Sustainable Bacterial Cellulose-Based Composite Aerogels with Excellent Flame Retardant and Heat Insulation

doi:10.21203/rs.3.rs-2072936/v1

Download PDF

Research Article

Sustainable Bacterial Cellulose-Based Composite Aerogels with Excellent Flame Retardant and Heat Insulation

https://doi.org/10.21203/rs.3.rs-2072936/v1

This work is licensed under a CC BY 4.0 License

Journal Publication

published 29 Aug, 2023

Read the published version in Cellulose →

You are reading this latest preprint version

Bacterial cellulose (BC) aerogels with ultralight, low density, and low thermal conductivity are hopeful candidates for environmentally friendly heat insulating materials. However, the application of BC in packaging and building as a heat nonconductor is seriously limited by its flammable characteristics. Hence, we report a moderate approach to fabricating a flame retardant and heat-insulating composite aerogel by introducing zinc borate (ZB) particles into BC via an ultrasound-assistant deposition process. The in situ synthesis of ZB particles resulted in the separation of single fibers from fiber bundles in BC instead of damaging its homogeneous porous structure, improving its thermal stability by weakening the convective intensity of heat rays. The heat release capacity of the prepared composite aerogel was only 8 J·g^− 1 k^− 1, exhibiting excellent flame retardancy. The probable mechanism proposed to be that the dehydration of ZB particles lowered the surface temperature by releasing the bound water, and simultaneously produced metallic oxides (ZnO and B₂O₃) for retarding the spread of heat and isolating the flammable fibrils within the combustion area. Because of the natural substrate and simple process, the present approach has potential applications for industrial-scale production of green and flame retardant material.

Bacterial cellulose

Zinc borate

Flame retardant

Heat insulating

Aerogel

Bacterial cellulose (BC) aerogel is a kind of maintainable material, coalescing the exceptional attributes of extremely porous aerogels, such as ultralight, high specific surface area and insulation, low density and thermal conductivity, and also has advantages in biodegradability and biocompatibility (Chen et al. 2011). The fiber diameter of BC is only about 1/100 of that of plant fibers since BC is the metabolic product of cells and presents an independent filamentous structure. Due to its excellent characteristics, including high flexibility, water capacity, modulus of elasticity, crystallinity, surface area, and environmentally friendly (non-toxic and biodegradable), BC is attracting great attention both in academia and industry for exploring its potential applications. In recent years, extensive efforts have been attempted to apply BC in wastewater treatment, tissue engineering, flexible devices, and building materials (Yu et al. 2017; Cai et al. 2014; Xu et al. 2017, Wicklein et al. 2015). Although BC aerogel presents good thermal insulation performance from its plentiful inner porous network, it is easy to catch fire and burn out, limiting its applications as domestic appliances or building materials (Han et al. 2015). Improving the fire-resistant performance of BC aerogel is becoming the primary subject of multitudinous interesting scientific studies. One of the practical tactics for this purpose is the addition of other agents, including graphene (Zhang et al. 2012), halogens (Chen et al. 2013), clay (Pan et al. 2018), phosphorus (Liu and Wang 2009), nitrogen, organic polymers (Viggiano et al. 2017), and metal nanoparticles, by in situ forming or doping inside the BC network (Bober et al. 2014). Collaborative additives could take the shape of a dense protecting layer on the surface and separate oxygen to reach a flame retardant effect.

Cellulose-based composite aerogels with improved flame retardancy have been prepared by mixing aluminum hydroxide (Al₂O₃) nanoparticles (He et al. 2018). A similar approach has recently been adopted for in situ synthesis of magnesium hydroxide (Mg(OH)₂) nanoparticles in a cellulose network gelled in alkaline urea solution. The resulting aerogel exhibited self-extinguishing behavior within 40s, and the increased thermal conductivity from 56 to 81 mW/m·K was only achieved by the high loading of Mg(OH)₂ (Han et al. 2015). By impregnating a CNF suspension with graphene oxide and clay mineral sepiolite nanorods, strong anisotropic aerogels were produced after freeze-drying, which could resist combustion and exhibited thermal conductivity as low as 15 mW/m·K. Nonetheless, the required use of corrosive acids and oxidants challenges the large-scale production of graphene oxide (Lowe et al. 2016). Based on the layer-by-layer technique, cationic chitosan, anionic poly (vinyl phosphonic acid), and anionic montmorillonite clay were gradually deposited on CNF aerogel, demonstrating self-extinguishing behavior in a flame test but being limited by the complex fabrication route (Köklükaya et al. 2017). Polymerization of dopamine coupled hydrolysis of organosilicon gave the CNF aerogel self-extinguishing characteristics but at the trade-off of increased thermal conductivity (Li et al. 2017). More recently, the supercritical CO₂ drying process was employed to prepare flame-retardant composite cellulose aerogel with in situ formations of silica nanoparticles (Yuan et al. 2017). However, several concerns were proposed about the damage to the kidney and nasal mucosa from the tetraethoxysilane precursor in this study (Nakashima et al. 1994; Nakashima, 1994). Currently, the most commercially available flame retardants used in thermal insulation are fossil oil-based and chemically modified organophosphorus, organonitrogen and halogenated organic compounds (Costes et al. 2017). Although they are highly effective in suppressing flammability, their harmful impact on the environment and human health has caused a decline in their acceptance in general and led to legislative restrictions on utilization since 2004 (Anon 2014; Hale et al. 2006). Therefore, it is necessary to explore green chemistry principles to develop new environmentally friendly flame-retardant materials (Shen et al. 2008).

Zinc borate (ZB) is a widely used inorganic filler with good flame retardancy and smoke restraint capacity, known as a pollution-free flame retardant since its inert, nontoxic, and producible without secondary pollution (He et al. 2017). In terms of the thermal degradation process, ZB experiences endothermal dehydration and generate a dense and steady defensive zinc oxide (ZnO) and boron oxide (B₂O₃) layer on the surface, simultaneously releasing free water to gas for preserving the underlying substrate (Joni et al. 2010). To achieve sustainable development, a totally renewable and biodegradable bacterial cellulose (BC) aerogel was selected as the starting material to relieve the environmental pollution crisis. The amelioration of its flame retardant property was concentrated in this study, and a moderate method was designed for the non-agglomerated growth of ZB nanoparticles in the BC network. With low density and excellent flame retardancy and heat insulation, the prepared composite aerogel has the potential to apply in the realm of fire retarding and resisting as environmentally friendly material.

Materials and chemicals

Sodium tetraborate (Na₂B₄O₇•5H₂O) and zinc nitrate (Zn(NO₃)₂•6H₂O) were purchased from Aladdin Co. (Shanghai, China) and used without further purification. Bacterial cellulose (BC) hydrogels (Supporting Materials, Figure S1a) were purchased from Beijing First Power Green Technology Co., Ltd. (Beijing, China), and purified by soaking in 1% NaOH solution and throughout rinsing with distilled water into neutral. The purified BC hydrogels were sealed in distilled water at 5°C for further use. Deionized water was obtained from a Milli-Q Plus water purification system (Millipore, USA).

Preparation of BC/ZB composite aerogels

The schematic illustration of the preparation of BC/ZB composite aerogels is shown in Fig. 1. Firstly, BC hydrogel was fully immersed into Zn(NO₃)₂ solution at various concentrations for 36 h and dipped in an excess Na₂B₄O₇ solution to synthesize ZB particles with the assistance of ultrasonic treatment. Then, the resultant BC/zinc borate composite hydrogels were throughout washed with deionized water to remove the residual chemical reagents, and then lyophilized within a freeze-drier apparatus at -52 ℃ under vacuum for 48 h. The obtained aerogels were labeled as BC/ZB-1, BC/ZB-3, BC/ZB-6, and BC/ZB-10, corresponding to the different concentrations of Zn(NO₃)₂ solution (1%, 3%, 6%, and 10%, respectively). The load rate and density of different samples were calculated (Supporting Materials Table S1), indicating that the loading of ZB particles inside the BC network was saturated as the Zn²⁺ concentration reached 6%. Further increasing the concentration of Zn(NO₃)₂ solution could not facilitate the deposit of ZB particles, which could be synthesized and washed away during the cleaning process. Thereby, the BC/ZB-6 sample was chosen for the following tests and analysis, which is still light enough to be supported on leaf (Supporting Materials, Figure S1).

Characterization process

Scanning electron microscopy (SEM) images obtained by a Japan Hitachi S-8000 instrument were used to investigate the morphological property of the BC and BC/ZB-6 composite aerogels at ambient temperature. The distribution and quantitive analysis of elements were also conducted with the attached energy dispersive X-ray spectrometer (EDS). The samples for SEM observation were sputter-coated with gold using a vacuum sputter coater (Quorum Q150T ES, UK). Atomic force microscopy (AFM, MULTIMODE–8, Bruker Co., USA) was used to measure the surface roughness of the samples in the scanning area of 2.5×2.5 µm. TESPA-V2 AFM tip was used (resonant frequency 320 kHz and spring constant 42 N/m), and all the measurements were carried out in tapping mode. X-ray photoelectron spectroscopy (XPS) was conducted on a Thermo Scientific TM KαTM⁺ spectrometer, equipped with a monochromatic Al Kα X-ray source (1486.6 eV) and operated at 100 W. Samples were analyzed under vacuum (P < 10 − 8 mbar) with a pass energy of 150 eV (survey scans) or 50 eV (high-resolution scans), and the peaks were calibrated with C 1s peak at the binding-energy 284.8 eV for adventitious carbon. X-ray diffraction (XRD) experiments were conducted on the Rigaku D/MAX-2550 PC to measure the crystal structure of the samples at a voltage of 35 kV and a current of 30 mA. The scanning range was 2θ = 10–70°, and the scanning speed was 5°/min. Fourier transform infrared (FTIR) spectra of samples were recorded on a NEXUS-670 FTIR spectrometer by the pressurized potassium bromide troche method in the range between 4000 − 500 cm^− 1.

Thermal stability and flame retardancy analysis

The photothermal property of BC and BC/ZB-6 aerogels was examined by analyzing the temperature distribution of the corresponding IR images with SmartView (Fluck, Ti450, Everett, Washington, USA), recorded with a thermal imaging camera. Thermogravimetric analysis (TGA) was performed by a TAQ500 (Laboratory for Emerging Material and Technology, SC, USA) in an N₂ atmosphere from 50 to 700 ℃ with a heating rate of 10 ℃/min. The flame retardancy of samples was evaluated with an ignition test, and the quantitative analysis was performed on a microscale combustion calorimeter (MCC-2, FTT, British) according to ASTM D7309-2007. About 5 mg sample was heated from ambient temperature to 800 ℃ with a heating rate of 1 ℃/s in a stream of N₂ flowing at 80 mL/min. The generated volatile was mixed with a stream of O₂ (20 mL/min) before entering the 900 ℃ combustion furnace.

Physicochemical and morphological characterization

The structural and morphological characteristics of pure BC and BC/ZB-6 composite aerogel were investigated by SEM and AFM, and the representative images are shown in Fig. 2. The 3D porous networks consisting of BC microfibrils and microfibril bundles were clearly presented, and the sub-elementary fibril assembled with adjoining fibrils into about 100 nm wide flat and twisted ribbons as the result of cell mitosis. Meanwhile, some randomly three-way branching patterns also show in pure BC aerogel, probably ascribed to the generation of cellulose crystal sheets by van der Waals and H-bonding. Selected ribbons with a single fiber diameter of 78 and 128 nm were measured, respectively, and the average height of 49.2 nm was statistically analyzed from the AFM images. The successful loading of ZB was visually confirmed by the extensive distribution of spherical nanoparticles with an average diameter of 500 nm on the surface of fibers. Although the tightly deposited ZB particles did not change the porous microstructure of the BC network, the filling of ZB particles resulted in the separation of single fibers from fiber bundles during the in situ synthesis process. The probable explanation could be that the Zn ions are known as strong to break the H-bondings between cellulose chains and form several coordinate linkages, inserting the generated ZB particles between single fibers and also leading to the increased surface roughness to 70.4 nm. Accordingly, the average diameter of ZB nanoparticles was measured to be 400 nm and normally distributed (Supporting Materials, Figure S2), confirming by the metric data in AMF images. The elementary distribution inside the network of the BC/ZB-6 was further confirmed the homogemetic generation of ZB particles, and the corresponding contents of B, C, O, and Zn are calculated to be 25.0%, 14.9%, 50.0%, and 10.2%, respectively (Fig. 3).

XRD and FTIR analysis was applied to characterize the variations of crystal configuration and functional groups in BC after loading ZB particles (Supporting Materials, Figure S3). The presence of two typical diffraction peaks in the analyzed region of the BC spectrum, specifically at 2θ = 14.6° and 22.7° for (101) and (002) planes, respectively, are assigned to the distinct phases known as Iα and Iβ in cellulose I type of crystal structure with high uniplanar orientation (Qi et al. 2009). The α and β index are associated with the crystalline structure of these linear chains: triclinic and monoclinic, respectively (Koyama et al. 1997). Accompany with the formation and deposition of ZB particles, the surface of cellulose chains was extensively decorated with little effect on the crystal configuration of cellulose, evidenced by the remaining typical peaks at 2θ = 14.4° and 23.0°. Meanwhile, the diffraction peaks at 29.0°, 30.0°, 36.0°, and some intermittent peaks in the range of 38–68° confirm the successful synthesis of ZB particles according to the previous literature (Gonen et al. 2009), and other two typical peaks at 18.0° and 22.0° are covered by the crystalline peaks of cellulose. The possible chemical interactions between cellulose chains and ZB particles were also investigated in FTIR analysis. The characteristic absorptions of BC were assigned at 3341 cm^− 1 (-OH stretching), 2894 cm^− 1 (C-H stretching), 1200 − 1000 cm^− 1 (ring vibrations overlapped with stretching vibrations of C–OH side groups), and 899 cm^− 1 (the C-1 group frequency of ring frequency in the β-glycosidic linkage between the sugar units). Additionally, a band at 1427 cm^− 1 indicates the coexistence of crystallized and amorphous cellulose (Nelson and O’Connor 1964). The numerous ZB particles covered the cellulosic fibrils after the compound process, and several typical peaks from ZB appeared, including B₃-O symmetric stretching vibration at 1390 cm^− 1, B₄-O symmetric stretching vibration at 1194 − 1048 cm^− 1, and B₄-O asymmetric stretching vibration at 832 cm^− 1 (Gonen et al. 2009).

Thermal stability of BC/ZB composite aerogel

In view of the crucial thermal stability for the practical application of adiabatic materials, the pure BC and BC/ZB composite aerogels were thermal degraded and evaluated by TGA under an N₂ atmosphere from 50 to 700 ℃ with a heating rate of 10 ℃/min (Fig. 4a). The single-step thermal degradation was clearly observed for BC aerogel, breaking the basic glucose unit in cellulose and generating CO₂, tarry volatiles (levoglucosan and anhydrosugars), and char by concurrent depolymerization and dehydration reactions. The Tm (the temperature at the maximum rate of mass decomposition) was determined to be 354.9°C. Due to the uniform spreading of ZB particles inside BC aerogel, the composite aerogel took the shape of an unceasing network structure defensive layer with the steady augment of ZB particles. However, it is surprising to note that all BC/ZB samples underwent two-steps thermal degradation process, and the temperature for the massive weight loss at the first stage gradually shifted from about 135°C to 85°C. This result was closely related to the free water in ZB since the more and deeper deposition of ZB in the BC network, the more released water and the lower the onset temperature. Further increasing the temperature to about 350°C could lead to the dehydration of ZB, releasing the bound water and producing ZnO and B₂O₃, which could form a dense barrier on the surface of cellulosic fibrils to protect it from further ignition. However, the unsaturated coating of ZB particles inevitably resulted in the exposure and thermal degradation of bare fibrils inside the BC network at around 355°C, as samples BC/ZB-1 and BC/ZB-3. Two endothermic peaks could be recognized in the curves of derivative thermogravimetry analysis (DTA), one for the removal of bound water from BZ (312.14°C for BC/ZB-1 and 343.24°C for BC/ZB-3) and the other for the pyrolysis of cellulose (353.01°C for BC/ZB-1 and 358.28°C for BC/ZB-3), respectively. In comparison, the BC/ZB-6 sample exhibited a stable degradation rate during the whole pyrolysis, evidenced by the flat curve from DTA and the minimum weight loss (62%, Fig. 4b, Table S2) at the end of pyrolysis. Correspondingly, the weight loss from releasing bound water in the temperature zone from 85°C to 350°C was measured to be 22.9%, which is related to the loss of 7 water molecules (Zn₂B₆O₁₁•7H₂O) and near to the calculated value of 25.3%. This result indicated that hardly any BC was affected during high-temperature decomposition, demonstrating the excellent thermal stability of BC/ZB-6 sample. Further exploring the photothermal properties of the composite aerogel, an IR thermal camera was employed to record the corresponding temperature distribution and then evaluate the thermal behavior under light irradiation (Supporting Materials, Figure S4). Interestingly, the BC and BC/ZB-6 composite aerogels showed similar photothermal properties, and the surface temperatures were all steady at 4.5°C higher than the ambient temperature after 10 min light irradiation at 1 kW/m². Combining with the corresponding cooling curves of these two samples (Supporting Materials, Figure S5a), the BC/ZB-6 sample showed slightly better thermal insulation than BC from the more stable surface temperature in temperature rising and less heat loss in temperature drop. The chocolate on top of the BC/ZB-6 composite aerogel basically remained the original shape, differing from the melted one on BC after being heated on the asbestos mesh with alcohol lamp for 210s (Supporting Materials, Figure S5b). It is known that the three modes of heat transfer: conduction, convection, and radiation, in which gas convection is supposed to dominate in the heat transfer in the cellulose aerogel since the developed pores occupied most of the space in the network of BC and the radiation transfer could be ignored at ambient temperatures. Therefore, the BC itself exhibited a good property of heat resistance. The massive deposition of ZB particles inner BC decreased the pore size (as shown in Fig. 2) and the thermal conductivity because of the weakened convective intensity (Fleury et al. 2020). Meanwhile, the solid particles could facilitate the reflection and refraction of heat rays, which is hard to penetrate into the internal network, resulting in the further improved thermal stability of the composite aerogel.

Flame retardancy of BC/ZB composite aerogels

In order to comparatively investigate the performance on flame retardancy, the pure BC and BC/ZB-6 aerogels were ignited and combusted. Clearly, the pure BC aerogel was quickly ignited with rapid flame propagation and completely burned after the removal of the flame, showing the high flammability of pure cellulosic material (Fig. 5a-d). However, the BC/ZB-6 sample could hardly be ignited and combusted, and almost remained intact after the test (Fig. 5e-h), indicating that the incorporation of ZB particles could efficiently increase the flame retardancy of cellulosic material. Moreover, the variation of main elements after burning was monitored by high-resolution XPS analysis (Fig. 6 and Supporting Materials Figure S6). The peaks at 192 and 1022.3/1045.5 eV are assigned to the binding energy of B 1s and Zn 2p, indicating the existence of B₂O₃ (Köklükaya et al. 2017; Li et al. 2017) and ZnO (Jaramillo-Paez et al. 2018), respectively, and almost maintained after combustion, indicating that the dehydration process of ZB did not affect the instinct chemical attachment in Zn₂B₆O₁₁•7H₂O. Accordingly, the most bonded oxygen is also well presented at 531.9 eV (the binding energies of O 1s) (Zhu et al. 2018). Therefore, the main variation of chemical valence was carbon, whose C 1s peak could be deconvoluted into three peaks, assigning to the C-H bond (284.5 eV), C-O-H bond (286.2 eV), and C-O-C bond (287.6 eV), respectively (Giesbers et al. 2013). In comparison, the intensity of the C-O-H peak decreased while that of the C-O-C peak, in turn, increased. This phenomenon could probably be explained as the thermal degradation of the trace amount of cellulosic fibrils, which stretched out of the BC aerogel.

The microscale combustion calorimeter (MCC) was used to further quantitatively analyze the ignitability of the BC/ZB-6 composite aerogel. The heat release rate (HRR) curves (Fig. 7) and other combustion properties, including the heat release capacity (HRC), total heat release (THR), the peak of heat release rate (PHRR) and the corresponding temperature (TPHRR), are listed in Table 1. A sharp HRR peak at 352°C and the corresponding HRC value (237 J·g^− 1 k^− 1) were detected from pure BC aerogel, indicating the quick releasement of large amount of heat in a short time. On the contrary, the incorporation of ZB particles significantly decreased the intensity of HRR peak, which was slightly shifted to the lower temperature (319°C). The HRC value correspondingly dropped to 8 J·g^− 1 k^− 1, as well as the data on PHRR (from 214 W/g to 7 W/g) and THR (from 11.5 kJ/g to 1.6 kJ/g), exhibiting the excellent flame retardancy of the BC/ZB aerogel. The proposed mechanisms for enhancing thermal and flame retardant behaviors by depositing ZB particles are comparatively illustrated in Fig. 8. The dehydration of ZB particles carried lots of heat away at the beginning of combustion, lowering the surface temperature and releasing a large amount of moisture around the BC/ZB-6 sample. Without producing any toxic, flammable, or corrosive gas during the burning process (Khalili et al. 2019), the generated metallic oxides (ZnO and B₂O₃) formed a continuous and dense protective layer, not only retarding the spread of heat but also isolating the flammable fibrils within the combustion area (Li et al. 2019). It is worth mentioning that the saturated deposition of ZB particles on the surface of cellulose fibrils is critical for the flame retardancy of composite aerogel since fire is sensitive to any possible exposure of BC and spread around.

Table 1

MCC results of pure BC and BC/ZB-6 aerogels.
Samples	HRC (J/g·k)	PHRR (W/g)	THR (kJ/g)	TPHRR (℃)
BC	237	214	11.5	352
BC/ZB-6	8	7	1.6	319

Light-weight BC/ZB composite aerogel was successfully fabricated by in situ synthesis of ZB particles using BC aerogel scaffolds as templates. This facile, efficient, low-cost, and environmentally friendly process enabled the uniform distribution of flame retardants without collapsing the porous structure. The metallic oxides (ZnO and B₂O₃) were released by the dehydration of ZB, forming a protective layer on the surface of cellulosic fibrils and significantly preventing the ignition and thermal decomposition of BC. Meanwhile, The massive deposition of ZB particles inner BC further improved the thermal stability of BC by weakening convective intensity. Therefore, the prepared composite aerogel with excellent flame retardancy and thermal insulation performance exhibits great potential applications in the future of green packaging, advanced engineering, and building materials.

Ethics approval and consent to participate

The results/data/figures in this manuscript have not been published elsewhere, nor are they under consideration from any contributing authors by another publisher.

Consent for publication

All authors have revised the last version of the submitted manuscript and we approve its submission.

Availability of data and materials

All data generated or analyzed during this study are included in this published article and its supplementary information files.

Competing interests

I declare that the authors have no competing interests as defined by Springer, or other interests that might be perceived to influence the results and/or discussion reported in this paper.

Authors' contributions

ZX W: Investigation, Data curation, Formal analysis, Writing. YY E: Writing—review & editing. J L: Data curation, Formal analysis. TT D: Writing—review & editing. K W: Conceptualization, Project administration, Writing—review & editing, Funding acquisition. X Y: Writing—review & editing. JX J: Formal analysis, Supervision. M W: Writing—review & editing.

Funding

This work was financially supported by a grant from the National Natural Science Foundation of China (No. 31770622).

Acknowledgments

We thank Diana Hembree for the valuable suggestion and edition during the preparation of this paper.

Anitha A, Brabu B, John Thiruvadigal D, Gopalakrishnan C, Natarajan TS (2013) Optical, bactericidal and water repellent properties of electrospun nano composite membranes of cellulose acetate and ZnO. Carbohydr. Polym. 97: 856–863.
Anon (2004) Flame retardants: European union risk assessments update. Plastics additives & compounding 6: 26 – 29.
Bober P, Liu J, Mikkonen K, Ihalainen P. Pesonen M, Plumed-Ferrer C, Wright AV, Lindfors T, Xu CL, Latonen RM (2014) Biocomposites of nanofibrillated cellulose, polypyrrole, and silver nanoparticles with electroconductive and antimicrobial properties. Biomacromolecules 15 (10): 3655–3663.
Cai HL, Sharma SH, Liu WY, Mu W, Liu W, Zhang XD, Deng YL (2014) Aerogel microspheres from natural cellulose nanofibrils and their application as cell culture scaffold. Biomacromolecules 15 (7): 2540–2547.
Chen HB, Chiou BS, Wang YZ, Schiraldi DA (2013) Biodegradable pectin/clay aerogels. ACS Appl. Mater. Interfaces 5 (5): 1715–1721.
Chen WS, Yu HP, Li Q, Liu YX, Li J (2011) Ultralight and highly flexible aerogels with long cellulose I nanofibers. Soft Matter 7 (21): 10360–10368.
Costes L, Laoutid F, Brohez S, Dubois P (2017) Bio-based flame retardants: when nature meets fire protection. Mater. Sci. Eng. R Rep 117: 1–25.
Fleury B, Abraham E, De La cruz J, Chandrasekar V, Senyuk B, Liu QK, Cherpak V, Park S (2020) Aerogel from sustainably grown bacterial cellulose pellicle as thermally insulative film for building envelope. ACS Appl. Mater. Interfaces 12 (30): 34115–34121.
Fu FY, Li LJ, Cai J, Zhang YP, Zhou JP, Zhang LN (2015) Construction of cellulose based ZnO nanocomposite films with antibacterial properties through one-step coagulation. ACS Appl. Mater. 7 (4): 2597–2606.
Giesbers M, Marcelis ATM, Zuilhof H (2013) Simulation of XPS C1s spectra of organic monolayers by quantum chemical methods. Langmuir 29 (15): 4782–4788.
Gonen M, Balkose D, Gupta RB, Ulku S (2009) Supercritical carbon dioxide drying of methanol-zinc borate mixtures. Ind. Eng. Chem. Res. 48: 6869–6876.
Hale RC, La Guardia MJ, Harvey E, Gaylor MO, Mainor TM (2006) Brominated flame retardant concentrations and trends in abiotic media. Chemosphere 64: 181–186.
Han YY, Zhang XX, Wu XD, Lu CH (2015) Flame retardant, heat insulating cellulose aerogels from waste cotton fabrics by in situ formation of magnesium hydroxide nanoparticles in cellulose gel nanostructures. ACS Sustain. Chem. Eng. 3 (8): 1853–1859.
He CL, Huang JY, Li SH, Meng K, Zhang LY, Chen Z, Lai YK (2017) Mechanically resistant and sustainable cellulose-based composite aerogels with excellent flame retardant, sound-absorption, and superantiwetting ability for advanced engineering materials. ACS Sustain. Chem. Eng. 6 (1): 927–936.
He C, Huang J, Li S, Meng K, Zhang L, Chen Z, Lai Y (2018) Mechanically resistant and sustainable cellulose-based composite aerogels with excellent flame retardant, sound-absorption, and superantiwetting ability for advanced engineering materials. ACS Sustainable Chem. Eng. 6: 927–936.
Jaramillo-Paez C A, Navio JA, Hidalgo MC, Macias M (2018) ZnO and Pt-ZnO photocatalysts: characterization and photocatalytic activity assessing by means of three substrates. Catal. Today 313: 12–19.
Joni IM, Nishiwaki T, Okuyama K, Isoi S, Kuribayashi R (2010) Enhancement of the thermal stability and mechanical properties of a PMMA/aluminum trihydroxide composite synthesized via bead milling. Powder Technol 204 (1): 145–153.
Khalili P, Liu XL, Tshai KY, Rudd C, Yi XS, Kong I (2019) Development of fire retardancy of natural fiber composite encouraged by a synergy between zinc borate and ammonium polyphosphate. Compos. B. Eng. 159: 165–172.
Köklükaya O, Carosio F, Wågberg L (2017) Superior flame-resistant cellulose nanofibril aerogels modified with hybrid layer-by-layer coatings. ACS Appl. Mater. Interfaces 9: 29082–29092.
Koyama M, Helbert W, Imai T, Sugiyama J, Henrissat B (1997). Parallel-up structure evidences the molecular directionality during biosynthesis of bacterial cellulose. Proceedings of the National Academy of Sciences of the United States of America 94(17): 9091–9095.
Li YM, Deng C, Shi XH, Xu BR, Chen H, Wang YZ (2019) Simultaneously improved flame retardance and ceramifiable properties of polymer-based composites via the formed crystalline phase at high temperature. ACS Appl. Mater Interfaces 11 (7): 7459–7471.
Li Y, Wang B, Sui X, Xu H, Zhang L, Zhong Y, Mao Z (2017) Facile synthesis of microfibrillated cellulose/organosilicon/poly-dopamine composite sponges with flame retardant properties. Cellulose 24: 3815–3823.
Liu Y, Wang Q (2009) The investigation on the flame retardancy mechanism of nitrogen flame retardant melamine cyanurate in polyamide 6. J. Polym. Res. 16 (5): 583–589.
Lowe SE, Zhong YL (2016) Challenges of industrial-scale graphene oxide production. in Graphene oxide: fundamentals and applications, Dimiev, A. M., Eigler, S., Eds., John Wiley & Sons: West Sussex, United Kingdom, pp 410–431.
Nakashima H (1994) Time course of effects of tetraethoxysilane (TEOS) on the kidney and blood silicon concentration in mice. Arch. Toxicol. 69: 59–64.
Nakashima H, Omae K, Sakai T, Yamazaki K, Sakurai H (1994) Acute and subchronic inhalation toxicity of tetraethoxysilane (TEOS) in mice. Arch. Toxicol. 68: 277–283.
Nelson ML, O'Connor RT (1964) Relation of certain infrared bands to cellulose crystallinity and crystal latticed type. Part I. Spectra of lattice types I, II, III and of amorphous cellulose. Journal of Applied Polymer Science 8: 1325–1341.
Pan Y, Liu LX, Wang X, Song L, Hu Y (2018) Hypophosphorous acid cross-linked layer-by-layer assembly of green polyelectrolytes on polyester-cotton blend fabrics for durable flame-retardant treatment. Carbohydr. Polym. 201: 1–8.
Qi HS, Cai J, Zhang LN, Kuga S (2009) Properties of films composed of cellulose nanowhiskers and a cellulose matrix regenerated from alkali/urea solution. Biomacromolecules 10 (6): 1597–1602.
Shen KK, Kochesfahani S, Jouffret F (2008) Zinc borates as multifunctional polymer additives. Polym Adv Technol 19: 469–474.
Viggiano RP, Williams JC, Schiraldi DA, Meador MAB (2017) Effect of bulky substituents in the polymer backbone on the properties of polyimide aerogels. ACS Appl. Mater. 9 (9): 8287–8296.
Wicklein B, Kocjan A, Salazar-Alvarez G, Carosio F, Camino G, Antonietti M, Bergstrom L (2015) Thermally insulating and fire-retardant lightweight anisotropic foams based on nanocellulose and graphene oxide. Nat. Nanotechnol. 10 (3): 277–283.
Xu CL, Wei ZH, Gao HJ, Bai YJ, Liu HL, Yang HL, Lai YK, Yang L (2017) Bioinspired mechano-sensitive macroporous ceramic sponge for logical drug and cell delivery. Adv. Sci. 4 (6): No.1600410.
Yu RM, Shi YZ, Yang DZ, Liu YX, Qu J, Yu ZZ (2017) Graphene oxide/chitosan aerogel microspheres with honeycomb-cobweb and radially oriented microchannel structures for broad-spectrum and rapid adsorption of water contaminants. ACS Appl. Mater. Interfaces 9 (26): 21809–21819.
Yuan B, Zhang J, Mi Q, Yu J, Song R, Zhang J (2017) Transparent cellulose – silica composite aerogels with excellent flame retardancy via an in situ sol – gel process. ACS Sustainable Chem. Eng. 5: 11117–11123.
Zhang J, Cao YW, Feng JC, Wu PY (2012) Graphene-oxide-sheet-induced gelation of cellulose and promoted mechanical properties of composite aerogels. J. Phys. Chem. C. 116: 8063–8068.
Zhu LT, Zong L, Wu XC, Li MJ, Wang HS, You J, Li CX (2018) Shapeable fibrous aerogels of metal-organic-frameworks templated with nanocellulose for rapid and Large-Capacity Adsorption. ACS Nano 12 (5): 4462–4468.

No competing interests reported.

Appendix.docx

Download PDF

Journal Publication

published 29 Aug, 2023

Read the published version in Cellulose →

Editorial decision: Major revision
24 Feb, 2023
Reviews received at journal
13 Oct, 2022
Reviewers agreed at journal
08 Oct, 2022
Reviewers agreed at journal
05 Oct, 2022
Reviewers invited by journal
05 Oct, 2022
Editor assigned by journal
22 Sep, 2022
Submission checks completed at journal
19 Sep, 2022
First submitted to journal
16 Sep, 2022

You are reading this latest preprint version

Sustainable Bacterial Cellulose-Based Composite Aerogels with Excellent Flame Retardant and Heat Insulation

Status:

Journal Publication

Version 1

Abstract

Figures

Introduction

Materials And Methods

Results And Discussion

Conclusion

Declarations

References

Additional Declarations

Supplementary Files

Status:

Journal Publication

Version 1