Terephthaloyl Chloride Research Articles

ELECTRICAL CHARACTERIZATION OF METAL JUNCTION FORMED WITH PURE AND POLYANILINE-BLENDED POLY(SCHIFF BASE) POLYMER

In this paper, we demonstrate the formation of Schottky contact formed by Al with a new class of synthesized conjugated pure poly(Schiff base) (PSB) and its blend with varied concentrations of polyaniline (PANI). The Schottky behavior was transformed into Ohmic in the blended polymer. PSB was synthesized from the solution of polycondensation of terephthaloyl chloride (T) and 4-(4-hydroxybenzylideneamino)phenol (SB). The polymer showed good thermal stability with [Formula: see text] of 312∘C as determined by thermal gravimetric analysis–differential scanning calorimetry TGA–DSC and high molecular weight [Formula: see text] (g/mol) with coiled conformation as determined by laser light scattering. PBS was blended with various weight percentage ratios of PANI (0, 3, 6, 9, 12, 15 percent by weight of the pristine polymer). The metal contact (Au) was formed and studied in the temperature range of 293–373[Formula: see text]K, which showed that Schottky behavior in the intrinsic polymer with an ideality factor was close to 2 and then reduced to 1.0–1.2 in the blended polymers. In blended polymers, the conduction across the junction was characterized by Schottky emission at low field and Poole–Frenkel emission at high field. The Schottky barrier height showed a small increase with temperature, which was attributed to reduction in the built up of image charge. The Schottky and Poole–Frenkel emission coefficients were also determined and Schottky emission coefficient agreed with the theoretical value, while Poole–Frenkel emission coefficient was small. In short, the metal–semiconductor junction was affected by the blending, while conduction within the polymer remained independent of PANI concentration.

Design, Synthesis and Molecular Docking Studies of Novel Cyclic Pentapeptides Based on Phthaloyl Chloride with Expected Anticancer Activity

A series of Nα-phthaloyl bridged cyclic pentapeptide derivatives were synthesized and characterized on the basis of spectral and elemental analyses. A preliminary cytotoxicity evaluation of all novel compounds was carried out against four human cancer cell lines, human lung (A-549), colon (CaCo-2), prostate (PC-3) and breast (MCF-7) cancer cells at 100 μM concentration using MTT growth inhibition assay. Compound 3 gave the highest cytotoxic activity towards the human colon (CaCo-2) cancer cell line (Growth Inhibition = 72.4 %). Further molecular docking of the promising derivative 3 was developed to study its binding mode within the active site of EGFR enzyme. The docking results suggest good fitting through different hydrogen bond interactions with the protein residues to elicit anticancer activity

A complete description on effect of β-cyclodextrin-ester as a bio-based additive for preparation of safe PVC: From synthesis to computational study

Due to existing additive in the PVC product in some crucial fields for example, toys and biomedical devices, migration of Di-2-ethylhexyl phthalate (DEHP) can be hazardous to human health. Therfore migration of DEHP has caused a wide concern and this problem must be solved. In the present study, a water-insoluble β-cyclodextrin-ester (β -CDPN) was synthesized by reaction of β-cyclodextrin with terephthaloyl chloride as a cross-linker using micro-emulsion method. The β -CDPN loading DEHP was introduced to Polyvinyl chloride (PVC) as an active inhibitor to reduce DEHP migration. DEHP migration was determined using the UV–vis spectroscopy. It was found that the addition of β -CDPN can decrease the levels of DEHP migration from the tree component sample containing β -CDPN by almost 57 % as compare with PVC-DEHP sample. Also the anti-migration efficiency results showed improvement about 57.19 %. Mechanical properties of β -CDPN and DEHP including the tensile strength (TS), Young’s modulus (YM) and elongation at break (EB) were investigated. The results of mechanical properties indicated that all the mechanical data in this samples were slightly improved in the presence of β -CDPN by loading DEHP as compare to the PVC/DEHP system. The PVC films containing 2.4 mass% of β –CDPN showed the increasing in tensile strength (13 %), Young’s modulus (6 %) and elongation at break (7.2 %) values as compare to the PVC/DEHP. Also, computational method was used to investigate the inclusion complex of DEHP and β -CDPN and also inclusion shape and orientation. Based on the obtained results, it can be suggested that the most energetically favorable structure is in the form that aromatic group of DEHP enters into the cavity of β -CDPN through its wide rim. Altogether the results showed that the synthesized β -CDPN has large potential as green inhibitor to reduce DEHP migration. This could be a promising option to overcome the environmental problems caused by DEHP plasticizer.

Polyarylate membrane constructed from porous organic cage for high-performance organic solvent nanofiltration

Preparation of highly permeable and selective organic solvent nanofiltration (OSN) membranes is desired for precise chemical separations. Although the emerging nanomaterials and novel preparation methods have significantly boosted the membrane performance, it still requires much effort to drive them toward scale-up production with lower cost and easier preparation process. Herein, we constructed a polyarylate membrane from one kind of porous organic cage, namely Noria through traditional interfacial polymerization technique. Under the catalysis of triethylamine, Noria in aqueous phase would react with terephthaloyl chloride (TPC) in hexane to form a dense nano-film. The inner cavity of Noria molecule provided nano-channel for both polar and non-polar solvents to transport through the membrane. Specially, the Noria + TPC membrane exhibits a high permeance for methanol up to 18 L m−2h−1bar−1. This is resulted from the low interaction energy between methanol and Noria as revealed by the molecular dynamics (MD) simulation. In addition to the excellent performance, the simple preparation process with low-cost materials suggests the great potential of Noria + TPC membrane for practical application. Moreover, it would inspire the exploration of other molecules with tailored chemical structures for the assembly of high-performance membranes in future.

Improved wave-transparent performances and enhanced mechanical properties for fluoride-containing PBO precursor modified cyanate ester resins and their PBO fibers/cyanate ester composites

Poly(p-phenylene-2,6-benzobisoxazole) (PBO) fibers can be applied as reinforcement to fabricate PBO/cyanate ester (CE) resin laminated composites with light weight, high specific strength & modulus, excellent dielectric properties, and extraordinary excellent thermal & humidity resistance for radome application. However, the surface of PBO fibers is extremely inert, resulting in poor interfacial compatibility to CE matrix. Besides, the toughness and wave-transparent performances of the cured CE resins need to be further improved. In this work, 2, 2-bis(3-amino-4-hydroxyphenyl) hexafluoropropane (6FAP) and terephthaloyl chloride (TPC) were performed to synthesize fluorine-containing epoxy-terminated PBO precursor (epoxy-preFPBO) via condensation reaction followed by end-group functionalization with glycidol. Afterwards, epoxy-preFPBO modified CE resins (FPBO-co-BADCy resins) were prepared by copolymerization of epoxy-preFPBO and bisphenol A cyanate ester (BADCy). FPBO-co-BADCy resins with 7 wt% epoxy-preFPBO displayed the optimal wave-transparent performances and mechanical properties. Dielectric constant (ε) and dielectric loss (tanδ) is respectively 2.48 and 0.0081, and the corresponding transmittance (|T|2) at 10 MHz is 94.9%, higher than that of pure BADCy (92.7%). The corresponding flexural and impact strength was enhanced to 119.9 MPa and 12.3 kJ/m2, 21.4% and 24.5% higher than that of pure BADCy, respectively. In addition, FPBO-co-BADCy resins presented better interfacial bonding strength with PBO fibers than that of pure BADCy.

A new generation of star polymer: magnetic aromatic polyamides with unique microscopic flower morphology and in vitro hyperthermia of cancer therapy

In this work, a novel magnetic nanocomposite based on aromatic polyamide as a statistical star polymer was designed, characterized and studied in hyperthermia process of cancer therapy. The polymerization reaction was carried out via surface modification of magnetic nanoparticles (Fe3O4 MNPs) using polymerization process by phenylenediamine derivatives and terephthaloyl chloride. Various analytical techniques such as field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy, energy-dispersive X-ray, thermogravimetric and vibrating-sample magnetometer analyses were used to confirm the structure of the prepared nanocomposite. A unique rose flower and sphere morphologies were observed by FE-SEM images by the result of polymerization process and fabrication of the synthetic polymeric strands on the surface of the modified Fe3O4 magnetic cores. The application of this novel magnetic nanocomposite was evaluated in hyperthermia process as a potential method for cancer therapy and its exposure to an external alternating magnetic field. The highest specific absorption rate measured for 0.5 mg/mL of a sample was 191.97 w g−1, and the saturation magnetization value was 4.3 emu g−1.

Dynamic mechanical and fracture morphology of kevlar fiber filled groundnut reinforced epoxy composites

Abstract The present study deals with the synthesis and characterization of Kevlar fibers produced by a condensation reaction of para-phenylenediamine with terephthaloyl chloride. The composites were fabricatedusing a 5 % KFs fiber loading for groundnut/epoxy at varied filler loadings by means of hand lay-up. We have evaluated dynamic mechanical properties such as the tensile, flexural and impact strength ofgroundnut/epoxy composites reinforced with Kevlar fibers. All the dynamic mechanical properties were performed as per the essential American Society of Testing and Methods standards. The Groundnut/epoxy hybrid composite reinforced with synthesized Kevlar fibers has a high tensile, flexural and impact strength. A composite treated in this manner has high dynamic mechanical properties which make it suitable for a number of applications in engineering industries.

Synthesis of new poly-benzoylthiourea and thermal and surface properties

Two new benzoylthiourea polymers (BTP1/p1–3, BTP2/p2–3) were synthesized via reaction of substituted amines and terephthalodiisothiocyanate which is obtained by the reaction of terephthaloyl dichloride and potassium thiocyanate. As the phase transfer catalyst, poly(ethyleneglycol) dimethylether were tested. Substances 1HNMR,13CNMR, Elemental analysis were characterized. Thermal properties of obtained polymers (p1–3, p2–3) were examined by using TGA-DTG, DTA analysis. It was observed that p1–3 lost 100% of its mass around 750 °C, p2–3 lost 76.52% of its mass around 850 °C. p2–3 showed better thermal stability compared to p1–3. Surface properties of polymers were examined with SEM. Surface area of benzoylthiourea polymers was measured by using the BET. A BET surface areas of 14.280 m2/g and 12.691 m2/g and was found for p1–3 and p2–3 (300 K), respectively and total pore volumes are 2,77 × 10−1 cm3/g and 4,90 × 10−1 cm3/g. Degradation reactions, mass losses, melting and decomposition points were determined by analysing curves. The mercury retention properties of the insoluble polymeric p1–3, p2–3 were analyzed by equilibrium reactions. The synthesized polymers also act as high-impact sorbents/sensors in the removal of trace amounts of Hg2+. In this study, it was observed that ~99,7% mercury from environmental sources such as water can be removed with low amount of resin despite the moderate BET surface area (when the resin surface areas after the modification of inorganic and organic polymers with thiourea were examined). In addition, the new benzoylthiourea polymers can be synthesized in 100% high yield. This study proposes the versatility of microporous benzoylthiourea polymers targeting various environmental challenges for the separation and detection of toxic metals. Although the basic structure of these compounds is considered as chromophore, oxochrome groups, aromatic rings and resonance structures and their electronic properties, photoluminescence/electroluminescence radiations could not be determined because the substances did not dissolve.

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.

Synthesis and Performance Characteristics of Superstructure Polyethers

In this article, we describe the synthesis of polyretherketones (PEK) by the method of acceptor-catalytic polycondensation, using oligoketones with different condensation degree (n = 1, 10, 20), isophthalic and terephthalic acid dichloride hydrides and 2,2-di-(4-hydroxyphenyl)propane. Their properties were also studied

Synthesis of Porous Organic Polymers with Tunable Amine Loadings for CO2 Capture: Balanced Physisorption and Chemisorption.

The cross-coupling reaction of 1,3,5-triethynylbenzene with terephthaloyl chloride gives a novel ynone-linked porous organic polymer. Tethering alkyl amine species on the polymer induces chemisorption of CO2 as revealed by the studies of ex situ infrared spectroscopy. By tuning the amine loading content on the polymer, relatively high CO2 adsorption capacities, high CO2-over-N2 selectivity, and moderate isosteric heat (Qst) of adsorption of CO2 can be achieved. Such amine-modified polymers with balanced physisorption and chemisorption of CO2 are ideal sorbents for post-combustion capture of CO2 offering both high separation and high energy efficiencies.

Methods for the synthesis of dichloroanhydrides of phthalic acids

Dichloroanhydrides of isophthalic (isophthaloyl chloride) and terephthalic (terephthaloyl chloride) acids are, undoubtedly, strategically important compounds. Among their main application areas is synthesis of Aramid fibers to be used for manufacturing dual use materials including synthesis of Terlon®, Phenylon®, Armos®, Tegelen®, SVM®, and Rusar® fibers. Specific requirements for quality of the target anhydrides and feedstock determine the choice of the synthetic methods. In the review paper, various methods, including catalytic methods, for the synthesis of iso- and terephthaloyl chlorides based on the use of different types of feedstock are discussed. Main methods for analysis of these compounds are described in detail.

From Monomers to a Lasagna-like Aerogel Monolith: An Assembling Strategy for Aramid Nanofibers.

The manipulation of nanobuilding blocks into a 3D macroscopic monolith with ordered hierarchical structures has been much desired for broad and large-scale practical applications of nanoarchitectures. In this paper, we demonstrate a fully bottom-up strategy for the preparation of aramid aerogel monoliths. The process starts from the synthesis of poly(p-phenylene terephthalamide) (PPTA) through the polycondensation of p-phenylenediamine and terephthaloyl chloride, with the assistance of a nonreactive dispersing agent (polyethylene glycol dimethyl ether), which helps the dispersal of the as-synthesized PPTA in an aqueous medium for the formation of p-aramid nanofibers (ANF). Then the vacuum-assisted self-assembly (Vas) technique is skillfully connected with the ice-templated directional solidification (I) technique, and the combined VasI method successfully tailors the self-assembly of ANF to transform the 1D nanofibers into a 3D aerogel monolith with a specific long-range aligned, lasagna-like, multilaminated internal structure. The study of the aerogel microstructure revealed the dependence of the lamina orientation on the direction of the freezing front of ice crystals. This direction should be parallel to the deposition plane of the Vas process if a long-range aligned lamellar structure is desired. The anisotropy of the multilaminated aerogel was proven by the different results in the radial and axial directions in the compression and thermal conductivity tests. As a kind of organic aerogel, the ANF monolith has typical low density, high porosity, and low thermal conductivity. Additionally, the ANF monolith exhibits high compressive stress and excellent thermal stability. Considering its high performance and facile preparation process, potential applications of the ANF aerogel monolith can be expected.

Synthesis and Functionalization of Porous Zr-Diaminostilbenedicarboxylate Metal-Organic Framework for Storage and Stable Delivery of Ibuprofen.

A stable porous metal–organic framework (MOF), Zr-diaminostilbenedicarboxylate (Zr-DASDCA), was synthesized and modified with oxalyl chloride (OC) or terephthaloyl chloride (TC) to introduce various functional groups onto the Zr-DASDCA. Both pristine and functionalized Zr-DASDCAs, together with activated carbon, were used as a potential carrier for ibuprofen (IBU) storage and delivery. Zr-DASDCAs, especially the modified ones (OC-Zr-DASDCA and TC-Zr-DASDCA), showed competitive results in IBU delivery. Specifically, the release rate in phosphate-buffered saline solution at pH 7.4 was nearly constant (R2 ≈ 0.98) for up to 10 days, which would be very effective in IBU dosing to the human body. Moreover, the release rate could be controlled by changing the pH of the releasing solution. The rate of IBU release from both pristine and modified Zr-DASDCAs at pH 7.4 and 3.0 was also explained with a few interactions such as H-bonding and electrostatic repulsion, together with the relative pore size of the Zr-DASDCAs. Therefore, the results suggested that functionalization of MOFs via postsynthetic modification, especially with OC and TC, to introduce various functional groups onto MOFs is an effective approach to not only reducing the release rate of IBU but also inducing a constant release of IBU for as long as 10 days.

Pioneering Work on Catenanes, Rotaxanes, and a Knotane in the University of Freiburg 1958–1988

Research at the University of Freiburg is summarized which aimed at realizing catenanes, rotaxanes, and a molecular knot from 61–62 until 41 years ago. Taking a fresh view at ansa‐compounds – distinct from those in which he had been interested for other reasons before – Arthur Lüttringhaus began to tackle syntheses of catenanes in 1957. The first isolation of a pure catenane (37) succeeded in 1964 jointly with Gottfried Schill. Most of the progress made in the sequel was due to Schill alone or achieved under his direction; in addition, a few follow‐up studies were published without Schill or Lüttringhaus being their authors. The major feats of these endeavors were the syntheses of the following molecules: (1) the first catenanes (38 – de‐acetyl‐41, 74) without a ring in any constituent (this feature makes them unique till today; the catenane 74 holds the additional record of being the only all‐hydrocarbon catenane till now); the first [3]catenanes at all (obtained as a mixture of constitutional isomers C2v‐97 and C2h‐97); the first [3]catenanes exhibiting topological isomerism (89, iso‐89, and neo‐iso‐89); the rotaxanes 70 [which had the design peculiarity of being convertible into a catenane (74)], 113 (Schill's #1‐rotaxane), and 115; the pre‐knotane rac‐dia‐iso‐123 [provided it was obtained and not (only) its topological isomer dia‐iso‐123]. – For due perspectives, pertinent studies of third parties are included, too: 1) Wasserman's reports on the isolation of the catenane 8 are analyzed in great detail; the conclusion is that the identity of 8 was never established. 2) Schill's oscillating rotaxane 70 from 1988, which is subject to a reversible and non‐degenerate ring migration (→ iso‐70), is supplemented by Stoddart's much faster oscillating rotaxane 71 from 1991, which undergoes a reversible and degenerate ring migration (→ 71 instead of → iso‐71) and was dubbed “molecular shuttle”. 3) The first [3]catenanes from the groups of Schill (97; 1969), Sauvage (98 and 99; 1985), and Stoddart (100–102; 1991) are juxtaposed. 4) The Harrisons' synthesis of the rotaxane 106 by a most noteworthy solid‐phase approach (1967) is recalled in the context of Schill's synthesis of the rotaxane 113 (1967 or 1969). 5) Attempts at threading α‐cyclodextrin by long‐chain 1,ω‐dithiols (→ 130) and ring‐closing the latter oxidatively for obtaining catenated disulfides failed in Lüttringhaus' 1957/1958 studies; in contrast, Stoddart's threading permethyl‐β‐cyclodextrin (133) by the long‐chain 1,ω‐diamine 132 and ring‐closing the latter by a double condensation with terephthaloyl dichloride was successful by providing 3 % of the catenated bislactame 134 in 1993. The concluding section characterizes the synthetic strategies towards catenanes and rotaxanes developed in Freiburg as “template‐based”. This differs from the Nobel Prize Committee's assessment.

Trans와 Cis-1,4-Cyclohexanedimethanol, Terephthaloyl Dichloride, 그리고 2,6-Naphthalenedicarboxylic Chloride로부터 합성된 폴리에스테르 공중합체의 단일 단계 용액 중합과 열적 특성

Trans와 Cis-1,4-Cyclohexanedimethanol, Terephthaloyl Dichloride, 그리고 2,6-Naphthalenedicarboxylic Chloride로부터 합성된 폴리에스테르 공중합체의 단일 단계 용액 중합과 열적 특성

Schottky Diodes Based on the New Chitin Derivatives

New chitin derivatives were synthesized by the reactions of chitin with o-acetylsalicyloyl chloride and phthaloyl chloride and their structure was characterized by FTIR and 13C CP-MAS solid-state NMR spectroscopy and X-ray powder diffraction technique. Also, the thermal and surface properties of the chitin derivatives were investigated by thermogravimetric analysis and a scanning electron microscope. In addition, some electrical properties of the polymers were determined using Hall effect technique. Then, the Schottky diodes were fabricated by the formation of interlayers of chitin derivatives between Au metal and n-Si semiconductor, and the electrical and photoelectrical properties of the diodes were determined.

Prediction of PEKK properties related to crystallization by molecular dynamics simulations with a united-atom model

Semicrystalline polyetherketoneketone (PEKK) is widely used as the matrix in carbon-fiber composites. Understanding and predicting the crystallization thermodynamics and kinetics of this class of polymers is, thus, of great interest. This paper uses molecular dynamic (MD) simulations using Dreiding united-atom (UA) potentials to characterize a wide range of thermos-physical properties of PEKK. We characterized the effect of terephthaloyl chloride to isophthaloyl chloride (T/I) on an extensive set of properties, including the lattice parameters and stability of PEKK crystal structures, glass transition temperature, melting temperature, crystal/amorphous interfacial energy, and enthalpy of fusion. We find good overall agreement between predicted properties and experimental values and the simulations help clarify inconsistencies in the literature. In combination with classical nucleation theory, nucleation barriers and critical nucleus size at different temperature are predicted.

Formamide Catalysis Facilitates the Transformation of Aldehydes into Geminal Dichlorides

Herein, a novel method for the transformation of aldehydes into geminal dichlorides based on phthaloyl chloride as reagent and N-formylpyrrolidine as Lewis base catalyst is disclosed. Given the mild reaction conditions, the current protocol is distinguished by high levels of functional group compatibility and scalability and is operationally simple. The in situ formation of a Vilsmeier Haack reagent type intermediate is likely to be essential for this organocatalytic nucleophilic substitution reaction.

Aromatic polyesters containing pendant azido groups: Synthesis, characterization, chemical modification and thermal cross-linking

A partially bio-based bisphenol containing pendant azido group viz., 4,4′-(5-azidopentane-2,2-diyl) diphenol (AZBPA) was synthesized starting from 4,4′-bis (4-hydroxyphenyl) pentanoic acid. AZBPA was reacted with isophthaloyl chloride (IPC), terephthaloyl chloride (TPC) and a mixture of IPC/TPC (50:50 mol%) by phase transfer-catalyzed interfacial polycondensation route to obtain aromatic polyesters containing pendant azido groups. Copolyesters containing pendant azido groups were also synthesized by polycondensation of different molar proportions of AZBPA and commercially available 4,4′-(1-phenylethane-1,1-diyl) diphenol (BPA-AP) with IPC. Inherent viscosities and number average molecular weights of (co)polyesters were in the range 0.85–1.64 dL/g and 58,900–190,400, respectively, indicating the formation of reasonably high molecular weight polymers. Tough, transparent, and flexible films could be cast from chloroform solutions of these polyesters. X-Ray diffraction analysis showed that (co)polyesters were amorphous in nature. (Co)polyesters were characterized using FT-IR, 1H NMR spectroscopy, XRD, TGA and DSC analysis. The chemical modification of a representative copolyester containing pendant azido groups was carried out quantitatively using copper-catalyzed azide-alkyne cycloaddition (CuAAC) with two alkynes viz., phenyl acetylene (PA) and ethynyl-4-nitrobenzene (ENB). Additionally, (co)polyesters containing pendant azido groups were thermally cross-linked (170 °C/12 h) leading to the formation of network structures based on azide to nitrene decomposition and subsequent reactions on polyester backbone. The selected cross-linked polyesters were characterized by stress-strain measurements. The cross-linked polymers exhibited higher tensile strength and Young’s modulus and lower % elongation at break compared to corresponding pristine polyesters containing pendant azido groups.