Cardanol Content Research Articles

Упрочнение и стабилизация форм и размеров древесины осины и тополя карданолом

Aspen and poplar are the least required types of wood in the Russian Federation, whose stock is continually expanding. Such wood can be used as a substitute for valuable hardwood, but in this case the strength must be almost doubled while achieving stability in shape and size. Treatment with acetic anhydride, polyvinyl alcohol, polyethylene glycol, or hydrothermal care are the most common methods for maintaining the volumetric stability of the wood. Treatment with phenol- and urea-formaldehyde monomers, oligomers, and resins is typically done for strength improvement. The stabilization of the dimensional parameters is especially critical for pressed wood, which has 8 times greater swelling in water than raw wood. Cardanol was chosen as a modifier. It can be derived from cashew nutshell liquid or synthesized. The established technique for impregnating wood with cardanol includes 2–3 % acetic acid, followed by heat treatment at 140–150 °С for 6–8 hours. During this process, cardanol polymerizes with components of the lignocarbohydrate complex of the wood, which does not only improve its characteristics but also provides form and size stability in an environment with changeable humidity. A Mettler Toledo DSC 823e/700 differential scanning calorimeter was used to examine the kinetics. Heat fluxes were measured in 30 µl sealed steel crucibles that could sustain steam pressure up to 15 MPa. At a heating rate of 10 °C/min, the heat flow curve showed an exothermic peak with a maximum temperature of 150.7 °C. Aspen wood with 15 % cardanol content has a compressive strength along the fibers of 69 MPa, a volume swelling limit of 2.6 %, and a moisture absorption limit of 18 %. The ultimate water absorption and ultimate volumetric swelling of wood impregnated with cardanol are comparable to the relevant indications of the modified wood brands Accoja, Belmadur, and Thermowood. For citation: Shamaev V.A., Shishlov O.F. Hardening and Stabilization of Volumetric Properties in Aspen and Poplar Wood with Cardanol. Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 3, pp. 155–161. (In Russ.). https://doi.org/10.37482/0536-1036-2023-3-155-161

Highly toughened poly (lactic acid) blends plasticized by cardanol in presence of dicumyl peroxide

Grafting reaction between poly (lactic acid) (PLA) and cardanol was initiated by dicumyl peroxide at different compositions, and the mechanical, thermal properties were characterized. In absence of dicumyl peroxide (DCP), the PLA/cardanol blends showed a typical plastic behavior with increasing cardanol content, i.e. decrement of tensile strength, accompanied by increment of elongation at break, while the notched Izod impact strength kept low level until the cardanol content reached 20 wt%. When DCP was introduced into the blends, only 15 wt% cardanol content was needed to improve the notched Izod impact strength significantly. According to the thermal behavior testing results, the grafting of cardanol onto PLA chains might take responsibility for the further improvement of impact strength with less cardanol content.

Cardanol /SiO2 Nanocomposites for Inhibition of Formation Damage by Asphaltene Precipitation/Deposition in Light Crude Oil Reservoirs. Part II: Nanocomposite Evaluation and Coreflooding Test.

This study aims to evaluate the behavior of Cardanol/SiO2 nanocomposites in the inhibition of the asphaltene damage based on the coreflooding test at reservoir conditions. The nanocomposite design was performed in Part I (https://doi.org/10.1021/acs.energyfuels.0c01114), leading to SiO2 nanoparticles functionalized with different mass fractions of cardanol on the surface of 5 (5CSN), 7 (7CSN), and 9% (9CSN). In this part of the study, the nanocomposite/reservoir fluid interactions were evaluated through interfacial tension measurements and nanocomposite/rock surface interactions using water imbibition and contact angle measurements. Results showed that the designed nanocomposite leads to a reduction of interfacial tension of 82.6, 61.7, and 51.4% for 5CSN, 7CSN, and 9CSN regarding silica support (SN). Whereas, the reduction of the Si–OH functional groups from SiO2 nanoparticles due to the increase of the cardanol content affects the effectiveness of the wettability alteration for 7CSN and 9CSN. Nevertheless, when 5CSN is evaluated, the system is altered from an oil-wet to a mixed-wet state. Coreflooding tests at reservoir conditions were performed to evaluate the oil recovery after asphaltene damage, after damage removal and nanofluid injection, and after induction of a second asphaltene damage to check inhibition. Results show that the selected nanocomposites at a dosage of 300 mg·L–1 enhance the oil recovery in comparison with the baseline conditions via the reduction of the interfacial/surface forces at the pore scale and wettability alteration. It is worth to remark that this improvement remains after the second asphaltene damage induction, which proves the high inhibitory capacity of the designed nanocomposite for the asphaltene precipitation/deposition. Also, the use of the nanocomposites favors the oil recovery more than 50% compared to the asphaltene damage scenario.

Influence of Epoxidized Cardanol Functionality and Reactivity on Network Formation and Properties.

Cardanol is a renewable resource based on cashew nut shell liquid (CNSL), which consists of a phenol ring with a C15 long aliphatic side chain in the meta position with varying degrees of unsaturation. Cardanol glycidyl ether was chemically modified to form side-chain epoxidized cardanol glycidyl ether (SCECGE) with an average epoxy functionality of 2.45 per molecule and was cured with petroleum-based epoxy hardeners, 4-4′-methylenebis(cyclohexanamine) and diethylenetriamine, and a cardanol-based amine hardener. For comparison, cardanol-based diphenol diepoxy resin, NC514 (Cardolite), and a petroleum-based epoxy resin, diglycidyl ether of bisphenol-A (DGEBA) were also evaluated. Chemical and thermomechanical analyses showed that for SCECGE resins, incomplete cure of the secondary epoxides led to reduced cross-link density, reduced thermal stability, and reduced elongation at break when compared with difunctional resins containing only primary epoxides. However, because of functionality greater than two, amine-cured SCECGE produced a Tg very similar to that of NC514 and thus could be useful in formulating epoxy with renewable cardanol content.

An environmentally sustainable plasticizer toughened polylactide.

Cardanol (CD), derived from renewable natural cashew nutshell liquid, has been used as a new plasticizer for polylactide (PLA), to create blends which retain the environmentally friendly features of PLA. The differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA) and scanning electron microscopy (SEM) results all reveal that PLA and CD show good miscibility at low CD content. CD significantly decreased the glass transition temperature and enhanced the crystallization ability of PLA, demonstrating good plasticizing efficiency with PLA. At 10 wt% CD, ultimate elongation and impact toughness increased to 472% and 9.4 kJ m−2, respectively, which represented improvements of 31-fold and 2.6-fold over the corresponding measurements for neat PLA. The plasticization effect of CD was also demonstrated by the decreased melt complex viscosity and shear storage modulus at lower CD content for the blends when compared with neat PLA. Thus, the investigated CD presents an interesting candidate for a PLA plasticizer, meeting “double green” criteria. No cytotoxicity was found for the blends and hence they may be suitable for biomedical applications.

Preparation and properties of wooden fiberboards with phenol cardanol formaldehyde adhesives

The results of a study of wooden fiberboards, for which phenol cardanol formaldehyde resins with different cardanol content were used as binders, are shown. The influence of technological factors on the bending strength of fiberboards and their water absorption in the case of the use of such binders is shown.

UV-Curable Solid Polymer Electrolytes Based on Poly(ethylene glycol) and Cardanol Moiety for All-Solid-State Lithium Secondary Batteries

Solid polymer electrolytes based on poly(ethylene glycol) and cardanol, a renewable resource from cashew nut shell liquid, were prepared and their properties were investigated. UV-induced self-crosslinkable polymer matrix were synthesized by free radical copolymerization of poly(ethylene glycol) methyl ether methacrylate and 2-hydroxy-3-cardanylpropyl methacrylate. Solid polymer electrolytes were prepared by simple solution casting method followed by UV irradiation, which induces cross-linking reaction of cardanol moieties. The obtained electrolytes were dimensionally stable, free-standing, and thermally stable. Maximum ionic conductivities of 2.6 X 10-5 S/cm at 30 oC and 2.5 X 10-4 S/cm at 60 oC were obtained when cardanol content in the matrix polymer was 8 mol% and lithium salt doping concentration ([Li+]/[EO unit]) was 0.05. The feasibility of the prepared electrolytes to solid polymer electrolytes for lithium secondary batteries was examined by linear sweep voltammetry and galvanostatic charge-discharge cell test. Figure 1

Characterization of Environmentally Sustainable Resole Phenolic Resins Synthesized with Plant-based Bioresources

“Green” resole phenolic resins for laminating applications were synthesized, and their properties and thermal stability were determined. The plant-based cardanol and condensed tannin were used as the partial substitutes of up to 40% of the phenol in the synthesis of the phenolic resins. The resins were synthesized with different proportions of phenol (P) to cardanol (C) and with different total molar ratio to the formaldehyde (F) in the resins (1.25 to 2.0). An increased cardanol content resulted in a proportional increase in the flexibility and fracture toughness of the cured cardanol-phenol-formaldehyde (CPF) resins. Also, a direct proportionality was found between increasing cardanol content and decreased crosslink density of the CPF resins. The best results were obtained with the formulation with a P:F molar ratio equal to 1:1.25. Tannin was incorporated into the CPF resins and the fracture toughness and flexibility values of the cured Tannin-CPF resins were found to be proportional to and increasing with the tannin content. However, glass transition temperature (Tg), flexural stress, and flexural modulus values of the CPF resins decreased with the tannin content. TGA-FTIR study of the resins was carried out and the emitted gas species during the pyrolysis of the samples were identified. The thermal stability and the temperature of degradation of the cured CPF resins decreased with increasing cardanol content.

Synthesis and properties of glues for densified laminated wood based on alcohol-soluble phenol-cardanol-formaldehyde resolic resins

The effect of cardanol content on molecular weight distribution and kinetics of curing of alcohol-soluble phenol-cardanol-formaldehyde resolic oligomers aimed at replacing synthetic phenol with less toxic and renewable plant-based raw materials is studied. Densified laminated wood (DLW) samples were prepared. Their operating properties were shown to be superior to those of the currently produced DLW.

Analysis of the influence of cardanol content on the properties of phenol-cardanol-formaldehyde novolac resins

The influence of cardanol content on the molecular-weight distribution and curing kinetics of phenol-cardanol-formaldehyde novolac oligomers is investigated. It is shown that, depending on the cardanol content, the resulting oligomers can be used as components in glues and sealants of different purposes.

Study on the Nanocomposite Foam of Cardanol Phenolic Resin and Organo-Modified Montmorillonite

In this article, a series of novel phenolic resin modified with cardanol were synthesized. The influence of reaction condition and cardanol content on the structure and properties of phenolic resin was evaluated. The nanocomposite phenolic foam was then prepared by infusing the organo-modified montmorillonite (OMMT) in the synthesis step of cardanol phenolic resin to produce nanocomposite phenolic foams. These phenolic foams were characterized by FTIR, XRD, SEM and TGA. And the mechanical properties and fire performance of these nanocomposite foams were also measured. The results showed that the cardanol component could reduce the crosslink density of phenolic foam and thus improve the mechanical properties; the OMMT platelets were 3~10μm in diameter and 40~50nm in thick. These platelets can exfoliated and dispersed well in the nanocomposite due to the hydrogen-bonding between organo-modifier and phenolic matrix and improve the thermal stability, fire resistance and also the mechanical properties of nanocomposite foam.

Novel phenolic resins with improved mechanical and toughness properties

AbstractNovel phenolic type of thermoset resins were synthesized, and their mechanical and toughness properties were evaluated. Phenol Formaldehyde (PF) phenolic resins were modified to broaden their applications for modern composite structures. A first modification consisted of copolymerization of Phenol with Cardanol during the synthesis of resole phenolic (CPF) resins. The modified phenolic resins (CPF) were prepared at various molar ratios of total Phenol to Formaldehyde (F : P ratio) and with different weight ratios of Phenol to Cardanol. CPF resins with a maximum content of 40 wt % of Cardanol were synthesized and used. The CPF resins were applied as a plasticizer and toughening agent to the base PF resins. Both resins (CPF/PF) were mixed in different proportions, and their thermal and mechanical properties were then established. A full miscibility of the two resins was observed with the formation of a single‐phase system. An increase in the content of Cardanol resulted in a proportional increase of the flexural strength and fracture toughness together with a decrease of the flexural modulus of the cured CPF/PF resins. Further increased plasticizing and toughening effect was also observed by the blending of the CPF resins with propylene glycol. The higher toughness and flexibility effect of the CPF resins was obtained with a F : P molar ratio equal to 1.25 and with a Cardanol content of 40% (w/w). © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Modified PF Resins for Composite Structures with Improved Mechanical Properties

Novel composites resins for civil engineering structures were synthesised. Resol phenolic resins were modified by the copolymerization of phenol with cardanol (obtained from CNSL). The modified PF resins were synthesized at different proportions of phenol to cardanol and also of the total phenol to formaldehyde. The synthesis was carried out under alkaline conditions and with a maximum content of 40 wt.% of cardanol. The effect of the partial substitution of phenol by cardanol on the thermal and mechanical properties of the CPF resins was investigated. An increase in the content of cardanol resulted in a proportional increase in the flexibility and in the fracture toughness together with a decrease in the flexural modulus of the cured CPF resins. The higher toughening effect of replacing phenol with cardanol was obtained with the total P:F molar ratio of 1.0:1.25. Also a direct proportionality between the amount of cardanol content and the decrease in crosslink density of the resins was observed. Simultaneous TGA-FTIR studies of the resins were carried out and the emitted gases were identified. The results confirmed that the thermal stability and the temperature of degradation of the cured CPF resins decreased as the amount of cardanol content increased. Gas emissions during the pyrolysis of the CPF resins also increased.

Cardanol-based Resol Phenolics – a Comparative Study

Cardanol, a renewable agro-byproduct, can be substituted for phenol in phenol–formaldehyde resin (PF). However, resins made solely from cardanol have inferior mechanical properties. In this study, we synthesised a number of phenol–cardanol–formaldehyde (PCF), phenol–formaldehyde (PF) and cardanol–formaldehyde (CF) resins. In all these cases, the molar ratio of total phenol to formaldehyde (P:F) was maintained at 1:1.75. Subsequently, PF and CF resins were mechanically mixed in such a way as to produce phenol– formaldehyde–cardanol formaldehyde blends (PFCF) with the same total phenol to cardanol ratios as in the case of PCF resin. The mechanical, abrasive and thermal properties of the PCF and PFCF resins were studied to optimise the phenol to cardanol ratio and also for comparison of the properties of these two resins. The tensile and flexural strength decreased with incorporation of more cardanol units into the phenolic resin. However, an increase in impact strength is observed for both PCF and PFCF resins with up to 4–6 mol.% cardanol. The thermal properties of phenolic resin are negatively influenced by cardanol content. Between PCF and PFCF resin, PFCF shows better thermal stability.

Studies on the Modification of Commercial Epoxy Resin using Cardanol-based Phenolic Resins

Bisphenol A epoxy resin is blended with different phenolic novolac resins for property modification. The phenolic resins employed are (a) novolac resins derived from phenol/formaldehyde (PN) and cardanol/ formaldehyde (CDN) condensation and (b) condensation products of cardanol—phenol mixtures with formaldehyde (CPNs). Cardanol is the main constituent of cashew nut shell liquid (CNSL), a renewable resource. Epoxy resins containing 2.5—20 wt% of the above novolacs are prepared and tested for mechanical properties, water absorption, etc. Blends containing 5—10 wt% of novolacs show substantial improvement in properties. These properties show a declining trend with higher novolac loading. The stoichiometric ratio between phenolic material and formaldehyde in the novolacs is optimized (1:0.8) for maximum property enhancement. Among the novolacs studied, those prepared from cardanol—phenol mixtures of different molar ratios (CPNs) yield comparatively higher energy absorption at break and this property increases with increase in cardanol content in the modifier resin up to 40%. The property profiles of these epoxy—novolac blends imply a toughening action by novolac resins, especially phenol—cardanol—formaldehyde resins.

Effectiveness of Cardanol as Plasticizer for Silica-Filled Natural Rubber

Cardanol is the main ingredient of cashew nut shell liquid (CNSL), an agro-byproduct. Its comparative merits for plasticizing silica-filled natural rubber (NR) is the subject of this paper. Aromatic oil is the conventional plasticizer employed for such compounding requirements. The mechanical properties, ageing behavior and torque time curves during cure of NR plasticized by both these materials are compared under identical conditions. It has been established that cardanol, when used as plasticizer, gives rise to similar mechanical properties in NR vulcanizate, shorter cure times and superior ageing behavior. The study also underlines the need for optimization of cardanol content for plasticization.

Cardanol–glycols and cardanol–glycol‐based polyurethane films

The syntheses of cardanol–glycols (CGs) and CG-based polyurethane (CGPU) films have been investigated. The characterization of CGs and CGPU films were determined by IR, 1H-NMR spectra as well as a swelling test and DSC studies. The increase of molecular weight of glycols leads to a decrease of cardanol content in CGPUs and hence decreases crosslinking density of the films, which strongly affects the swelling property and glass transition temperature. The autooxidation-polymerization of CGPUs through the double bonds of the cardanol side chain, catalyzed by cobalt salt, resulting the crosslinking films was also discussed. © 1997 John Wiley & Sons, Inc. J Appl Polm Sci 65:507–510, 1997

Cardanol-glycols and cardanol-glycol-based polyurethane films

The syntheses of cardanol–glycols (CGs) and CG-based polyurethane (CGPU) films have been investigated. The characterization of CGs and CGPU films were determined by IR, 1H-NMR spectra as well as a swelling test and DSC studies. The increase of molecular weight of glycols leads to a decrease of cardanol content in CGPUs and hence decreases crosslinking density of the films, which strongly affects the swelling property and glass transition temperature. The autooxidation-polymerization of CGPUs through the double bonds of the cardanol side chain, catalyzed by cobalt salt, resulting the crosslinking films was also discussed. © 1997 John Wiley & Sons, Inc. J Appl Polm Sci 65:507–510, 1997

Cardanol-Lignin-Based Polyurethanes

Polyurethane films were prepared from the reaction of cardanol–lignins (CL) with a different cardanol/lignin ratio and toluene diisocyanate. The crosslink density, the glass transition temperature and the mechanical properties of the obtained films were also determined. The increase of cardanol content used in CL improves the flexibility as well as the tensile strength and the glass transition temperature of the polyurethane film.

Cardanol in germ and seed oils extracted from cashew nuts obtained by the oltremare process

AbstractThe presence of cardanol in cashew seed and germ oils was detected by using a combination of the thin layer chromatography (TLC) and gas liquid chroma‐tography (GLC) techniques with infrared spectro‐scopy (IR) and mass spectrometry (MS). The oils were extracted from cashew nuts obtained by the Oltremare process (heating the nuts in cashew nut shell liquid bath at 180 C for 100–120 sec). The cardanol content was about 40 mg/100 ml of germ oil and 20 mg/100 ml of seed oil. The four cardanol components were found in the following percentages: 3‐(pentadecyl)‐phenol (II), 3.0%; 3‐(8‐pentadecenyl)‐phenol (III), 55.7%;3‐(8,11‐pentadecadienyl)‐phenol (IV), 24.2%; and 3‐(8,l l,14‐pentadecatrienyl)‐phenol (V), 17.1%, respectively. Because a constant distribu‐tion of the four cardanol components was found both in the seed and in the germ oils, it was suggested that cardanol is not a natural component of germ and seed oils, but is derived from the cashew nut‐shell liquid during the processing of the nuts.