)
1991-01
  Pyrolyzer
Application apl_oth,apl_pol,dev_pro
 
 
PSWD --  
Date 199101

 


  Pyrolysis-gas chromatography for end group analysis of polystyrene macromonomers using stepwise pyrolysis combined with on-line methylation H. Ohtaniet et al., J. Anal. Appl. Pyrolysis 25 (1993) 1–10
(Pyrolysis-gas chromatography for end group analysis of polystyrene macromonomers using stepwise pyrolysis combined with on-line methylation
H. Ohtani, S. Ueda, Y. Tsukahara, C. Watanabe, S. Tsuge
J. Anal. Appl. Pyrolysis 25 (1993) 1–10
The end group functionalities of polystyrene macromonomers with methacryloyl (ML) end groups were determined by stepwise pyrolysis-gas chromatography (PyGC) at different temperatures, using a two stage pyrolyser consisting of two independent furnaces, combined with an on-line methylation technique. The macromonomer sample in THF solution was mixed with tetramethylammonium hydroxide in methanol solution, as the methylation reagent, in a sample cup; this was introduced into the first furnace (250ºC) of the pyrolyser attached to a gas chromatograph to decompose selectively the ML end group moieties in the macromonomer to methyl methacrylate (MMA). After GC analysis of the formed MMA, the sample cup was dropped down into the second furnace (650ºC) to pyrolyse the residual polystyrene main chain thoroughly. The concentration of the ML end groups was determined by comparing the peak intensity of MMA observed in the former pyrogram with those of the characteristic products formed from the polystyrene main chain in the latter pyrogram. The end group functionalities of several macromonomer samples calculated from the concentrations of the end groups, determined by PyGC, were in fairly good agreement with those determined by 1H NMR, and with those calculated from the data of the maximum conversion of the macromonomers.
Original equipment)
1993-01
  Pyrolyzer
Application apl_pol
 
 
PSWD --  
Date 199301

 


  Development of Selective Sampler on EGA Using Furnace Type Pyrolyzer
A. Hosaka et al., J. Mass Spectrom. Soc. Jpn. 46 (1998) 332-335

(A novel selective sampling device was proposed for an evolved gas analysis (EGA) method using a temperature programmable pyrolyzer with a GC detector such as mass spectrometer. The new method is based on the indirect flow switching technique free of a direct mechanical valve utilized for conventional EGA systems. This sampling device enabled the selective sample introduction of any desired temperature ranges for the products observed in EGA to the associated detection system. From the observed data for several polar compounds by the measuring system equipped with this sampling device, it was confirmed that the system had little dead volume and less active inner surface. Furthermore, it was demonstrated that the selective introduction of evolved products was successfully applied for the characterization of a complex formulated polymeric material. A novel selective sampling device was proposed for an evolved gas analysis (EGA) method using a temperature programmable pyrolyzer with a GC detector such as mass spectrometer. The new method is based on the indirect flow switching technique free of a direct mechanical valve utilized for conventional EGA systems. This sampling device enabled the selective sample introduction of any desired temperature ranges for the products observed in EGA to the associated detection system. From the observed data for several polar compounds by the measuring system equipped with this sampling device, it was confirmed that the system had little dead volume and less active inner surface. Furthermore, it was demonstrated that the selective introduction of evolved products was successfully applied for the characterization of a complex formulated polymeric material. J. Mass Spectrom. Soc. Jpn., 46 (1998) 332-335 A. Hosaka, K. Sato, C. Watanabe, H. Ohtani, S. Tsuge Multi-functional pyrolyzer, Selective Sampler, UA column)
1998-01
  Pyrolyzer
Application apl_oth,apl_add
 
 
PSWD --  
Date 199801

 


  Determination of Residual Solvents in Bulk Pharmaceuticals by Thermal Desorption/Gas Chromatography/Mass Spectrometry K. URAKAMI et al., Chem. Pharm. Bull. 48 (2000) 1894-1897
(Determination of Residual Solvents in Bulk Pharmaceuticals by Thermal Desorption/Gas Chromatography/Mass Spectrometry
K. URAKAMI, Y. SAITO, Y. FUJIWARA, C. WATANABE, K. UMEMOTO, M. GODO, K. HASHIMOTO
Chem. Pharm. Bull. 48 (2000) 1894-1897
Thermal desorption (TD) techniques followed by capillary GC/MS were applied for the analysis of residual solvents in bulk pharmaceuticals. Solvents desorbed from samples by heating were cryofocused at the head of a capillary column prior to GC/MS analysis. This method requires a very small amount of sample and no sample pretreatment. Desorption temperature was set at the point about 20ºC higher than the melting point of each sample individually. The relative standard deviations of this method tested by performing six consecutive analyses of 8 different samples were 1.1 to 3.1%, and analytical results of residual solvents were in agreement with those obtained by direct injection of N, N-dimethylformamide solution of the samples into the GC. This novel TD/GC/MS method was demonstrated to be very useful for the identification and quantification of residual solvents in bulk pharmaceuticals.
Double-shot pyrolyzer)
2000-01
  Pyrolyzer
Application apl_cnsp
 
 
PSWD --  
Date 200001

 


  Development of a multifunctional pyrolyzer for EGA, TD, and/or Py-GC of polymeric materials
C. Watanabe et al., Am. Lab. October (2001) 14-15

(Using an improved pyrolyzer, an evolved gas analysis by programmed heating and a two-step pytolyzer carrying out thermal desorption and flash pyrolysis as well as conventional flash pyrolysis was performed. Problems frequently encountered in the past were resolved. Development of a multifunctional pyrolyzer for evolved gas analysis, thermal desorption, and/or pyrolysis-GC of polymeric materials C. Watanabe, K. Sato, A. Hosaka, H. Ohtani, S. Tsuge Am. Lab., October (2001) 14-15 Multi-functional Pyrolyzer)
2001-01
  Pyrolyzer
Application apl_oth,apl_pol,dev_pro
 
 
PSWD --  
Date 200101

 


  GC–MS Analysis of Heart-Cut Fractions During EGA of Polymeric Materials
C. Watanabe et al., LCGC North America 20 (2002) 374-378

(The combination of evolved gas analysis, trap-and-purge sampling of desired portions of the evolved fraction (heartcutting), and gas chromatography–mass spectrometry characterization (GC–MS) can be a very powerful method to investigate complex polymeric materials. The authors conducted a preliminary survey by conventional evolved gas analysis and MS total ion detection to select evolution temperature ranges for heart-cut fractions in subsequent GC–MS analyses. In the heart-cut evolved gas analysis with GC–MS analysis, each heart-cut fraction was cryotrapped and analyzed by high-resolution capillary GC–MS. They used MS library searching to identify the components in each fraction and to comprehensively characterize the polymeric materials with regard to substrate polymers and additives such as plasticizers and stabilizers. GC–MS Analysis of Heart-Cut Fractions During Evolved Gas Analysis of Polymeric Materials C. Watanabe, A. Hosaka, Y. Kawahara, P. Tobias, H. Ohtani, S. Tsuge LCGC North America, 20 (2002) 374-378 Multi-functional Pyrolyzer, Selective Sampler, MicroJet Cryo-Trap, UA-5)
2002-01
  Pyrolyzer
Application apl_cnsp
 
 
PSWD --  
Date 200201

 


  Development of pyrolysis-fractography
C. Watanabe et al., J. Anal. Appl. Pyrolysis 64 (2002) 197–205

(Development of pyrolysis-fractography
C. Watanabe, Y. Kawahara, H. Ohtani, S. Tsuge
J. Anal. Appl. Pyrolysis 64 (2002) 197–205
As a novel method for analytical pyrolysis of polymers, pyrolysis-fractography (Py-F) was developed. In this method, the pyrolyzates generated when a polymer is instantaneously pyrolyzed at 600ºC are introduced together with the carrier gas into a short length of deactivated stainless steel capillary tube equipped in the gas chromatographic oven. By a programmed heating the oven temperature is linearly raised, so that the pyrolyzates are fractionated, and a fractogram is obtained using a mass spectrometer or a flame ionization detector. The fundamental study was conducted using polyethylene, and this method was applied to elucidate the pyrolysis behavior of such nitrogen containing polymers as polyurethane and melamine formaldehyde resin. As a result, the Py-F method was proved to be useful in analyzing the pyrolysis behavior of polymeric materials, such as a nitrogen-containing polymer, that generates highly polar components upon pyrolysis.
Multi-functional Pyrolyzer (PY-2020iD), polymer prepper)
2002-02
  Pyrolyzer
Application apl_oth
 
 
PSWD --  
Date 200202

 


  Applications of a Multifunctional Pyrolyzer for EGA and Py-GC of Various Synthetic and Natural Materials: Part 3
S. Tsuge et al., Am. Lab. December (2003) 16-18

(This article is the continuation of a series published in the January and March 2003 issues of American Laboratory. It illustrates the applications of multifunctional pyrolysis for the charac-terization of natural products such as zooplankter and lignin Applications of a Multifunctional Pyrolyzer for Evolved Gas Analysis and Pyrolysis-GC of Various Synthetic and Natural Materials: Part 3 S. Tsuge, H. Ohtani, C. Watanabe Am. Lab., December (2003) 16-18 Multi-functional Pyrolyzer, Ultra ALLOY® columns)
2003-01
  Pyrolyzer
Application apl_cnsp
 
 
PSWD --  
Date 200301

 


  Applications of a multifunctional pyrolyzer for EGA and Py-GC of various synthetic and natural materials
S. Tsuge et al., Am. Lab. January (2003) 32-37

(The applications, characteristics and performance of pyrolysis-gas chromatography (Py-GC) system in characterizing various materials are discussed. This system consists of a multifunctional microfurnace pyrolyzer with a sophisticated temperature-control device and ultrahigh-temperature metal capillary separation columns. The formation of char on the surface of the FR-PC material shields the radiant heat from outside. The results suggests that the crosslinking structure formed during the earlier stage of combustion induced in the presence of the silicone flame retardant might suppress the thermal decomposition of the PC materials at high temperatures. Applications of a multifunctional pyrolyzer for evolved gas analysis and pyrolysis-GC of various synthetic and natural materials S. Tsuge, H. Ohtani, C. Watanabe, Y. Kawahara Am. Lab., January (2003) 32-37 Multi-functional Pyrolyzer, Ultra ALLOY® column)
2003-02
  Pyrolyzer
Application apl_cnsp
 
 
PSWD --  
Date 200302

 


  Applications of a multifunctional pyrolyzer for EGA and Py-GC of various synthetic and natural materials: Part 2
S. Tsuge et al., Am. Lab. March (2003) 48-52

(This article illustrates the recent applications achieved by using the multifunctional pyrolyzer, which was described in the January issue of American Laboratory. Applications of a multifunctional pyrolyzer for evolved gas analysis and pyrolysis-GC of various synthetic and natural materials: Part 2 S. Tsuge, H. Ohtani, C. Watanabe, Y. Kawahara Am. Lab., March (2003) 48-52 Multi-functional Pyrolyzer, Ultra ALLOY® column)
2003-03
  Pyrolyzer
Application apl_cnsp
 
 
PSWD --  
Date 200303

 


  Development of a novel solid-phase extraction element for TD-GC analysis
L. Wang et al., J. Chromatogr. 1035 (2004) 277-279

(A novel solid-phase extraction element is developed for sorptive enrichment of dilute analytes from liquid samples with high extraction efficiencies due to its larger amounts of polydimethylsiloxane (PDMS) absorbent than the conventional syringe type of solid-phase microextraction (SPME).
The extraction element is made of titanium (Ti) open tubular tube (Full-size image (<1 K)) coated with a chemically bonded layer of PDMS (500 μm in thickness). The extraction element combined with thermal desorption–gas chromatography–mass spectrometry using a pyrolysis–gas chromatography–mass spectrometry system was used to extract and analyze a typical herbicide, bethrodine in water samples over a concentration range from 2.5 to 2.5×104 ng/l.
Thus obtained calibration curve showed good linearity for the tested whole concentration range with regression coefficient of 0.992. Detection limit of 0.5 ng/l level was achieved and the reproducibility of the measurements for bethrodine at 10 ng/l level was found to be fairly good with relative standard deviation below 7.5%. Development of a novel solid-phase extraction element for thermal desorption gas chromatography analysis L. Wang, A. Hosaka, C. Watanabe, H. Ohtani, S.Tsuge J. Chromatogr, 1035 (2004) 277-279 Multi-functional Pyrolyzer)
2004-01
  Pyrolyzer
Application apl_cnsp,apl_env,dev_pro
 
 
PSWD --  
Date 200401

 


  Applications of a Multifunctional Pyrolyzer for EGA and Py-GC of Various Synthetic and Natural Materials: Part 4
S. Tsuge et al., Am. Lab. February (2004) 22-26

(This article is the most recent of a series of articles published in the January, March, and December 2003 issues of American Laboratory. It illustrates the application of multifunctional pyrolysis (Py) to the study of the photodegradation of silk and the forensic identification of various denatured oils. Applications of a Multifunctional Pyrolyzer for Evolved Gas Analysis and Pyrolysis-GC of Various Synthetic and Natural Materials: Part 4 S. Tsuge, H. Ohtani, C. Watanabe Am. Lab., February (2004) 22-26 Multi-functional Pyrolyzer)
2004-02
  Pyrolyzer
Application apl_cnsp
 
 
PSWD --  
Date 200402

 


  Development and Application of Pyrolysis Gas Chromatography/Mass Spectrometry for the Analysis of Bound Trinitrotoluene Residues in Soil J.M. Weiss et al., Environ. Sci. Technol. 38 (2004) 2167-2174
(Development and Application of Pyrolysis Gas Chromatography/Mass Spectrometry for the Analysis of Bound Trinitrotoluene Residues in Soil
J.M. Weiss, A.J. McKay, C. DeRito, C. Watanabe, K.A. Thorn, E.L. Madsen
Environ. Sci. Technol. 38 (2004) 2167-2174
TNT (trinitrotoluene) is a contaminant of global environmental significance, yet determining its environmental fate has posed longstanding challenges. To date, only differential extraction-based approaches have been able to determine the presence of covalently bound, reduced forms of TNT in field soils. Here, we employed thermal elution, pyrolysis, and gas chromatography/mass spectrometry (GC/MS) to distinguish between covalently bound and noncovalently bound reduced forms of TNT in soil. Model soil organic matter-based matrixes were used to develop an assay in which noncovalently bound (monomeric) aminodinitrotoluene (ADNT) and diaminonitrotoluene (DANT) were desorbed from the matrix and analyzed at a lower temperature than covalently bound forms of these same compounds. A thermal desorption technique, evolved gas analysis, was initially employed to differentiate between covalently bound and added 15N-labeled monomeric compounds. A refined thermal elution procedure, termed “double-shot analysis” (DSA), allowed a sample to be sequentially analyzed in two phases. In phase 1, all of an added 15N-labeled monomeric contaminant was eluted from the sample at relatively low temperature. In phase 2 during high-temperature pyrolysis, the remaining covalently bound contaminants were detected. DSA analysis of soil from the Louisiana Army Ammunition Plant (LAAP; ∼5000 ppm TNT) revealed the presence of DANT, ADNT, and TNT. After scrutinizing the DSA data and comparing them to results from solvent-extracted and base/acid-hydrolyzed LAAP soil, we concluded that the TNT was a noncovalently bound “carryover” from phase 1. Thus, the pyrolysis-GC/MS technique successfully defined covalently bound pools of ADNT and DANT in the field soil sample.
Multi-functional Pyrolyzer (2020iD))
2004-03
  Pyrolyzer
Application apl_env
 
 
PSWD --  
Date 200403

 


  Rapid Determination of Decabromodiphenyl Ether in Polystyrene by TD-GC/MS
A. Hosaka et al., Anal. Sci. 21 (2005) 1145-1147

(A rapid determination of decabromodiphenyl ether (DeBDE) in polystyrene (PS) by thermal desorption (TD)-GC/MS was studied. The TD-GC/MS method using a pyrolysis-GC/MS system allowed the quick quantification of DeBDE in a waste TV back plate composing of a PS flame-retarded with polybrominated diphenyl ethers on the basis of the resulting chromatogram with a ca. 4% relative standard deviation without using any tedious sample pretreatment, such as solvent extraction. Rapid Determination of Decabromodiphenyl Ether in Polystyrene by Thermal Desorption-GC/MS A. Hosaka, C. Watanabe, S. Tsuge Anal. Sci., 21 (2005) 1145-1147 Multi-functional Pyrolyzer, UADTM-2.5N, UA-PBDE)
2005-01
  Pyrolyzer
Application apl_add.apl_cnsp
 
 
PSWD --  
Date 200501

 


  Development of a new "flow-through" sample cup to reduce undesirable secondary reactions and band broadening of resulting pyrolyzates A. Hosaka et al., J. Anal. Appl. Pyrolysis 78 (2007) 452-455
(When a vertical micro-furnace pyrolyzer is adopted for pyrolysis-gas chromatography (Py-GC), the sample is usually introduced into the center of the preheated pyrolysis chamber by mounting it in a small cylindrical sample cup with a dead-end bottom having a volume of a few dozens micro liters which in some case might be responsible for a stagnant flow of carrier gas in the pyrolysis chamber to cause undesirable secondary reactions of the resulting pyrolyzates and/or peak broadening phenomenon. In order to quench the dead-end flow, a new “flow-through” sample cup in which a small hole (ca. 1.0 mm i.d.) was drilled through its bottom was developed, and its basic characteristics were first examined by measuring the pyrogram of polycarbonate (PC) at 600ºC under different carrier gas flow rates. Various secondary products such as phenol and p-isopropenyl phenol derived from bisphenol A, the main pyrolyzatate of PC were observed when the conventional sample cup without the hole was used under a relatively lower flow rate as 25 ml/min. However, they were markedly decreased when the “flow-through” sample cup was used. Furthermore, the resolution of the lower boiling point pyrolyzates (C1–C8) from high density polyethylene (HDPE) was also much improved by use of the “flow-through” sample cup. Development of a new ‘‘flow-through’’ sample cup for the vertical micro-furnace pyrolyzer to reduce undesirable secondary reactions and band broadening of resulting pyrolyzates A. Hosaka, C. Watanabe, S. Tsuge J. Anal. Appl. Pyrolysis 78 (2007) 452–455 Multi-functional Pyrolyzer, UA+-5, Flow-through Eco-Cup LHF)
2007-01
  Pyrolyzer
Application dev_pro
 
 
PSWD --  
Date 200701

 





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