Search results

This paper aims to evaluate the concentration effect of red mud waste filler on mechanical and thermal properties of amine functional aniline furfuraldehyde condensate (AFAFFC) modified epoxy composite along with the optimum result of modified epoxy.

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

The modification of epoxy resin using AFAFFC and filler showed significant enhancement of mechanical strength over unmodified epoxy. The increase depends on the concentration of the modifier and filler. The reason behind this is that in the initial stage of curing, the AFAFFC 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 with in the reaction medium to form a second dispersed phase.

The present paper discussed the effect of only one type of modifier, i.e. AFAFFC, and one filler, i.e. red mud waste filler effect. Besides these by changing the amine and aldehyde, other modifiers could be synthesised and the efficiency of modification of epoxy resin using these modifiers and other filler besides red mud waste such as paddy husk, bamboo dust, etc., could also be studied.

The present study regarding the concentration effect of modifier and filler was novel, and AFAFFC modified filled epoxy could be used in the field of coating, casting, adhesives, potting and encapsulation of semiconductor devices.

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.

To evaluate the improvement of mechanical and thermal properties of cured epoxy modified with amine functional aniline formaldehyde condensate (AFAFC) along with the optimum result of modified epoxy.

For effective toughening, different compositions were made by adding various concentration of AFAFC to epoxy. The impact, adhesive, tensile and flexural strengths of the modified and the unmodified epoxy were characterized by dynamic mechanical analysis. Thermo gravimetric of modified epoxy was also reported.

The modification of epoxy resin using AFAFC showed significant enhancement of mechanical strength over unmodified epoxy. The reason behind this is that in the initial stage of cure the AFAFC 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 with in the reaction medium to form a second dispersed phase.

The toughening agent AFAFC have been synthesized by using aniline and formaldehyde. Besides this, by changing the amine and aldehyde, another toughening agent could be synthesized and the efficiency of modification of epoxy resin using these could also be studied.

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

In order to study its cure response and to understand its kinetic behaviour, this paper seeks to examine how a multifunctional epoxy resin, N,4‐bis(4‐(bis(2‐oxiranylmethyl)amino)‐2‐chlorobenzyl)‐3‐chloro‐N‐(2‐oxiranylmethyl)benzenamine (BCCOMB), synthesised from amine functional chloroaniline formaldehyde condensate (AFCFC) and epichlorohydrine, is cured with AFCFC as curing agent.

For effective curing, AFCFC (12.5 phr, part per 100 resin) was added to BCCOMB resin and mixed thoroughly for 15 minutes. The clear viscous solution was then subjected to DSC analyses for kinetics study of the curing reaction.

The AFCFC was successfully utilised as curing agents for BCCOMB as the DSC curves show complete curing exotherm. The presence of oxirane group in the BCCOMB was able to react with active hydrogen atoms of amine. This led to conversion of liquid monomers of thermoset resin into three‐dimensional network.

In the present discussion, the curing study of BCCOMB had been done using AFCFC as a curing agent. However, other curing agents, synthesised from other amine and aldehyde, could also be used to see whether they would be effective for curing study of BCCOMB.

The method for curing study of multifunctional epoxy resin (BCCOMB) was novel and the cured epoxy network could find numerous applications as surface coating and adhesive on to an intricate structure.

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 evaluate the mechanical properties of glass fibre reinforced epoxy composites modified with amine‐terminated poly (ethylene glycol) benzoate (ATPEGB) along with their thermal stability.

ATPEGB prepared from poly (ethylene glycol) (PEG) of different molecular weights (200, 400, 600, 4,000 and 20,000) were used as modifiers for glass fibre epoxy composite here. For toughening, 12.5 parts per hundred grams (phr) of epoxy resin of each ATPEGB was added to epoxy and pre‐reacted with it. The impact, tensile and flexural strengths of modified and unmodified composite were characterised and compared for each ATPEGB.

Modified resin displayed a significant improvement in fracture toughness with glass fibre over unmodified epoxy. The modification caused the formation of oligomer domains having relatively round shapes in the matrix. These oligomer domains led to improved strength and toughness due mainly to the “rubber toughening” effect in the brittle epoxy matrix. The optimum results were obtained for composite modified with ATPEGB‐2 prepared from PEG of molecular weight 400.

In the present context, only 12.5 phr concentration of each ATPEGB was used to modify composite and the composites were made sing three layers of glass fibre. Besides, modification could also be done using other concentrations and more layers of glass fibre could also be used to make composite.

The method for enhancing toughness of epoxy glass fibre composite was novel and finds numerous applications as surface coatings, casting and adhesive onto an intricate structure, etc.

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.

To evaluate the efficiency of modifying epoxy resin using amine terminated poly(ethylene glycol) benzoate (ATPEGB) for improved toughness and to optimise the results of such a modification.

For effective toughening, various compositions were made by incorporating different concentrations of ATPEGB. The impact and adhesive strengths of the unmodified and modified epoxy networks were characterised.

The modification of epoxy resin using ATPEGB showed significant enhancement of impact and adhesive strengths over the unmodified one. The modification caused a chemical linkage between ATPEGB and resin which led not only to a phase separation but also to ensuring the intrinsically strong chemical bonds across the ATPEGB phase/resin matrix interface, which was the main cause to the improved impact and adhesive strengths. The optimum results were obtained at 12.5 phr (parts per hundred parts of epoxy resin) of modifier.

The modifier, ATPEGB, used in the present context was synthesised from poly(ethylene glycol) (PEG) of molecular weight 600. Besides, it could be synthesised from PEG of molecular weight 200, 400, 4,000, 20,000 etc. In addition, the efficiency of modification of epoxy resin using these could also be studied.

The method developed provided a simple and practical solution to improving the toughness of cured epoxy.

The method for enhanced toughness of cured epoxy was novel and could find numerous applications in surface coating and adhesive.

To evaluate the mechanical properties of cured epoxy modified with amine terminated poly (ethylene glycol) benzoate (ATPEGB) along with the comparison of results with change in chain length of ATPEGB.

ATPEGB prepared from poly (ethylene glycol) (PEG) of different molecular weights (200, 400 and 600) were used as modifiers for epoxy resin here. For effective toughening, different compositions were made by adding various concentration of each ATPEGB to epoxy. The impact, adhesive, tensile and flexural strengths of modified and unmodified epoxy were characterised and compared for each ATPEGB.

Modification of epoxy resin using each ATPEGB showed significant enhancement of mechanical strengths over unmodified epoxy. The modification caused a chemical linking between ATPEGB and resin which led not only to a phase separation but also to ensuring their intrinsically strong chemical bonds across the ATPEGB phase/resin matrix interface and this was the main cause to the improved mechanical strengths. The optimum results were obtained at 12.5 phr (parts per hundred parts of epoxy resin) concentration of each modifier.

The modifiers, ATPEGB, used in the present context were synthesised from PEG of molecular weight 200, 400 and 600. Besides, it could be synthesised from PEG of molecular weight 4,000 and 20,000, etc. and modification of epoxy resin could also be studied effectively by using these.

The method for enhanced toughness of cured epoxy was novel and could find numerous applications as surface coating and adhesive onto an intricate structure.

The purpose of this paper was to check effectiveness of amine functional chloroaniline acetaldehyde condensate (AFCAC) as a new curing agent for diglycidyl ether of bisphenol A (DGEBA) resin. For this purpose, first AFCAC was synthesised, characterised and then curing reaction was carried out.

Equimolecular mixture of AFCAC 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 were also carried out from those DSC exotherms. The mechanical properties, dynamic mechanical analysis (DMA) and thermogravimetric analysis (TGA) of cured epoxy were also reported.

DSC results reflected the effective first order curing reaction of AFCAC with epoxy resin. Mechanical properties reflected appreciable rigidity of AFCAC cured epoxy matrix and TGA showed that the cured epoxy networks were thermally stable up to around 297°C.

The curing agent AFCAC was synthesised by using chloroaniline and acetaldehyde in acid medium. There are some limitations for this procedure. The synthetic procedure is pH dependent. So reaction cannot be done at any pH value. The reaction must also be carried out at room temperature without any heating. To obtain low molecular weight curing agent, chloroaniline and acetaldehyde cannot be taken in equimolecular ratio because the equimolecular mixture of them produces high molecular weight condensate. This was shown in our previous publication. Some implications are also there. By changing amine and aldehyde other curing agents could be synthesised and the curing efficiency of those for epoxy resin could also be studied.

Experimental results revealed the greater suitability of AFCAC as curing agent for DGEBA resin and novelty of AFCAC cured matrix in the field of protective coating, casting, adhesives, etc.