Pure Nitrocellulose Research Articles

Effect and mechanism of reductive polyaniline on the stability of nitrocellulose

The search for new green and efficient stabilizers is of great importance for the stabilization of nitrocellulose (NC). This is due to the shortcomings of traditional stabilizers, such as high toxicity. In this study, reduced polyaniline (r-PANI), which has a similar functional structure to diphenylamine (DPA) but is non-toxic, was prepared from PANI based on the action with N2H4 and NH3–H2O, and used for the first time as a potential stabilizer for NC. XPS, FTIR, Raman, and SEM were used to characterize the reduced chemical structure and surface morphology of r-PANI. In addition, the effect of r-PANI on the stabilization of NC was characterized using DSC, VST, isothermal TG, and MMC. Thermal weight loss was reduced by 83% and 68% and gas pressure release by 75% and 49% compared to pure NC and NC&3%DPA, respectively. FTIR and XPS were used to characterize the structural changes of r-PANI before and after reaction with NO2. The 1535 cm−1 and 1341 cm−1 of the FTIR and the 404.98 eV and 406.05 eV of the XPS showed that the –NO2 was generated by the absorption of NO2. Furthermore, the quantum chemical calculation showed that NO2 was directly immobilized on r-PANI by forming –NO2 in the neighboring position of the benzene ring.

Synergistic effect of nitrocellulose coating on structural and reactivity stabilization of ammonium nitrate oxidizer

The present work aims to stabilize the room temperature allotropic transition of ammonium nitrate (AN) particles utilizing a microencapsulation technique, which involves solvent/non-solvent in which nitrocellulose (NC) has been employed as a coating agent. The SEM micrographs revealed distinct features of both pure AN and NC, contrasting with the irregular granular surface topography of the coated AN particles, demonstrating the adherence of NC on the AN surface. Structural analysis via infrared spectroscopy (IR) demonstrated a successful association of AN and NC, with slight shifts observed in IR bands indicating interfacial interactions. Powder X-ray Diffraction (PXRD) analysis further elucidated the structural changes induced by the coating process, revealing that the NC coating altered the crystallization pattern of its pure form. Thermal analysis demonstrates distinct profiles for pure and coated AN, for which the coated sample exhibits a temperature increase and an enthalpy decrease of the room temperature allotropic transition by 6 °C, and 36%, respectively. Furthermore, the presence of NC coating alters the intermolecular forces within the composite system, leading to a reduction in melting enthalpy of coated AN by ∼39% compared to pure AN. The thermal decomposition analysis shows a two-step thermolysis process for coated AN, with a significant increase in the released heat by about 78% accompanied by an increase in the activation barrier of NC and AN thermolysis, demonstrating a stabilized reactivity of the AN-NC particles. These findings highlight the synergistic effect of NC coating on AN particles, which contributed to a structural and reactive stabilization of both AN and NC, proving the potential application of NC-coated AN as a strategically advantageous oxidizer in composite solid propellant formulations.

Effect of faujasite zeolites on the thermal stability and degradation kinetics of nitrocellulose

ABSTRACT In the present work, to enhance the thermal stability of nitrocellulose (NC), the effect of inorganic stabilizers, namely, Y-ammonium or Y-hydrogen zeolites, has been investigated. Comparative tests were conducted to assess the physicochemical properties and thermal behavior of the nitrocellulose supplemented with these substances. Various analytical techniques were employed. The obtained results highlighted the exceptional scavenging performance of these inorganic stabilizers. Notably, the NC/Y-ammonium and NC/Y-hydrogen samples exhibited higher retention of NO x , compared to NC/diphenylamine (DPA). The FTIR spectra of the NC/stabilizer systems revealed that the morphology and chemical structure of the conventional NC remained unaltered with the incorporation of 3 wt.% of stabilizer. Moreover, the B&J and VST tests indicated that the stability of the NC/stabilizer blends, specifically those incorporating NC/Y-ammonium and NC/Y-hydrogen zeolites, surpassed that of both pure NC and NC/DPA samples. It is also revealed that Y-ammonium and Y-hydrogen zeolites have a minimal impact on the decomposition temperature of NC (Ea = 137 kJ.mol−1, log (A) > 12.7 s−1), but exhibit a significant increase in the apparent activation energy and pre-exponential factor (Δ Ea > 33–43 kJ.mol−1, Δ log (A) > 2.3–4.9 s−1). These findings highlight promising aspects of utilizing inorganic stabilizers to substitute DPA in the industrial production of energetic materials.

Preparation, formation mechanism, and performance of nitrocellulose aqueous coating based on the anti-solvent method

The organic solvent-based nitrocellulose (NC) coatings exhibit a high volatile solvent content, leading to significant environmental pollution. Whereas, existing waterborne NC-based coating have demonstrated poor water resistance and complex application methods. Therefore, this study aims to develop a green and highly water-resistant waterborne NC-based coating system utilizing a simple anti-solvent method with two environmentally friendly plasticizers, namely acetyl tributyl citrate (ATBC) and triethyl citrate (TEC), as film-forming additives. The dynamic light scattering (DLS) studies revealed that the particle size of NC-based nanoparticles increased with an increase in ATBC content, while it remained relatively constant with an increase in TEC content. Moreover, the particle size results demonstrated that the storage stability of aqueous dispersions containing NC/ATBC (NA) was superior to those containing NC/TEC (NT). Additionally, the physicochemical properties of aqueous dispersions-based films (Ndis), including film formation, hygroscopicity, water resistance, transparency, thermal stability, and mechanical properties were evaluated using solvent-based films (Nsol) as control samples. The results demonstrated that the Ndis films exhibited a dense and uniform structure, with physical and chemical properties that were essentially comparable to those of Nsol films. However, the mechanical properties of Ndis films were somewhat influenced by the nanoparticle size, leading to reduced mechanical performance when the particle size of nanoparticles in the aqueous dispersion was excessively large. The equilibrium moisture content for NA and NT films were reduced to 1.119% and 1.872%, respectively, at a relative humidity of 95%, in comparison to pure NC films (3.975%). Simultaneously, water contact angle measurements indicated an increase from 77° for pure NC film to 89° for NA film and 82° for NT film. All films exhibited superior transparency characteristics. Overall, NA films display excellent water resistance and transparency as well as good mechanical properties.

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.

Thermal decomposition behavior and kinetic study of nitrocellulose in presence of ternary nanothermites with different oxidizers

Nanothermites have recently attracted a great deal of interest in both military and civilian domains owing to their capability of igniting or exploding and releasing a significant quantity of heat via a redox reaction. In this study, three ternary nanothermites, which contain MgAl alloy as fuel and different metal oxides (MXOY = CuO, NiO, TiO2) as oxidizers, were prepared through the arrested reactive milling technique. These metastable intermolecular composites were introduced to nitrocellulose (NC), using a fast solution drying technique, to assess their catalytic behavior. The as-obtained energetic composites, namely, NC/MgAl-MXOY, were scrutinized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), powder X-ray diffraction (XRD), and differential scanning calorimetry (DSC). The ignition delay time of NC/MgAl-MXOY composite films was also determined, and the results revealed the positive effect of the introduction of nanothermite through the decrease of its value compared to pure NC. Using the isoconversional kinetic analysis, the Arrhenius parameters associated with the thermal decomposition of the as-obtained NC/MgAl-MXOY energetic composites films were also evaluated. The findings indicated that the choice of the oxidizer within the nanothermite composition significantly influences the decomposition behavior of the NC/MgAl-MXOY energetic composites. Based on the obtained results, the MgAl-CuO nanothermite provides better performance than MgAl-NiO and MgAl-TiO2 nanoparticles.

Fe2O3/ZIF-8 architectures with enhanced thermocatalytic performance for efficient degradation of nitrocellulose

Fe2O3/zeolitic imidazolate framework-8 (ZIF-8) architectures were successfully prepared by a polyvinylpyrrolidone (PVP)-assisted method, which can be as an effective potential catalyst for promoting the thermal degradation of nitrocellulose (NC). Thermal behavior and degradation kinetics of catalyst-NC mixtures were studied using the TG/DTG and DSC methods, and found that the Fe2O3/ZIF-8-NC pyrolysis possessed a total degradation of 77.96%, a maximum pyrolysis rate temperature of 194.5 °C, and the lowest activation energy of 179.4 ± 16.1 kJ mol−1, confirming a better thermocatalytic performance of Fe2O3/ZIF-8 when compared to Fe2O3 and ZIF-8 for NC thermolysis. Furthermore, it can be inferred from the isoconversional analysis, which employs a modified fitting algorithm, that catalyst-NC mixtures and pure NC adhere to the reconstructed “n-order” reaction models. This work showed how a catalyst of the metal oxide/metal-organic frameworks (MOFs) type could improve the pyrolysis of NC, which could serve as a significant reference for the development of additional catalysts of the metal oxide/MOFs for use in NC-based energetic materials.

Effect of metal chloride on thermal decomposition of nitrocellulose

The effect of various metal chlorides, namely FeCl3, AlCl3, CuCl2, and ZnCl2, on the thermal decomposition of nitrocellulose (NC) was studied using a synchronous thermal analyzer (STA). An aqueous solution of 10 mass% metal chlorides was added to NC and was then compared with pure NC. The results revealed that FeCl3 and AlCl3 promoted notable NC decomposition, but CuCl2 and ZnCl2 inhibited decomposition. Therefore, the addition of trivalent metal chlorides can increase the explosion risk in NC. By contrast, divalent metal chlorides can function as inhibitors. In addition, the kinetics of NC and NC mixed with metal chloride were determined. The addition of metal chlorides promoted or inhibited NC decomposition but did not change its reaction mechanism. This study provides crucial information for improving the safety of NC storage, transportation, and use.

Mordenite zeolite for scavenging nitroxide radicals and its effect on the thermal decomposition of nitrocellulose

ABSTRACT Nitrogen oxides (NO x ), which result from the decomposition of nitrocellulose (NC)-based solid propellants, promote the degradation of this later and alter its long-term stability. Thus, to avoid such situation and ensure a better stability, conventional stabilizers such as aromatic amines or urea compounds are usually added to the NC-based formulations. However, these latter may generate carcinogenic and toxic species that may negatively affect both human health and environment. Herein, based on its selective adsorption capacity of NO x , the stability potential of a porous inorganic compound, namely, mordenite (MOR), on nitrocellulose was assessed. Three NC-based samples (S1–S3) were prepared through the incorporation of 3 wt.% of stabilizing agents, i.e., S1: pure NC, S2: NC + DPA, and S3: NC + MOR. The effect on the stability of this inorganic compound with regard to pure NC has been highlighted utilizing stability tests and kinetic modeling. Beforehand, the compatibility of mordenite with nitrocellulose was initially checked by means of DSC and FTIR. Furthermore, the obtained results via Vacuum Stability Test (VST) and Bergmann–Junk (B&J) test demonstrated that S3 displayed a better stability than S1 and comparable behavior to S2. The determination of the kinetic triplet by isoconversional methods confirmed the effectiveness of MOR as a stabilizing agent. These findings claim that such inorganic compound may be used efficiently as a stabilizer for NC-based energetic formulations.

Green synthesis of CuO nanoparticles using Malva sylvestris leaf extract with different copper precursors and their effect on nitrocellulose thermal behavior

In this work, we have synthesized copper oxide nanoparticles (CuO NPs) by a precipitation method using leaf extract of Malva sylvestris as a stabilizing agent and three different copper precursors. The obtained CuO NPs have been characterized in detail by X-ray diffraction, ultraviolet–visible spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, and scanning electron microscopy. The as-prepared CuO NPs present the same pure chemical composition and belong to a monoclinic crystalline phase, with a spherical shape and crystallite diameter in the range of 19–26 nm, according to their precursors. Based on the differential scanning calorimetry (DSC) analyses performed at different heating rates, the thermal behavior of pure nitrocellulose (NC) and NC-CuO NPs composites has been investigated using four integral isoconversional kinetic methods. The obtained results show that, whatever the precursor, CuO NPs could be safely used as a catalyst for NC. Moreover, the added nanocatalysts could reduce the activation energy and slightly decrease the peak temperature. Finally, the thermal decomposition process of both NC and NC-CuO composites determined with Kissinger–Akahira–Sunose and Flynn–Wall–Ozawa) models, respectively, is classified as R2, contracting cylinder $$g \, \left( \alpha \right) \, = 1 - (1 - \alpha )^{\frac{1}{2}}$$ , whereas that of Trache–Abdelaziz–Siwani integral model is ascribed to F1/3 and F3/4 chemical reaction $$g \, \left( \alpha \right) \, = 1 - (1 - \alpha )^{\frac{2}{3}}$$ .

Further modification of oil–water separation membrane based on chitosan and titanium dioxide

In this paper, chitosan/nano-TiO2-modified liquid was coated on the surface of cellulose membrane by negative pressure suction filtration and a new method of preparing oil–water separation membrane was completed based on the pure nitrocellulose membrane. The performance parameters of cellulose composite membrane modified by chitosan and titanium dioxide with different concentration ratios were studied in terms of microstructure, element distribution and composition, wettability, using SEM, XPS, contact angle and other characterization methods. The optimal ratio of chitosan and titanium dioxide in the modified solution was selected to determine the optimal process parameters for the preparation of the new membrane. Because of the existence of nano-TiO2 particles in the new membrane, further study the effect of light on the membrane flux is required.

Organosolv lignins as new stabilizers for cellulose nitrate: Thermal behavior and stability assessment

Cellulose nitrate, commonly known as nitrocellulose (NC), and its corresponding propellants naturally decompose at normal conditions. To avoid early degradation, unexpected explosion, energy loss, and ensure a safe storage, stabilizing agents are often introduced within its compositions. Conventional stabilizers, such as aromatic amines like diphenylamine (DPA) and urea, can produce carcinogenic/toxic substances during propellants shelf life. Thus, a need for alternative stabilizing agents, which offer similar/better effectiveness and display a non/low toxicity, remains a challenge. This paper investigates the stabilizing effect of two organosolv lignins (OL), obtained from Aleppo pine (AP) and Eucalyptus globulus (EG), on NC. For this purpose, conventional stability tests and kinetic modeling are applied for different samples (S1-S4) using 3% of stabilizer, which are S1, pure NC; S2, NC + DPA; S3, NC + OL(AP); and S4, NC + OL(EG). Beforehand, FTIR spectroscopy and DSC analysis have been used to check the compatibility of these potential stabilizers and NC. The obtained results via Bergmann-Jung and vacuum stability tests suggested that the prepared mixtures are stable. The kinetic study based on DSC data using isoconversional methods shows that both stabilizers display a good stabilizing effect. The reactivity between the different organosolv lignins and NOx released during the degradation of NC has been well highlighted using FTIR and TGA analyses. Hence, these efficient, environmentally friendly and readily available substances can be effectively used as stabilizers for NC-based formulations.

The Effects of Aniline Stabilizers on Nitrocellulose Based on Isothermal Thermal Decomposition

AbstractThe effects of various aniline stabilizers on the thermal stability of nitrocellulose (NC) were investigated via isothermal thermal decomposition dynamics. The pressure‐time curves of NC/stabilizer composites were found to have a distinct inflection point, which was not observed on the pressure‐time curves of NC. The effects of stabilizers on the isothermal thermal decomposition kinetics of NC were evaluated using Arrhenius equation and model‐fitting method, and the effect of stabilizers on the storage time of NC was estimated using Berthelot equation. Results showed that the activation energy of NC/MNA, NC/ENA, NC/i‐PNA, and NC/n‐BNA before the inflection point were 162.9, 153.3, 147.4, and 150.6 kJ mol−1, respectively, which were significantly increased compared with that of pure NC (144.7 kJ mol−1). Furthermore, the time required for the decomposition extent of NC/MNA, NC/ENA, NC/i‐PNA, and NC/n‐BNA to reach 0.1 % were 24.9, 11.2, 16.7, and 11.2 years, respectively, at 298.15 K, which was longer than that required of NC (10.6 years). UV‐vis revealed that the stabilizers were almost consumed when the NC/stabilizer thermal decomposition pressure‐time curve reached the inflection point. Based on the above results, the stability order was MNA>i‐PNA>ENA>n‐BNA as the criterion for time of the inflection point.

Analysis and characterization of nitrocellulose as binder optimized by 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide

Nitrocellulose (NC), a highly energetic compound, is widely used in nitrolacquer, celluloid, binder, propellants, and explosives. Many studies have focused on the inflammability and instability of NC, but few have investigated its use as a propellant binder. To optimize the properties of NC as a propellant binder, this study introduced 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([Bmim][NTf2]) as an additive. This study focuses on the thermal pyrolysis behavior and decomposition mechanism of pure NC (NC-P), NC-NTf2 (i.e., NC mixed with [Bmim][NTf2]), and NC-NTf2-eth (i.e., NC mixed with 30% [Bmim][NTf2] and 70% ethanol). First, the thermal degradation processes of NC and [Bmim][NTf2] were investigated using thermogravimetric analysis. In addition, the essential thermodynamic parameters of NC-P, NC-NTf2, and NC-NTf2-eth were obtained by differential scanning calorimetry, and the apparent activation energies were evaluated using the Starink method and Friedman method. The results show that NC-NTf2 has low onset decomposition temperature, low activation energy, and high energy release rate. Moreover, NC-P, NC-NTf2, and NC-NTf2-eth were characterized by scanning electron microscopy and Fourier transform infrared spectroscopy to verify and interpret the thermal analysis results obtained.

Interaction and mechanism of nitrocellulose and N-methyl-4-nitroaniline by isothermal decomposition method

The influence of N-methyl-4-nitroaniline (MNA) on the thermal stability of nitrocellulose (NC) was investigated via an isothermal decomposition dynamics research method. The Arrhenius equation and model-fitting were used to calculate the thermal decomposition kinetic parameters of NC and MNA/NC (3 wt%) composite. Results showed that the thermal decomposition activation energy of NC/MNA (3 wt%) was significantly increased compared with that of pure NC, indicating that the thermal stability of NC was increased with stabilizer MNA addition. Subsequently, the storage life of NC and MNA/NC (3 wt%) composite was estimated using Berthelot equation. It was found that if the decomposition extent reaches 0.1% as the end of life criterion, 3 wt% stabilizer MNA addition significantly extended the storage life of NC from 10.57 to 24.9 years at ambient temperature (298.15 K) with the life extension rate reaching 135.6%. Furthermore, the intermediate product produced by MNA and NC action was extracted and characterized via UV–Vis, HPLC, 1H NMR, FT-IR, and LC–MS, and a possible stabilization mechanism of MNA to NC was proposed.

Compatibility and thermal decomposition mechanism of nitrocellulose/Cr2O3 nanoparticles studied using DSC and TG-FTIR.

Nano metal oxides are common combustion catalysts for enhancing the burning rate of solid propellants. Cr2O3 nanoparticles (NPs) are efficient combustion catalysts for the pyrolysis of energetic components. In this study, Cr2O3 NPs were synthesized via a modified sol–gel method and further used for studying the thermal decomposition of nitrocellulose (NC). Differential scanning calorimetry (DSC) and thermogravimetry-Fourier-transform infrared spectroscopy (TG-FTIR) analyses indicate that the Cr2O3 NPs can be safely used with NC and the mechanism of the reaction between Cr2O3/NC and pure NC follows the Avrami–Erofeev equation: f(α) = 3(1 − α)[−ln(1 − α)]1/3/2. The peak temperature and activation energy (Ea) for the thermal decomposition of Cr2O3/NC are lower than those of pure NC. NO2 was detected at a lower temperature after NC was mixed with Cr2O3 NPs; this indicated the catalytically accelerated bond cleavage of NC by Cr2O3 NPs.

Thermal behavior of nitrocellulose with different aging periods

To further understand the aging process of energetic materials such as nitrocellulose (NC), aging treatment of NC samples was performed by a constant temperature chamber and non-isothermal experiments were performed by a TG-DSC analyzer. Also, scanning electron microscope was utilized to detect the morphological changes of NC in different forms. The results revealed that, with the increasing aging time, the decomposition properties including mass loss, decomposition temperature, heat production rate and heat of decomposition exhibit significantly different trends for the two forms of NC. Furthermore, the thermal kinetic parameters of pure NC were calculated based on Kissinger method. It is found that pure NC has the highest thermal instability at the aging time of 24 days under the aging temperature of 90 °C, and the stability of NC will increase when the aging time exceeds 32 days.

Preparation and Sensitivity Property of Nitrocellulose/Silica Composite with Silica Gel as Coating Layer

AbstractThe safety performance of propellants is one of the important issues that must be considered in their application and it is mainly determined by their sensitivity. Thus, the reduction of the sensitivity exhibited by propellants is an effective measure to improve their safety. The sensitivity of traditional propellants is partly resulted from nitrocellulose, and preparation and application of less sensitive nitrocellulose can reduce their sensitivity. However, the nitrocellulose has gained little development from the invention on the sensitivity research. The surface of nitrocellulose was grafted with the silica gel by sol‐gel method to prepare an insensitive nitrocellulose in the paper. The product was characterized by FT‐IR, SEM, XRD, XPS, TGA, DSC and sensitivity tests. Results show that the nitrocellulose surface is coated with the silica gel successfully, and its crystal form is not affected by silica gel. Furthermore, the impact sensitivities of NC/SiO2 composites are reduced significantly in comparison with pure nitrocellulose.

Effect of plasticizer dibutyl phthalate on the thermal decomposition of nitrocellulose

This paper aims to investigate the effects of plasticizer dibutyl phthalate (DBP) on the thermal decomposition of nitrocellulose (NC) by using a series of analytical apparatuses. In the present study, the detailed structures of pure NC (NC-P) and NC with DBP (NC-D) were revealed by scanning electron microscope. It was found that the fibers in NC-D are more closely aligned than those in NC-P, which makes the thermal behaviors of NC-D different from NC-P. The thermal stability of both NC-P and NC-D was examined by means of simultaneous TG-DSC apparatus (STA). Three different kinetic methods (Kissinger–Akahira–Sunose method, Ozawa–Flynn–Wall method, and Friedman method) were applied for determining the activation energy E of these two NC samples. Moreover, the experimental data were compared with sigmoidal models and pre-exponential factor was calculated by compensation effect. Besides, in situ Fourier transform infrared (FTIR) and a TGA instrument coupled with Frontier FTIR spectrometer were employed to investigate the characteristic functional groups of decomposition residues and gaseous products at different temperatures, respectively. The results show that NC-P and NC-D have similar decomposition products and decomposition mechanisms.

Experimental study on the fire characteristics of typical nitrocellulose mixtures using a cone calorimeter

To further understand the safety performance of energetic materials such as nitrocellulose (NC) mixtures, it is necessary to obtain the fire properties of commonly used NC mixtures. In the present study, an in situ calorimeter was employed to investigate the fire characteristics of pure NC, NC-plasticizer mixture and two NC-humectant mixtures, namely NC-isopropanol and NC-ethanol mixtures. The plasticizer (dibutyl phthalate) and humectants (ethanol or isopropanol) can effectively reduce the fire risk of NC. NC-plasticizer is more risky than NC-humectants in the burning process. Compared with the NC with isopropanol, the NC with ethanol exhibits higher fire risk. Also, the thermogravimetric (TG) curves of four NC samples were measured by a TG analyzer. The curves indicate that the decomposition of pure NC is more dramatic than NC mixtures, and the NC with plasticizer dibutyl phthalate can decompose in advance.