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Fernanda M B Coutinho - One of the best experts on this subject based on the ideXlab platform.

  • mechanical properties of polymer composites based on commercial epoxy vinyl ester resin and glass fiber
    Polymer Testing, 2001
    Co-Authors: A Nazareth L Da Silva, A C C Widal, Sylvia C. S. Teixeira, Fernanda M B Coutinho
    Abstract:

    Abstract The effect of the addition of methyl ethyl ketone peroxide (MEKP) and cobalt naphthenate (CoNaph) on the mechanical behavior of epoxy vinyl ester resin (EVER) laminates has been investigated by using a factorial experimental design, in which the MEKP and NaphCo contents were varied. Previous results showed that there is an interaction effect between the process variables analysed on the mechanical properties evaluated. It was also observed that the MEKP/CoNaph ratio affected the tensile behavior of the EVER/glass fiber composites.

  • mechanical properties of polymer composites based on commercial epoxy vinyl ester resin and glass fiber
    Polymer Testing, 2001
    Co-Authors: A Nazareth L Da Silva, A C C Widal, Sylvia C. S. Teixeira, Fernanda M B Coutinho
    Abstract:

    Abstract The effect of the addition of methyl ethyl ketone peroxide (MEKP) and cobalt naphthenate (CoNaph) on the mechanical behavior of epoxy vinyl ester resin (EVER) laminates has been investigated by using a factorial experimental design, in which the MEKP and NaphCo contents were varied. Previous results showed that there is an interaction effect between the process variables analysed on the mechanical properties evaluated. It was also observed that the MEKP/CoNaph ratio affected the tensile behavior of the EVER/glass fiber composites.

Chi-min Shu - One of the best experts on this subject based on the ideXlab platform.

  • Evaluation of adiabatic runaway reaction of methyl ethyl ketone peroxide by DSC and VSP2
    Journal of Thermal Analysis and Calorimetry, 2011
    Co-Authors: Yu-chuan Liang, Can-yong Jhu, Sun-ju Shen, Chi-min Shu
    Abstract:

    Methyl ethyl ketone peroxide (MEKPO) is generally applied to manufacturing in the polymerization processes. Due to thermal instability and high exothermic behaviors of MEKPO, if any operation is undertaken recklessly or some environmental effect is produced suddenly during the processes, fires and explosions may inevitably occur. In this study, thermal analysis was evaluated for MEKPO by differential scanning calorimetry (DSC) test. Vent sizing package 2 (VSP2) was used to analyze the thermal hazard of MEKPO under various stirring rates in a batch reactor. Thermokinetic and safety parameters, including exothermic onset temperature ( T _0), maximum temperature ( T _max), maximum pressure ( P _max), self-heating rate (d T d t ^−1), pressure rise rate (d P d t ^−1), and so on, were discovered to identify the safe handling situation. The stirring rates of reactor were confirmed to affect runaway and thermal hazard characteristics in the batch reactor. If the stirring rate was out of control, it could soon cause a thermal hazard in the reactor.

  • Evaluation of adiabatic runaway reaction of methyl ethyl ketone peroxide by DSC and VSP2
    Journal of Thermal Analysis and Calorimetry, 2011
    Co-Authors: Yu-chuan Liang, Can-yong Jhu, Sun-ju Shen, Chi-min Shu
    Abstract:

    Abstract Methyl ethyl ketone peroxide (MEKPO) is generally applied to manufacturing in the polymerization processes. Due to thermal instability and high exothermic behaviors of MEKPO, if any operation is undertaken recklessly or some environmental effect is produced suddenly during the processes, fires and explosions may inevitably occur. In this study, thermal analysis was evaluated for MEKPO by differential scanning calorimetry (DSC) test. Vent sizing package 2 (VSP2) was used to analyze the thermal hazard of MEKPO under various stirring rates in a batch reactor. Thermokinetic and safety parameters, including exothermic onset temperature (T0), maximum temperature (Tmax), maximum pressure (Pmax), self-heating rate (dT dt−1), pressure rise rate (dP dt−1), and so on, were discovered to identify the safe handling situation. The stirring rates of reactor were confirmed to affect runaway and thermal hazard characteristics in the batch reactor. If the stirring rate was out of control, it could soon cause a the...

  • Isothermal kinetic evaluation of methyl ethyl ketone peroxide mixed with acetone by TAM III tests
    Thermochimica Acta, 2010
    Co-Authors: J.m. Tseng, Chi-min Shu
    Abstract:

    Abstract Methyl ethyl ketone peroxide (MEKPO), the topic material, has been extensively applied as an initiator and cross-linker during polymerization, but it has also induced many severe accidents on a global scale. Therefore, the purpose of this study was to deeply understanding the basic characteristics of runaway reactions of MEKPO and mixed with acetone. The innovative objective of an isothermal kinetic evaluation is to determine the basic characteristics of reactive chemicals in order to prevent a serious runaway accident. Therefore, we endeavored to demonstrate the reaction model and kinetic parameters, such as activation energy (Ea), frequency factor (A), and so on, by the thermal activity monitor III (TAM III) under three isothermal conditions of 70, 80, and 90 °C, in terms of MEKPO 31 mass% and with acetone 99 mass%. The results showed that MEKPO could liberate a great quantity of heat during exothermic reaction. Moreover, acetone could alleviate the degree of exothermic runaway while being added with MEKPO.

  • Thermal explosion analysis of methyl ethyl ketone peroxide by non-isothermal and isothermal calorimetric applications.
    Journal of Hazardous Materials, 2009
    Co-Authors: Jen-hao Chi, Chi-min Shu
    Abstract:

    Abstract In the past, process incidents attributed to organic peroxides (OPs) that involved near misses, over-pressures, runaway reactions, and thermal explosions occurred because of poor training, human error, incorrect kinetic assumptions, insufficient change management, and inadequate chemical knowledge in the manufacturing process. Calorimetric applications were employed broadly to test organic peroxides on a small-scale because of their thermal hazards, such as exothermic behavior and self-accelerating decomposition in the laboratory. In essence, methyl ethyl ketone peroxide (MEKPO) is highly reactive and exothermically unstable. In recent years, it has undergone many thermal explosions and runaway reaction incidents in the manufacturing process. Differential scanning calorimetry (DSC), vent sizing package 2 (VSP2), and thermal activity monitor (TAM) were employed to analyze thermokinetic parameters and safety index. The intent of the analyses was to facilitate the use of various auto-alarm equipments to detect over-pressure, over-temperature, and hazardous materials leaks for a wide spectrum of operations. Results indicated that MEKPO decomposition is detected at low temperatures (30–40 °C), and the rate of decomposition was shown to exponentially increase with temperature and pressure. Determining time to maximum rate (TMR), self-accelerating decomposition temperature (SADT), maximum temperature (Tmax), exothermic onset temperature (T0), and heat of decomposition (ΔHd) was essential for identifying early-stage runaway reactions effectively for industries.

  • Thermal explosion analysis of methyl ethyl ketone peroxide by non-isothermal and isothermal calorimetric applications.
    Journal of hazardous materials, 2009
    Co-Authors: Jen-hao Chi, Chi-min Shu
    Abstract:

    In the past, process incidents attributed to organic peroxides (OPs) that involved near misses, over-pressures, runaway reactions, and thermal explosions occurred because of poor training, human error, incorrect kinetic assumptions, insufficient change management, and inadequate chemical knowledge in the manufacturing process. Calorimetric applications were employed broadly to test organic peroxides on a small-scale because of their thermal hazards, such as exothermic behavior and self-accelerating decomposition in the laboratory. In essence, methyl ethyl ketone peroxide (MEKPO) is highly reactive and exothermically unstable. In recent years, it has undergone many thermal explosions and runaway reaction incidents in the manufacturing process. Differential scanning calorimetry (DSC), vent sizing package 2 (VSP2), and thermal activity monitor (TAM) were employed to analyze thermokinetic parameters and safety index. The intent of the analyses was to facilitate the use of various auto-alarm equipments to detect over-pressure, over-temperature, and hazardous materials leaks for a wide spectrum of operations. Results indicated that MEKPO decomposition is detected at low temperatures (30-40 degrees C), and the rate of decomposition was shown to exponentially increase with temperature and pressure. Determining time to maximum rate (TMR), self-accelerating decomposition temperature (SADT), maximum temperature (T(max)), exothermic onset temperature (T(0)), and heat of decomposition (DeltaH(d)) was essential for identifying early-stage runaway reactions effectively for industries.

Jimmie C Oxley - One of the best experts on this subject based on the ideXlab platform.

  • reactions of organic peroxides with alcohols in atmospheric pressure chemical ionization the pitfalls of quantifying triacetone triperoxide tatp
    Journal of the American Society for Mass Spectrometry, 2018
    Co-Authors: Kevin Colizza, Alexander Yevdokimov, Lindsay Mclennan, James L Smith, Jimmie C Oxley
    Abstract:

    Over the last several decades, mass spectrometry has become one of the principle methods for compound identification and quantification. While for analytical purposes, fragments which are not fully characterized in terms of origin and intensity as a function of experimental conditions have been used, understanding the nature of those species is very important. Herein we discuss such issues relative to triacetone triperoxide (TATP) and its frequently observed fragment at m/z 89. This “fragment” has been identified as the gas-phase reaction product of TATP with one or two methanol molecules/ions. Additionally, the origin and conditions of other fragments at m/z 91, 75, and 74 associated with TATP will be addressed. Similar analytical issues associated with other multi-peroxide organic compounds [hexamethylene triperoxide diamine (HMTD), methyl ethyl ketone peroxides (MEKP)] will also be discussed. Solution storage conditions for TATP, HMTD, and tetramethylene diperoxide diamine dialdehyde have been determined.

  • Reactions of Organic Peroxides with Alcohols in Atmospheric Pressure Chemical Ionization—the Pitfalls of Quantifying Triacetone Triperoxide (TATP)
    Journal of The American Society for Mass Spectrometry, 2018
    Co-Authors: Kevin Colizza, Alexander Yevdokimov, Lindsay Mclennan, James L Smith, Jimmie C Oxley
    Abstract:

    Over the last several decades, mass spectrometry has become one of the principle methods for compound identification and quantification. While for analytical purposes, fragments which are not fully characterized in terms of origin and intensity as a function of experimental conditions have been used, understanding the nature of those species is very important. Herein we discuss such issues relative to triacetone triperoxide (TATP) and its frequently observed fragment at m/z 89. This “fragment” has been identified as the gas-phase reaction product of TATP with one or two methanol molecules/ions. Additionally, the origin and conditions of other fragments at m/z 91, 75, and 74 associated with TATP will be addressed. Similar analytical issues associated with other multi-peroxide organic compounds [hexamethylene triperoxide diamine (HMTD), methyl ethyl ketone peroxides (MEKP)] will also be discussed. Solution storage conditions for TATP, HMTD, and tetramethylene diperoxide diamine dialdehyde have been determined. Graphical Abstract ᅟ

A Nazareth L Da Silva - One of the best experts on this subject based on the ideXlab platform.

  • mechanical properties of polymer composites based on commercial epoxy vinyl ester resin and glass fiber
    Polymer Testing, 2001
    Co-Authors: A Nazareth L Da Silva, A C C Widal, Sylvia C. S. Teixeira, Fernanda M B Coutinho
    Abstract:

    Abstract The effect of the addition of methyl ethyl ketone peroxide (MEKP) and cobalt naphthenate (CoNaph) on the mechanical behavior of epoxy vinyl ester resin (EVER) laminates has been investigated by using a factorial experimental design, in which the MEKP and NaphCo contents were varied. Previous results showed that there is an interaction effect between the process variables analysed on the mechanical properties evaluated. It was also observed that the MEKP/CoNaph ratio affected the tensile behavior of the EVER/glass fiber composites.

  • mechanical properties of polymer composites based on commercial epoxy vinyl ester resin and glass fiber
    Polymer Testing, 2001
    Co-Authors: A Nazareth L Da Silva, A C C Widal, Sylvia C. S. Teixeira, Fernanda M B Coutinho
    Abstract:

    Abstract The effect of the addition of methyl ethyl ketone peroxide (MEKP) and cobalt naphthenate (CoNaph) on the mechanical behavior of epoxy vinyl ester resin (EVER) laminates has been investigated by using a factorial experimental design, in which the MEKP and NaphCo contents were varied. Previous results showed that there is an interaction effect between the process variables analysed on the mechanical properties evaluated. It was also observed that the MEKP/CoNaph ratio affected the tensile behavior of the EVER/glass fiber composites.

Kevin Colizza - One of the best experts on this subject based on the ideXlab platform.

  • reactions of organic peroxides with alcohols in atmospheric pressure chemical ionization the pitfalls of quantifying triacetone triperoxide tatp
    Journal of the American Society for Mass Spectrometry, 2018
    Co-Authors: Kevin Colizza, Alexander Yevdokimov, Lindsay Mclennan, James L Smith, Jimmie C Oxley
    Abstract:

    Over the last several decades, mass spectrometry has become one of the principle methods for compound identification and quantification. While for analytical purposes, fragments which are not fully characterized in terms of origin and intensity as a function of experimental conditions have been used, understanding the nature of those species is very important. Herein we discuss such issues relative to triacetone triperoxide (TATP) and its frequently observed fragment at m/z 89. This “fragment” has been identified as the gas-phase reaction product of TATP with one or two methanol molecules/ions. Additionally, the origin and conditions of other fragments at m/z 91, 75, and 74 associated with TATP will be addressed. Similar analytical issues associated with other multi-peroxide organic compounds [hexamethylene triperoxide diamine (HMTD), methyl ethyl ketone peroxides (MEKP)] will also be discussed. Solution storage conditions for TATP, HMTD, and tetramethylene diperoxide diamine dialdehyde have been determined.

  • Reactions of Organic Peroxides with Alcohols in Atmospheric Pressure Chemical Ionization—the Pitfalls of Quantifying Triacetone Triperoxide (TATP)
    Journal of The American Society for Mass Spectrometry, 2018
    Co-Authors: Kevin Colizza, Alexander Yevdokimov, Lindsay Mclennan, James L Smith, Jimmie C Oxley
    Abstract:

    Over the last several decades, mass spectrometry has become one of the principle methods for compound identification and quantification. While for analytical purposes, fragments which are not fully characterized in terms of origin and intensity as a function of experimental conditions have been used, understanding the nature of those species is very important. Herein we discuss such issues relative to triacetone triperoxide (TATP) and its frequently observed fragment at m/z 89. This “fragment” has been identified as the gas-phase reaction product of TATP with one or two methanol molecules/ions. Additionally, the origin and conditions of other fragments at m/z 91, 75, and 74 associated with TATP will be addressed. Similar analytical issues associated with other multi-peroxide organic compounds [hexamethylene triperoxide diamine (HMTD), methyl ethyl ketone peroxides (MEKP)] will also be discussed. Solution storage conditions for TATP, HMTD, and tetramethylene diperoxide diamine dialdehyde have been determined. Graphical Abstract ᅟ