Rocket Fuels Research Articles

Ameliorating the Methodology to Chill Rocket Fuels for Launch Vehicle

AbstractCurrent Launch vehicles of ISRO uses Earth storable propellant such as UH25/MMH and N2O4/MON3 as fuel and oxidizer respectively for their liquid engines. Chilling of these rocket fuels is necessary before loading them in Launch Vehicles to meet the liquid engine requirements so as to meet the desired net positive suction head for the turbo pumps of rocket engines (like VIKAS engines). Pressure fed engine is cooled using regenerative cooling technique. To compensate for the pressure drops in the piping when fuel flows, the chilled propellant makes it heavy in density and helps to maintain greater injection pressure. In ISRO spiral plate heat exchanger is used or chilling the propellants. The chilling activity requires around 10 to 12 hours to chill propellants from ambient to 10° C for given flow rate and effective reynolds number. Reducing this time will be very helpful in reducing the time required for overall system readiness for launch activities. Existing chilling process involves circulating propellant through one heat exchanger using a pump. The storage facility has two heat exchangers and two pumps and out of which only one heat exchanger and one pump is being used and the other act as standby. The paper aims to find possible alternate configurations using the idle heat exchanger and pump and also to study the effect of mass flow rate of propellant on chilling time. Study in this paper is done considering N2O4 propellant. A theoretical model is developed using basic heat transfer equations in MATLAB, it is evaluated by comparing the results with previous mission data. This is later applied on different configurations possible and chilling time for each configuration is calculated. The results obtained suggested that by operating two heat exchanger in parallel and one pump, time required for chilling of propellants can be reduced significantly.

Development of a non-stoichiometric equilibrium model of downdraft gasifier

ABSTRACT Mathematical modeling is an integral part of the design to necessitate lower production costs and optimized performances. Biomass gasification is an area wherein extensive research is ongoing to tap into this potentially sustainable energy source. In this paper, a mathematical model based on the minimization of the total Gibbs energy of the system is developed to analyze, predict and optimize the performance of the gasification process. The model is validated through the results published by other authors in the literature. The minimization of Gibbs free energy gives a thermodynamic equilibrium approximation of the gas composition. The modeling considered here is an extension of the chemical equilibrium analysis developed by NASA for the estimation of chemical equilibrium of combustion process of rocket fuels. The model is further extended to estimate the composition of the gas obtained by a downdraft gasification of Lantana Camera.

Clustering of paraffin-based hybrid rocket fuels combustion data

Clustering was applied to image data of hybrid rocket combustion tests for a better understanding of the complex flow phenomena. Novel techniques such as hybrid rockets that allow for cost reductions of space transport vehicles are of high importance in space flight. However, the combustion process in hybrid rocket engines is still a matter of ongoing research and not fully understood yet. Recently, combustion tests with different paraffin-based fuels have been performed at the German Aerospace Center (DLR). For a detailed analysis, the combustion process has been captured with a high-speed video camera, which leads to a huge amount of images for each test. In the end, a large data set with a total number of 30,000 images for each combustion test has to be analyzed. To catch the essential flow structures, the combustion data set was clustered with a K-means++ algorithm. Since the algorithm might converge to local optimal solutions, expensive repetitions have been performed to ensure that a global solution is found in the end. Furthermore, a detailed analysis was performed to find an adequate clustering algorithm in the first place and to estimate the number of relevant clusters K in each experiment. As a result, valuable insights into the different combustion phases were obtained and a comparison of the quality of the combustion flame in the different tests could be made. In particular, depending on the fuel formulation and oxidizer mass flow, differences in the transients and flame brightness were found.

Usage of Colloidal Gunpowder Released from Utilized Ammunition in the Mining Industry

Disposal of obsolete munitions is a permanent process, during which colloidal gunpowder are liberated and accumulated. Especially large quantities of such materials were accumulated in the countries ofthe former Soviet Union, including Georgia. Warehousing and storage of such materials and/or direct application may cause a serious threat/risks in terms of ecological and unauthorized use. Therefore, today’s colloidal gunpowder is mainly stored and the expenses of their storage permanently increase, in addition, there is a permanent threat of their unauthorized use, because they belong to the class of explosives. The long-term storage of the overdue gun powders and rocket fuels contains self-blasting risks. So, this problem is urgent at the local and global levels. Traditional ways of problem solution area simple creation of new explosive materials on the base ofthe application of ingredients possessing better properties. In distinct from the traditional methods, the essence of the offered works is a creation of new type industrial explosive compounds and application of fuel removed from utilized missiles/shells of military designation in the role of components of explosive materials. A number of hints have been identified in the process of studying the exploitation of industrial explosives on the base of gunpowder and solid rocket fuel. They have created a prerequisite that the cartridges made on the basis of colloidal gunpowder can be initiated using the malware. This method of initiation allows us to a gradual increase of the gas pressure in the chamber of the critical size at which the pressure of the gas will break through the impact of the shaft and thus the breaking of the rock. In the process of research, explosives characteristics of pyroxylene and ballistic fuel mixtures have been studied. It was established that the granulomatrium composition of the mixture is significantly influenced by these characteristics. For example, if the diameter of the granules varies between 3-20 mm, the reaction of the collapse of the mixture is carried out steadily with blast mode, without switching to the detonation. If 10% or more granules in the explosive mixture are smaller than 1 mm, the combustion process can be transferred to the detonation.

The combination of mirtazapine plus venlafaxine reduces immobility in the forced swim test and does not inhibit female sexual behavior

IntroductionDepression is a psychiatric disorder with higher incidence in women. Among the most common and less investigated adverse effects of antidepressants are the female sexual dysfunctions. Up to one third of the patients fail to respond to antidepressants; therefore, more treatment alternatives are necessary. The combination of mirtazapine plus venlafaxine, known as “California Rocket Fuel” has shown to be an option for treatment-resistant depression. However, there are no reports of the effects of this combination in animal models and its action on female sexual behavior is unknown. AimTo analyze the effect of mirtazapine and venlafaxine alone or combined –given at doses with actions on the forced swim test- on female rat sexual behavior. MethodsMirtazapine (10, 20 or 40 mg/kg) and venlafaxine (15, 30 or 60 mg/kg) or their combinations (2.5/3.75, 5/7.5, 10/15 and 20/30 mg/kg mirtazapine and venlafaxine, respectively) were injected to sexually receptive female rats. We evaluated their effect on the forced swim test (FST). The doses that reduced immobility were tested on proceptivity and receptivity. ResultsMirtazapine (40 mg/kg) and venlafaxine (60 mg/kg), administered alone, or combined (mirtazapine, 5, 10 and 20 mg/kg plus venlafaxine, 7.5, 15 and 30 mg/kg) reduced immobility, but affected motor activity. However, the reduced locomotion after the lowest combination (5/7.5 mg/kg) was smaller. Mirtazapine at 40 mg/kg reduced proceptivity and receptivity, while 60 mg/kg venlafaxine only decreased proceptivity. The combination of 5/7.5 mg/kg mirtazapine and venlafaxine did not affect female sexual behavior. ConclusionsMirtazapine and venlafaxine exerted an effect in the FST, which was also evident when sub-effective doses of both antidepressants were combined. This combination also lacked adverse effects on female sexual behavior. The results suggest that “California Rocket Fuel” could be an effective antidepressant therapy with no adverse sexual effects in women.

Preparation and Characterization of Cellulose/RDX Composite Aerogel Spheres

AbstractAs a high‐energy explosive, 1,3,5‐Trinitroperhydro‐1,3,5‐triazine (RDX) has been widely used in military and civilian applications such as explosives, rocket fuels and gun propellants due to its good comprehensive properties. However, at present, the application of RDX has been encumbered by its high sensitivity and crystal defects. Herein, inspired by the unique structure and eco‐friendliness of cellulose aerogel, for the first time, cellulose aerogel was introduced into RDX to prepare cellulose/RDX composite aerogel spheres by the solution impregnation method. The cellulose/RDX composite aerogel spheres were characterized by scanning electron microscopy (SEM), elemental analysis, thermogravimetric and differential scanning calorimetry (TG‐DSC), X‐ray diffractometer (XRD), and a vertical impact sensitivity tester. The material detonation speed was calculated using EXPLO5. The results showed that the surface of cellulose/RDX composite aerogel spheres was smooth, and the internal three‐dimensional cross‐linked void of the cellulose aerogel spheres was well filled with RDX particles. Compared with RDX raw materials, the particle size of RDX in the cellulose/RDX composite aerogel spheres was greatly reduced. The N content in the cellulose/RDX composite aerogel spheres was as high as 32.24 %. Thermal analysis results showed that the activation energy of cellulose/RDX composite aerogel spheres increased by 31.28 KJ/mol. The crystal structure of RDX in the cellulose/RDX composite aerogel spheres remained unchanged. Moreover, the impact sensitivity H50 of the cellulose/RDX composite aerogel spheres increased by more than 65 cm.

ВЛИЯНИЕ БЕТА-ОБЛУЧЕНИЯ НА ПАРАМЕТРЫ АКТИВНОСТИ МИКРОПОРОШКОВ АЛЮМИНИЯ

Актуальность. Микропорошки алюминия являются сырьем для многих отраслей промышленности: порошковой металлургии, самораспространяющегося высокотемпературного синтеза новых материалов, водородной энергетики, пиротехники и ракетных топлив. Улучшение характеристик порошков алюминия способствует повышению их качества. Известные способы активирования порошков алюминия путем введения в состав алюминия добавок редкоземельных элементов, соединений ванадия, кремния, бора и других элементов приводит к загрязнению алюминия примесями. Облучение микропорошков β-частицами с энергией менее 8 МэВ не приводит к наведенной радиоактивности и в то же время активирует микропорошки алюминия. Цель: получение и объяснение экспериментальных данных по изменению параметров активности микропорошков алюминия после их облучения в зависимости от дозы β-облучения. Объекты: микропорошки алюминия АСД-6, АСД-6М, АСД-8, АСД-10, полученные распылением расплава алюминия. Методы: дифференциальный термический анализ, рентгенофазовый анализ, методика облучения микропорошков алюминия β-излучением, методика расчета параметров активности порошков алюминия. Результаты. Получены количественные показатели реакционной способности микропорошков алюминия АСД-6, АСД-6M, АСД-8 и АСД-10 до и после облучения β-излучением ускорителя ЭЛУ-4 с энергией 4 МэВ, т. е. энергией существенно ниже порога фотоядерных реакций, приводящих к наведенной активности. Дозы облучения образцов порошков составляли 1, 2, 4 Мрад. После β-облучения температура начала окисления снизилась максимально на 205 °С; максимальная скорость окисления возросла на 0,19 мг/мин (106 %); степень окисленности микропорошка АСД-6М повысилась на 18,9 %, а микропорошка АСД-10 минимально понизилась на 12,3 %; удельный тепловой эффект окисления после всех доз β-облучения увеличился максимально для АСД-10 на 188,6 кДж/моль. Запасание энергии микропорошками после β-облучения связано с формированием двойного электрического слоя в частицах алюминия.

Small-Scale Static Fire Tests of 3D Printing Hybrid Rocket Fuel Grains Produced from Different Materials

The last decade has seen an almost exponential increase in the number of rocket launches for sounding missions or for delivering payloads into low Earth orbits. The emergence of new technologies like rapid prototyping, including 3D printing, is changing the approach to rocket motor design. This project conducted a series of small-scale static fire tests of fused deposition manufacturing hybrid rocket motors that were designed to explore the performance of a variety of commonly available fused deposition manufacturing materials. These materials included acrylonitrile butadiene styrene, acrylonitrile styrene acrylate, polylactic acid (PLA), polypropylene, polyethylene terephthalate glycol, Nylon, and AL (PLA with aluminum particles). To test the performance of small-scale fuel grains, a modular apparatus with a range of sensors fitted to it was designed and manufactured. The small-scale testing performed static burns on two fuel grains of each material with initial dimensions of 100 mm long and 20 mm in diameter with a 6 mm straight circular combustion port. The focus of this study was mainly on the regression rates of each material of fuel grains. Acrylonitrile styrene acrylate and Nylon showed the highest regression rates, while the polyethylene terephthalate glycol regression rates were relatively poor. Also, the acrylonitrile butadiene styrene and acrylonitrile styrene acrylate demonstrating relatively high regression rates when compared to existing hybrid fuels like hydroxyl-terminated polybutadiene.

Radiation Heating Effects on Oxidizer-to-Fuel Ratio of Additively Manufactured Hybrid Rocket Fuels

Recently, multiple authors have investigated the use of additive manufacturing for precision fabrication of hybrid rocket fuels. Extensive regression rate data for 3-D printed motors with thrust levels from 5 to 900 N, using both thermoset and thermoplastic feed-stock materials, have been collected. A class of printed thermoplastics based on acrylonitrile-butadiene-styrene was discovered to present unique burn characteristics not been previously observed with many legacy hybrid rocket-fuel materials. These printed thermoplastics are shown to produce fuel regression rates that strongly correlate to motor diameter, with smaller motors tending to burn strongly fuel rich with time. This burn behavior contrasts with the known burn behaviors of most thermoset hybrid fuels whose regression rates are only weakly dependent on motor size. Nearly all thermoset hybrid fuels tend toward a lean oxidizer-to-fuel ratio as burn lifetime progresses. To describe the anomalous behavior of 3-D printed thermoplastics, an extension to the classical Marxman regression rate model was developed to account for radiant heat transfer to the material surface. The model extension is empirically verified in this report and demonstrates that observed anomalous behaviors of certain 3-D printed thermoplastics result from dominant radiant heat-transfer mechanisms that are less significant for traditional hybrid fuel materials.

Numerical Study on the Solid Fuel Rocket Scramjet Combustor with Cavity

Scramjet based on solid propellant is a good supplement for the power device of future hypersonic vehicles. A new scramjet combustor configuration using solid fuel, namely, the solid fuel rocket scramjet (SFRSCRJ) combustor is proposed. The numerical study was conducted to simulate a flight environment of Mach 6 at a 25 km altitude. Three-dimensional Reynolds-averaged Navier–Stokes equations coupled with shear stress transport (SST) k − ω turbulence model are used to analyze the effects of the cavity and its position on the combustor. The feasibility of the SFRSCRJ combustor with cavity is demonstrated based on the validation of the numerical method. Results show that the scramjet combustor configuration with a backward-facing step can resist high pressure generated by the combustion in the supersonic combustor. The total combustion efficiency of the SFRSCRJ combustor mainly depends on the combustion of particles in the fuel-rich gas. A proper combustion organization can promote particle combustion and improve the total combustion efficiency. Among the four configurations considered, the combustion efficiency of the mid-cavity configuration is the highest, up to about 70%. Therefore, the cavity can effectively increase the combustion efficiency of the SFRSCRJ combustor.

Designing, Modeling and Simulation of Solid Fuel Rocket ALP-01

Bu çalışmada katı yakıtlı alçak irtifa roketi ALP-01’in CAD tasarımı yapılmıştır. 1500 metre irtifa için roket boyutları; seçilen motor için optimize edilmiştir. Burun konisi geometrisi olarak Parabolik tip tercih edilmiş ve uzunluğu 35cm olarak hesaplanmıştır. Burun konisi ve shoulder kısmı için 3D yazıcıda kalıp hazırlanıp cam elyaf malzeme ile elle yatırma yöntemiyle bu kısımlar üretilecektir. Roketimizde iki farklı kurtarma mekanizması kullanılmıştır. Burun konisi, faydalı yük, faydalı yükün paraşütü ve roketin birinci paraşütünün roketten ayrılması için CO2 tüp ile fırlatma mekanizması tasarlanmıştır. Faydalı yükün üzerinde telemetri sistemi olan bir uçuş bilgisayarı bulunmaktadır. Bu bilgisayar yer istasyonuna konum, yükseklik, sıcaklık, nem bilgilerini anlık olarak iletmektedir. Roketimizin birbirinden ayrı iniş yapan bütün parçalarında GPS ve telemetri sistemi bulunmaktadır. Gövde üretimi için İskenderun Teknik Üniversitesi Makine Mühendisliği Bölümü mekanik laboratuvarı kompozit atölyesinde vakum infüzyon yöntemi ile silindirik kesite sahip kompozit parça üretim denemesi yapılmıştır. Kanatçık geometrisi olarak Openrocket simülasyonları sonucunda delta tipi kanatçık uygun görülmüştür. Ayrıca tasarımı yapılıp üretilmesi planlanan ALP-01 katı yakıtlı roket ile Teknofest 2019 roket yarışmasına katılınması planlanmaktadır. Çalışma aşamalarında, ikisi statik test olmak üzere dört kez katı yakıtlı roket motoru denemesi yapılmıştır. Denemelerde kullanılan yakıt karışımı (KNO3 Sükroz/Dekstroz) Makine Mühendisliği bölümü mekanik laboratuvarı kompozit atölyesinde bulunan hassas terazi, ayarlı ocak, hidrolik pres vb. ekipmanlar kullanılarak hazırlanmıştır.

SANITARY-HYGIENIC CHARACTERISTICS OF THE AREA OF POSITIONING FOR THE DISPOSAL OF ROCKET TECHNICS

There was executed the sanitary-hygienic assessment of residential areas in the zone of possible impact of industrial activity of the Center for the elimination of Intercontinental ballistic missiles affiliated to the Federal State Unitary Enterprise “Center for Operation of Ground-Based Space Infrastructure Facilities” located in the Nizhny Novgorod region. There were performed full-scale studies of air samples, water reservoirs and sources of drinking water, the soil on the content of components of liquid rocket fuels and their degradation products. Studies have shown full-time work enterprises not to be accompanied by the emission of unsymmetrical dimethyl hydrazine, Tetramethyl-2-tetrazene, NDMA into the environment. In samples of water from open stagnant water bodies there was detected both dimethylamine in concentrations exceeding MPC by 1.1 - 1.3 times, and formaldehyde in the concentration below the MAC. All soil samples also contain FA and DMA in concentrations significantly lower than the MPC. As, Be, Cd, Pb in drinking water was not detected within the sensitivity of the method, Ni content, Zn, Mg, Mn, Al does not exceed hygienic standards. Fe content in the water of centralized water supply amounted to 1.5 MAC.

Development of elementorganic chemistry in Belarus: historical flashback, modern status and perspectives (To the 100th anniversary of the birth of Yu. A. Ol’dekop)

The development of organometallic chemistry of metallocenes, in particular, the chemistry of organic derivatives of iron, manganese, titanium and niobium, is explained by their diverse catalytic activity with respect to polymerization reactions, isomerization and hydrogenation of olefins, cyclotrimerization of acetylene hydrocarbons, fixation of molecular nitrogen under mild conditions and many other processes, using these compounds as additives to fuels and high-temperature lubrication oils, vulcanization accelerators of rubbers constituting lacos and water-repellent impregnation, anti-knock agents, driers, fungicides, etc. Of particular interest are the synthetic methods and chemical transformations of titanocene and niobocene derivatives containing the metal-carbon σ -bond. Most of the titanium-c-derivatives have low thermal stability, and the niobocene derivatives are extremely sensitive to the action of air oxygen, which makes it difficult to study their chemical transformations. Carborane derivatives are used for the preparation of various types of polymers used in solid rocket fuels and as heat-resistant coatings. They are also used as agents in boroneutron capture therapy of oncological diseases. This review presents a brief historical flashback, the current state and further development of the work carried out in the laboratory of organoelement compounds, which began and was supervised by Yu. A. Ol’dekop, covering the period from 1971 to 2018. References include 80 references.

A Shock-Tube Autoignition Study of Jet, Rocket, and Diesel Fuels

Ignition delay times were measured for gas-phase jet fuel (Jet-A), rocket propellant (RP-1), and diesel fuel (DF-2) in a heated, high-pressure shock tube. The measurements were performed behind ref...

EXPERIMENTAL EVALUATION OF CHRONIC ORAL TOXICITY AND LONG-TERM EFFECTS OF SOLID ROCKET FUELS COMPONENT

The chronic oral toxicity and long-term effects of the basic lead-nickel salt of phthalic acid have been investigated by long-term oral ingestion of white outbred rats. The compound at doses of 1.0 mg/kg; 0.3 mg/kg and 0.1 mg/kg have changed the physiological, behavioral, hematological, biochemical, immunological parameters, as well as the relative weight of internal organs of animals in the six months experiments. The threshold of chronic oral toxicity of the substance is set at 0.1 mg / kg.The study of long-term effects revealed the absence of its mutagenic activity both at the gene (Ames test) and chromosomal (dominant lethal method) levels. In addition, the analyzed compound did not adversely affect the reproductive function of male rats. When entering the body of females during gestation, the toxicant did not reveal embryo-lethal and teratogenic properties.However, chronic administration of the compound into the body of non-pregnant animals at a dose of 1.0 mg/kg contributed to a significant decrease relative to the control of the mass and disk diameter of the placenta, which indirectly indicated the functional inferiority of the organ. Therefore, the considered level of the substance is defined as a threshold for gonadotoxic effect.The obtained data are taken into account in developing of hygienic standard of the estimated component of solid rocket fuels in water reservoirs.

Topology Optimization of Solid Rocket Fuel

This paper investigates possible improvements in the combustion properties of multicomponent solid propellants through the application of topology optimization methods to representative volume element (RVE) of HMX-aluminum fuel. Design objectives for the material include increased thermal conductivity and reduced amounts of induced strains under thermal loads. The targeted increases in thermal conductivity generate designs that increase burn propagation rates, whereas the reductions in structural compliance minimize relative displacements within the design cell. Novel domain-filter treatments are also developed to better control the boundary effects on the resulting designs. A family of wire-like solutions is found to provide optimal combustion and structural properties. Burn performance estimates showed 52 and 33% improvements in burn propagation speeds relative to previous designs at, respectively, 20 and 200 atm.

Energetic Potential of Some Hypothetical Derivatives of Tetrazole as Components of Composite Rocket Fuel

Energetic Potential of Some Hypothetical Derivatives of Tetrazole as Components of Composite Rocket Fuel

Mechanical Characterization of Paraffin-Based Hybrid Rocket Fuels

Abstract The present work focuses on determination of the mechanical properties of paraffin-based hybrid rocket fuels. The tensile tests were performed to evaluate the ultimate tensile strength, elastic modulus and percentage elongation at break. Three classes of paraffin-based fuels such as Paraffin/Polyethylene (P/PE), Paraffin/Polyethylene/Boron (P/PE/B) and Paraffin/Polyethylene/Aluminum (P/PE/Al) were prepared with and without Stearic acid (SA). The tensile tests were performed as per ASTM standard. The paraffin sample was used as the reference. The ultimate tensile strength of the P/PE formulation increased from 14% to 39%with the increase of PE loading from 5wt.% to 15wt.% and the elastic modulus was found to increase from 114.36 MPa to 129.27 MPa. Furthermore, the addition of SA also contributed to the increase of tensile strength and elastic modulus for P/PE formulations. For the P/PE formulation, the addition of B enhanced the tensile strength from 32.7% to 47.13% with the loading of B content increased from 5wt.% to 25wt.%. The paper discusses about the effect of additives on the formulation and the optimal loading ratio without compromising on the regression factor.

Simulation of an Antimatter Beam Core Engine for Space Travel

An exciting prospect is the use of antimatter as a fuel source due to its ability to convert mass energy to kinetic energy. Upon annihilation of antimatter with matter, tremendous amounts of energy are carried away by charged and neutral particles. By redirecting the charged particles through an exhaust using a non-uniform magnetic field, an impulse can be generated capable of supplying thrust to an engine. Using the Geant 4 simulation toolkit developed by CERN, we simulate this process using a beam core engine design. By analyzing charged pions that result from antiproton-proton annihilation, we optimize the engine parameters and derive a specific impulse for antiproton fuel as used in the beam core configuration. A specific impulse of (2.49 ± 0.08) × 106 s was determined. This value is significantly higher than specific impulses of current chemical rocket fuels which range from 240 - 400 s.

Furfuryl Alcohol a Versatile, Eco-Sustainable Compound in Perspective

Renewable agricultural biomass derived chemicals, their modifications and uses have seen multiplicity in numerous applications and important processes with major impacts on the pursuit for eco-sustainability. Such applications range include the energy sector, chemistry, pharmacy, the textile industry, paints and coatings, plastic industry, to name but a few. This field of lignocellulosic derived chemicals interconnects several scientific disciplines ranging from agriculture, biochemistry, engineering, environmental sciences, forestry, pharmacy, medicine, etc. hence making it difficult to have a single expert view on these complicated interactions. Therefore, the idea to create a focused review, specifically, on FA (an important furanic compound) is the main objective of this article. FA and its resultant derivatives exhibits an array of capabilities and fascinating properties in various fields of applications. As a compound or with co-reactants, it finds interesting applications as base and/or intermediate chemical compound, hypergolic rocket fuels, in flame resistant composites and coatings used in aerospace, auto, and the built environment; it also finds application as mortars, cementitious grouts, impregnating materials, and sealants due to its exceptional resistance to common corrosive chemicals such as acids, alkalis and other solvents when it is cross-linked. Coupled with its environmental and economic benefits FA has proved to be a remarkable eco-sustainable bio-derived compound.