Thermal Analysis Studies Research Articles

Synthesis, characterization, thermal analysis and biological study of new thiophene derivative containing o-aminobenzoic acid ligand and its Mn(II), Cu(II) and Co(II) metal complexes

New ligand containing 2-(2,4-dioxo-4-thiophen-2-yl-butyrylamino)-benzoic acid (HL) merged moiety was synthesized and characterized by FT-IR, elemental analyses, mass spectra and 1H-NMR spectral. In the present study, the attempts were carried to form complexes of HL ligand with some transition metal ions (MnII, CuII and CoII) of well-defined at the (1:1) ratio of the components in the dimethyl sulfoxide (DMSO) solvent. All complexes have been studied by FTIR spectra, elemental analyses, thermal analysis, molar conductivity, electronic spectra and magnetic moment. The HL ligand produced as a bidentate chelate with interactive metal ions. All the results suggested octahedral geometry to complexes and have the formulae [M(HL)(Cl)2(H2O)2].nH2O where M = Mn(II), Cu(II) and Co(II). The IR spectra of the complexes were assigned and compared with the data in literature. The kinetic and thermodynamic results such as E*, ΔH*, ΔS* and ΔG* were calculated based o the TGA/DTG curves using Coats and Redfern and Horowitz and Metzger approximation methods. Furthermore, the resultant complexes were evaluated for the anti-bacterial and anti-fungal potential.
 
 KEY WORDS: 2-(2,4-Dioxo-4-thiophen-2-yl-butyrylamino)-benzoic acid, Transition metal complexes, FTIR, TGA, Antimicrobial test
 
 Bull. Chem. Soc. Ethiop. 2021, 35(1), 129-140.
 DOI: https://dx.doi.org/10.4314/bcse.v35i1.11

An organic benzimidazolium benzilate (BDBA) crystal: Structural description, spectral investigations, DFT calculations, thermal, photoluminescence, linear and nonlinear optical analysis

A single crystal of nonlinear optical material Benzimidazolium Benzilate (BDBA) with dimensions 0.2 × 0.2 × 0.18 mm3 was successfully grown by slow evaporation technique. The BDBA crystal crystallizes in the monoclinic crystal system with centrosymmetric space group C2/c. The intermolecular interactions were estimated through the Hirshfeld surface analysis. The vibrational modes of functional groups present in the compound were confirmed through attenuated total reflectance spectral studies. The molecular structure of BDBA was ascertained using NMR spectroscopic measurements, and the results confirmed the migration of proton from benzilic acid to Benzimidazole. Photoluminescence spectra indicate violet fluorescence emission peaks at 350 nm excitation. The optical band gap was 4.39 eV with a transmittance cut off wavelength of 282 nm. The extinction coefficient, optical and electrical conductivity, susceptibility, and polarization were calculated using UV–Vis-NIR spectroscopic measurements. The thermal properties were assessed by the simultaneous study of thermogravimetric (TG) and differential thermal analysis (DTA). It shows that the compound withstands up to a temperature of 148 °C. The crystal properties were theoretically computed using density functional theory (DFT) at the level of RB3LYP/6–311 + G(d,p) and computational studies such as natural bond orbital analysis, molecular electrostatic potential, Mulliken atomic charge distribution, and HOMO-LUMO were performed. The third order nonlinear optical (NLO) properties were studied using Z-scan studies.

Crystal structure, mosquito larvicidal & antifungal activity of 3‑tert‑butyl‑7-(2,3,4-trimethoxyphenyl)-4H-[1,3,4]thiadiazolo[2,3-c][1,2,4]triazin-4-one

The title compound 3‑tert‑butyl‑7-(2,3,4-trimethoxyphenyl)-4H-[1,3,4]thiadiazolo[2,3-c][1,2,4]triazin-4-one was prepared and characterized using single crystal X-ray diffraction, thermal & Uv-Vis analysis, FTIR, NMR (1H, 13C) and Mass spectral studies. The intercontacts in the crystal structure were analyzed and quantified using Hirshfeld surfaces computational method. Intermolecular hydrogen bonds C12—H12A…O4, C13—H13C…O4, C15—H15A…O2 and C16—H16B…O3 connects the molecule in the crystal structure. The intramolecular hydrogen bond of the type C—H …N was observed. Intercontacts H…H, O… H and N…H shows more contributions towards Hirshfeld surfaces. Thermal analysis indicates the title compound starts to degrade at 216.9 °C. In addition, mosquito larvicidal activity and antifungal activity were performed.

Thermal analysis and experimental study of cryostat for superconducting wiggler of the HEPS-TF

As an insertion device, the superconducting wiggler has been developed for about 40 years, the superconducting magnet of which is usually made of NbTi and set in a cryostat. The performance of the cryostat is vital to the success of the superconducting wiggler. In this paper, a cryostat of the superconducting wiggler with 32 poles and 2.6 T field for the High Energy Photon Source Test Facility (HEPS-TF) was developed in the Institute of High Energy Physics (IHEP). In the cryostat, a novel design of thermal structure and cooling capacity distribution was proposed. Compared with the conventional two thermal shields, the single thermal shield was adopted to simplify the mechanical design, which was extended to the outside of the vacuum chamber to decrease the heat loads at 4.2 K. The current leads were optimized to minimize the heat loads at 60 K. After the systematic thermal analysis and optimization, the total heat load was covered by the four Gifford-Mcmahon cryocoolers successfully. In the experiment, the measured heat load was 3.85 W with magnet current of 320 A and beam of 250 mA. And the residual cooling power was 0.65 W.

Optical detection of Al(III) and Cu(II) ions in an aqueous medium by using a simple probe possessing O,O-donor moiety

A commercially available probe (RS) has been reported for instantaneous selective colorimetric detection of Cu(II) and fluorescent detection of Al(III) ions in H2O:DMSO (90:10% v/v) medium. The probe displays a color change from pale yellow (λab 352 nm) to yellowish-green (λab 411 nm) with Cu(II) and a change in emission from green (λex 340 nm; λem 522 nm) to bluish-green (λem 489 nm) with Al(III) ions. The optical detection of these metal ions by RS is via the formation of tetragonally distorted octahedral RS-Cu(II) and tetrahedral RS-Al(III) complexes as evidenced from the results of UV-Vis, 27Al & 1H NMR, HRMS, EPR and thermal analysis studies. Job’s method indicates that the stoichiometry of both these complexes is 1:1. The probe's corresponding optical changes are particular for Cu(II) and Al(III) ions in the presence of other metal ions. RS displays high selectivity to these ions in a wide pH range. The limits of the detection of Cu(II) and Al(III) are as low as 66 nM and 0.83 µM, respectively. Further, RS could be applied as a fluorescent probe for observing Al(III) ions in living HeLa cells by carrying out cell image studies.

A recyclable cucurbit[6]uril-supported silicotungstic acid catalyst used in the esterification reaction

The esterification reaction used to prepare butyl paraben (BP) and propyl gallate (PG) catalyzed using a cucurbit[6]uril-supported Keggin-type silicotungstic acid (Q[6]-STA) catalyst has been investigated. The Q[6]-STA catalyst has been characterized using FTIR spectroscopy, XRD, SEM, EDS, thermal analysis, and surface area studies. Q[6]-STA was easy to prepare in high yield and exhibited some advantageous properties, such as high catalytic activity and its convenient recovery. Moreover, a reusability study showed that the Q[6]-STA catalyst was stable and active.

Luminescence and structural properties of ytterbium and erbium co-doped LaGaO3 nanophosphor for up-conversion by polyol method

Ytterbium and erbium co-doped lanthanum gallate (LaGaO3) up-conversion phosphors have been synthesized using polyol method followed by heating at 1000°C. From Fourier transform infrared (FTIR) spectroscopy and thermal analysis studies of as prepared sample, formation of hydroxy carbonate precursor has been confirmed. This precursor undergoes two step decomposition leading to the formation of LaGaO3 phase. Detailed X-ray diffraction studies confirmed the formation of orthorhombic LaGaO3 phase with distorted GaO6 octahedra and distorted LaO12 cuboctahedra. As the annealing temperature increased from 1000°C to 1200°C, green to red ratio (GRR) as well as lifetime values increased and this is explained based on the increase in crystallite size from 40 nm to 95 nm and associated decrease in the extent of quenching (non-radiative) processes. Variation in the “n” values accounts for the observed increase in the GRR values corresponding to 1000°C and 1200°C annealed samples with increase in laser power.

A case study of thermal analysis of a solar assisted absorption air-conditioning system using R-410A for domestic applications

Sustainable future and green environment goals quest for the development of technologies to utilize renewable energy resources to power the people. This study focuses on the designing, modelling, and simulation of an absorption solar air-conditioning system. Key performance parameters are identified, optimized for maximum efficiency and simulated in transient energy simulation software TRNSYS ®. The designed model comprises five thermal loops: a solar loop consisting of an evacuated glass tube solar collector having R-410A as heat transfer fluid in it and a heat exchanger heat tank, second loop has an absorption chiller, and an auxiliary furnace with hot water stream, third is the cooling tower loop, the fourth loop is of chilled water from the chiller and the final thermal loop is for air delivery of cooling to each room. The system is simulated using Lahore, Pakistan's climate conditions and offered a good tendency for the proposed system to meet air-conditioning demand at the domestic level. The average collector outlet temperature value of 78 °C has been recorded throughout the week. Collector provides useful energy gain at an average rate of 71,065 kJ/h. Average storage tank temperature at the outlet of heat exchanger is 92°C. Average room temperature values of three rooms are 27°C, 30°C and 19°C respectively.

Study of Solidification Thermal Analysis, Microstructure and Mechanical Characteristics of A384 Cast Alloy Treated with Rare Earth (Sm, Tb, Ce and La) Elements

This article investigates the refining and modification response of cast A384 aluminium alloy induced by the addition of rare earth elements and the impact on microstructural and mechanical performance. Thermal analysis technique is used to develop cooling curves, and the first and second derivatives were obtained for each solidification cooling curve and used to identify the sequence of reactions and phase crystallization during solidification without and with Sm and/or Tb or La and/or Ce additions. Microstructural characteristics, hardness, strength, wear and corrosion resistance are evaluated. Optical and SEM observations in addition to EDS analysis provided more details regarding the intermetallic precipitates formed, which revealed the presence of intermetallic phases rich in Sm and/or Tb as well as Ce and/or La. It is observed that the added rare earth metals Sm plus Tb to A384 alloy improved the alloy strength and hardness due to their refining and modification effect. Furthermore, enhancement of both wear and corrosion resistance is achieved through the addition of 1.0 wt.% Samarium (Sm) to A384 samples.

Determining the temperatures to which the bone was heated in archaeological contexts. Distinguishing between boiled and grilled bones

A study carried out in fresh cow (Bos taurus) cortical-femur bones which allows determining the maximum annealing temperature to which a bone was subjected is shown. It is focused on temperatures near the ones used in culinary activities. Mechanical spectroscopy, optical microscopy, differential thermal analysis and thermogravimetry studies are used in the present work. The study takes into account the behaviour of the thermal denaturation processes from the remnant collagen as a function of temperature. The survey of the relaxation process related to the triple helix to random coil transition from the residual collagen which occurs at 510 K/237 °C, is proposed as a potentially useful tool for determining that the bone was not previously heated above this temperature. In addition, by using mechanical spectroscopy a procedure for discriminating between grilled- and boiled-bones is shown. Likewise, a reference chart of the thermodynamic states of denaturation of collagen in the bone as a function both of temperature and cooking mode is reported. The relationships between the denaturation stages and the responses from mechanical spectroscopy and differential thermal analysis are also shown.

The Effects of Different Chemical Treatment Methods and Maleic Anhydride Grafted Polyethylene on the Mechanical and Thermal Properties of <i>Alpinia galanga</i> Fiber Reinforced Polyethylene Composites

In this study, the effect of different treatments and the addition of maleic anhydride grafted polyethylene (MAPE) on the mechanical and thermal properties of Alpinia galanga (AG) fiber/high-density polyethylene (HDPE) composites were investigated. The AG fibers were pretreated with sodium hydroxide (NaOH) and then treated with 3-aminopropyltriethoxysilane (3-APE) as well as treated with p-toluenesulfonic acid (PTSA). The samples were first prepared by melt blending method before being injected to specimen dumbbell shape using an injection moulding machine. Three different fiber loadings were studied, such as 3, 6, 10 and 15 wt%. The tensile test results revealed that the NaOH and 3-APE treatments increased the tensile strength of AG/HDPE composites with the addition of MAPE at all fiber loadings, whereas tensile strength of PTSA treatment improved at 3 wt% fiber loading. The morphological studies confirmed a better adhesion between treated fiber and HDPE matrix with the inclusion of MAPE. Thermal analysis study showed that NaOH, 3-APE and PTSA treatments on AG fibers improved the thermal stability of the composites with an addition of MAPE by delaying the thermal degradation of the composites. The water absorption test proved NaOH and 3-APE treated fiber exhibited lower water absorption than other composites with the inclusion of MAPE. Overall, the results indicated that chemical treatment with NaOH and 3-APE with the presence of MAPE is a good approach towards the development of natural fiber composites.

Thermal Analysis and Kinetic Study of Indian Almond Leaf by Model-Free Methods

ABSTRACT Thermogravimetric analysis of Indian almond leaf was carried out at four different heating rates such as 5°C/min, 10°C/min, 15°C/min and 20°C/min. The kinetic study was performed using model free methods and the kinetic parameters were calculated by Kissinger, Friedman, KAS and FWO models. Thermogravimetric analysis resulted that the Indian almond leaf showed four stages of decomposition. Most of the mass loss occurred at stage II (188–460°C) owing to the simultaneous decomposition of cellulose, hemicellulose, and lignin. The shifting of pyrolysis curve occurred with increase of heating rate due to the limitation of heat transfer. The rate of mass loss decreased while increasing the heating rate due to the presence of more inert content i.e. ash and less volatile matters. The mean activation energy calculated by Kissinger, Friedman, KAS, and FWO showed as 52.67, 45.53, 73.73, and 72.28 kJ/mole. The mean activation energy of different leaves reported by earlier researcher was compared with the activation energy of Indian almond leaf and concluded that it stick to the range of activation energy of reported leaves.

Effect of composition on thermal stability and microstructural behaviour of non-prototype material (CaO-Fe2O3)

The role of simulant materials becomes necessary for the predictive study of the nuclear severe accident phenomena due to its similarity with corium (a liquid form of UO2 and steel). Since simulant material is eco-friendly and has similar properties to corium, it has been widely used in the research field of severe accident management. In this study, material CaO-Fe2O3 a non-eutectic binary mixture is considered for characterization purpose to address the thermophysical properties at different compositional ratios. The CaO-Fe2O3 powder mixture was prepared in mortar for 40 minutes manually to form a homogeneous mixture and then cylindrical pellets prepared at five different ratios with the help of the phase diagram. Further, these pellets were heat-treated at 1200°C for three hours soaking time to address its thermal stability in a programmable electric furnace. Finally, pellets ground into powder form manually for further characterization. Initially, the weight loss analysis was reported by measurement of dimensions of pellets before and after heat treatment. The thermal properties, phase analysis, and morphological studies have been carried out through DSC, XRD and FE-SEM in laboratory and results were discussed in the context of the property of ideal simulant materials used for the study of nuclear severe accidents. The melting point of all the samples were found stable (1200°C-1230°C) and values of activation energy and specific heat were well synchronized between with and without heat-treated samples. Dislocation density of samples increases significantly with increasing the proportion value of calcium oxide after heat treatment.

Development and thermal behavior of a new type of polymer materials with reduced combustibility based on epoxy–amine composites modified with copper(II) hexafluorosilicate

The polyamine chelate complex of copper(II) hexafluorosilicate—[Cu(eda)(deta)]SiF6—(a flame retardant-hardener of epoxy resins) and CuSiF6-containing epoxy–amine composites—DGEBA/pepa-CuSiF6—with reduced combustibility and with the varied content of CuSiF6 were obtained in the DGEBA–pepa–CuSiF6 system (pepa—H2N[–C2H4NH–]nH, n = 1 (eda—NH2C2H4NH2) and n = 2 (deta—NH2C2H4NHC2H4NH2); DGEBA—bisphenol A diglycidyl ether). These samples were characterized by IR spectra, thermal analysis and flammability studies. The results of Thermogravimetric analysis (TGA) showed that thermal decomposition of [Cu(eda)(deta)]SiF6 is completed at 368 °C and the maximal temperature of the gaseous combustion products was 488 °C. TGA data for DGEBA/pepa-CuSiF6(22) confirm that the incorporation of [Cu(eda)(deta)]SiF6 into DGEBA significantly increases thermal stability and anti-flammability of CuSiF6-containing epoxy–amine composites. Ignition and self-ignition temperatures have been measured for all CuSiF6-containing epoxy–amine composites in accordance with ASTM D1929-16. Depending on the quantity of added CuSiF6, the tignition for this type of composite increases by 15–34 °C, and the tself-ignition increases by 25–58 °C compared to DGEBA/pepa. The flammability of the samples was evaluated by means of UL94 BH methods. The burning rate of the DGEBA/pepa-CuSiF6(66) and DGEBA/pepa-CuSiF6(88) epoxy–amine composites is severe slowed down (these samples do not propagate flame), while rburn. value for the unmodified epoxy–amine sample (DGEBA/pepa) is 25.13 mm min−1.

Corrosion mitigation performance of disodium EDTA functionalized chitosan biomacromolecule - Experimental and theoretical approach

Disodium ethylenediaminetetraacetate salt is known for its excellent coordinating properties with the metal ions. The present study deals with the investigation of the prepared Disodium EDTA functionalized chitosan in corrosion inhibition for mild steel in 1 M HCl. The modified chitosan was characterized by spectral studies, thermal analysis, and Zeta potential studies. The corrosion inhibition efficiency (%) was evaluated using the gravimetric method and electrochemical studies. The electrochemical studies included potentiodynamic polarization, linear polarization resistance, and electrochemical impedance methods. The modified chitosan polymer showed an inhibition efficiency of 96.63% for 500 ppm at 303 K. Adsorption process obeyed Langmuir isotherm. Experimental results and theoretical calculations endorsed initial physisorption followed by a chemisorption process. Surface characterization studies supported the formation of a protective film that enabled the inhibition process. Density functional theory, Monte Carlo studies, and molecular dynamics simulation studies show a good agreement with the experimental results. Two-way Analysis of Variance was performed to test the influence of immersion period and inhibitor concentration on the corrosion rate using the statistical software IBM SPSS 20.0. A quartic model was generated as the best fit with the highest R2 value of 0.973. Design Expert software was employed for statistical modeling fit.

New Mg(II) and Ca(II) Mixed Strontium Squarates: Structural Characterization, DNA/BSA Interaction, Antioxidant and Anticancer Activities

New mixed alkaline earth metal squarates, viz [Sr0.965Mg0.035(C4O4)(H2O)2]·H2O—(1) and [Sr0.88Ca0.12(C4O4)(H2O)3]—(2) have been synthesized and characterized by single-crystal X-ray diffraction, thermal analysis, and biological studies, EB-CTDNA binding, BSA binding, antioxidant and cytotoxicity activity. The complexes 1 and 2 crystallized in triclinic and monoclinic space groups with eight and nine coordination number, respectively, from the reaction mixture of squaric acid and the respective metal nitrates in aqueous medium at pH 7. The complexes on thermal analysis show that they yield mixed metal carbonates at 544 °C as residue. Their interaction with EB-CTDNA evaluated by emission method substantiates the intercalative mode of binding. The protein binding (BSA) study by the fluorescence quenching method reveals that the complexes bind strongly with BSA. Antioxidant property analysis shows that they exhibit a strong radical scavenging ability against ABTS, DPPH and NO radicals. The in vitro cytotoxicity of the complexes examined for human breast cancer (MCF-7) and lung cancer (A549) cell lines exhibit substantial cytotoxic property. AO/EB and DAPI staining methods support that they induce apoptosis and nuclear fragmentations in MCF-7 and A549 cell lines.

Cu (II), Zn (II), and Ce (III) metal complexes as antimicrobial pigments for surface coating and flexographic ink

Metal complexes, which were prepared from the reaction of an N‐salicylidene(4‐aminotoluene‐3‐sulfonic acid) Schiff base ligand (H2L) with Cu (II), Zn (II), and Ce (III), were characterized and confirmed by elemental analysis, molar conductance measurement, melting point, Fourier transform infrared (FT‐IR) spectroscopy, proton nuclear magnetic resonance (1H NMR), electronic spectra, magnetic susceptibility, thermal analysis, and qualitative and quantitative antimicrobial studies. The geometry of the compounds was optimized using the semiempirical PM3 Hamiltonian with Restricted Hartree–Fock (RHF) and root‐mean‐square (RMS) gradient of 0.05 kcal/mol. The ligand and its metal complexes were physically incorporated into a water‐based paint and flexographic ink formulation to study their antimicrobial properties and performances as metal‐complex pigments. The results of their performance tests further enhanced their applications as pigments. The mechanical resistance of the prepared paint and ink was also studied to evaluate the possible drawbacks that were associated with the addition of the prepared pigments. Compared with the blank sample, the studies indicated that the physical incorporation of Cu complexes slightly enhanced the mechanical properties of the painted films (the gloss values, hardness, and adhesion) and printed paper (gloss, color strength [density], and abrasion resistance) according to the American Society for Testing and Materials (ASTM). Further, regarding the antimicrobial test, the obtained results can be represented according to the following activity order: the prepared ligand > Zn complex > Ce complex > Cu complex before or after the incorporations of the paint and ink.

Dinuclear copper(II) complex of containing N,N-diisopropyl,N'-3-propylamide-ethylenediamine and dihydroxo bridge; Solvatochromic and Thermochromic

The synthesis and characterization of dinuclear [LCu(m-OH)2CuL](ClO4)2, complex with a tridentate N,N-diisopropyl,N'-3-propylamide-ethylenediamine hemilabile ligand (abbreviated L) is reported. The dinuclear complex was characterized by elemental analyses, molar conductance, thermal analysis and spectral studies. In the complex two copper centers are 5-coordinated and bridged through two hydroxo groups. Thermo- and solvatochromic behaviors of the complex were investigated by visible spectroscopy. Its reversible thermochromism (blue ↔ green) is due to breakage and re-coordination of Cu-O(amide) moiety in acetonitrile solution. The solvent-dependent absorption maxima, max, was studied by a stepwise multiple linear regression (SMLR) analysis to determine the best model describing the resulting positive solvatochromism. The statistical results demonstrated that among different solvent parameters, donor number (DN) is a dominant parameter responsible for the redshift in the d-d absorption band of the complexes with increasing its values.

Crystal structure, spectroscopic, DFT calculations and antimicrobial study of the Cu(II) complex bearing second-generation quinolone ofloxacin and 2,2′-bipyridine

Cu(II) complex of second-generation quinolone ofloxacin with 2,2′-bipyridine formulated as [Cu(ofx)(2bpy)(H2O)].ClO4·2H2O (1) [ofx = ofloxacin, 2bpy = 2,2′-bipyridine] has been synthesized. The coordination possibility of the ofx and 2bpy towards metal ion was proposed using single-crystal X-ray diffraction analysis (SCXRD), IR, UV–Visible, EPR, thermal analysis, molar conductance, and elemental analysis. The interaction of Cu(II) with the deprotonated ofloxacin ligand resulted in the formation of the mononuclear complex of the type [Cu(ofx)(2bpy)(H2O)].ClO4·2H2O. Single crystal X-ray crystallography data revealed a five-coordinate, distorted square-pyramidal arrangement in the complex. The complex crystallizes in the triclinic system with a = 10.2192(13), b = 12.7080(19), c = 12.8156(16) Å, and space group P–1. The measurement of the complex molar conductance in DMSO (10−3 M solution at 25 °C) revealed the electrolytic nature of the complex and was of the 1:1 type. The presence of coordinated water molecules and the metal oxide in the final product was determined by thermal analysis studies. DFT calculations were carried out for the complex ion and the two ligands using the B3LYP/631-G(d) level of theory and the HOMO-LUMO energy gap was evaluated. The results showed that the complex with the lowest energy gap value (0.951 eV) is more reactive than the ligands. The ligand and its copper (II) complex were screened in order to evaluate the antimicrobial activity by measuring the inhibition zone (mm). The results showed that the metal complex was observed to be more active than the parent ligand.

Novel epoxy resin adhesives toughened by functionalized poly (ether ether ketone) s

Epoxy resins are inherently brittle due to their high crosslink density. Hybridization of epoxies with a thermoplastic phase is an effective solution for reducing the brittleness and improving the toughness without impairing the thermal and mechanical properties. The present study focuses on the development of a novel room temperature curable epoxy resin by blending with different proportions of hydroxyl terminated poly (etheretherketone)s (PEEKTOH) as thermoplastic toughening agent. The systems were cured using triethylenetetramine (TETA). Isothermal rheological studies showed that, incorporation of PEEKTOH phases reduced the gelation time of the blend from 175 min to 30 min. The glass transition temperature of the blends were improved marginally (from 74 to 80 °C) as evidenced by dynamic mechanical thermal analysis studies. The toughened and the unmodified systems were examined for their adhesive properties on aluminium substrates. It was noted that, about 19% improvement in lap shear strength (LSS) was achieved for the toughened adhesive. Higher proportions of PEEKTOH in the epoxy matrix led to increased viscosity which consequently reduced the wetting characteristics, as proven by contact angle measurements. The fracture toughness of the cured blends improved up to 86%. Fracture morphology evaluation by scanning electron microscopy (SEM) showed a brittle fracture for the unmodified epoxy and a phase separated morphology for the toughened blends. Transparency was reduced in the toughened formulations due to phase separation of PEEKTOH.