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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.

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.

The adhesive and impact properties of cured epoxy resins, modified with amine‐randomised poly(2‐ethylhexyl acrylate) (ARPEHA) liquid rubber, as a function of the concentration of the liquid rubber, have been investigated. ARPEHA was synthesised by the reaction of the carboxyl‐randomised poly(2‐ethylhexyl acrylate) (CRPEHA) liquid rubber with 4,4′‐diaminodiphenyl sulphone. CRPEHA was synthesised by solution co‐polymerisation of 2‐ethylhexyl acrylate and acrylic acid. ARPEHA modified cured epoxy resins were formed by curing with an ambient temperature‐curing agent, triethylene tetramine. The modified epoxy resins were evaluated with respect to their adhesive and impact properties. The optimum properties were obtained at around 12.5 phr (parts per hundred parts of epoxy resin) of modifier. Analysis of the fracture surface using scanning electron microscopy indicated the presence of two‐phase microstructures.

To evaluate the efficiency of modifying epoxy resin using phenol‐nonyl phenol based polymer (PNPF) for toughness improvement and optimise the results of such a modification.

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

The modification of epoxy resin using PNPF showed significant enhancement of impact and adhesive strengths over the unmodified one. The modification caused the formation of a chemical linkage between PNPF and resin which led not only to a phase separation, but also to formation of intrinsically strong chemical bonds across the PNPF phase/resin matrix interphase, which was the main cause of the improved impact and adhesive strengths. The optimum results were obtained at 10 phr (parts per 100 parts of epoxy resin) of modifier.

The modifier, PNPF, used in the present context was synthesised from phenol, nonyl phenol and formalin using oxalic acid as catalyst.

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

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

To synthesise and characterise homo and copolymer of 4‐nonylphenyl methacrylate (NPMA) and styrene and to determine monomer reactivity ratios by the application of conventional linearisation methods such as Finemann‐Ross (F‐R) and Kelen‐Tudos (K‐T) methods.

New methacrylic monomer, NPMA with a pendant nonylphenyl group was copolymerised with styrene. All monomer and polymers (homo and copolymer) are characterised and subsequently the monomer reactivity ratio was determined.

The monomer reactivity ratios were determined by application of conventional linearisation methods such as F‐R (r₁=0.41±0.05; r₂=3.47±0.31), K‐T (r₁=0.43±0.19; r₂=3.54±0.09) methods. The thermogravimetric analysis (TGA) of the polymer in nitrogen reveals that it posses very good thermal stability in comparison to alkyl acrylates due to presence of pendant nonylphnyl group.

New methacrylic monomer, NPMA was synthesised by reacting nonylphenol dissolved in methyl ethyl ketone (MEK) with methacryloyl chloride in the presence of triethylamine as a base. Copolymers of NPMA with styrene were synthesised in MEK using benzoyl peroxide (BPO) as initiator under nitrogen atmosphere at different feed composition.

The method developed is a simple and easy method of copolymerisation of styrene with methacrylate to obtain copolymer of better properties.

The method developed is a novel method for enhancing the thermal, as well as surface adhesion, properties which has several applications in surface coatings and adhesives.

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.

The purpose of this paper is to synthesise, characterise and study polymerisation kinetics of novel 4‐nonylphenylmethacrylate (NPMA) polymer.

New methacrylic monomer, 4‐NPMA with a pendant nonylphenyl group was synthesised and characterised using various characterisation techniques. The free radical polymerisation kinetics study was done with the help of differential scanning calorimetry data.

The average heat of polymerisation (ΔHp) was found to be 685.43 J/g. Activation energy (E_a) of 95.86 kJ mol⁻¹ and frequency factor of (A) 3.4 × 10⁴ min⁻¹ was obtained using Kissinger method. The thermogravimetric analysis of the polymer in nitrogen reveals that it possesses very good thermal stability in comparison to alkyl methacrylates due to presence of pendant nonylphenyl group.

New methacrylic monomer, 4‐NPMA was synthesised by reacting nonylphenol dissolved in methyl ethyl ketone (MEK) with methacryloyl chloride in the presence of triethylamine as a base. Polymerisation of 4‐NPMA was carried out in MEK using benzoyl peroxide (BPO) as initiator under nitrogen atmosphere. The kinetics study of NPMA monomer with 1.1 wt% BPO was reported for evaluation of kinetic parameters by employing the Kissinger equation.

This is a simple and easy method of modification of methacrylate ester with phenyl groups to obtain a polymer of enhanced properties.

This is a novel method for enhancing the thermal as well as surface adhesion properties of methacrylate polymers which finds several applications in surface coatings and adhesives.

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.

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 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.