Thermal Degradation Studies Research Articles

Development of Ni–Al2SiO5/Ni–SiO2 Coating Doped with Benzotriazole: Corrosion, Structural Evolution and Thermal Degradation Study

Development of Ni–Al2SiO5/Ni–SiO2 Coating Doped with Benzotriazole: Corrosion, Structural Evolution and Thermal Degradation Study

Preparation, thermal degradation, and rheology studies for polylactic acid (PLA) and palm stearin (PS) blend: A review

In various types of applications, poly(lactic acid) (PLA) might be considered one of the potential alternatives to petrochemical-derived polymers such as polypropylene. However, PLA's disadvantages, such as its brittleness, heat characteristics, and degrading stability, restrict its use. To improve the aforementioned PLA qualities, polymerization, plasticization, and PLA blends are all being investigated. This research examines the production of PLA using various bio-based plasticizers to enhance the qualities of PLA, such as satisfying industrial requirements and recognising the limitations of each modification. Due to favourable results from other palm oil-based plasticizers described in various polymer modification works, palm stearin is a new candidate considered to be a strong option as a plasticizer to overcome the limits of PLA. Palm stearin is a co-product of palm olein and, it is always traded at a discount to palm oil and palm olein. Considering PLA and palm stearin are potentially prepared by melt-blending, the thermal properties such as glass transition temperature (Tg), cold crystallization temperature (Tcc), and the melting temperature (Tm) are critical to be investigated further for this blend because of the partial crystallization properties of palm stearin, which are characterized by differential scanning calorimetry (DSC) under a nitrogen atmosphere. Characterizations such as torque, rheology, and Fourier Transform Infrared Spectroscopy (FTIR) were also reviewed on the plasticized PLA to study the compatibility and the biodegradable of this plasticized PLA. From this review, a suitable processing design for PLA and palm stearin blend was determined, and the thermal and rheology characteristics for PLA and the bio-plasticizer were successfully reviewed.

Synthesis and characterization studies of polypyrrole/iron tungstate nanocomposites for interfacial water evaporation

PPy-FeWO4 composites were synthesized by polymerization of pyrrole in presence of varying weight percentage of FeWO4 nanoparticles using FeCl3 as both catalyst and dopant. The synthesized polymer composites were characterized by FTIR, XRD, FESEM-EDAX, TEM and TGA analysis. The XRD and FTIR analysis confirmed showing near pure samples were achieved. The FESEM-EDAX and TEM studies showed the presence of FeWO4 nanoparticles which were well dispersed in the polymer matrix. The thermal degradation studies showed similar stability of polymer matrix in the presence of nanoparticles. Interfacial solar water evaporation devices were fabricated by depositing the polymer composite on floatable PU sponges. The studies revealed that 50-50 wt% PPy-FeWO4 showed maximum solar to vapour conversion up to 86% with an evaporation rate up to 1.2 kg m−2 hr−1.

Thermal degradation studies of 2-hydroxy-4-methoxy acetophenone, guanidine and formaldehyde copolymer

The 2-hydroxy 4-methoxyacetophenone-guinidine-formaldehyde (HMAGF) copolymer was synthesized by the using monomers of 2-hydroxy-4-methoxyacetophenone, guanidine and formaldehyde in 2M hydrochloric acid medium at 124 °C in 1:1:2M proportions of the three reactants. The characterization of the newly synthesized HMAGF copolymer was confirmed by basic investigation and different spectral techniques like UV-Visible, FTIR, and 1H NMR spectroscopy. The warm debasement investigations of the copolymer were done by thermogravimetric examination (TGA). Sharp Wentworth and Freeman Carroll methods were utilized to calculate thermodynamic parameters like activation energy (Ea), Change in entropy (ΔS), change in free energy (ΔF), change in entropy (S*), the frequency factor. (Z). The activation energy determined by the Sharp Wentworth and Freeman Carroll methods are almost same. The order of reaction is found to be 0.8.

Thermal Degradation Studies of Copolymer Derived from 2,2’-Dihydroxybiphenyl, Ethylenediamine and Formaldehyde

Copolymer (2,2’-BPEDF) was synthesized with molar ratio 3:1:5 of monomer 2,2’- dihydroxybiphenyl (BP), ethylenediamine (ED) and formaldehyde (F) by condensation polymerization, in acidic medium and refluxing in oil bath at 1200C for 5 h. Composition and structure of organic copolymer have been determined by elemental analysis and molecular weight determination by non-aqueous conductometric titration method. The UV-visible, FTIR and proton nuclear magnetic resonance (1H NMR) spectra were studied to elucidate the structure. The surface features and crystalline behaviour of the copolymer was analysed by scanning electron microscope (SEM).Non isothermal thermogravimetric analysis for determination of their mode decomposition and relative thermal stability, Energy of activation, frequency factor and order of reaction have been calculated by Sharp-Wentworth (SW) and Freeman-Carroll (FC) methods. Energy of activation determined by Sharp-Wentworth and Freeman-Carroll methods are in agreement with each other. The order of reaction is found to be 0.98.

Forced Degradation Study for Simultaneous Quantification of Aspirin and Omeprazole in Pharmaceutical Dosage form by RP-HPLC

Aims: To study force degradation of aspirin and omeprazole simultaneously by RP-HPLC method
 Study design: RP-HPLC method was used to measure % degradation.
 Place and Duration of Study: Study was carried out at center of excellence, G.I.D.C., vapi-396195, Gujarat, India between June 2019 to march 2020.
 Methodology: A force degradation study of aspirin and omeprazole was carried out simultaneously. The drugs were subjected to various degradation conditions like hydrolysis by acid and base, Oxidative degradation, and thermal degradation study.
 Results: For acidic condition, the degradation was found to be 32.63 % for aspirin and 61.64 % for omeprazole. For basic condition, the degradation was found to be 10.17 % for aspirin and 4.29 % for omeprazole. By oxidative hydrolysis, the aspirin was degraded by 15.48 % and omeprazole was degraded by 26.38 %. By thermal degradation, 0.37 % degradation was observed for aspirin and 4.32 % degradation for omeprazole.
 Conclusion: In this proposed method the retention time for drug is less than 8 min, which is less then available method. For omeprazole, strong degradation was observed in acidic conditions and mild in basic hydrolysis conditions. For aspirin, more degradation was observed in basic conditions than acidic hydrolysis. Both drugs were degraded in oxidative conditions using 3% H2O2. Omeprazole degraded more than aspirin by dry heat degradation. The method was successfully applied for the quantitative determination of both Active Pharmaceutical Ingredients.

Biofuels and biochars production from agricultural biomass wastes by thermochemical conversion technologies: Thermogravimetric analysis and pyrolysis studies

Abstract In this paper, thermal degradation (TGA) and pyrolysis studies of sunflower shell biomass (SSB), eucalyptus biomass (EB), wheat straw biomass (WSB), and peanut shell biomass (PSB) were carried out using the thermogravimetric analysis and stainless steel tubular reactor. Thermal degradation of all biomass wastes was examined at a heating rate of 10 °C/min in nitrogen atmosphere between 20 and 800 °C. Experiments of pyrolysis were carried out in a tubular reactor from 300 to 700 °C with a heating rate of 10 °C/min, a particle size of 0.1–0.3 mm and nitrogen flow rate of 100 mL.min−1, which the aim to study how temperature affects liquid, solid, and gas products. The results of this work showed that three stages have been identified in the thermal decomposition of SSB, EB, WSB, and PSB wastes. The first stage occurred at 120–158 °C, the second stage, which corresponds to hemicellulose and cellulose's degradation, occurred in temperatures range from 139 to 480 °C for hemicellulose, and from 233 to 412 °C for cellulose, while the third stage occurred at 534–720 °C. It was concluded that temperature has a significant effect on product yields. The maximum of bio-oil yields of 37.55, 30.5, 46.96, and 50.05 wt% for WSB, PSB, SSB, and EB, were obtained at pyrolysis temperature of 500 °C (SSB, PSB, and WSB) and 550 °C (EB). Raw biomass, solid and liquid products obtained were characterized by elemental analysis, Fourier transformed infrared spectroscopy (FT-IR), nuclear magnetic resonance spectroscopy (NMR), and x-ray diffraction (XRD). The analysis of solid and liquid products showed that bio-oils and bio-chars from agricultural biomass wastes could be prospective sources of renewable fuels production and value added chemical products.

Thermal degradation study of polymethylmethacrylate with AlI3 nanoadditive.

Organic polymers in the process of thermal degradation produce a lot of toxic fragments. In this work, we designed a new method of degradation of polymethylmethacrylate (PMMA) materials with aluminum triiodide nanoadditives (AlI3 NAs). In the present research work, a thermal degradation study of PMMA blends with AlI3 NAs was carried out by using a specially designed pyrolytic assembly. Different blends of PMMA with AlI3 (P0, P3, P6, P9, P12, and P15) were prepared by changing the concentration of AlI3 NAs from 0% to 15%. FTIR and TGA studies show the stability of polymers with AlI3 NAs. Scanning electron microscopy analysis shows All3 spread uniformly at nanoscale throughout the polymer matrix. Horizontal burning test (HBT) test confirms that polymer burning is retarded with AlI3 NAs.

Synthesis, Crystal structure and thermal reactivity of [(N2H5)2Mn0.20Ni0.80(C2O4)2](H2O)2: A novel precursor to nickel-manganese oxide

A novel solid solution precursor, [(N 2 H 5 ) 2 Mn 0.20 Ni 0.80 (C 2 O 4 ) 2 ](H 2 O) 2 has been prepared and characterized by hydrazine analysis, CHN analyses, infrared spectrum, thermal degradation studies and single-crystal X-ray diffraction analysis. The single-crystal X-ray analysis reveals that the complex is centro-symmetric with distorted octahedral geometry. The metal center is occupied by both Mn 2+ and Ni 2+ ions coordinated by four carboxylate oxygen atoms from two bidentate oxalate 2− anions and two axial hydrazinium ions through nitrogen atoms which clearly define the distorted octahedral structure. Simultaneous TG-DTA of the complex shows three steps decomposition resulting in the formation of the mixed metal oxide (MnNi 6 O 8 ) as an end product. The chemical composition of mixed metal oxide obtained was confirmed from energy dispersive X-ray (EDX) data. Atomic force microscopy (AFM) reveals that the nanocomposite is formed as aggregates. The zeta potential (ζ) value is 30.2 mV, which indicates the high stability of the oxide.

Replacement of volatile styrene by flame retardant crosslinking diluents in unsaturated polyester resins

<p indent="0mm">The flammability of unsaturated polyester resins (UPR) and the volatility of their toxic styrene diluents pose serious safety risks. In this paper, three non-volatile flame retardant diluents (PBHA, POHA and PSHA) containing different phosphorus structures were synthesized, which can completely replace styrene and provide excellent flame retardant performance for UPR. Their structures were characterized by FTIR and NMR (¹H, ³¹P). The potential of synthesized reactive diluents as substitutes in UPR and their glass fabric reinforced composites was assessed through volatility, processability, curing kinetics and gel contents. Meanwhile, by comparing the effects of different phosphorous structures, PBHA diluent can bring best flame retardant efficiency. UP/PBHA reached V0 in UL-94 and 28% of LOI. The PHRR and THR of UP/PBHA were decreased by 64.06% and 61.54% compared with neat UP/St. For glass fabric/UPR composites, GF/UP/PBHA also reached V0 rating, and LOI was as high as 38%. Meanwhile, through the study of thermal stability, thermal degradation and combustion process, it was found that PBHA mainly worked in gas phase to capture H<x content-type="symbol">×</x> and HO<x content-type="symbol">×</x>, supplemented by promoting formation of dense carbon layer in condensed phase to isolate oxygen and thermal radiation.

Combustion of a Solid Recovered Fuel (SRF) Produced from the Polymeric Fraction of Automotive Shredder Residue (ASR).

The use of alternative fuels derived from residues in energy-intensive industries that rely on fossil fuels can cause considerable energy cost savings, but also significant environmental benefits by conserving non-renewable resources and reducing waste disposal. However, the switching from conventional to alternative fuels is challenging for industries, which require a sound understanding of the properties and combustion characteristics of the alternative fuel, in order to adequately adapt their industrial processes and equipment for its utilization. In this work, a solid recovered fuel (SRF) obtained from the polymeric fraction of an automotive shredder residue is tested for use as an alternative fuel for scrap preheating in an aluminium refinery. The material and chemical composition of the SRF has been extensively characterized using proximate and ultimate analyses, calorific values and thermal degradation studies. Considering the calorific value and the chlorine and mercury contents measured, the SRF can be designated as class code NCV 1; Cl 2; Hg 2 (EN ISO 21640:2021). The combustion of the SRF was studied in a laboratory-scale pilot plant, where the effects of temperature, flow, and an oxidizer were determined. The ash remaining after combustion, the collected liquid, and the generated gas phase were analysed in each test. It was observed that increasing the residence time of the gas at a high temperature allowed for a better combustion of the SRF. The oxidizer type was important for increasing the total combustion of the vapour compounds generated during the oxidation of the SRF and for avoiding uncontrolled combustion.

A Study of Thermal Degradation and Fire Behaviour of Polymer Composites and Their Gaseous Emission Assessment

The use of polymer composite materials in the aeronautics and automotive sectors has increased dramatically, and their fire behaviour has become a critical parameter in terms of fire safety. On this premise, it is critical to demonstrate that these composite materials constitute elements whose safety justifies a high level of confidence. This is based on their combustibility and the rate at which flammable and toxic gaseous species are emitted. Thus, strict fire safety regulations are enforced by the relevant authorities concerned because of their potential fire risk. This study analysed papers published between 1970 and 2021 that described the devices used to characterise the thermal behaviour of composite materials at various scales. The objective was to highlight the thermophysical phenomena, making it possible to accurately assess the flammability and thermal stability of polymer composite materials. The results of this research reveal that the small-scale facilities provide detailed understanding and mastery of the thermal reaction properties of the composites. While with the medium scale, the extended fire reaction parameters, which are the key indicators of the fire safety performance, can be determined. On a large scale, the tests were carried out using devices such as the NexGen burner recommended by the FAA. Therefore, with such assays, it is possible to assess the rates of thermal degradation as well as quantified pyrolysis gases. However, compared to other scales, there were very few works on a large scale. In addition, by focusing on the polluting nature of synthetic composite materials, there is also few research studies aimed at designing new polymer composite materials from biological sources.

Physical, thermal, and mechanical properties of highly porous polylactic acid/cellulose nanofibre scaffolds prepared by salt leaching technique

Abstract This study aimed to prepare and characterise polylactic acid (PLA) reinforced with cellulose nanofibre (CNF) from a Pennisetum purpureum-based composite scaffold and determine its structural and mechanical properties. Porous scaffolds with CNF compositions of 5‒20 wt% in the PLA matrix were developed using solvent casting and particulate leaching of its porogen at 90 wt% of loadings. Morphology studies using field emission scanning electron microscopy revealed that the scaffolds had well-interconnected pores with an average pore size range of 67‒137 µm and porosity &gt;76%. X-ray diffraction confirmed the interconnectivity and homogeneity of the pores and the fibrous structure of the scaffolds. The compressive strength of the fabricated scaffolds varied between 2.34 and 6.66 MPa, while their compressive modulus was between 1.95 and 6.04 MPa for various CNF contents. Furthermore, water absorption and thermal degradation studies showed that the scaffold had good hydrophilicity and improved thermal stability. These findings highlight the need to modify the pore structure and mechanical performance simultaneously for tissue engineering. Thus, this study concludes that the developed PLA scaffolds reinforced with CNF from Pennisetum purpureum are potential candidates for cell attachment and extracellular matrix generation.

ПІДВИЩЕННЯ ВОГНЕЗАХИСНОЇ ЕФЕКТИВНОСТІ ІНТУМЕСЦЕНТНИХ ЕПОКСИДНИХ ПОКРИТТІВ СПОЛУКАМИ ІНТЕРКАЛЬОВАНОГО ГРАФІТУ

Investigation of the effect of nitrate oxide graphite on the parameters of char layer, obtained from the system of ammonium polyphosphate / melamine / pentaerythritol / epoxy resin under the influence of temperatures of 200–800 °С. Methodology. A fire retardant mixture was chosen as a model intumescent system ammonium polyphosphate / melamine / pentaerythritol. As a polymer component was used bisphenols A / F epoxy resin together with a polyamidoamine hardener. Nitrate oxide graphite was obtained by oxidation of natural scaly graphite with fuming nitrogen acid. The effect of impurities of nitrate oxide graphite was determined by thermogravimetry on the intumescence coefficient of intumescent compositions and the mass of the char residue intumescent compositions in temperature range of 200–800 °С. Findings. The influence of nitrate oxide graphite on the characteristics was studied of char layer of epoxy intumescent system ammonium polyphosphate / melamine / pentaerythritol / epoxy resin. The study of thermal oxidative degradation was carried out intumescent compositions in the temperature range 200–800 °С. It was shown that intercalated graphite compounds increase the thermal stability of the formed char layer at temperatures &gt; 600 °С. Determined intumescence coefficients and thermogravimetric analysis of modified intumescent systems was performed nitrate oxide graphite with different degrees of intercalation, in the conditions of 200–800 °С. It was established that the optimal parameters of the char layer are in terms of volume intumescence coefficient and mass of the char residue are provided by graphites, which contain 15–25% of intercalant in its composition. But the results obtained allow us to determine nitrate oxide graphite as a promising modifier of epoxy intumescent systems to increase its fire protection efficiency. Originality. The influence of degree of intercalation of nitrate oxide graphite was studied on the characteristics of char layer of epoxy intumescent system for the first time. Practical value. The optimal content of intercalant in nitrate oxide graphite was established for the development of formulations of intumescent epoxy coatings with increased fire retardant properties.

Thermal degradation of metabolites in urine using multiple isotope-labelled internal standards for off-line GC metabolomics - effects of injector and oven temperatures

Thermal processes are widely used in small molecule chemical analysis and metabolomics for derivatization, vaporization, chromatography, and ionization, especially in gas chromatography mass spectrometry (GC/MS). An optimized derivatization protocol has been successfully applied using multiple isotope labelled analytical internal standards of selected deuterated and 13C selected compounds, covering a range of different groups of metabolites for non-automated GC metabolomics (off-line). Moreover, the study was also realized in a pooled urine sample, following metabolic profiling. A study of thermal degradation of metabolites due to GC inlet and oven programs (fast, slow) was performed, where the results indicated that both GC oven programs (fast and slow) negatively affected the thermal stability of the metabolites, while the fast-ramp GC program also suppressed MS signals. However, the use of multiple internal standards can overcome this drawback. The application of extended temperature ramp GC program presented identical behaviour on metabolite stability and better chromatographic separation combined with much lower signal suppression, compared to a short temperature ramp program. No effects were observed for organic acids, fatty acids, sugars and sugar alcohols, while significant differences were observed for amino acids. GC metabolomics is a strong tool that can facilitate analysis, but special attention is required for sampling handling and heating, before and during the GC analysis. The use and application of multiple multi-group internal standards is highly recommended.

N-Nitrosodimethylamine (NDMA) Formation from Ranitidine Impurities: Possible Root Causes of the Presence of NDMA in Ranitidine Hydrochloride.

N-Nitrosodimethylamine (NDMA) is a probable human carcinogen. This study investigated the root cause of the presence of NDMA in ranitidine hydrochloride. Forced thermal degradation studies of ranitidine hydrochloride and its inherent impurities (Imps. A, B, C, D, E, F, G, H, I, J, and K) listed in the European and United States Pharmacopeias revealed that in addition to ranitidine, Imps. A, C, D, E, H, and I produce NDMA at different rates in a solid or an oily liquid state. The rate of NDMA formation from amorphous Imps. A, C, and E was 100 times higher than that from crystalline ranitidine hydrochloride under forced degradation at 110 °C for 1 h. Surprisingly, crystalline Imp. H, bearing neither the N,N-dialkyl-2-nitroethene-1,1-diamine moiety nor a dimethylamino group, also generated NDMA in the solid state, while Imp. I, as an oily liquid, favorably produced NDMA at moderate temperatures (e.g., 50 °C). Therefore, strict control of the aforementioned specific impurities in ranitidine hydrochloride during manufacturing and storage allows appropriate control of NDMA in ranitidine and its pharmaceutical products. Understanding the pathways of the stability related NDMA formation enables improved control of the pharmaceuticals to mitigate this risk.

Compositional and kinetic study of thermal degradation of kerogen using TG‐FTIR, NMR, and microscopic study

AbstractUnderstanding the thermal maturation mechanism of kerogen has both industrial and scientific significance. Here, kerogen extracted from Indian oil shale of Upper Assam basin is subjected to TG‐FTIR analysis to study the thermal decomposition behavior of isolated kerogen and compared with oil shale sample. Kinetic study of kerogen was performed on thermogravimetric data using isoconversional methods. The mean apparent activation energy values were found in the range of 219 to 236 kJ/mol. The reaction models were identified as first‐order and A2 nucleation models. The obtained kinetic parameters were validated by reconstruction of conversion profiles. Comparison of oil derived from kerogen with shale oil, and solvent‐extracted bitumen using NMR analysis showed that kerogen initially matures into bitumen, and thereafter, gets converted to oil and gas in the presence of inherent minerals. The predicted degradation mechanisms of kerogen from the parent oil shale sample were examined using microscopic study.

Hydroxyquinoline copolymers synthesis, characterization and thermal degradation studies

In the flow research article, we report the amalgamation of a new natural copolymer of 8-hydroxyquinoline-5-sulphonic acid, guanidine, and formaldehyde in the molar proportion 1:1:2 inside seeing 2 M hydrochloric corrosive as an impetus by polycondensation strategy. The copolymer 8-HQ-5-SAGF was portrayed by elemental examination, Ultra-Visible, Infrared spectra, 1H and 13C Nuclear magnetic resonance spectroscopy. Furthermore, we have examined the non isothermal thermogravimetric examination for assurance of relative warm stability and their mode deterioration, Energy of initiation, frequency factor and request of response was measured by Freeman-Carroll (FC) and Sharp- Wentworth (SW) techniques. Energy of enactment controlled by Sharp-Wentworth and Freeman-Carroll strategies are in acceptable concurrence with one another. The surface component of copolymer is inspected by filtering electron microscopy.

Thermal degradation and kinetics stability studies of oil palm (Elaeis Guineensis) biomass-derived lignin nanoparticle and its application as an emulsifying agent

In this paper, lignin was extracted from oil palm empty fruit branch fibers by using a soda pulping process. The homogenizing method was used to reduce the size of lignin into nanoparticles. Four different homogenization shear speeds i.e. 6400, 8400, 10,400, and 12,400 rpm were explored to control the particle size of lignin. Lignin nanoparticles (LNPs) were characterized using FT-IR, UV, TEM, SEM, zeta potential, kinetic thermal degradation, and toxicological analyses. The stability of water-in-oil (W/O) emulsions was characterized by visual observation and cross-polarized microscopy (CPM). The FT-IR results showed similar spectra of all the samples while the particle distribution from TEM demonstrated up to 98% of the samples are in the nano range. The zeta potential of LNP12* (emulsifying agent produced from LNP12 at 12,400 rpm) was observed at |−32.0| mV and found to be the best among all samples to stabilize W/O emulsion at a ratio of 30:70 (water to oil) as a result from creaming index percentage and CPM. Therefore, LNP12 was further analyzed for shelf-life prediction using a kinetic thermal degradation study. Flynn-Wall-Ozawa and Kissinger methods were used in kinetic thermal degradation to determine the activation energy (Ea) of LNP12. It was found that both methods are in good agreement. The Ea value of LNP12 demonstrated better stability and longer shelf-life (around 20 months) at a temperature below 35 °C. LNP12 showed to be safe both, in vitro and in vivo toxicological methods at a concentration below 2000 mg/kg.

Synthesis and Thermal Degradation Study of Polyhedral Oligomeric Silsesquioxane (POSS) Modified Phenolic Resin.

In this paper, a new polyhedral oligomeric silsesquioxane containing a phenol group (POSS-Phenol) is prepared through the Michael addition reaction, which is added to the synthesis of phenolic resin as a functional monomer. Infrared spectroscopy (IR) is used to demonstrate the chemistry structure of the synthesized POSS modified phenolic resin. After introducing POSS into the resole, a comprehensive study is conducted to reveal the effects of POSS on the thermal degradation of phenolic resin. First, thermal degradation behaviors of neat phenolic resin and modified phenolic resin are carried out by thermogravimetric analysis (TGA). Then, the gas volatiles from thermal degradation are investigated by thermogravimetric mass spectrometry (TG-MS). Finally, the residues after thermal degradation are characterized by X-ray diffraction (XRD). The research indicates that POSS modified phenolic resin shows a better thermal stability than neat phenolic resin, especially at high temperatures under air atmosphere. On the one hand, the introduction of the POSS group can effectively improve the release temperature of oxygen containing volatiles. On the other hand, the POSS group forms silica at high temperatures under air, which can effectively inhibit the thermal oxidation of phenolic resin and make phenolic resin show a better high-temperature oxidation resistance.