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The manufacture of polymer composites with a lower environmental footprint requires incorporation of sustainably sourced components. In addition, the incorporation of novel components should not compromise the material properties. The purpose of this paper is to demonstrate the use of a synthetic amine functional toluidine acetaldehyde condensate (AFTAC) as a modifier for fiber-reinforced epoxy composites. One of the fiber components was sourced from agricultural byproducts, and glass fiber was used as the fiber component for comparison.

The AFTAC condensate was synthesized via an acid-catalyzed reaction between o-toluidine and acetaldehyde. To demonstrate its efficacy as a toughening agent for diglycidyl ether bisphenol A resin composites and for the comparison of reinforcing materials of interest, composites were fabricated using a natural fiber (mat stick) and a synthetic glass fiber as the reinforcing material. A matched metal die technique was used to fabricate the composites. Composites were prepared and their mechanical and thermal properties were evaluated.

The inclusion of AFTAC led to an improvement in the mechanical strengths of these composites without any significant deterioration of the thermal stability. It was also observed that the fracture strengths for mat stick fiber-reinforced composites were lower than that of glass fiber-reinforced composites.

To the best of the authors’ knowledge, the use of the AFTAC modifier as well as incorporation of mat stick fibers in epoxy composites has not been demonstrated previously.

The purpose of this paper is to find a new curing agent for diglycidyl ether of bisphenol A (DGEBA) resin and to check effectiveness of this new curing agent to obtain toughness and chemical resistance of cured epoxy.

For this purpose, an investigation was carried out to synthesise, characterise and to study curing reaction of amine functional aniline acetaldehyde condensate (AFAAC) with DGEBA resin. AFAAC was first synthesised from the reaction of aniline and acetaldehyde in acid medium and characterised by FT‐IR, ¹H‐NMR spectroscopic analyses, elemental analysis, concentration of primary and secondary amine analysis. Then equimolecular mixture of AFAAC and DGEBA was subjected to curing reaction and the reaction was followed by differential scanning calorimetry (DSC) analysis. The kinetic studies of this curing reaction, mechanical properties, dynamic mechanical analysis and thermogravimetric analysis (TGA) of cured epoxy were also reported.

The DSC analysis showed the complete exotherms of effective curing reaction indicating the efficiency of AFAAC as curing agent for DGEBA resin. The kinetic studies revealed that the curing reaction was first order. Mechanical properties reflect the better fracture properties of cured matrix and TGA showed that the cured matrixes were stable up to around 238°C.

The curing agent AFAAC has been synthesised by using aniline and acetaldehyde. By changing amine and aldehyde, other curing agents could be synthesised and the curing efficiency of these for epoxy resin could also be studied.

The method for curing study of epoxy resin (DGEBA) is novel and relevant as the cured products have high‐performance applications in protective coatings, adhesives for most substrates.

The purpose of this paper is to evaluate the concentration effect of liquid amine terminated poly (ethylene glycol) benzoate (ATPEGB) modifiers and red mud waste filler on mechanical and thermal properties of cured epoxy along with the optimum result of modified epoxy.

For effective toughening, different compositions are made by adding various concentration of ATPEGB to epoxy. The concentration of 2, 5 and 10 parts per 100 parts of epoxy resin of aluminium silicate‐based pristine red mud waste is incorporated into each modified epoxy matrix. These filled modified matrixes are cured with ambient temperature curing agent triethylene tetramine and are evaluated with respect to their impact, tensile and flexural strengths. The morphology is analysed by scanning electron microscopy and dynamic mechanical analysis. The thermal stability by thermogravimetric analysis is also reported.

The modification of epoxy resin using ATPEGB and filler shows significant enhancement of mechanical strength over unmodified epoxy. The increase depends on concentration of the modifier and filler. The reason behind this is that in the initial stage of curing the ATPEGB are miscible with the epoxy and form a homogeneous solution. This good mixing promotes the chemical reaction and network formation. During the curing process, as the molecular weight increases, the component separates within the reaction medium to form a second dispersed phase.

This paper discusses only ATPEGB synthesised by using poly (ethylene glycol) (PEG) of 200, 400 and 600 and only one filler red mud waste. Besides these, by changing the molecular weight of PEG, other ATPEGB could be synthesised and the efficiency of modification of epoxy resin using these modifiers and other filler besides red mud waste could also be studied.

This paper regarding concentration effect of modifier and filler is novel and ATPEGB modified filled epoxy could be used in the fields of coating, casting, adhesives, potting and encapsulation of semiconductor devices.

The purpose of this paper is to investigate the curing efficiency of amine functional aniline furfuraldehyde condensate (AFAFFC) for diglycidyl ether of bisphenol A (DGEBA) resin to achieve toughness, chemical resistance, etc.

To study curing reaction, the curing agent AFAFFC is synthesised first from the reaction of aniline and furfuraldehyde in acid medium and characterised by Fourier transform infrared spectroscopic analysis, elemental analysis, concentration of primary and secondary amine analysis. Then, equimolecular mixture of AFAFFC and DGEBA is subjected to curing reaction and the reaction is followed by differential scanning calorimetry (DSC) analysis. The kinetic studies of this curing reaction, mechanical properties, dynamic mechanical analysis and thermogravimetric analysis (TGA) of cured epoxy are also reported.

The DSC analysis shows the complete exotherms of effective curing reaction indicating the efficiency of AFAFFC as curing agent for DGEBA resin. The kinetic studies reveal that the curing reaction is first order. Mechanical properties reflect the brittleness of cured matrix and TGA shows that the cured matrixes are stable up to around 240°C.

The curing agent AFAFFC has been synthesised by using aniline and furfuraldehyde. By changing amine and aldehyde, other curing agents could be synthesised and the curing efficiency of these for epoxy resin could also be studied.

The method for curing study of epoxy resin (DGEBA) is novel and relevant as the cured products have high performance applications in protective coatings and adhesives for most substrates.

The purpose of this paper is to evaluate the improvement of mechanical and thermal properties of cured epoxy modified with amine functional chloroaniline formaldehyde condensate (AFCFC) and to determine the optimum level of modification.

To evaluate toughening, different compositions were made by adding various concentration of AFCFC to epoxy. The impact, adhesive, tensile and flexural strengths of the modified and the unmodified epoxy were characterised by dynamic mechanical analysis. Thermogravimetric properties of modified epoxy were also reported.

The modification of epoxy resin using AFCFC showed significant enhancement of mechanical strength over unmodified epoxy. The reason behind this is that, in the initial stage of curing, the AFCFC are miscible with the epoxy and form a homogeneous solution. This homogeneity promotes the chemical reaction and network formation. During the curing process, as the molecular weight increases, the component separates within the reaction medium to form a second dispersed phase.

The toughening agent AFCFC has been synthesised by using chloroaniline and formaldehyde. By changing amine and aldehyde, other toughening agents could be synthesised and the efficiency of modification of epoxy resin using these could also be studied.

AFCFC modified epoxy could be used in the field of coating, casting, adhesives, potting and encapsulation of semiconductor devices.