Mole Proportions Research Articles

Laminar burning velocity of ethanol-ethyl acetate mixtures in air

Alcohols, esters, and their mixtures are ubiquitous in the process industry. However, safety data remain limited, especially for mixtures. In this work, the laminar burning velocity, Sl, of ethanol-ethyl acetate mixtures in air was investigated (at 90 °C and atmospheric pressure) through computations performed using three different detailed chemical kinetic mechanisms, and measurements obtained from pressure time histories recorded during closed vessel explosion experiments. Computations were run varying the equivalence ratio, φ, from 0.6 to 1.7, and the mole fraction of ethanol in the fuel mixture from 0 (only ethyl acetate) to 1 (only ethanol). For all systems, explosion experiments were carried out at φ = 1.1, i.e., the composition at which, according to calculations, Sl achieves its maximum value. Regardless of the kinetic mechanism, reasonable agreement is found between computed and experimental data, including experimental data retrieved from the literature for ethanol and ethyl acetate. Results show that the behavior of ethanol-ethyl acetate is bounded between the behaviors of ethanol and ethyl acetate, approaching the former/latter as the mixture is enriched in ethanol/ethyl acetate. Over the whole range of equivalence ratios explored, the values of Sl for ethanol-ethyl acetate are smaller than those obtained by averaging the corresponding values of ethanol and ethyl acetate according to their mole proportions in the fuel mixture. This is also confirmed experimentally. A simple Le Chatelier’s mixing rule-like formula is proved to predict values of Sl that closely match both computed and experimental data, suggesting that the nature of the interaction between ethanol and ethyl acetate is predominantly thermal rather than chemical.

Development of novel heterogeneous cobalt acylpyrazolone catalyst: Synthesis, characterization and selective oxidation of styrene to benzaldehyde

Cobalt acylpyrazolone complex was prepared and characterized using various spectral methods, FT-IR, TGA, UV–visible, DRS, magnetic study, and single crystal XRD. A heterogeneous catalyst consisting of neutral alumina and cobalt complex was synthesized and characterized using various physicochemical methods and successfully applied to styrene oxidation without a solvent. The effects of the reaction variables (mole proportion of the reactantto hydrogen peroxide and TBHP, quantity of the catalyst, reaction period and reaction temperature) were investigated. No appreciable catalytic activity reduction occurred when the catalyst was utilised again. The catalyst's recycling is verified by infrared and diffuse reflectance spectra confirming that the catalyst was intact and notdestroyed following the process. The work's unique feature is its benzaldehyde selectivity under benign reaction circumstances.

Evidence-Based Communication to Increase Melanoma Knowledge and Skin Checks

Rates of melanoma—the deadliest form of skin cancer—have increased. Early detection can save lives and patients have a critical role to play in checking their skin. We aim to identify health communication messages that best educate the public and increase intentions towards skin checks. After viewing messages intended to increase melanoma knowledge, participants correctly identified a greater proportion (74.6% vs 70.4%) of moles (mean number 17.9 [95% CI 17.5, 18.3] vs 16.9 [95% CI 16.6, 17.3], P < .001, ηp2 = .03) and had knowledge of more melanoma warning signs (5.8 [95% CI 5.7, 5.8] vs 5.6 [95% CI 5.5, 5.7], P = .01, ηp2 = .02). After viewing messages intended to increase self confidence in checking their skin accurately, they were also more likely to report greater intentions to do a skin check on a scale of 1-5 (3.8 [95% CI 3.7, 3.9] vs 3.6 [95% CI 3.4, 3.7], P = .005, ηp2 = .02). Online melanoma messages aimed at increasing both melanoma knowledge and skin-check confidence may be most effective in improving the accuracy of skin self-exams and intentions to do them.

Amoxicillin degradation in persulfate activation system induced by concrete-based hydrotalcites: Efficiency, mechanism, and degradation pathway

Concrete-based hydrotalcites (CLDHs) was synthesized from concrete to activate peroxysulphate (PDS) for amoxicillin (AMX) degradation. The proportion of Fe2+ in CLDHs was optimized, the effects of initial pH, CLDHs/PDS ratio and PDS dosage on AMX degradation were investigated. To clarify the removal mechanism and degradation pathway of AMX, a quenching test was conducted to identify the active species in the system, the reactive sites of AMX were predicted by density functional theory (DFT) calculation, and the degradation intermediates of AMX were analyzed by liquid chromatography-mass spectrometry (LC-MS). Furthermore, the toxicity of AMX and its degradation intermediates were evaluated based on quantitative structure–activity relationship (QSAR). The results showed that when the molar ratio of M2+/M3+ in CLDHs was 2:1, the optimal mole proportion of Fe2+ in M2+ was 33 %. The activation system obtained better AMX removal as pH value ranged in 4–6, and the optimum CLDHs/PDS mass ratio was 2.6. The removal of AMX by CLDHs-PDS system was the coordination of SO4·- and HO·, and the contribution of SO4·- was slightly higher than that of HO·. Based on DFT calculations and intermediates identification, the degradation pathway of AMX in CLDHs-PDS system was proposed, including quaternary ring opening reaction and hydroxylation reaction. The ecotoxicological assessment showed a slight increase in toxicity of intermediates during AMX degradation. Therefore, appropriate time extension is required to ensure the full mineralization of AMX.

Influence of amino acids on bacterioplankton production, biomass and community composition at Ocean Station Papa in the subarctic Pacific

Bacterioplankton play a central role in carbon cycling, yet their relative contributions to carbon production and removal can be difficult to constrain. As part of the Export Processes in the Ocean from RemoTe Sensing (EXPORTS) program, this study identifies potential influences of bacterioplankton community and dissolved organic matter (DOM) composition on carbon cycling at Ocean Station Papa in August 2018. Surface (5–35 m) bacterioplankton production rates and stocks spanned a 2- to 3-fold range over the 3-week cruise and correlated positively with the DOM degradation state, estimated using the mole proportion of total dissolved amino acids. When the DOM was more degraded, 16S rRNA gene amplicon data revealed a less diverse bacterioplankton community with a significant contribution from members of the Flavobacteriaceae family. Over the course of 7–10 d, as the DOM quality improved (became less degraded) and bacterioplankton productivity increased, the responding bacterioplankton community became more diverse, with increased relative contributions from members of the SAR86, SAR11 and AEGEAN-169 clades. The cruise mean for mixed layer, depth-integrated bacterioplankton carbon demand (gross bacterioplankton production) was 5.2 mmol C m−2 d−1, representing 60% of net primary production, where the difference between net primary production and bacterioplankton carbon demand was less than sinking flux at 50 m. The concentrations of dissolved organic carbon (cruise average of 58.5 µM C) did not exhibit a systematic change over the cruise period. Therefore, we hypothesize that carbon supplied from gross carbon production, values that were 2- to 3-fold greater than net primary production, provided the carbon necessary to account for the sinking flux and bacterioplankton carbon demand that were in excess of net primary production. These findings highlight the central contributions of bacterioplankton to carbon cycling at Ocean Station Papa, a site of high carbon recycling.

Synthesis and characterization of new metal complexes of thione and phosphines Ligands

The complexes containing mixed of ligands [5-(3-chlorophenyl) -1,3,4-oxadiazole-2-thione(CPoxSH)] and diphosphines Ph2P(CH2)nPPh2 (diphos)(n=1-4), are prepared by the reaction of [Hg(CPoxS)2] or [M(H2O)2(CPoxS)2] (M = Co, Ni ) with one mole proportion of the diphosphine Ph2P(CH2)nPPh2 gave tetrahedral complexes of the type [Hg(CPoxS)2(diphos)]. While gave an octahedral complexes with cobalt(II) and nickel(II) ions of the type [M(H2O)(CPoxS)2(diphos)] when (M = Co and Ni ) receptivity.&#x0D; The prepared complexes were characterized by molar conductivity, elemental analysis, IR, 1H, 13C-{1H} and 31P-{1H} n.m.r.

Insights into the luminescent properties of poly(phenylene sulfide)-grafted metal-organic framework (Tb–MOF–PPS) copolymers

In this study, a novel poly(phenylene sulfide)-grafted metal-organic framework (Tb–MOF–PPS) was fabricated. Initially, 2,5-dichloroterephthalic acid and TbCl3·6H2O were used as raw materials to synthesize the dihalogenated MOF (Tb–MOF) through ultrasound irradiation and hydrothermal methods. Subsequently, Tb–MOF was added at different mole proportions (2.5, 5, 7.5, and 10%) for the copolymerization of PPS, and a serial of Tb–MOF–PPS composites were successfully obtained. Fourier transform infrared spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy proved that the Tb–MOF was covalently connected to PPS. The introduction of the Tb–MOF had no evident influence on the thermal properties of the composites. Additionally, the fluorescence characteristics revealed that the fluorescence excitation and emission spectra of the composites had a large redshift compared with that of PPS and possessed visible-light photoluminescence properties. These results indicate that the composites obtained can be used as optical sensors.

Changes in diagnostic sensitivity, incidence and presentation of complete and partial hydatidiform mole over the years

ObjectiveMolar pregnancy is the most common type of gestational trophoblastic disease. Several recent reports have described changes in the clinical representation, the incidence and the diagnostic sensitivity of molar pregnancy. These changes could be due to widespread use of transvaginal ultrasound and beta-hCG testing in the management of routine first-trimester investigations. Study designThis is a retrospective study of 144 women diagnosed with partial or complete mole at a regional medical center during 2007–2020. Incidence, demographics, clinical features and diagnostic sensitivity were compared between 2007 and 2014 and 2015–2020, and attempts were made to understand the bases of the changes between the time periods. ResultsSixty-two moles were diagnosed during 2007–2014 and 82 during 2015–2020. The proportions of complete moles in the respective periods were 65% (40) and 18% (15). From the earlier to the later period, the incidence and proportion of complete moles decreased, and of partial moles, increased. The median gestational age at diagnosis of molar pregnancy was 9.3 weeks. In the later period, women presented less frequently with vaginal bleeding, though this remained the most common presenting symptom. The proportion of women who underwent surgical evacuation of the uterus due to suspected molar pregnancy decreased, as did the proportion of moles that was suspected in ultrasound evaluation (P < 0.001). ConclusionThe proportion of complete moles decreased between the periods examined. Gestational age at diagnosis was similar to data from 1994 to 2013. Some typical presenting symptoms of molar pregnancy decreased. However, earlier diagnosis of missed abortion can miss diagnoses of molar pregnancy.

Novel method for determination of Zinc in some pharmaceutics using new prepared reagent of methyl phenol

This work studied the amalgamation and portrayal of another Azo-Schiff base ligand and its utilization of zinc in certain medications. Azo 2-(E)- (1H-benzo[d]Imidazol-2-yl)diazenyl)- 5-((E)- (4-Chlorophenylimino)methyl)phenol.(BIACMebp) has been incorporated after the closely resembling system and Al-Adilee et.al., with some adjustment in a two-venture measure, in the initial step, 2-Amino benzimidazole (1.33 g) was blended in with hydrochloric corrosive 3ml In (thirty mL) refined water and diazotized under 5 °C with sodium nitrite NaNO2 (0.75 gm,0.01mol, broke up in 20 ml refined water) was included drops, and in the next step the diazonium chloride compound is then combined with 3-(4-Chlorobenzylideneamino)phenol(CBAP) (2.31 gm,0.01 mol), disintegrated in combination from 60 ml ethanol and 18 ml sodium hydroxide(5%) Pour the blend for 1 hour at a temperature of 5-0 m. The readied azo where inspected by various phantom procedure in wording, C.H.N natural investigations, metal substance, FT-IR, UV-Vis, 1H-NMR and mass spectra contemplates. The metal ligand proportion (M:L) in alcoholic watery arrangements controlled by mole proportion methodand it demonstrates 1:1 for the complex. Additionally, the strength constants for the complex with zinc has been determined frightfully by UV-Vis technique. All outcomes show this complex has high strength. The systematic applications have been achieved in medication (zinc sulfat) for several companies (zincodin (Aktive) 25 mg, Zinc (Kontam) 35 mg, Zinc Sulfate (Jink.) 20 mg.

Mechanistic model for the batch extraction of oil from avocado seeds available for biofuel production

ABSTRACT Broad assessment is being directed everywhere by the researchers on the world to identify the alternative sources for eco-friendly fuel. In the present investigation, biodiesel was integrated from the waste avocado seeds. Since the seed is a bio-squander that has the fundamental supplements and unsaturated fats, there is a need to use this waste and convert them into a valuable item. The biodiesel production process includes two-step processes. The first step is extraction of oil from the seed by using ethanol as a solvent. The viable extraction was obtained with the optimum conditions were found to be at 80°C, with the solvent to feed the proportion of 7:2, 3 hours of extraction time. Kinetic models were developed for the extraction processes with an R2 value of 0.959 and 0.989. The second step is producing biodiesel from the extracted oil by transesterification process. Operating conditions used for the trans-esterification reaction were observed to be 60°C, KOH to oil weight proportion of 1% and oil to methanol mole proportion 1:6. The biodiesel properties were estimated and contrasted and benchmarks which demonstrated that the biodiesel could be utilized as an elective vitality asset in diesel engines. This research work comprises two principle goals. Initially, a numerical model was obtained to anticipate the best states of extraction of lipids from a dried avocado seed. Second, utilizing the lipid separated from the seed, the biodiesel must be produced. GCMS examined the acquired biodiesel, and the diesel properties were investigated.

Preparation and Characterization of Capric-Lauric Acid/Silicon Dioxide Nanocapsules as Phase Change Energy Storage Materials

Capric acid (CA)-lauric acid (LA)/silica (SiO2) nanocapsules were fabricated in this paper. The core material was acted by CA-LA eutectic mixture, and the shell material was supported by SiO2. The phase identification, chemical composition, micrograph, and thermal property of as-prepared samples were analyzed based on X-ray diffraction, Fourier transformation infrared spectroscope, Scanning electron microscope and Differential scanning calorimety, respectively. These results displayed that CA-LA eutectic mixture was well encapsuled into SiO2 pore network. The CA-LA/SiO2 nanocapsules were spherical with uniform particle size of about 100 nm. When the mole proportion of CA:LA was 65:35, the phase transition temperature of nanocapsules was measured as 18.98 °C, and latent heat was confirmed as 83.06 J/g. The phase change temperature of the nanocapsules was basically consistent with the calculation value of pure CA-LA eutectic, and latent heat was about 58% of the theoretical value, signifying a high encapsulation efficiency. Therefore, CA-LA/SiO2 nanocapsules as PCMs could provide thermal energy storage for buildings.

Strength effect of alkali activated red mud slag cement in ambient condition

The excess demand for cement in construction area is relevant compatible to maxima utilization of industrial solid waste as an alternation of binding material. Since the disposal of red mud turns to major environmental issue for its alkaline nature, so this research was to evaluate the viability of red mud as a cementitious material. This type of material was developed by the addition of granulated slag and red mud with three different proportion i.e. 30/70, 50/50, and 70/30. Those solid compositions were activated with the low concentration of the alkali solution prepared by sodium hydroxide pellet and sodium silicate powder varying as mole proportion of SiO 2 -Na 2 O from 0 to 1.5 mol. Best compressive strength values were obtained by ARSC 50 containing 50% slag and 50% red mud, but activated by SN 1.5 with the value 90.1 MPa after 60 days of curing age in ambient condition. Hydration characteristics of ARSC 50 were observed by XRD, SEM. Ettringite and amorphous C-S-H gel are the prime factors of strength development of ARSC. This paper provides a major solution of utilization of red mud and preservation of energy and natural sources.

Epitope imprinting of alpha-synuclein for sensing in Parkinson's brain organoid culture medium

Parkinson's disease (PD) is a progressive nervous system disorder that affects movement, whose early signs may be mild and unnoticed. α-Synuclein has been identified as the major component of Lewy bodies and Lewy neurites, which are the characteristic proteinaceous deposits that are the hallmarks of PD. In this work, three alpha-synuclein peptides were synthesized as templates for the molecular imprinting of conductive polymers to enable recognition of alpha-synuclein via ultrasensitive electrochemical measurements. The peptide sequences encompassed specific residues where mutations are known to accelerate PD (though the target sequences, in this study, were wild-type.) The different peptide targets were all successfully imprinted, but with differing imprinting effectiveness, probably owing to differences in target carboxylic acids (which can bind to the aniline (AN) m-aminobenzenesulfonic acid (MSAN) MIP polymers.) Composition of the imprinted polymer, (the mole proportions of AN and MSAN), and the concentrations and sequences of imprinted peptide templates were optimized by measuring the electrochemical responses to target peptides. The imprinted electrode can detect alpha-synuclein at fg/mL levels, and was therefore used to measure alpha-synuclein in the culture medium of human brain organoids generated from normal and idiopathic PD patients.

Research on systems for producing liquid hydrogen and LNG from hydrogen-methane mixtures with hydrogen expansion refrigeration

In industrial production processes, gas mixtures with hydrogen and methane as main useful components are often obtained as by-products, which are often not well utilized. In this paper, an innovative approach is proposed to produce both liquid hydrogen and LNG from industrial by-products with H2 and CH4 as main components. Taking the purified hydrogen-methane mixtures as the research object, four different separation-liquefaction processes (namely Open Loop-N2, Open Loop-H2, Closed Loop-N2, Closed Loop-H2) are constructed and optimized, with refrigeration supplied with hydrogen expansion at the cryogenic section and nitrogen or hydrogen expansion at the precooling section. A distillation column is set up before the mixture enters the cryogenic section to facilitate the production of high purity methane and hydrogen products. Every system achieves excellent energy integration, and the load of condenser and reboiler in the column is borne by the hydrogen expansion cycle in the cryogenic section. For each process, the influence of hydrogen mole proportion in feed gas between 10% and 90% on the process performance is analyzed. The results show that the purities of LNG and liquid hydrogen products obtained by the system are higher than 99.99%, and the specific energy consumption of the systems is within 18.01–41.72 kWh·kmol−1 for different situations. At the same time, an open loop and a closed loop are constructed, respectively, to investigate the necessity of recovering cold energy of boil-off gas. The results suggest recommendation of open loop system with nitrogen precooling.

The performance of nitrate-reducing Fe(II) oxidation processes under variable initial Fe/N ratios: The fate of nitrogen and iron species

The Fe/N ratio is an important control on nitrate-reducing Fe(II) oxidation processes that occur both in the aquatic environment and in wastewater treatment systems. The response of nitrate reduction, Fe oxidation, and mineral production to different initial Fe/N molar ratios in the presence of Paracoccus denitrificans was investigated in 132 h incubation experiments. A decrease in the nitrate reduction rate at 12 h occurred as the Fe/N ratio increased. Accumulated nitrite concentration at Fe/N ratios of 2–10 peaked at 12–84 h, and then decreased continuously to less than 0.1 mmol/L at the end of incubation. N2O emission was promoted by high Fe/N ratios. Maximum production of N2 occurred at a Fe/N ratio of 6, in parallel with the highest mole proportion of N2 resulting from the reduction of nitrate (81.2%). XRD analysis and sequential extraction demonstrated that the main Fe minerals obtained from Fe(II) oxidation were easily reducible oxides such as ferrihydrite (at Fe/N ratios of 1–2), and easily reducible oxides and reducible oxides (at Fe/N ratios of 3–10). The results suggest that Fe/N ratio potentially plays a critical role in regulating N2, N2O emissions and Fe mineral formation in nitrate-reducing Fe (II) oxidation processes.

Undernutrition shifted colonic fermentation and digest-associated bacterial communities in pregnant ewes.

The objective of this study was to evaluate the effect of undernutrition on colonic microbiota and fermentation in pregnant ewes. Sixteen ewes bearing multiple fetuses for 115days in the control (CON) and severe feed restriction (SFR) groups were fed 100% and 30% level of ad libitum feed intake, respectively. After 15-day treatment, all ewes were sacrificed to collect colonic digesta samples to extract DNA for 16S rRNA sequencing and to detect fermentation parameters. Our data showed that SFR increased (P < 0.05) the levels of colonic propionate, isobutyrate, butyrate, isovalerate, and valerate, and slightly decreased (P < 0.1) colonic pH. The mole proportions of isobutyrate, butyrate, and isovalerate were increased (P < 0.05) upon SFR while that of acetate was decreased (P < 0.05). Hematoxylin-eosin staining sections exhibited the disorderly, irregular, and loose arrangement and part sloughing of colonic epithelial cells. Furthermore, SFR decreased (P < 0.05) the diversity of colonic microbiota and changed the microbial communities. At the genus level, SFR increased (P < 0.05) the abundance of unclassified Peptococcaceae and decreased (P < 0.05) the abundances of Ruminococcus, unclassified Ruminococcaceae, and unclassified VadinBB60. Additionally, the abundances of Ruminococcus and unclassified Ruminococcaceae were positively correlated (P < 0.05) with the acetate proportion while the abundance of unclassified Peptococcaceae was negatively correlated (P < 0.05) with the percentages of isobutyrate, butyrate, and isovalerate. In summary, SFR diminished the diversity of bacteria, affected the composition of bacterial communities, and finally changed the colonic fermentation pattern and epithelial histomorphology in pregnant ewes. KEY POINTS: • Undernutrition changed colonic bacterial diversity and composition in pregnant ewes. • Microbial alteration affected colonic fermentation pattern and parameters. • Alteration of colonic microbiota and fermentation damaged epithelium histomorphology. Graphical abstract.

Cyanobacterial production of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) from carbon dioxide or a single organic substrate: improved polymer elongation with an extremely high 3-hydroxyvalerate mole proportion

The bioplastic poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) changes material properties upon altering mole ratio (mol%) of the two monomers: 3-hydroxybutyrate (HB) and 3-hydroxyvalerate (HV). Biotechnology for producing PHBV with a wide range of HV mol% using low amount of organic substrate is required. Here, 20 evolutionarily divergent cyanobacteria were examined for PHBV production. Under photoautotrophy with carbon dioxide (CO2) supply, one strain produced PHBV. But under heterotrophy using a medium containing only one type of organic substrate, 4, 15, and 13 strains were found to accumulate PHBV when supplied with acetate (C2H3O2), propionate (C3H5O2), and valerate (C5H9O2), respectively. Hence, these cyanobacterial PHBV productions required only CO2 or a single type of organic substrate. The obtained PHBV showed a broad range of HV mole ratios from 4 to 96 mol%. The cells producing PHBV with high HV mole ratios (31–96 mol%) exhibited low cellular acetyl-CoA levels. The PHBV with a 96.2 mol% HV and 3.8 mol% HB from Nostoc microscopicum elongated at 98 ± 15% (length/length), a 19.6-fold higher elongation than that of commercial poly-3-hydroxybutyrate containing 100 mol% HB. The results demonstrated the economical utility of cyanobacterial conversion of CO2 and a single organic substrate to synthesize PHBV with improved elongation quality.

Calculating biotite formula from electron microprobe analysis data using a machine learning method based on principal components regression

We present a new machine learning method for calculating biotite (sensu lato) structural formula from electron microprobe analysis (EMPA) data, which is based on principal components regression (PCR) of a dataset consisting of 155 fully analyzed biotite references that have chemistry and crystal structure refinement. The dataset is randomly grouped into a training set (75% in amount) and a test set (25% in amount). The training set is used to implement the structural formula and the test set is used to evaluate the performance of the model. The resulting linear regression coefficient matrix is then applied to calculate mole proportions of cations and anions of biotite samples using their compositional data from EMPA. Through this method, the distribution of the different cations and anions in the different sites can be calculated, including the tetrahedral Fe3+, octahedral Fe2+, octahedral Fe3+, OH and WO2− at the O(4) site. The O(4) site is assumed to be occupied by anions with a relation of 2 = F + Cl + OH + WO2−. Octahedral and interlayer vacancies could also be estimated in this model. The prediction quality for major elements is perfect with R2 > 0.95. The absolute errors in the estimated octahedral Fe2+, octahedral Al and OH at O(4) site are determined to be ±0.2 apfu (atom per formula unit based on 11O + 2(F, Cl, OH, O)), while those in total Fe3+ and WO2− at O(4) site are approximately ±0.3 apfu. A funnel-shaped relationship between absolute error in Fe3+/ΣFe ratio and FeOT wt% is observed, with the majority falling in the range of ±20%. Compared to previous normalization schemes, our model shows significant improvements in estimating Fe3+/ΣFe and WO2− at O(4) site. Our model is capable for calculating mineral formulae of common igneous and hydrothermal biotites, but not suitable for those that have been modified in a post-formation oxidation or reduction process. A supplementary Excel spreadsheet is provided that can be easily used for performing calculation from EMPA data.

Synthesis and characterization of processable aromatic poly(ether ether ketone amide)s modified by phenoxy and 1,3 ketone moiety linkages

New series of aromatic poly(ether ether ketone amide)s were synthesized by low-temperature solution polymerization of novel aromatic diamine, namely 1,3-bis-4′-(4″-aminophenoxy benzoyl)benzene (XIV), and aromatic diacid chlorides, viz. isophthaloyl chloride (IPC) and terephthaloyl chloride (TPC). Co-poly(ether ether ketone amide)s were also synthesized by employing various mole proportions of IPC and TPC with diamine (XIV). These poly(ether ether ketone amide)s were characterized by FTIR, solubility, inherent viscosity, TGA, DSC, and XRD. Inherent viscosities of these poly(ether ether ketone amide)s were in the range of 0.41–0.52 dL/g in DMAc, indicating the formation of moderate to high molecular weight of polymers. Poly(ether ether ketone amide)s showed good solubility in polar aprotic solvents such as N,N-dimethyl acetamide (DMAc), N-methyl 2-pyrrolidone, N,N-dimethylformamide, and dimethyl sulfoxide. These poly(ether ether ketone amide)s had glass transition temperatures, as determined by DSC, in the range of 252–302 °C. These polymers showed similar decomposition patterns and had no weight loss below 335 °C, and temperatures for 10% weight loss (T10) were in the range of 397–406 °C, indicating that these polymers showed good thermal stability.

Soluble aromatic polyamides modified by incorporation of 1,2,4-triazole and pentadecyl units into the backbone of polymer

A new series of soluble aromatic polyamides was synthesized by low temperature solution polycondensation of novel aromatic diamine namely 3,5-bis-(4′-amino phenyl)-4-(4″-methoxy-2″-pentadecyl phenyl) 1,2,4-triazole (VII) with aromatic diacid chlorides, viz. isophthaloyl chloride (IPC) and terephthaloyl chloride (TPC). The aromaticdiamine (VII) was characterized by elemental analysis, FT-IR, NMR (1H, 13C), and mass spectrometry. Copolyamides were also synthesized by employing various mole proportions of IPC and TPC with diamine (VII). Inherent viscosities of these polyamides were in the range of 0.50–0.65 dL/g in DMAc, indicating formation of moderate to high molecular weight of polyamides. These polyamides showed good solubility in polar aprotic solvents such as N,N-Dimethyl acetamide (DMAc), N-Methyl 2-pyrrolidone (NMP), N, N, Dimethyl formamide (DMF), and Dimethyl sulphoxide (DMSO), which may be due to incorporation of pendant methoxyphenyl moiety with pentadecyl units. The amorphous morphology of polyamides as evidenced by XRD. These polyamides had lower glass transition temperatures; as determined by DSC, compared to the Tg of conventional aromatic polyamides due to internal plasticization effect of long alkyl pentadecyl group. Polymers showed good thermal stability, with initial decomposition temperature above 300 °C.