Cashew Nut Shell Liquid Resin Research Articles

Development and characterization of rigid packaging material using cellulose/sugarcane bagasse and natural resins

Composites developed from cellulose and natural resins have received much attention due to their low cost and positive environmental impact. Knowledge of the mechanical and degradation characteristics of cellulose based composite boards is essential to obtain indications of the strength and degradability of the resulting rigid packaging material. The composite was prepared with sugarcane bagasse and hybrid resin (a combination of epoxy and natural resin such as dammar, pine, and cashew nut shell liquid) with the mixing ratios (Bagasse fibers: Epoxy resin: Natural resin) 1:1:1.5, 1:1:1.75, and 1:1:2 using compression moulding method. Tensile strength, young's modulus, flexural strength, soil burial weight loss, microbial degradation, and CO2 evolution was determined. Cashew nut shell liquid (CNSL) resin-incorporated composite boards in the mixing ratio of 1:1:2 gave maximum flexural strength (5.10 MPa), tensile strength (3.10 MPa), and tensile modulus (0.97 MPa). The maximum degradation in soil burial test and CO2 evolution between the boards made using natural resin was found in the composite boards incorporated with CNSL resin with a mixing ratio of 1:1:1.5 were 8.30 % and 12.8 % respectively. The maximum weight loss percentage (3.49) in microbial degradation analysis was found in the composite board made using dammar resin in the mixing ratio of 1:1:1.5.

Studies on Water Absorption Properties of Fiber- Board Prepared Using Sugarcane Bagasse with Natural Resins

A study was conducted to evaluate the effect of fiber content and incorporation of natural resin on the water absorption behavior and swelling in thickness of sugarcane bagasse (SB)-reinforced epoxy-natural resin fiber-boards. Artificial (epoxy) and natural resins (cashew nut shell liquid (CNSL) resins, black dammar and pine resins) were used as a binder. The weight proportions of fiber: epoxy + hardener: natural resin were viz., 1:1:1.50, 1:1:1.75, 1:1:2. The lowest water absorption percent value for the sample immersed for 2 h and 24 h is shown by board prepared by mixing cashew nut shell liquid resin. There was less swelling in the thickness of the fiber board made with the fiber to resin weight ratio of 1:2.75. The cashew nut shell liquid resin was found to be effective in terms of Water absorption (WA) and thickness swelling (TS). Hence, the cashew nut shell liquid resin would be an alternate source for artificial resin source with less environmental hazards.

Extraction, Characterization and Application of Cashew Nut Shell Liquid from Cashew Nut Shells

In this study, cashew nut shell liquid has been extracted from cashew nut shells using an accelerated solvent extraction technique and was employed as a precursor for the synthesis of cashew nut shell liquid resin. The extract was a dark brown viscous liquid with an average yield of 30.61±0.200%. Results of the physical analysis showed a moisture content of 4.45±0.020% and a density of 0.95±0.300 gcm-3. The percentage brix and refractive index were 76.20±0.001 and 1.47 ±0.010 respectively. Chemical characterization showed a pH of 5.65±0.003; acid value of 8.25± 0.200 mg KOH/g; ash content of 1.80±0.6%; free fatty acid of 4.12±0.400 mg KOH/g; ester value of 247.01±0.100 mg KOH/g and a saponification value of 255.26±0.800 mg KOH/g. The FTIR spectra revealed that cashew nut shell liquid is polymeric. These findings confirm that higher phenolic compounds which can be used as potential precursors in industrial applications could be obtained from agro wastes.
 Practical Applications: Cashew nut shell liquid, an extract from cashew nut shell, an agro waste has a wide range of functional products. A practical application is synthesis of a high viscous, flexible cashew nut shell liquid resin with physical properties that are consistent with literature and could also be further used in other industrial applications. Further processing of cashew nut shell for the development of value added products like resin can be a better option.

Evaluation of Mechanical Properties of Teak Wood Saw Dust – Cashew Nut Shell Liquid Resin Composites

Nowadays the use of composites is increased in various fields because of the favourable properties such as light weight, high stiffness and strength when compared to other materials. In the past few years natural fibres are being used due to their eco-friendly nature and lower costs. In this work, natural fibre composite panels are prepared using Cashew nut shell liquid (CNSL) resin as matrix and Teak wood saw dust as reinforcing material. Three set of samples have been made by varying the amount of resin by keeping the quantity of Teak wood saw dust as constant, to investigate the mechanical properties of the new composite.

Use of a Cashew Nut Shell Liquid Resin as a Potential Replacement for Phenolic Resins in the Preparation of Panels – A Review

The Cashew Nut Shell Liquid (CNSL) can be considered as a versatile raw material with wide applications in the form of surface coatings, paints and varnishes, as well as the production of polymers. Within this context, the chemical constituents of CNSL (anarcadic acid, cardanol, 2-cardol and methylcardol) become promising in the development of new materials components. Once separated, CNSL can be used in the research and development of additives, surfactants, pharmaceuticals, pesticides, polymers, resins and others. Being a byproduct, CNSL used in the preparation of new materials is characterized as a truly technological innovation.

Comparison of Cashew Nut Shell Liquid (CNS ) Resin with Polyester Resin in Composite Development

Natural resins can compete effectively with the synthetic ones in composite development. In this research, cashew nuts were picked and processed for the extraction of the resin content. The resin (natural resin) so obtained was mixed with cobalt amine (accelerator), methyl ethyl ketone peroxide (catalyst) to develop two sets of composite specimens – specimens without fibres and specimens reinforced with glass fibres. This method of sample specimen development was repeated with polyester (synthetic) resin. Compressive and tensile strength tests conducted proved that composites developed with cashew nut shell liquid (CNSL) resin were comparable to those developed with polyester resin. In the results, CNSL has an ultimate compressive strength of 55MPa compared to that of polyester resin with an ultimate strength of 68MPa. The result of tensile strength proved cashew nut shell liquid resin (with ultimate strength of 44MPa) to be better than polyester resin with 39MPa as ultimate tensile strength. This means that natural resins could be a better substitute for the synthetic ones when the required quantities of fibers (reinforcements) and fillers are used in the fibre-reinforced plastic composite developments. KEYWORDS : CNSL resins, polyester resins, composite development, strength tests

Mechanical Properties of Rice Husk Fiiled Cashew Nut Shell Liquid Resin Composites

The need to have composite materials that are renewable has lead to materials scientists researching on natural fibres. To minimize environmental pollution research into rice husk has been on for a period of time now. In this research cashew nut resin reinforced rice husk composite was fabricated at different particle sizes and different filler loading. The present study reveals that both filler loading and particle size can affect the tensile strength, young modulus, strain at failure, flexural strength, and impact strength. As the % filler content increases all particle sizes (400µm, 600µm and 800µm) shows a quadratic relationship except % elongation at failure which tends to be linear at 400µm. As particle size increases all % filler content shows quadratic relationship which tends to be linear. As particle sizes increases impact strength for 10 and 30% shows a linear equation while 20% shows a quadratic relationship which tends to be linear. In general, RH/CNSR composite could be considered as a potential source of low cost, natural fibre for composites.

Biocomposites from dwarf-green Brazilian coconut impregnated with cashew nut shell liquid resin

The dwarf-green coir fibers treated with sodium hydroxide 10% produced the best set of properties of the biocomposites generated: greater roughness and exposure of intrafibrillar cavities, providing better adhesion with the matrix, higher rigidity, increased resistance to traction and better interface properties, making them better as structural materials. The best results reported in the thermal behavior of biocomposite fibers were found in fibers treated with sodium hydroxide 10%. These showed a single stage of decomposition, which occurs at a higher temperature (300°C). It was observed that the natural fibers were more resistant to the action of the microorganisms due to the presence of more lignin and hemicellulose, while fibers treated with 5 and 10% sodium hydroxide showed different degradation degree.

Effect of Phenol-CNSL-Formaldehyde Copolymer on Thermal Ageing of SBR

Cashew nut shell liquid (CNSL) is a cheap and renewable agro by-product that consists mainly of substituted phenols. A CNSL-based resin was used in this study to modify the properties of styrene-butadiene rubber (SBR). The resin was a copolymer obtained by condensing a mixture of phenol and CNSL with hexamethylenetetramine. The effect of the resin on the ageing properties of SBR vulcanizates was studied by following the changes in tensile strength, elongation at break, modulus and tear strength. CNSL directly and CNSL-based resins with different P:F ratios were incorporated into SBR and the physical properties determined. Comparison of the properties of the aged material containing CNSL resin with those of specimens not containing the resin shows improved ageing characteristics with respect to tensile strength, modulus and tear strength.

Influence of amount and modification of resin on fade and recovery behavior of non-asbestos organic (NAO) friction materials

Phenol formaldehyde resin is one of the most important ingredients in friction materials that binds the other multiple ingredients firmly. The type and amount of resin in the friction material is very critical for structural integrity of the composite. Present work focuses on the influence of resin percentage and modification of straight phenolic resin by cashew nut shell liquid (CNSL) on fade and recovery behavior of friction composites developed in the laboratory. These composites were based on variation in amount of CNSL modified resin (10, 12.5, and 15 wt.%) keeping other ingredients same. Fade and recovery studies on these composites were done according to ECE R-90 regulation. The friction coefficient (μ) (all types viz. performance, fade, and recovery), extent of fade and recovery, increase in counterface temperature, wear and mechanical properties were significantly influenced by the variation in amount of resin. It was observed that with increase in amount of resin all types of μ decreased and extent of fade increased. Most of the mechanical properties and wear, however, improved with increase in percentage of resin. Since μ is more important for friction materials rather than wear, it was concluded that 10 wt.% CNSL resin was an optimum amount for best friction performance in severe operating conditions. The performance properties of these composites when compared with similar composites based on unmodified resin in earlier work, it was revealed that the modification of phenolic resin by CNSL deteriorated the fade and recovery performance.

Effect of Phenol-CNSL Formaldehyde Copolymer on Thermal Ageing of NBR

Cashew nut shell liquid (CNSL) is a cheap agro-by-product and renewable resource which consists mainly of substituted phenols. A CNSL based resin was used in this study to modify the aging properties of butadiene-acrylonitrile rubber (NBR). The resin was a copolymer obtained by condensing a mixture of phenol and CNSL with hexamethylene tetramine. The effect of the resin on the ageing of NBR vulcanizates was studied by following changes in tensile strength, elongation at break, modulus and tear strength. Resins with different phenol/formaldehyde ratios and CNSL/phenol ratios were incorporated into NBR and the physical properties determined. Comparison of the properties of the aged material containing the CNSL resin with those of specimens not containing the resin show improved ageing characteristics with respect to tensile strength, modulus and tear strength.

Cure characteristics of alkali catalysed cashew nut shell liquid-formaldehyde resin

Cashew nut shell liquid (CNSL) is a naturally occurring chemical monomer consisting four alkyl substituted phenols. Its phenolic nature makes it suitable for polymerisation into resins by formaldehyde using sodium hydroxide (NaOH) as a catalyst and hexamethylenetetramine (HMTA) employed as a hardener. There is intense interest in understanding the cure characteristics and properties of CNSL-based resins. In this work the DSC technique has been applied to study the change in the glass transition temperature of the oven-cured resin with and without HMTA in order to monitor the extent of cure. The glass transition temperature was found to rise when the alkaline catalysed resin was subjected to higher curing temperatures regardless of the concentration of formaldehyde used. The mode of cure of the NaOH-catalysed CNSL-formaldehyde resin has been found to be more regular with HMTA hardener. FT-IR spectroscopy has been used to study the neat CNSL and polymerised CNSL-formaldehyde resin with and without HMTA. The use of the DSC and FT-IR techniques to elucidate the extent of cure of CNSL resins is a valuable step towards the production of commercially successful CNSL-natural fibre composites.

Studies on structure and properties of CNSL novolac resins prepared with succinic acid catalyst

Cashew nut shell liquid (CNSL) was used to prepare a glass fabric laminate. Two fast curing model resins were prepared using cardanol and formaldehyde in the presence of succinic acid catalyst. The resins possess ortho-ortho and ortho-para linkages. The curing kinetics of the resins showed that the resin prepared with mole ratio 0·8 possesses good curing characteristics. The IR spectra of cured resin showed responses for high ortho linkage. A CNSL high ortho novolac resin was prepared with mole ratio 0·8. The glass fabric laminates prepared with CNSL resin showed good mechanical properties and dimensional stability. It is suggested that the candidate laminate can be used as secondary load bearing structures or panels.