Initial Decomposition Process Research Articles

Effect of sulfuric residual acid on the physicochemical properties, thermal behavior, and decomposition kinetics of nitrocellulose

The acid remaining in the nitrocellulose (NC) during the production process have some influence on its structure and stability. Herein, physicochemical properties, thermal behavior, and decomposition kinetics of NC before and after sulfuric acid treatment were thoroughly investigated using a series of analytical instruments in this paper. It is found that the nitrogen content and relative molecular weight of NC-0.968% that undergoing impregnation with sulfuric acid and drying is decreased by 0.58% and 16% (decreasing rate), respectively, suggesting that the presence of excess sulfuric acid leads to denitrification of NC at room temperature as well as breakage of the glucoside bond, with a greater effect on the latter. Moreover, the results of X-ray diffraction (XRD), scanning electron microscopy (SEM), and dynamic vapor sorption (DVS) indicate that the presence of sulfuric acid did not cause significant changes in the crystalline structure of NC, but severely damage the microscopic morphology, resulting in a large number of micropores appearing on its fiber surface, which enhances the hygroscopicity of NC. In addition, the combined Model-based kinetic results indicate that the decomposition reaction process of NC- 0.968% has a step one more than that of pure NC, which is attributed to the acid-catalyzed denitrification of NC and the breaking of glucoside bonds. Combined with the experimental results of TG-DSC-FITR, it shows that the presence of acid mainly affects the initial decomposition process of NC, while the fracture of the glucose ring frame and oxygen bridge in the NC molecular structure is more dependent on the action of NO2 and the decomposition temperature.

Insect Colonisation and the Decomposition Process in Aerated versus Watertight Burial Systems.

In recent years, burial systems have covered increasingly higher costs due to the pollution caused by decomposition products. These products are understood as chemicals and microorganisms in the surrounding soil and groundwater and represent a topical issue. The purpose of this research was to ascertain the extent of decomposition when pig carcasses are buried in two different burial systems ("aerated" vs. "watertight") and catalogue the arthropods associated with burials at different time-points of removal from niches (after 6, 12, 24, 36, and 60 months). Thirteen taxa were collected in aerated niches, whereas five were collected in watertight niches. The initial access or exclusion of insect colonisers affected overall functional activity. Two Diptera species, Hydrotaea capensis and Megaselia scalaris, were the most abundant, supporting the hypothesis that insects can colonise carcasses in aerated burial systems. Furthermore, some species of bacteria have been documented as facilitators of the initial decomposition process of the carcass. Most bacterial colonies develop only in aerated niches. The trial showed that the first enzymatic-bacterial and insect actions helped promote the process of cadaveric decomposition and later skeletonisation, mainly when associated with aeration modes of the tomb/mound. The results obtained provide essential information on the process of human decomposition and taphonomy in cemeteries. Moreover, these data could benefit forensic science by adding information on insect colonisation and body modification in medico-legal investigations concerning the post-mortem interval in exhumed bodies and illegal burials.

A detailed chemical kinetic mechanism of 1,1-diamino-2,2-dinitroethylene (FOX-7) initial decomposition in the gas phase

1,1-Diamino-2,2-dinitroethylene (FOX-7 or DADNE) is a promising ingredient of the low-vulnerability propellants. However, one of the major concerns in its further development and applications is the lack of detailed kinetic mechanism for its initial decomposition in the gas phase. In this study, a detailed chemical kinetic mechanism consisting of 38 species and 131 reactions was developed to describe the initial decomposition process of FOX-7. At first, a comprehensive reaction network was established with the aid of reactive molecular dynamics (MD) simulation. Then, the potential energy surfaces (PES) for both unimolecular and bimolecular reactions were identified at the QCISD(T)/CBS//M062X/6-311++G(d,p) level of theory. The rate coefficients were obtained by solving RRKM/ME, and the thermochemical properties of relevant species were calculated at CBS-APNO/G3/G4 levels with the atomization method. Finally, these kinetic and thermochemistry data were processed into a kinetic mechanism and used to simulate the initial decomposition process of FOX-7. The results demonstrated that the H-atom transfer to the beta carbon atom (enamino-imino isomerization) followed by the nitro group elimination dominates the initial decomposition, and the reaction FOX-7 = R3a + NO2 becomes the most significant one under high temperatures (Channel C3). Besides, bimolecular reactions also play a role as the decomposition goes on. Overall, this work provides quantitative predictions of the reaction pathways of gas-phase FOX-7 initial decomposition, and it would serve as a solid foundation for the development of a fully detailed combustion kinetic mechanism for FOX-7.

Fast pyrolysis of pulverized coal at high temperatures and fuel nitrogen migration characteristics in a wire mesh reactor

ABSTRACT Pulverized coal (PC) pyrolysis is an indispensable process for coal thermal conversion and utilization. The transformation of fuel-N into fast pyrolysis is a basis for the investigation of nitrogen migration in coal combustion. In this paper, a wire mesh reactor was used to study the initial decomposition processes and to reveal the final pyrolysis yield and composition distribution during the fast pyrolysis process. Furthermore, the initial pyrolysis characteristics of PC with different ash contents were presented and compared. The results showed that both Huangling coal (with higher volatile) and Wuhai coal (with higher ash content) showed a similar trend, and the pyrolysis ratio increased with the increased pyrolysis final temperature. The pyrolysis ratio at the high heating rate was estimated to exceed that at the low heating rate by 2%–10%. With the temperature increased, the char-N yield decreased first and then tended to be stable, and most of nitrogen remained in the char (more than 55%). An increase in heating rate made the pyrolysis zone to shift toward higher temperature, and it enhanced the yields of volatile and tar as well as the proportion of tar in volatile. Besides, the heating rate increased from 10°C·s−1 to 1500°C·s−1, the yield of tar-N increased from 4% to 14% and gas-N decreased from 28% to 19%. Overall, NH3 yielded was higher than HCN, which became more apparent at high heating rates. The content of the N-6 was positively related to the coal pyrolysis ratio.

Thermal behavior and decomposition kinetics of nitro‐1,2,4‐triazol‐3‐one by gas manometric technique

AbstractIsothermal decomposition kinetics play an important role in the stability assessment, risk assessment, and reaction mechanism inference of energetic materials. Herein, the thermal decomposition of nitro‐1,2,4‐triazol‐3‐one (NTO) was investigated using a self‐development isothermal decomposition gas manometric device at both high and low temperature ranges. The kinetic parameters were calculated by model‐free method and model‐fitting method. The results show that the activation energies determined by these two methods are in good agreement. At 473–493 K, the entire decomposition process of NTO showed two distinct stages. The activation energy (Ea) and pre‐exponential factor (lnA) in the first stage are 260.1 ± 11.5 kJ mol−1 and 52.5 ± 2.9 s−1, respectively, while they are 166.0 ± 24.5 kJ mol−1 and 28.4 ± 6.1 s−1 in the second stage. At 383–423 K, the initial decomposition process of NTO was investigated. During this process, Ea is 99.8 ± 3.2 kJ mol−1 and lnA is 11.5 ± 1.0 s−1. According to the kinetic results, a mechanism was speculated to be the transition of a rate‐limiting step from nucleation and nuclei growth to the gas diffusion. Moreover, the Ea–lnA sets were found to lie on the kinetic compensation regression line, which indicates that the kinetic data in this work are reliable. All the results will further support and complement the kinetic database of NTO.

Reactive molecular dynamics studies of the interfacial reactions of core-shell structured CL-20-based aluminized explosives at high temperature

The thermal decomposition processes of CL-20 nanoparticle (NP), core-shell structured CL-20@Al NP, and CL-20@AlO NP were studied through reactive molecular dynamics simulations. The results are as follows: (1) the CL-20@Al and CL-20@AlO NPs decomposed earlier than the CL-20 NP; (2) the Al shell experienced the melting-aggregation process and gradually changed from a shell structure to block aluminized clusters; (3) different in the decomposition of the CL-20 NP, N2 appeared first in the decomposition of the CL-20@Al and CL-20@AlO NPs, indicating that Al changed the initial decomposition process of CL-20; (4) the quantities of NO2, NO, and CO2 produced during the decompositions of the CL-20@Al and CL-20@AlO NPs were much lower than those produced during the decomposition of CL-20 NP. This occurred because the Al atoms had high activity at high temperature and attacked these products to produce massive aluminized substances; (5) Al significantly promoted the movement of H and N atoms but impeded that of O and C atoms in the three systems. This study will present fundamental information about the interfacial behaviors of aluminized explosives.

Molecular insights into the role of O2 in reversed C2H6/C2H4 separation on metal–organic frameworks

Previous experimental studies have shown that C2H4-selective metal–organic frameworks (MOFs) can be reversed to C2H6-selective MOFs by introducing an oxygen molecule (O2) into the MOF. The O2 functionalization strategy provides a new insight into one-step C2H4 purification; however, the molecular-level understanding of the reversed separation mechanism remains theoretically and experimentally unclear, which limits further material refinement. In this study, we explored the influence of O2 on the C2H6/C2H4 selectivity of a Cr-BTC MOF via density functional theory (DFT) calculations and grand canonical Monte Carlo simulations within the newly DFT-derived force fields. Results suggest that O2 was antiferromagnetically coupled to the open Cr site, with an end-on pattern forming the superoxo site. The presence of superoxide adducts decreased the dipole moment of the open-metal site by 5.95 debye. Furthermore, the altered gas selectivity could be attributed to the superoxo site blocking the donation and back-donation interactions between Cr and C2H4. This removes the highly polarized C2H4-selective site, while enhancing the pore channel environmental inertness for preferential C2H6 adsorption. To assess the performance of the reversed separation strategy under humid air conditions, ab initio molecular dynamics with metadynamics were used to determine the water stabilities of Cr-BTC and oxidized conjugates. We revealed that O2 introduction weakened the metal-linker bond and reduced the free-energy barrier for the initial framework decomposition process, which may hinder the application of gas separation in further practical environments. These findings provide theoretical support for oxidized MOFs with reversed separation performance and facilitate intentional post-synthetic MOF modifications for paraffin-selective adsorbent design, a critical need for energy applications and the petroleum industry.

Climate, Soil, and Plant Controls on Early-Stage Litter Decomposition in Moso Bamboo Stands at a Regional Scale

Moso bamboo (Phyllostachys edulis) is currently distributed across a wide geographical area in East Asia. As a common bamboo species occurring along a broad environmental gradient, there is a need to understand how environmental and biotic drivers affect belowground processes at large scales. In this study, we investigated the influence of climate, soil properties, stand characteristics, and organic matter input parameters as potential drivers of the initial decomposition process in Moso bamboo stands at a regional scale. Using the Tea Bag Index method, we estimated the initial decomposition rate (k) and stabilization factor (S; potential long-term carbon storage) from standard litter incubated at 13 sites across southern Japan and Taiwan. We found that both decomposition parameters were strongly affected by the climate. The climatic conditions during the incubation period better explained the variance in k. In contrast, the long-term climate was more important for S. Notably, temperature and precipitation interactively affected the initial decomposition rates. This interaction showed that in warmer sites, precipitation increased k, whereas in cooler sites, precipitation had no effect or even decreased k. Soil parameters had no influence on k and only had minor effects on S. A structural equation model showed that the stabilization factor was indirectly affected by stand density, which suggests that higher bamboo densities could increase litter stabilization by increasing above-and below-ground organic matter input. Our study highlights the central role of climate in controlling decomposition processes in Moso bamboo stands on a broad scale. Moreover, differences in stand structure can indirectly affect potential soil carbon storage through changes in organic matter input and soil conditions.

Decomposition of Al13 promoted by salicylic acid under acidic condition: Mechanism study by differential mass spectrometry method and DFT calculation

Decomposition of the polycation Al13O4(OH)24(H2O)127+ (Al13) promoted by ligand is a vital subject to advance our understanding of natural and artificial occurrence and evolution of aluminum ions, especially in the case of acidic condition that dissolved Al3+ species can be released from the Al-bearing substances. However, the microscopic pathway of synchronous proton-promoted and ligand-promoted decomposition process for Al13 is still in the status of ambiguity. Herein, we applied differential mass spectrometry method and DFT calculation to study the initial detailed process of Al13 decomposition under the presence of proton and salicylic acid (H2Sal). Mass results showed that the mononuclear Al3+-H2Sal complexes dominated the resulting Al species, whereas the monodentate complex Al13HSal6+ was not observed in the spectra. The difference of decomposition levels between the ligand/Al ratio 0.2 and 0.5 cases revealed that proton and ligand performed synergistic effect in initial Al13 decomposition process, and the proton transfer determined the ring closure efficiency. The ring closure reaction is the prerequisite for the collapse of Al13 structure and detachment of the mononuclear complex. DFT calculations reveal that hydrogen bond plays an important role in inducing the formation of chelated complex accompanying proton transfer. Attachment of protons at the bridging OH− can elongate and weaken the critical bond between targeted Al3+ and µ4-O2- resulting from delocalization of electron pairs in the oxygen atom. These results demonstrate the detailed mechanism of Al13 composition promoted by ligand and proton, and provide significant understanding for further application and control of Al13.

Initial decomposition step and bimolecular hydrogen transfer of 3, 3′-diamino-4, 4′-azoxyfurazan under high pressure and high temperature

3, 3′-diamino-4, 4′-azoxyfurazan (DAAF) is a promising energetic furazan compound. Few works about its chemical and physical properties under high pressure and high temperature are reported so far. Here the thermal decompositions of DAAF under high temperature and/or high pressure with neon gas or liquid water were studied using Raman spectra. Under high temperature and ambient pressure, the decomposition sequence of DAAF begins with the unimolecular homolysis of CNazoxy and further followed by the cleavage of NH in NH2 group and the rupture of furazan ring. Application of high pressure induces the different initial decomposition process accompanied the variation of the intermolecular and intramolecular interactions. The initial step of DAAF is the breakdown of NH at 473 K and 0.9 GPa, which facilitates the bimolecular hydrogen transfer from NH2 group to Oazoxy-N and finally induces the dissociation of the O from azoxy group. It results in the formation of DAAzF at 483 K when using neon as pressure transmitting medium. Moreover, big and fine rod-like DAAzF crystals are formed above 493 K at 0.8 GPa employing water as pressure transmitting medium. The existence of super high temperature water leads to the bimolecular hydrogen transfer and dissociation of Oazoxy from DAAF more easily for the interaction of Oazoxy…H and more DAAF crystals transformation into DAAzF.

DFT Calculations for the HONO Elimination Process of CL-20 Conformers

The HONO elimination process is regarded to be an important initial decomposition process of energetic nitramines. Four CL-20 conformers based on the ε-CL-20 were obtained by the optimization at the m062x/cc-pvtz level in this study, and the Transition State (TS) and Intrinsic Reaction Coordinate (IRC) calculations were carried out at the same level. In addition, the rate coefficients and activation energy of the HONO elimination process were evaluated using conventional transition state theory (TST) and canonical variational transition state theory (CVT) with Eckart and small-curvature tunneling (SCT) methods to correct the transmission coefficients for the quantum tunneling effect. The calculation results have shown that the HONO elimination process concerning the nitro groups located on six numbered rings is the hardest to happen, and it seems that the longer distance between nitro groups and the adjacent hydrogen atom would result in the higher barrier energy; the HONO elimination process is most likely to happen for the axial positioning of nitro groups located on five numbered rings and most unlikely to happen for the ones located on six numbered rings; CL-20 II and CL-20 IV conformers are the most unstable one and most stable one concerning the reaction difficulty of the HONO elimination process.

Insights into the thermal degradation mechanisms of polyethylene terephthalate dimer using DFT method

The thermal degradation mechanisms of polyethylene terephthalate (PET) dimer were studied by the B3P86 density functional theory (DFT) approach at 6–31++G (d, p) base set in this paper. Seven possible reaction paths were designed and analyzed, and the thermodynamic parameters for all reactions were computed. The calculated results indicate that the bond dissociation energy values (BDEs) of C–C bonds on the main-chain are the smallest, followed by those of C–O bonds. The kinetics analysis indicates that the concerted reactions are obviously liable to occur rather than radical reactions in the initial thermal decomposition process. In the processes of initial reactions, all concerted reactions occurred by six-membered cyclic transition states (TSs) are more prone to carry out than those happened by four-membered cyclic transition states. The research results show that the primary products of PET dimer pyrolysis are terephthalic acid, vinyl terephthalate, CH3CHO and divinyl terephthalate. CH3CHO is mainly formed by a concerted reaction in the initial degradation process, and CO2 is mainly produced by the decarboxylation via a concerted reaction and CO is mainly produced by the decarbonylation of a radical in secondary degradation.

Thermal stability of quasicrystals in an icosahedral-phase-strengthened aluminum alloy

The thermal stability and decomposition products of the quasicrystalline I-phase in a powder-processed Al-2.8Cr-1.51Mn-0.28Co-0.31Zr alloy (in at. %) have been studied using thermal analysis, electron microscopy studies on heat-treated samples, and in situ TEM heating studies. The alloy was consolidated through blind-die compaction and exhibited a nano-composite FCC Al matrix with ≈25% by volume of I-phase dispersoids. In samples heat treated ex situ at 300–450 °C, two transformations were observed. Initially, the I-phase decomposed by transforming to a ternary Al45(Cr,Mn)7 phase. This decomposition was accompanied by ejection of Co, which formed Al9Co2. After longer exposures, the Al45(Cr,Mn)7 transformed to an Al12(Cr,Mn) phase with a coarse irregular morphology. In situ TEM observations on sections through powder particles were used to identify the onset times for the initial decomposition process, and these were used together with activation energies determined by Kissinger analysis of isothermal DSC data to construct transformation curves. TEM measurements of the Co content from dispersoids in the samples heat treated ex situ were used to determine the extent of I-phase decomposition, and these data matched well with the trends expected from the curves. These observations provide a useful insight into the processing and operating conditions that might be used for such QC-reinforced Al alloys.

Revealing the etching process of water-soluble Au25 nanoclusters at the molecular level

Etching (often considered as decomposition) is one of the key considerations in the synthesis, storage, and application of metal nanoparticles. However, the underlying chemistry of their etching process still remains elusive. Here, we use real-time electrospray ionization mass spectrometry to study the reaction dynamics and size/structure evolution of all the stable intermediates during the etching of water-soluble thiolate-protected gold nanoclusters (Au NCs), which reveal an unusual “recombination” process in the oxidative reaction environment after the initial decomposition process. Interestingly, the sizes of NC species grow larger and their ligand-to-metal ratios become higher during this recombination process, which are distinctly different from that observed in the reductive growth of Au NCs (e.g., lower ligand-to-metal ratios with increasing sizes). The etching chemistry revealed in this study provides molecular-level understandings on how metal nanoparticles transform under the oxidative reaction environment, providing efficient synthetic strategies for new NC species through the etching reactions.

The influence of different sample preparation on mechanical properties of human iliotibial tract

In the run-up to biomechanical testing, fresh human tissue samples are often frozen in order to inhibit initial decomposition processes and to achieve a temporal independence of tissue acquisition from biomechanical testing. The aim of this study was to compare the mechanical properties of fresh tissue samples of the human iliotibial tract (IT) to fresh-frozen samples taken from the same IT and those modified with different concentrations of Dimethylsulfoxide (DMSO) prior to freezing. All samples were partial plastinated and destructive tensile tests were conducted with a uniaxial tensile test setup. A plastination technique already established in the laboratory was modified to improve the clamping behaviour of the samples. Material failure was caused by a gradual rupture of the load-bearing collagen fibre bundles. Contrary to our expectations, no significant difference was found between the tensile strength of fresh and fresh frozen specimens. The addition of 1 wt% DMSO did not increase the tensile strength compared to fresh-frozen samples; an addition of 10 wt% DMSO even resulted in a decrease. Based on our findings, the use of simple fresh-frozen specimens to determine the tensile strength is viable; however fresh specimens should be used to generate a complete property profile.

Thermal decomposition of vegetable insulating oils from reactive molecular dynamics

Thermal decomposition reaction mechanisms and product distributions of vegetable oils were studied using reactive force field (ReaxFF) molecular dynamics (MD) simulations. The initial decomposition process, initiated by ester bond cleavages, followed by decarboxylation reactions and CC bond cleavages, was suggested by monitoring reaction trajectories and supported via QM calculations. The main decomposition products predicted by ReaxFF method were CH4, C2H2, C2H4, C2H6, C3H6, CO2, CO, H2, H2O, showing a good agreement with experimental results. In addition, the temperature impacts on product distributions were also carried out to determine characteristic products under different conditions. Accordingly, we noted that the most abundant product switched from (CO2 and C2H4) to H2 along with the temperature increasing, which supplied new insights for the thermal decomposition of vegetable insulating oils.

Thermal hazard analysis and initial decomposition mechanism of 5-(4-pyridyl)tetrazolate-methylene tetrazole

5-(4-Pyridyl)tetrazolate-methylene tetrazole (H4-PTZ-methylene tetrazole) was prepared. Thermokinetic characteristics of H4-PTZ-methylene tetrazole were described through differential scanning calorimetry (DSC). Ozawa method, Kissinger method, and isoconversional approach were used to calculate the kinetic parameters. Thermal safety parameters, such as self-accelerated decomposition temperature (SADT) and thermal ignition temperature (TTIT), were evaluated from experimental results. The initial decomposition process was investigated using experimental and theoretical calculations. Geometric optimisation, Mulliken charges, electrostatic potentials, and decomposition pathways were explored using Gaussian 16. The simultaneous dissociation of C7–N8 and N9–N10 bonds (DM1) and of C13–N17 and N15–N16 bonds (DM2) had lower energy barriers. The theoretical apparent activation energy was higher than the experimental one. As a novel finding, the exothermic process observed through DSC was primarily because of the reaction that opened the tetrazole ring, which released nitrogen.

Glyoxal improved functionalization of starch with AZC enhances the hydrophobicity, strength and UV blocking capacities of co-crosslinked polymer

An effective and facile approach to functionalize starch was developed using glyoxal and ammonium zirconium carbonate (AZC) as the co-crosslinking agents. The resultant starch was characterized for chemical structure, surface morphology, thermal stability, optical and hydrophobic properties and mechanical strength. 1H and 13C nuclear magnetic resonance (NMR) spectrum confirmed the successful Schiff-base reaction on the starch. X-ray diffraction (XRD) showed that the low glyoxal dosage had an adverse impact on the degree of crystallinity. Thermalgravimetric (TG) results revealed the weakened thermal stability at the initial decomposition process and enhanced thermal stability above the maximum degradation temperature. A smoother surface on the resultant film was observed by scanning electron microscopy (SEM) after the addition of glyoxal. Significantly, enhanced mechanical and hydrophobic properties as well as ultraviolet (UV) blocking capacity of the resultant starch film were achieved at 5% (wt) glyoxal and 5% (wt) AZC content. Improved hydrophobic property and mechanical strength were also obtained even with very low dosages of glyoxal (0.5%, wt) and AZC (2.5%, wt). This new type of starch with double functionalities (i.e., hydrophobic and UV blocking capacity) provides beneficial implications for improving the performance of starch-based materials.

Ab initio calculations of the NO2 fission for CL-20 conformers

ABSTRACTNO2 fission is regarded to be the most important initial decomposition process of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20). In this study, four CL-20 conformers based on the ε-CL-20 were obtained after the optimization at m062x/cc-pvtz level, and the bond length, bond order and bond dissociation energy of the N-N bonds were examined to investigate the stability of these bonds. In addition, the rate constants and activation energy of the NO2 fission were evaluated using the microcanonical variational transition state theory (μVT). The calculation results have shown that N-N bonds in the case of pseudo-equatorial and axial of nitro groups are the most stable and the least stable, respectively, by evaluating the bond length, bond order and minimum energy path (MEP). The NO2 fission rate constants are affected by not only the stability of N-N bonds but also the repulsion forces from the other nitro groups, and the fission process for pseudo-equatorial positioning of nitro groups is easier to be accelerated due to the increase of the repulsion forces. The decomposition of CL-20 conformer may mainly originate from the fission of the pseudo-equatorial positioning of nitro groups, especially for CL-20 III conformer because of the significant low activation energy.

Thermal stability and safety of dimethoxymethane oxidation at low temperature

In this work, thermal oxidation reaction of dimethoxymethane (DMM) at low temperature was investigated with a custom-designed mini closed pressure vessel test (MCPVT) employed. The initial auto-oxidation, thermal decomposition and deep radical oxidation processes were revealed by analyzing the behavior of oxidation temperature (T) and pressure (P) in the process of MCPVT monitoring. Peroxides generated from DMM auto-oxidation were measured by iodimetry and thin-layer chromatography (TLC). The dominant peroxide was separated from oxidation products via column chromatography, with structure characterized by mass spectrometry (MS), 1H and 13C nuclear magnetic resonance (NMR). The thermal decomposition characteristics were determined by differential scanning calorimeter (DSC). Results show that the oxidation was mainly initiated by hydrogen abstraction on the methylenedioxy (O-CH2-O) of DMM when temperature was above about 310 K. The primary product of hydroperoxide, hydroperoxy(methoxymethoxy)methane was found in DMM oxidation for the first time, with a high level. Its exothermic onset temperature (T0) and decomposition heat (QDSC) are 372.87 K and 2431.37 J·g−1, respectively. The thermal decomposition could lead to thermal runaway of oxidation, and further transform into an explosion. In most cases, the release of radical pool after peroxides decomposition would induce a rapidly radical oxidation of DMM through an endothermic reaction at about 410 K.