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T D Tran - One of the best experts on this subject based on the ideXlab platform.

  • Physical Characterization of RX-55-AE-5 a Formulation of 97.5 % 2,6-Diamino-3,5-Dinitropyrazine-1-Oxide (LLM-105) and 2.5% Viton A Physical Characterization of RX-55-AE-5 A Formulation of 97.5 % 2,6-Diamino-3,5-Dinitropyrazine-1-Oxide (LLM-105) and 2.5% V
    2020
    Co-Authors: R K Weese, A K Burnham, H C Turner, T D Tran
    Abstract:

    ABSTRACT With the use of modern tools such as molecular modeling on increasingly powerful computers, new materials can be evaluated by their structural activity relationships, SAR, and their approximate physical and chemical properties can be calculated in some cases with surprising accuracy. These new capabilities enable streamlined synthetic routes based on safety, performance and processing requirements, to name a few [1]. Current work includes both understanding properties of old explosives and measuring properties of new ones. The necessity to know and understand the properties of energetic materials is driven by the need to improve performance and enhance stability to various stimuli, such as Thermal, friction and impact insult. This review will concentrate on the physical properties of RX-55-AE-5, which is formulated from heterocyclic explosive, 2,6-diamino-3,5-dinitropyrazine-1-oxide, LLM-105, and 2.5 % Viton A. Differential scanning calorimetry, DSC, was used to measure a specific heat capacity, for mass loss in an open pan. Thermal Mechanical Analysis, TMA, was used to measure the coefficient of Thermal expansion, CTE. The CTE for this formulation was calculated to be ≈ 61 µm/m•˚C. Impact, spark, friction and evolved gases are also reported

  • physical characterization of rx 55 ae 5 a formulation of 97 5 2 6 diamino 3 5 dinitropyrazine 1 oxide llm 105 and 2 5 viton a
    Presented at: North American Thermal Analysis Society 33rd Annual Conference Universal City CA United States Sep 19 - Sep 21 2005, 2005
    Co-Authors: R K Weese, A K Burnham, H C Turner, T D Tran
    Abstract:

    With the use of modern tools such as molecular modeling on increasingly powerful computers, new materials can be evaluated by their structural activity relationships, SAR, and their approximate physical and chemical properties can be calculated in some cases with surprising accuracy. These new capabilities enable streamlined synthetic routes based on safety, performance and processing requirements, to name a few [1]. Current work includes both understanding properties of old explosives and measuring properties of new ones. The necessity to know and understand the properties of energetic materials is driven by the need to improve performance and enhance stability to various stimuli, such as Thermal, friction and impact insult. This review will concentrate on the physical properties of RX-55-AE-5, which is formulated from heterocyclic explosive, 2,6-diamino-3,5-dinitropyrazine-1-oxide, LLM-105, and 2.5% Viton A. Differential scanning calorimetry, DSC, was used to measure a specific heat capacity, C{sub p}, of {approx} 0.950 J/g {center_dot} C, and a Thermal conductivity, {kappa}, of {approx} 0.160 W/m {center_dot} C. The Lawrence Livermore National Laboratory (LLNL) code Kinetics05 and the Advanced Kinetics and Technology Solutions (AKTS) code Thermokinetics were both used to calculate Arrhenius kinetics for decomposition of LLM-105. Both obtained an activation energy barrier E {approx} 180 kJ mol{supmore » -1} for mass loss in an open pan. Thermal Mechanical Analysis, TMA, was used to measure the coefficient of Thermal expansion, CTE. The CTE for this formulation was calculated to be {approx} 61 {micro}m/m {center_dot} C. Impact, spark, friction and evolved gases are also reported.« less

Erwin Freund - One of the best experts on this subject based on the ideXlab platform.

  • mechanistic studies of glass vial breakage for frozen formulations i vial breakage caused by crystallizable excipient mannitol
    Pda Journal of Pharmaceutical Science and Technology, 2007
    Co-Authors: Ge Jiang, Mike Akers, Manish Jain, Adrian Distler, Rob Swift, Manpreetvick S Wadhwa, Feroz Jameel, Sugu Patro, Erwin Freund
    Abstract:

    The process of freeze-thaw not only subjects bioproducts to potentially destabilizing stress, but also imposes challenges to retain container integrity. Shipment and storage of frozen products in glass vials and thawing of the vials prior to use at clinics is a common situation. Vial integrity failure during freeze-thaw results in product loss and safety issues. Formulations of biomolecules often include crystallizable excipients, which can cause glass vial breakage during freeze-thaw operations. In this study, mannitol formulations served as models for mechanistic investigation of root causes for vial breakage. Several parameters and their impacts on vial breakage were investigated, including mannitol concentration (5% and 15%), different freeze-thaw conditions (fast, slow, and staging), fill configurations (varying fill volume/vial size ratio), and vial tray materials (plastic, stainless steel, corrugated cardboard, aluminum, and polyurethane foam). The results in this study were subjected to a statistical proportion test. The data showed that large fill volumes strongly correlated with higher percentage of vial cracks. Furthermore, the 15% mannitol was found to cause more breakage than 5% mannitol, especially with fast temperature gradient. Significantly more thawing vial breakage occurred in the fast compared to slow freeze-thaw with all types of vial trays. The freezing breakage was substantially lower than the thawing breakage using the fast temperature gradient, and the trend was reversed with the slow temperature gradient. An intermediate hold at −30 °C prior to further decrease in temperature proved to be a practical approach to minimize mannitol-induced vial breakage. Thermal Mechanical Analysis (TMA) and strain gage techniques were employed to gain mechanistic insights, and it was found that the primary causes for mannitol-induced vial breakage were partial crystallization during freezing and “secondary” crystallization of non-crystallized fraction during thawing. The strain on the vial9s axial direction was significantly higher than the hoop direction, typically resulting in bottom lens of the vial coming off. Without a −30 °C hold, rapid volume expansions due to initial crystallization and secondary crystallization of mannitol were observed in TMA profiles, and these expansions were more apparent in 15% mannitol compared to 5% mannitol. With the introduction of a −30 °C hold step, abrupt expansions diminished in TMA profiles, suggesting that most of the mannitol crystallization occurred concurrently with ice solidification during the −30 °C holding step and, thus, secondary crystallization during thawing was minimal and the sudden expansion event was eliminated. Therefore, vial breakage during both freezing and thawing was reduced.

  • mechanistic studies of glass vial breakage for frozen formulations i vial breakage caused by crystallizable excipient mannitol
    Pda Journal of Pharmaceutical Science and Technology, 2007
    Co-Authors: Ge Jiang, Mike Akers, Manish Jain, Adrian Distler, Rob Swift, Manpreetvick S Wadhwa, Feroz Jameel, Sugu Patro, Jeremy Guo, Erwin Freund
    Abstract:

    The process of freeze-thaw not only subjects bioproducts to potentially destabilizing stress, but also imposes challenges to retain container integrity. Shipment and storage of frozen products in glass vials and thawing of the vials prior to use at clinics is a common situation. Vial integrity failure during freeze-thaw results in product loss and safety issues. Formulations of biomolecules often include crystallizable excipients, which can cause glass vial breakage during freeze-thaw operations. In this study, mannitol formulations served as models for mechanistic investigation of root causes for vial breakage. Several parameters and their impacts on vial breakage were investigated, including mannitol concentration (5% and 15%), different freeze-thaw conditions (fast, slow, and staging), fill configurations (varying fill volume/vial size ratio), and vial tray materials (plastic, stainless steel, corrugated cardboard, aluminum, and polyurethane foam). The results in this study were subjected to a statistical proportion test. The data showed that large fill volumes strongly correlated with higher percentage of vial cracks. Furthermore, the 15% mannitol was found to cause more breakage than 5% mannitol, especially with fast temperature gradient. Significantly more thawing vial breakage occurred in the fast compared to slow freeze-thaw with all types of vial trays. The freezing breakage was substantially lower than the thawing breakage using the fast temperature gradient, and the trend was reversed with the slow temperature gradient. An intermediate hold at -30 degrees C prior to further decrease in temperature proved to be a practical approach to minimize mannitol-induced vial breakage. Thermal Mechanical Analysis (TMA) and strain gage techniques were employed to gain mechanistic insights, and it was found that the primary causes for mannitol-induced vial breakage were partial crystallization during freezing and "secondary" crystallization of non-crystallized fraction during thawing. The strain on the vial's axial direction was significantly higher than the hoop direction, typically resulting in bottom lens of the vial coming off. Without a -30 degrees C hold, rapid volume expansions due to initial crystallization and secondary crystallization of mannitol were observed in TMA profiles, and these expansions were more apparent in 15% mannitol compared to 5% mannitol. With the introduction of a -30 degrees C hold step, abrupt expansions diminished in TMA profiles, suggesting that most of the mannitol crystallization occurred concurrently with ice solidification during the -30 degrees C holding step and, thus, secondary crystallization during thawing was minimal and the sudden expansion event was eliminated. Therefore, vial breakage during both freezing and thawing was reduced.

R K Weese - One of the best experts on this subject based on the ideXlab platform.

  • Physical Characterization of RX-55-AE-5 a Formulation of 97.5 % 2,6-Diamino-3,5-Dinitropyrazine-1-Oxide (LLM-105) and 2.5% Viton A Physical Characterization of RX-55-AE-5 A Formulation of 97.5 % 2,6-Diamino-3,5-Dinitropyrazine-1-Oxide (LLM-105) and 2.5% V
    2020
    Co-Authors: R K Weese, A K Burnham, H C Turner, T D Tran
    Abstract:

    ABSTRACT With the use of modern tools such as molecular modeling on increasingly powerful computers, new materials can be evaluated by their structural activity relationships, SAR, and their approximate physical and chemical properties can be calculated in some cases with surprising accuracy. These new capabilities enable streamlined synthetic routes based on safety, performance and processing requirements, to name a few [1]. Current work includes both understanding properties of old explosives and measuring properties of new ones. The necessity to know and understand the properties of energetic materials is driven by the need to improve performance and enhance stability to various stimuli, such as Thermal, friction and impact insult. This review will concentrate on the physical properties of RX-55-AE-5, which is formulated from heterocyclic explosive, 2,6-diamino-3,5-dinitropyrazine-1-oxide, LLM-105, and 2.5 % Viton A. Differential scanning calorimetry, DSC, was used to measure a specific heat capacity, for mass loss in an open pan. Thermal Mechanical Analysis, TMA, was used to measure the coefficient of Thermal expansion, CTE. The CTE for this formulation was calculated to be ≈ 61 µm/m•˚C. Impact, spark, friction and evolved gases are also reported

  • physical characterization of rx 55 ae 5 a formulation of 97 5 2 6 diamino 3 5 dinitropyrazine 1 oxide llm 105 and 2 5 viton a
    Presented at: North American Thermal Analysis Society 33rd Annual Conference Universal City CA United States Sep 19 - Sep 21 2005, 2005
    Co-Authors: R K Weese, A K Burnham, H C Turner, T D Tran
    Abstract:

    With the use of modern tools such as molecular modeling on increasingly powerful computers, new materials can be evaluated by their structural activity relationships, SAR, and their approximate physical and chemical properties can be calculated in some cases with surprising accuracy. These new capabilities enable streamlined synthetic routes based on safety, performance and processing requirements, to name a few [1]. Current work includes both understanding properties of old explosives and measuring properties of new ones. The necessity to know and understand the properties of energetic materials is driven by the need to improve performance and enhance stability to various stimuli, such as Thermal, friction and impact insult. This review will concentrate on the physical properties of RX-55-AE-5, which is formulated from heterocyclic explosive, 2,6-diamino-3,5-dinitropyrazine-1-oxide, LLM-105, and 2.5% Viton A. Differential scanning calorimetry, DSC, was used to measure a specific heat capacity, C{sub p}, of {approx} 0.950 J/g {center_dot} C, and a Thermal conductivity, {kappa}, of {approx} 0.160 W/m {center_dot} C. The Lawrence Livermore National Laboratory (LLNL) code Kinetics05 and the Advanced Kinetics and Technology Solutions (AKTS) code Thermokinetics were both used to calculate Arrhenius kinetics for decomposition of LLM-105. Both obtained an activation energy barrier E {approx} 180 kJ mol{supmore » -1} for mass loss in an open pan. Thermal Mechanical Analysis, TMA, was used to measure the coefficient of Thermal expansion, CTE. The CTE for this formulation was calculated to be {approx} 61 {micro}m/m {center_dot} C. Impact, spark, friction and evolved gases are also reported.« less

Ge Jiang - One of the best experts on this subject based on the ideXlab platform.

  • mechanistic studies of glass vial breakage for frozen formulations i vial breakage caused by crystallizable excipient mannitol
    Pda Journal of Pharmaceutical Science and Technology, 2007
    Co-Authors: Ge Jiang, Mike Akers, Manish Jain, Adrian Distler, Rob Swift, Manpreetvick S Wadhwa, Feroz Jameel, Sugu Patro, Erwin Freund
    Abstract:

    The process of freeze-thaw not only subjects bioproducts to potentially destabilizing stress, but also imposes challenges to retain container integrity. Shipment and storage of frozen products in glass vials and thawing of the vials prior to use at clinics is a common situation. Vial integrity failure during freeze-thaw results in product loss and safety issues. Formulations of biomolecules often include crystallizable excipients, which can cause glass vial breakage during freeze-thaw operations. In this study, mannitol formulations served as models for mechanistic investigation of root causes for vial breakage. Several parameters and their impacts on vial breakage were investigated, including mannitol concentration (5% and 15%), different freeze-thaw conditions (fast, slow, and staging), fill configurations (varying fill volume/vial size ratio), and vial tray materials (plastic, stainless steel, corrugated cardboard, aluminum, and polyurethane foam). The results in this study were subjected to a statistical proportion test. The data showed that large fill volumes strongly correlated with higher percentage of vial cracks. Furthermore, the 15% mannitol was found to cause more breakage than 5% mannitol, especially with fast temperature gradient. Significantly more thawing vial breakage occurred in the fast compared to slow freeze-thaw with all types of vial trays. The freezing breakage was substantially lower than the thawing breakage using the fast temperature gradient, and the trend was reversed with the slow temperature gradient. An intermediate hold at −30 °C prior to further decrease in temperature proved to be a practical approach to minimize mannitol-induced vial breakage. Thermal Mechanical Analysis (TMA) and strain gage techniques were employed to gain mechanistic insights, and it was found that the primary causes for mannitol-induced vial breakage were partial crystallization during freezing and “secondary” crystallization of non-crystallized fraction during thawing. The strain on the vial9s axial direction was significantly higher than the hoop direction, typically resulting in bottom lens of the vial coming off. Without a −30 °C hold, rapid volume expansions due to initial crystallization and secondary crystallization of mannitol were observed in TMA profiles, and these expansions were more apparent in 15% mannitol compared to 5% mannitol. With the introduction of a −30 °C hold step, abrupt expansions diminished in TMA profiles, suggesting that most of the mannitol crystallization occurred concurrently with ice solidification during the −30 °C holding step and, thus, secondary crystallization during thawing was minimal and the sudden expansion event was eliminated. Therefore, vial breakage during both freezing and thawing was reduced.

  • mechanistic studies of glass vial breakage for frozen formulations i vial breakage caused by crystallizable excipient mannitol
    Pda Journal of Pharmaceutical Science and Technology, 2007
    Co-Authors: Ge Jiang, Mike Akers, Manish Jain, Adrian Distler, Rob Swift, Manpreetvick S Wadhwa, Feroz Jameel, Sugu Patro, Jeremy Guo, Erwin Freund
    Abstract:

    The process of freeze-thaw not only subjects bioproducts to potentially destabilizing stress, but also imposes challenges to retain container integrity. Shipment and storage of frozen products in glass vials and thawing of the vials prior to use at clinics is a common situation. Vial integrity failure during freeze-thaw results in product loss and safety issues. Formulations of biomolecules often include crystallizable excipients, which can cause glass vial breakage during freeze-thaw operations. In this study, mannitol formulations served as models for mechanistic investigation of root causes for vial breakage. Several parameters and their impacts on vial breakage were investigated, including mannitol concentration (5% and 15%), different freeze-thaw conditions (fast, slow, and staging), fill configurations (varying fill volume/vial size ratio), and vial tray materials (plastic, stainless steel, corrugated cardboard, aluminum, and polyurethane foam). The results in this study were subjected to a statistical proportion test. The data showed that large fill volumes strongly correlated with higher percentage of vial cracks. Furthermore, the 15% mannitol was found to cause more breakage than 5% mannitol, especially with fast temperature gradient. Significantly more thawing vial breakage occurred in the fast compared to slow freeze-thaw with all types of vial trays. The freezing breakage was substantially lower than the thawing breakage using the fast temperature gradient, and the trend was reversed with the slow temperature gradient. An intermediate hold at -30 degrees C prior to further decrease in temperature proved to be a practical approach to minimize mannitol-induced vial breakage. Thermal Mechanical Analysis (TMA) and strain gage techniques were employed to gain mechanistic insights, and it was found that the primary causes for mannitol-induced vial breakage were partial crystallization during freezing and "secondary" crystallization of non-crystallized fraction during thawing. The strain on the vial's axial direction was significantly higher than the hoop direction, typically resulting in bottom lens of the vial coming off. Without a -30 degrees C hold, rapid volume expansions due to initial crystallization and secondary crystallization of mannitol were observed in TMA profiles, and these expansions were more apparent in 15% mannitol compared to 5% mannitol. With the introduction of a -30 degrees C hold step, abrupt expansions diminished in TMA profiles, suggesting that most of the mannitol crystallization occurred concurrently with ice solidification during the -30 degrees C holding step and, thus, secondary crystallization during thawing was minimal and the sudden expansion event was eliminated. Therefore, vial breakage during both freezing and thawing was reduced.

Weese R K - One of the best experts on this subject based on the ideXlab platform.

  • Exploring the Physical, Chemical and Thermal Characteristics of a New Potentially Insensitive High Explosive: RX-55-AE-5
    Lawrence Livermore National Laboratory, 2006
    Co-Authors: Weese R K, Burnham A K, Turner H C, Tran T D
    Abstract:

    Current work at the Energetic Materials Center, EMC, at Lawrence Livermore National Laboratory (LLNL) includes both understanding properties of old explosives and measuring properties of new ones [1]. The necessity to know and understand the properties of energetic materials is driven by the need to improve performance and enhance stability to various stimuli, such as Thermal, friction and impact insult. This review will concentrate on the physical properties of RX-55-AE-5, which is formulated from heterocyclic explosive, 2,6-diamino-3,5-dinitropyrazine-1-oxide, LLM-105, and 2.5% Viton A. Differential scanning calorimetry (DSC) was used to measure a specific heat capacity, C{sub p}, of {approx} 0.950 J/g{center_dot} C and a Thermal conductivity, {kappa}, of {approx} 0.475 W/m{center_dot} C. The LLNL kinetics modeling code Kinetics05 and the Advanced Kinetics and Technology Solutions (AKTS) code Thermokinetics were both used to calculate Arrhenius kinetics for decomposition of LLM-105. Both obtained an activation energy barrier E {approx} 180 kJ mol{sup -1} for mass loss in an open pan. Thermal Mechanical Analysis, TMA, was used to measure the coefficient of Thermal expansion (CTE). The CTE for this formulation was calculated to be {approx} 61 {micro}m/m{center_dot} C. Impact, spark, friction are also reported

  • Physical Characterization of RX-55-AE-5 a Formulation of 97.5 % 2,6-Diamino-3,5-Dinitropyrazine-1-Oxide (LLM-105) and 2.5% Viton A
    Lawrence Livermore National Laboratory, 2005
    Co-Authors: Weese R K, Burnham A K, Turner H C, Tran T D
    Abstract:

    With the use of modern tools such as molecular modeling on increasingly powerful computers, new materials can be evaluated by their structural activity relationships, SAR, and their approximate physical and chemical properties can be calculated in some cases with surprising accuracy. These new capabilities enable streamlined synthetic routes based on safety, performance and processing requirements, to name a few [1]. Current work includes both understanding properties of old explosives and measuring properties of new ones. The necessity to know and understand the properties of energetic materials is driven by the need to improve performance and enhance stability to various stimuli, such as Thermal, friction and impact insult. This review will concentrate on the physical properties of RX-55-AE-5, which is formulated from heterocyclic explosive, 2,6-diamino-3,5-dinitropyrazine-1-oxide, LLM-105, and 2.5% Viton A. Differential scanning calorimetry, DSC, was used to measure a specific heat capacity, C{sub p}, of {approx} 0.950 J/g {center_dot} C, and a Thermal conductivity, {kappa}, of {approx} 0.160 W/m {center_dot} C. The Lawrence Livermore National Laboratory (LLNL) code Kinetics05 and the Advanced Kinetics and Technology Solutions (AKTS) code Thermokinetics were both used to calculate Arrhenius kinetics for decomposition of LLM-105. Both obtained an activation energy barrier E {approx} 180 kJ mol{sup -1} for mass loss in an open pan. Thermal Mechanical Analysis, TMA, was used to measure the coefficient of Thermal expansion, CTE. The CTE for this formulation was calculated to be {approx} 61 {micro}m/m {center_dot} C. Impact, spark, friction and evolved gases are also reported

  • Physical Characterization of RX-55-AE-5 A formulation of 97.5 % 2, 6-diamino-3, 5-dinitropyrazine-1-oxide (LLM 105) and 2.5 % Viton A
    Lawrence Livermore National Laboratory, 2005
    Co-Authors: Weese R K, Burnham A K, Turner H C, Tran T
    Abstract:

    With the use of modern tools such as molecular modeling on increasingly powerful computers, new materials can be evaluated by their structural activity relationships, SAR, and their approximate physical and chemical properties can be calculated in some cases with surprising accuracy. These new capabilities enable streamlined synthetic routes based on safety, performance and processing requirements, to name a few [1]. Current work includes both understanding properties of old explosives and measuring properties of new ones. The necessity to know and understand the properties of energetic materials is driven by the need to improve performance and enhance stability to various stimuli, such as Thermal, friction and impact insult. This review will concentrate on the physical properties of RX-55-AE-5, which is formulated from heterocyclic explosive, 2,6-diamino-3,5-dinitropyrazine-1-oxide, LLM-105, and 2.5% Viton A. Differential scanning calorimetry, DSC, was used to measure a specific heat capacity, C{sub p}, of {approx} 0.950 J/g{center_dot} C, and a Thermal conductivity, {kappa}, of {approx} 0.160 W/m{center_dot} C. The Lawrence Livermore National Laboratory (LLNL) code ''Kinetics05'' and the Advanced Kinetics and Technology Solutions (AKTS) code ''Thermokinetics'' were both used to calculate Arrhenius kinetics for decomposition of LLM-105. Both obtained an activation energy barrier E {approx} 180 kJ mol{sup -1} for mass loss in an open pan. Thermal Mechanical Analysis, TMA, was used to measure the coefficient of Thermal expansion, CTE. The CTE for this formulation was calculated to be {approx} 61 {micro}m/m{center_dot} C. Impact, spark, friction and evolved gases are also reported