CC BY
24ION CROSS-LINKED DOUBLE NETWORK GELLAN GUM GEL POLYMER ELECTROLYTE FOR
FLEXIBLE SUPERCAPASITORS
Shodmanov J.
Namangan Institute of Engineering and Technology, Namangan, Uzbekistan Assistant of the Department of
Metrology, Standardization and Quality control
Boymirzaev A.
Namangan Institute of Engineering and Technology, Namangan, Uzbekistan Doctor of Sciences, Professor
of the Department of Chemical Technology
ABSTRACT
In this work, polyvinyl alcohol matrix gellan gum a novel double-network gel polymer electrolyte created and its application in a flexible supercapacitor is reported. GPE has been soaked in Potassium hydroxide to develop electrochemical and mechanical properties. Therefore, potassium ions play two critical roles: a cross-linker and ion mobility of the samples. GPE exhibits favorable mechanical strength (tensile stress 0.81 MPa, elongation break 66.3 mm/mm) and excellent ionic conductivity 0.21 S/cm. For instance, supercapacitor fabricated GPE between two active carbon electrodes, electrochemical performance exhibits 198 F/g at 0.5A/g current density and retains above 94% after 5000 charges/discharge cycles. Additionally, the electrochemical performance of the supercapacitor was tested under different tensile bending angles (0~230°C) and low-temperatures (RT—40°C). The results suggest that the supercapacitors are highly flexible and can be widely used in energy storage electric circuits and devices.
Keywords: Gellan gum, double network, ion crosslink, gel electrolyte, freezing-thawing method, ion conductivity, flexible supercapacitor.
1. Introduction
In the 21stcentury, the rapid development of modern technologies, and the requirement for energy and energy storage materials in our society are increasing. Supercapacitors (SCs) are one of the best choices for energy conservation due to many advantages such as environment-friendly features, rapid and fast charging/discharging rate, a long-life cycle [1-3]. The basic structure consists of two electrodes and an electrolyte [4]. Among them, the electrolyte plays a critical role in the influence on the SC performance by ionic conductivity and potential range [5,6].
Most of the reports about SCs are based on liquid electrolytes [7-10] which possess high ionic conductivity but some disadvantages such as leakage, corrosion, and explosions. Therefore, many achievements have been done to replace liquid electrolytes with gel polymer electrolytes (GPE) owing to easy handling without leakage, environmental safety, low internal corrosion, flexibility in packaging etc. [11-14] - Therefore, considerable efforts are being focused on the development of new types of advanced flexible SC with GPE. Polyvinyl alcohol (PVA) has been widely used as polymer matrices for the preparation of GPE because of high conductivity, good film-forming, non-toxic, good chemical stable and inexpensive [12, 15-19].
Nowadays many research interests on flexible, stretchable and wearable energy storage devices have gained [3, 20-22]. Especially, GPEs should have enough mechanical properties like stretchability, strength, and toughness, due to the possible deformation in the use process. However, the mechanical properties of PVA GPE are still not good and there are few reports to improve them. Many methods have been achieved for hydrogel to improve its mechanical properties such as slide-ring [23], hydrophobically association [24-25], ionic cross-linking [26-27], microparticle composition [28], nanocomposite [28-30] and double
network (DN) structure [31-33]. Among them, DN hydrogels as promising soft-and-tough materials intrinsically possess extraordinary mechanical strength and toughness due to their unique contrasting network structures, strong interpenetrating network entanglement, and efficient energy dissipation. Therefore, the DN structure is considered an effective method to improve the mechanical properties of PVA GPE by authors.
Natural materials have been applied for the hydrogel [21], like alginic acid [34], cellulose [35], chi-tosan [35-37], guar gum [38], gellan gum [38-40] (GG) and etc. GG is a hydrophilic linear anionic polysaccha-ride produced from Pseudomonas elodea and is biocompatible thermal stability, non-toxic, inexpensive and good gel-forming. The most important property of our work GG can cross-link through K+ ions under low temperature without chemical cross-linking agents. For this reason, K+ ion plays two critical roles: ionic cross-linker and ion transferability. Additionally, K+ ions also can help to improve the mechanical properties of the sample. In this way, a physical crosslinking PVA-GG DN GPE can be prepared, and the outstanding mechanical properties are obtained including favourable tensile stress 0.8 MPa, elongation 66.3 mm/mm accompanied an ionic conductivity of 0.21 S/cm. Besides, the extra initiator and chemical cross-linking agent are not necessary, which makes the system is clean.
The supercapacitor fabricated as a sandwich PG GPE between two active carbon electrodes. The specific capacitance of SC is 198 F/g at 0.5A/g current density and specific capacitance above 94% after 5000 charges/discharge cycles. Moreover, the electrochemical performance of SC was tested under different bent angles (0~230°C) and low-temperatures (RT~-40°C). The results suggest that the supercapacitors are highly flexible and can be used at low temperatures performance applications and devices.
2. MATERIAL AND METHODS.
2.1. Materials and preparation of electrolyte
Chemicals used in the present work were purified before use in the laboratory. Polyvinyl alcohol (PVA 1799, molecular weight about 75000, alcoholysis: 99%, Aladin industrial corporation, China) is stirred at the 90°C degrees with 20 ml water until homogenous, then we added gellan gum (GG, Shanghai Macklin Biochemical Co. Ltd, China) and stirring again a few minutes. The maximum weight of PVA and GG are 20% of the total mass of the sample. Before pouring the mixture into glass moulds, we removed the bubbling in the sample by ultrasonic vibrator and vacuum pumping. For creating the first PVA network, the solution is kept for 20 hours at under -20 freezing in the refrigerator and thawing at the room temperature (RT) for 4 hours, this cycle repeated 5 times. After the freezing-thawing cycle, the sample is soaked in the Potassium hydroxide to demonstrate the second network (KOH, AR-90%, MW-56.11 Shanghai Macklin Biochemical Co. Ltd, China) (respectively amount 0,2,4,6,8,1 M) during 24 hours.
2.2. Preparation of electrode and assemblage of the SCs
Electrode material for supercapacitor fabrication was prepared using activated carbon (AC,80 wt. %), acetylene black (CB, 10 wt. %) and binder Poly-tetra-fluoroethylene (PTFE,10 wt. %) and all the reagents (elements) were mixed with ethanol to a form homogeneous slurry. Subsequently, the slurry was coated on the nickel foamed sheet and all samples were dried at 1000C in the vacuum oven for 24 hours and then soaked in the KOH solution 24 hours. Before preparing the su-percapacitor, the mass of the electrode was measure by electronic measurement. A flexible smart SC was assembled by all the elements together in a sandwich configuration (electrode/gel polymer electrolyte/electrode).
2.3. Characterization and measurements
The mechanical properties of the samples determined by the Universal testing machine (WSM-10kN, Changchun Intelligent Instrument Equipment Co. Ltd. China) the tensile speed 100 mm/min and the maximum load of 100 N. All electrochemical measurements of the SC and GPE were performed on a Parstat 2273, Princeton Applied Research Co., USA electrochemical workstation using asymmetric sandwich two-electrodes between GPE configuration. Impedance spectroscopy (EIS) of the samples was performed in the frequency range between 0.1 Hz and 100 kHz with a potential amplitude of 5mV. The electrochemical stability window was determined using the cyclic voltammetry (CV) method and also measured by the electrochemical workstation in the potential of -0.09 V to 0.9 V at a scan rate of 5 to 100mVs-1. The ionic conductivity was calculated according to the following equation:
o=L/ (AxRb) (1)
where, L- thickness, A - area, Rb- bulk resistance of the sample. Galvanostatic charge/discharge (GCD)
cycling was tested using a battery test instrument (CT 2001A, LAND Technology Co. Ltd., China) with different current densities in the potential range of 0.09~0.9 V. The supercapacitor specific capacitance (C, F/g) calculated from the charge/discharge curve by the following equations:
C = (IxAt) /(AVxm) (2)
Cs = 4xC (3)
where I is discharge current, At is the discharge time, AV is discharged voltage range, and m denotes the mass of the activated carbon in two electrodes. The water content could be estimated using the following equation:
Wc (%) = (Wt-Wd)/ Wt x100% (4) where: Wc is water content, Wt is the wet weight of membranes before drying, and Wd is the dry weight of membranes after drying in a vacuum oven at 60°C. The mechanical properties of the samples determined by the Universal testing machine (WSM-10kN, Changchun Intelligent Instrument Equipment Co. Ltd. China) the tensile speed 100 mm/min and the maximum load 100 N.
The GPE was analyzed by a Smart-lab X-ray dif-fractometer (XRD, Rigaku Corporation, Japan) with a scanning range of 10~80° and a scanning speed of 10°/min. The surface morphology and energy dispersive spectrometer (EDS) of the PG GPE sample investigated by SEM (FEI Quanta 250, Brock AG, German) at 15 kV. Before observation, the membrane samples are fractured in liquid nitrogen and sputtered with gold. The surface chemical composition and chemical states of the elements in GG were determined by X-ray pho-toelectron spectroscopy (XPS; Axis Ultra, Kratos Analytical LTD, England) with Al Ka radiation and low energy electrons stream as the excitation source 225 W, 15mA 15kV). Fourier transmission infrared spectra (FTIR) of the films were recorded at room temperature using a Bruker IFS-25 spectrometer at a resolution of 2 cm-1 in the range 4000-400cm-1 and the sample was pressed into a slice with KBr.
3. RESULTS AND DISCUSSION PG DN GPE is prepared via the "freezing-thawing" and "soaking" method. The first network is the PVA network and created by the freezing-thawing cycles. Such a technique produces stable hydrogels that are physically cross-linked by the presence of crystalline regions. In addition to their non-toxic nature, these freeze/thawed gels have demonstrated enhanced mechanical properties, particularly for flexible electrolyte applications. In this method, the number of cycle times is enormously important to enabling the crystallite structures and mechanical properties of the PVA. During the freezing process, the movement speed of molecules is sharply reduced, resulting in that PVA molecules approach each other and microcrystals as physical crosslinking points formed [41].
PG 10 DN GPE
Figure 1. Double network cross-link structure of PG GP
And then, the PVA segments are activated during thawing at RT leading to the growth of the crystals, which leads to the formation of a hydrogel network. Further, the network can be strengthened by repeated thawing and freezing cycles. The second network is the GG network formed during soaking in the KOH solution because GG can be cross-linked by the metal ions (K+, Na+, Ca2 and Mg2+, etc.). and
K+ is more effective among them. So, K+ ions play two important roles in this work, the first current carrier and the second crosslinker (Figure 1). Simultaneously, K+ ions also can help to improve the mechanical properties of the sample. Furthermore, the two networks of PG DN GPE are both physical networks without extra chemical crosslinking agents and initiator, reducing the residual impurity.
Figure 2. The effect of GG concentration on the sample a) stress-strain curves and b) comparison of tensile stress-strain (with 8M KOH), c) ionic conductivity and water content index.
Figure 2 shows the influence of the ratio between PVA and GG (PVA: GG= 100:0%, 95:5%, 90:10%, 85:15% and 80:20%) on the mechanical properties. The tensile strength increases along with the increase of GG content at first 0.17 MPA and reaches 0.81 MPa with GG content of 10%, and then decreases, however, it is still much higher than pure PVA GPE without GG. A similar change rule appears in the elongation at the break, which is 20 mm/mm without GG; however, improve until 66.3 mm/mm with 10% GG (Figure 2a, b). The ionic conductivity and water contents exhibit similar rising trends increasing along with GG content. The ionic conductivity and the water content vary from 0.03 to 0.21 S/cm (Figure 2c) and from 45 to 55% according to Eq. (1) and Eq. (2).
The water content of the pure PG GPE was much larger than that of the PVA hydrogel. The possible reason was that on the one hand, because GG has a certain hygroscopic property, the water content increases during soaking and more KOH solution is absorbed in the GPE; the addition of GG can hinder the crystallization of PVA and enlarge the amorphous region as proved by XRD data, thereby the number of the ion transport tunnels increase.
Figure 3 a,b shows the sample tensile stress and strain curves a remarkable increase with the increase of KOH concentration. Before KOH soaking, the stress and strain of PG-10 DN GPE are 0.17 MPa and 19 mm/mm, and then increase to 0.81 MPa and 66.3 mm/mm respectively, indicating the presence of intermolecular interactions between GG and K+ in the sample. Therefore, an increase of KOH can also positively affect the ionic conductivity of the GPE, which can be attributed to the increased current carriers, which reveal that the maximum ionic conductivity achieves 0.21 S/cm with 8M KOH (Figure 3c). However, the ionic conductivity decreases with the further increase of KOH concentration because high concentration KOH can result in the appearance of the crystalline phase of PVA and the obstruction of the ion migration in the GPE membrane.
To demonstrate the cross-link reaction and the samples after soaking, several test methods such as FTIR, XRD, XPS and SEM are applied. The recorded X-ray diffraction patterns and crystallinity of the sample with different GG contents are shown in Fig. 4. The amorphous character of GPE is important to improve both the easy
Figure 3. The effect of KOH concentration on the PG-10 GPE sample: a) stress-strain curves, (b) tensile
stress and elongation break, (c) ionic conductivity
transport of ions and water uptake which are beneficial to ionic conductivity. Typically, the pure PVA displays semi-crystalline nature and shows a clear diffraction peak at 20 = 19.8o corresponding to the (101) crystal plane [45]. However, it was observed that the intensity of the PVA characteristic peak becomes weaker in the PG DN GPEs with the increase of GG content, indicating the inhibition of the crystallinity due to the formation of hydrogen bonding and the interactions between PVA and GG. For pure PVA GPE, the reduction of the crystallinity results in the decrease of mechanical properties, however, the mechanical and electrochemical properties of PG DN GPE increase which is affirmed that soaking in Potassium salt enhances the amorphous region which is well known favourable condition for conductivity enhancement X-ray photoelectron spectroscopy (XPS) measurement was also conducted to elaborate on the chemical bonding configurations in the formed PG 3 DN GPE and PVA. Highlights on the O1s peaks are shown in the low-resolution XPS spectra of PG 10 GPE and pure PVA the curve fitting of the O1s for the different bands is shown in Figure 4b. In the O1s spectra of PG 10 GPE and pure PVA, the two deconvoluted components are observed at 531.4 and 532.1 eV, which are assigned to C-O (oxygen singly bonded to aliphatic carbon) and
C=O (oxygen doubly bonded to aromatic carbon) groups, respectively. The presence of C-O, C-OH and C=O bonds was confirmed by the O1s peaks analyses. The much smaller area of the C=O peak can be explained by this peak originating from carbonyl groups in the gellan gum structure, where the amount of GG was very low in the hydrogel, whereas the C-OH bond can be found in both PVA and GG.
FTIR spectroscopy investigation was carried out to study GG and polymer interaction with possible observational changes in the GPE due to the K+ ions containing electrolyte are shown in Figure 4. Curve a corresponds to pure GG, a significantly shows absorption peaks at wave numbers at 3273, GG powder as characterized by a peak at 3433 cm-1 of glucopyranose rings containing hydroxyl groups. 1612 cm-1 and 1411 cm-1 were asymmetric and symmetric stretching of carboxylate groups. The second spectrum (b) corresponds to KOH doped GG cross-linked. The peak at 1411 cm-1 is due to OH bending. Variations in the peaks were observed after doping, peaks of carboxylate groups shifted to 1643 cm-1 and 1442 cm-1, respectively. The last spectrum suitable PG10 DN GPE sample, in this case, we can see clearly, the new peaks corresponding to PVA.
Wavenumbers (cm"1)
Figure 4. Comparison of the samples (a) XRD (b) XPS result and (c) FTIR results
The spectrum of gellan/PVA polymers exhibited characteristic absorption bands at 3500, 3273 cm-1 and from 1611 cm-1 to 1263 cm-1 which attributed to the hydroxyl groups of glucopyranose ring of gellan and carboxyl groups of the gel-lan/PVA matrix, respectively [9], [23], [24]. A broad peak for the hydroxyl group was observed at 3273 cm-1 which represents the hydrogen bonding between hydroxyl groups of gellan and PVA.
The morphology of GG and PG-10 GPE samples were observed by SEM as shown in Figure 5.
This figure shows that the cross-linked process promotes an open structure and creates small pores. The presence of these pores increased ionic conductivity as observed and mentioned above. Pure GG exhibits smooth and thick pore walls. Compared to pure GG, PG10 GPE possesses more irregular morphology with thinner pore walls and cobweb-like fiber networks, indicating that the addition of PVA has an obvious effect on the structure.
Figure 5. A surface morphology (SEM) images of the PG10 GPE sample
The rigid GG molecular chain can change the heterogeneity of the PVA molecular chain network, and the two networks form a fine double network structure that greatly improves the mechanical properties. Due to such structure, water uptake improves and more KOH electrolyte can be absorbed and stored in GPE, which is beneficial to the ionic conductivity.
In addition to the performance mentioned above, the mechanical ability of the GPE is an essential property for the application of flexible SC.
That is a way to meet the practical demand under complex using conditions; the PG-10 sample is tested under various deformations as exhibited in Figure 6. The GPE shows outstanding mechanical properties, which can withstand high-level deformations of cutting, stretching, a 500 g weight, spiral, knotting, folding, and compression without any observable damage, indicating the potential application for flexible energy storage devices.
Figure 6. PG-10 GPE sample in various deformation tests: a)cutting, b) stretching) sustaining test under 500 g weight, d) Spiral f) knotting g) folding and h) compression.
Table 1
Comparison of mechanical and ion conductivity properties of the samples
KOH concentration Tensile stress (MPa) Tensile strain (mm) Ionic conductivity
(M) (S/cm)
0 0.17 19 0.003
2 0.23 22 0.2
4 0.28 33.9 0.21
6 0.54 58.5 0.21
8 0.81 66.3 0.21
1 0.56 49.2 0.23
According to the results listed in Table 1, the PG-10 GPE after 0.8 M KOH soaking is chosen as the electrolyte and separator for the assembly of a flexible symmetric supercapacitor with an activated carbon electrode. The electrochemical performance of the GPE all-solid-state supercapacitor with two symmetrical AC electrodes was evaluated by CV, GCD and EIS tests at room temperature.
The ionic conductivity of the prepared pure PVA GPE and PG 10 GPE is computed from the Nyquist plots shown in Fig. 8a. As we can see, PG 10 GPE exhibits significantly lower resistance (0.085 Q) than pure PVA (0.22 Q and), in coordination with the characterization results of SEM, FTIR, XPS and XRD. Figure 7b exhibits the comparison of CV curves between PG10 GPE supercapacitor and PVA GPE one at the scan rate of 10mV/s. The shapes are both almost rectangular resulting from the accumulation of the electrostatic electric charge accumulation at the electrode/electrolyte interface, indicating an
ideal electric double-layer capacitance behaviour. Besides, the CV curve area of the PG-10 GPE supercapacitor, there is only a small iRdrop, which reveals the good conductivity of the GPE. The electrode specific capacitances of SC at various current densities are evaluated by GCD and plotted in Figure 7f. It is evident that the larger than PVA GPE one indicating a higher capacitance.
Figure 7c presents the GCD curves of supercapac-itors fabricated by PVA and PG 10 GPE at a constant current of 0.5 A/g. According to the calculation through Equation 2 and Equation 3, the specific capacitance of PG10 GPE supercapacitor (198F/g) is higher than that of PVA GPE on (137 F/g), which is consistent with CV results. Figure 7d presents the CV curves of the PG10 GPE supercapacitor at various scan rates from 5 to 100mV/s, and the CV curve shape gradually deviates from the rectangle because of the diffusion-controlled ionic transport [20].
Figure 7. Comparison of PG-10 and pure PVA supercapacitors: a) Nyquist plots; b) CV curves at 10 mV/s, c) GCD curves at 0.5 A/g, d) CV curves of PG-10 GPE supercapacitor at various scan rates, e) GCD curves of PG10 GPE supercapacitor at various current densities and f) specific capacitances at various current densities
The GCD profiles of PG 10 GPE maintain a typical symmetric triangle shape with the current density varies from 0.05 A/g to 1.5 A/g (Figure. 8e), indicating the excellent electrochemical reversibility specific capacitance slowly decreases with the current density increasing. However, the specific capacitance can still achieve 185 F/g at 1.5 A/g, the remaining 94% of the highest specific capacitance (198F/g) at 0.1 A/g.
Many scientists have been investigating which performance of flexible supercapacitors under mechanical bending conditions [46]. Because this is one of the important properties and by this property, we can be used supercapacitor any complex
devices. For this reason, the electrochemical performance of the PG-10DN GPE supercapacitor was investigated by CV, GCD, and EIS tests under different bending angles from 0°C to 230°C. Figure 8a shows the Nyquist plots of five bending states from 0o to 230o, the frequency range of 100 kHz to 0.01. The result presents a concealed enlargement of resistance slightly and the graphic proves that the equivalent circuit model has not been changed under bending conditions.
Figure 8b shows the CV curves of the PG-10DN GPE supercapacitor investigated at different bending angles, at the scan rate of 10 mV/s. It can
be seen that the shapes of the CV curves under the different bending conditions were approximately rectangular and almost similar. When the bending angle increased, the area of the CV curves changed only slightly. This indicates there was no significant change for the capacitances of the PG-10GPE DN supercapacitor at different bending angles.
The GCD curves of the PG-10DN GPE super-capacitor under different bending conditions are
shown in Figure 8c. The shapes of the GCD curves recorded at different bending conditions are fairly similar. In this case, the charge/discharge time decreased significantly also when the bending angle increased from 0° to 30°. When the bending angle further increased to 230°, the charging/discharging time changed slightly. Under flat
KO Time (s.)
Figure 8. Comparison of supercapacitor under different bending angles. a) CV curves at 5 mV/s b) Nyquist
plots, and c) GCD curves at 0.1 A/g of PG 10 GPE
230o, the electrode specific capacitances was 172 F/g and 198 F/g, respectively, which are nearly equal, revealing good angle stability and ideal flexibility of the PG10 GPE supercapacitor (Equa-
tion2). All results indicate the PG-10 DNE GPE su-percapacitor is still functional under bending conditions and shows a stable electrochemical performance under the bending conditions.
Figure 9. Electrochemical performances of the supercapacitor at low temperature: a) CV curves are 5mV/rms; b) Nyquist plots; (c) GCD curves at 0.1 A/g, d) photograph of an LED-lit up by the PG-10 GPE supercapacitors.
Typically, the supercapacitors require a normal and operation working range at -10°C to +70°C. Usually, the hot temperature significantly affects the stability and thermophysical properties of electrolytes because temperature facilitates the ion transport in the gel electrolyte and resulting, influences the electrochemical performance of supercapacitors45.
For this reason, to evaluate the low-temperature performance of our PG-10 DN GPE superca-pacitor, capacitive behaviours were measured through EIS, CV, and GCD in the usable temperature range between room temperature and -40 °C (Figure 9). Despite the temperature was reduced the almost same-rectangular shape of voltammograms still can be seen. This is mainly because PG-10 DN GPEs contained good ionic conductivity also at low temperatures. The capacitance of the supercapaci-tors after some cooling cycles between room temperature and -40 °C appears to be nearly the same as the one at room temperature (Figure 9a).
GCD measurements were carried out to characterize the cycling stability of the supercapacitor at low temperatures (Figure 9c). According to this graphic, the supercapacitors have electrochemical
property, and their performance does not deteriorate even at high or low temperatures.
Significantly, the device can be used to light a red LED by supercapacitor devices connected (Figure 9d) and indicating it is suggesting realistic good applications in energy storage.
CONCLUSIONS
In summary, we developed a novel composite PVA/GG DN gel polymer electrolyte by a repeated freezing-thawing method for the flexible supercapaci-tor. The important aspect of this work that electrolyte has good mechanical properties and high ion conductivity, low-cost and non-toxic. The experimental results show that higher mechanical properties (stress-0.81 MPa, elongation break 66.3mm/mm) and ionic conductivity of 0.21 S/cm. The supercapacitor assembled PG-10 GPE with active carbon electrodes, electrochemical performance is demonstrated low resistance, high capacitance, and fast charge property. Additionally, su-percapacitor measured under different angels (0~230°) and low-temperatures (RT~ -40°C). Furthermore, when the PG 10 GPE supercapacitor is fully bent, the specific capacitance and the charge-discharge behaviours of the supercapacitor hardly change. The results suggest that the supercapacitors are highly flexible and can be used at low temperatures application and devices.
Consequently, the novel GPE supercapacitor has vast potential for practical application, such as portable and flexible electronic devices. More importantly, the results of this work have practical significance in the application of flexible devices.
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СИНТЕТИЧЕСКИЕ ВЫСОКОПОЛИМЕРНЫЕ ДИЭЛЕКТРИКИ. РЕАКТОРЫ ВЕКТОРНОЙ ЭНЕРГЕТИКИ
Власов А.В.
ООО «Альфа», г. Москва Власова В.К.
Благотворительная общественная организация «Валентина», г. Балаково
Пономарева М.В. НОУ «Fin-iks», г. Москва Власов В.В.
Вольский военный институт материального обеспечения, г. Вольск
SYNTHETIC HIGH POLYMER DIELECTRICS. VECTOR REACTORS
Vlasov A.
Alpha LLC, Moscow Vlasova V.
Charitable public organization "Valentina", Balakovo
Ponomareva M. NOU "Fin-iks", Moscow Vlasov V.
Volsk Military Institute of Material Support, Volsk
АННОТАЦИЯ
Впервые предложено рассмотрение векторной энергетики синтетических высокополимерных диэлектриков. Такой подход позволяет рассматривать синтетические высокополимерные диэлектрики с точки зрения конструкторской динамики материалов: скорости механического (электрического) воздействия, векторы Умова энергетических реакций, предельные их значения выше (ниже) которых наступает разрушение материала.
