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The progressive development of lightweight composites exhibiting desirable thermo‐mechanical properties is an area of growing interest, particularly with the phthalonitrile (PN) based composites, which have shown great potential. However, our understanding of the mechanical and thermal properties of the phenol‐containing phthalonitrile (PN75) resin composites often reveals limitations that make them less suitable for specific structural applications. In this work, we focused on enhancing the mechanical and thermal properties of the PN75 resin through the incorporation of the 4‐aminophthalonitrile (4‐APN), resulting in improved the curing behaviors and increased thermal stability. Our investigation of the short carbon fiber (SCF) and short glass fiber (SGF) reinforced PN75 resin composites revealed that the hybrid SCF/SGF‐based composites at 15 wt% SCF and 15 wt% SGF content exhibited an excellent tensile and the flexural strength. Additionally, the thermogravimetric analysis demonstrated maximum onset degradation and decomposition temperatures at this ratio compared with the neat resin, also we evaluated the interfacial adhesion properties of the SCF/SGF and the PN75 resin composites. These findings contribute to the advancement of polymer composite materials and expand their potential applications across various industries. [ABSTRACT FROM AUTHOR]

Simple synthesis and high performance are eternal pursuit for polymers. To lower the curing temperature, lower the melt viscosity and improve the processability of high performance phthalonitrile resins, a solvent‐free method was applied to synthesize three from different phenols. Their chemical structure was confirmed by FTIR and NMR spectra, the curing behavior was investigated by DSC and rheology. It was found that the polymerization of phthalonitrile groups could be effectively promoted by benzoxazine moieties and the curing temperature of phthalonitrile groups dropped to around 240°C. Consequently, owing to the high curing reactivity, polymers obtained at relatively low curing temperature possessed high crosslinking density and extremely high thermal stability. P‐apn‐200, which was cured at 200°C, showed 5 wt% weightloss temperature (Td5) of 472°C and char yield (Yc) of 75.77% at 800°C. Moreover, the polymers obtained after curing at 280°C showed superior dimensional stability, CN‐apn‐280 showed extremely low linear expansion coefficient (CTE) of 10.7 ppm/°C. And mP‐apn‐280 showed HR capacity of 3.99 J/g‧K, peak HRR of 4.0 W/K and total HR of 0.8 kJ/g. [ABSTRACT FROM AUTHOR]

A low-cost fully dicyclopentadiene (DCPD)-networked epoxy system was designed. Compared to commercial diglycidyl ether of bisphenol-A epoxy resin counterparts, the cured DCPD-based resin demonstrates excellent thermal properties (Tg > 250 °C) and a low dissipation factor (0.0065 at 10 GHz), indicating its potential as a promising thermoset for high-performance electronic applications. [ABSTRACT FROM AUTHOR]

Herein, a novel approach was developed for the introduction of stabilizing compounds into polymers through a pre-impregnation process prior to processing, which is expected to improve their dispersion and, consequently, increase their efficacy. Ethylene-norbornene copolymer (EN) pellets were impregnated with quercetin or rutin in ethanol or a mixture of solvents (ethanol-dioxane (3:1)) for 24 h. Then, EN-based samples containing impregnated pellets were manufactured using a laboratory extruder. The research demonstrated that the materials containing impregnated pellets exhibited improved thermo-oxidation resistance, higher antibacterial effect (the number of dead cells increased from 8 to 59%), and satisfactory photostability. This may be a direct result of their better dispersion degree and their more gradual, controlled release from the EN during operation. If we compare the stabilizing effect of both polyphenols, quercetin was more efficient, which may be attributed to the presence of hydroxyl group at the C3 position in the C ring, which could increase the reactivity of the catechol structure of the B ring. The proposed approach effectively solves the issues that arise during the commonly used processing techniques and may facilitate the broader utilization of natural stabilizers in the polymer industry. [ABSTRACT FROM AUTHOR]

Phthalontirile resins are renowned as the most heat‐resistant polymeric materials and exhibit exceptional performance under harsh conditions. Consequently, phthalonitrile thermosets offer the potential to substitute metals in hot parts, thereby broadening the operational limits of plastic materials in high‐tech applications. Given their unique combination of properties, phthalonitriles have garnered significant demand across sectors such as aerospace, automotive, electronics, and renewable energy. With industrial production and application of phthalonitriles recently initiated in several countries, questions regarding the sustainability of these materials have naturally arisen. Thermosetting materials, owing to their highly cross‐linked architecture, cannot be recycled, necessitating the adoption of synthetic methods utilizing bio‐feedstock raw materials and green protocols to mitigate their environmental impact. The present prospective review summarizes and analyzes the current state‐of‐the‐art in bio‐based phthalonitrile resins and discusses potential directions for research and development of new application areas, with a focus on the challenge of maintaining high‐performance levels during the transition to bio‐based raw materials. [ABSTRACT FROM AUTHOR]

Diglycidyl ether of bisphenol A crosslinking with glutaric anhydride is used to form the conventional "covalent adaptive network", polyether sulfone (PES) by coiling and aggregating on the adaptive network is used to significantly increase the uncured resin viscosity for improving the processability of epoxy resin, but inevitably affecting the curing reaction and dynamic transesterification reaction. This study investigates the crucial roles of PES in curing dynamics and stress relaxation behavior. The results indicate that although PES does not directly participate in the crosslinking reaction of polyester‐based epoxy vitrimers. Moreover, the isothermal curing studies reveal that the addition of PES can greatly bring forward the reaction rate peak from conversion α = 0.6 to α = 0.2, meaning that the curing mechanism transfers from chemical control to diffusion control. Dynamic property analysis shows that the addition of PES significantly accelerates stress relaxation, especially at lower temperatures, leading to low viscous flow activation energy Eτ and relatively insensitive stress relaxation behavior to temperature. Introducing PES into vitrimer resin greatly improves crosslinking density (2.31 × 10⁴ mol m−3), enhancing glass transition temperature (82.68 °C), tensile strength (68.66 MPa), and fracture toughness (6.25%). Additionally, the modified vitrimer resin exhibits satisfying shape memory performance and reprocessing capability. [ABSTRACT FROM AUTHOR]

The renewable and biosynthetic molecule, vanillin, was used in the preparation of a new phthalonitrile resin (PN), containing two phthalonitrile groups without pre‐modification of the vanillin structure. This PN resin was characterized thoroughly by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), nuclear magnetic resonance (NMR) spectroscopy, rheometry, Fourier transform infrared spectroscopy (FTIR), and single‐crystal X‐ray diffraction (XRD). The monomer exhibited excellent rheometric viscosities below 250 cP at processing temperatures and a good pot life. After complete curing, the PN polymer exhibited thermal stability above 500°C, a glass transition temperature (Tg) above the final postcure temperature of 380°C, and exceptional retention of structural integrity. These results highlight a vanillin‐derived PN resin is an excellent candidate for a variety of applications where high temperature and mechanical stability over a large temperature range are required. [ABSTRACT FROM AUTHOR]

ABSTRACT To explore the room‐temperature synthesis of metal phthalocyanines with unsaturated substituents, two zinc phthalocyanines with unsaturated alkoxy groups were synthesized in a reaction system composed of 4‐citronellol‐oxy‐phthalonitrile or 4‐geraniol‐oxy‐phthalonitrile, Zn(OAc)2⋅2H2O, DBU, and ethanol, at room temperature. The synthetic reactions lasted for 7 days and the yields of two phthalocyanine derivatives reached 21% and 18%, respectively, and they are inclined to protonation in a non‐coordinated organic solvent, for example, CHCl3. By the way, the phthalocyanine compounds with other metals, such as Cu, Ni, and Co, cannot be prepared. This work will provide preference for improving the synthetic method in the future, so as to synthesize many new phthalocyanine compounds in general laboratories. [ABSTRACT FROM AUTHOR]

Phthalonitrile monomer containing oxazine ring (BPS‐Ph) was synthesized using bisphenol‐S, aniline, paraformaldehyde, and 4‐nitrophthalonitrile via a two‐step method. The differential scanning calorimetry (DSC) data of the curing process of BPS‐Ph monomer indicates that the peak polymerization temperature of the cyan group is about 250°C and that confirms the promoting effect of oxazine ring on the curing reaction of phthalonitrile. The rheological data of E51/DDS containing BPS‐Ph indicates that the BPS‐Ph monomer also has promoting effect on the curing process. The activation energy was studied via the iso‐conversional method principle. The activation energy corresponding to the E51/DDS crosslinking reaction is 75.79 and 60.54 kJ mol−1, respectively, for pure E51/DDS and E51/DDS/BPS‐Ph. Moreover, the activation energy of the crosslinking of phthalhydrazine is 74.1 kJ mol−1 which is rather lower than that in pure BPS‐Ph, and that implies the synergistically catalytic effect of the oxazine ring and the amine. The addition of BPS‐Ph monomer significantly improves the thermal behaviors of the thermoset. The char yield in N2 atmosphere increased from 15.6% to 53.9% when adding 30% BPS‐Ph to the E51/DDS. Moreover, the peak weight loss temperature decreased from 407 to 385°C. The phase separation size of poly‐BPS‐Ph in E51/DDS is about tens to hundreds nanometers according to the atomic force microscopy (AFM) phase diagram. It is indicated that incorporation of phthalonitrile monomer containing oxazine ring into epoxy/amine system is an applicable and effective way to promote the thermal behavior of the thermoset. [ABSTRACT FROM AUTHOR]

Preparation of high-performance thermosetting resins via bio-based resources is important for the development of a sustainable world. In this work, we proposed the introduction of cyanide structure groups into the molecular structure of epoxy resins to give them excellent heat resistance. A eugenol-based epoxy-phthalonitrile (EEPN) resin was synthesized by a two-step process using the bio-based renewable resource of eugenol, and a series of EEPN/Epoxide resin (E51) blend resins with different EEPN contents were prepared. The structure of the EEPN monomer was characterized and confirmed by Fourier transform infrared (FTIR), nuclear magnetic resonance (NMR), and elemental analysis. The thermal stability and dynamic mechanical properties of the cured resins were investigated by thermogravimetric analysis and dynamic mechanical thermal analysis. The experimental results showed that EEPN had excellent heat resistance; the char yield at 800 °C was 67.9 wt%, which was much higher than that of E51 at 26.3 wt%; and the heat resistance of the blended resins was significantly improved with the increase in the EEPN content. [ABSTRACT FROM AUTHOR]

Alzheimer's disease, is one of the irreversible neurodegenerative disorders among older people, causes behavior, memory, and thinking problems. This study aim is to synthesize of 4‐({8‐[3‐(dimethylamino)phenoxy]octyl}oxy)phthalonitrile, zinc(II) phthalocyanine and its water soluble derivative containing ({8‐[3‐(dimethylamino)phenoxy]octyl}oxy) substituents at the peripheral positions first time. To determine the potential of water soluble silicon(IV) and zinc(II) phthalocyanines for use in AD, spectrophotometric assays were performed to determine their acetylcholinesterase/butyrylcholinesterase inhibitory effects. In addition, their DNA nuclease properties were evaluated by agarose gel electrophoresis. The results showed that the compounds inhibited acetylcholinesterase/butyrylcholinesterase. They did not damage pBR322 plasmid DNA depending on time and concentration. As a result of the experiments, it is revealed that the compounds may be the potential for use as cholinesterase inhibitors, which is a promising approach for the treatment of Alzheimer's disease. [ABSTRACT FROM AUTHOR]

In this study, new peripherally substituted symmetric zinc and magnesium phthalocyanines (4 and 5) were successfully prepared by cyclotetramerization of the tetrahydropyrimidone (THPM)-linked phthalonitrile 3. The identity of the compounds were confirmed primarily through spectroscopic analysis including NMR, FT-IR, UV-Vis and MALDI-TOF mass spectroscopy. The photophysical and photochemical properties of the synthesized phthalocyanines (Pcs) were examined using UV–Vis absorption and fluorescence emission spectroscopy techniques. The quantum yields of singlet oxygen were found to be 0.50 and 0.33 for compounds 4 and 5 in DMSO, respectively. In addition to photo-physicochemical properties, the enhanced biological activities of compounds 4 and 5 were investigated using a range of biological assays, namely, antibiofilm, microbial cell viability, antioxidant, DNA cleavage, antimicrobial and photodynamic antimicrobial assays. The maximum DPPH inhibition of 4 and 5 was detected as 40.46% and 25.76% at 100 mg L−1, respectively. Fragmentation of the DNA molecule was observed at concentrations of 25 mg L−1, 50 mg L−1 and 100 mg L−1 for 4 and 5. Additionally, effective inhibition of microbial cell viability was observed with the targeted Pcs. The antibiofilm properties of these compounds were found to be concentration-dependent. The biofilm inhibition activities of 4 and 5 were found to be 96.01% and 92.04% for S. aureus, while they were 95.42% and 91.27%, for P. aeruginosa, respectively. The antimicrobial activities of 4 and 5 on different microorganisms were evaluated using the microdilution assay. In the case of photodynamic antimicrobial treatment, the newly synthesized Pcs showed more effective antimicrobial inhibition compared to the control. These findings suggest that compounds 4 and 5 can be used as promising photodynamic antimicrobial agents for the treatment of many diseases, particularly infectious diseases. [ABSTRACT FROM AUTHOR]

Quercetin (Q), one of the most abundant molecules in nature, remains relatively unexplored in the realm of bio-based thermosets. In line with the pursuit of sustainability, we report the successful synthesis of a novel bio-based phthalonitrile (PN) monomer (Q-Ph) using Q. The synthesis involved a nitro displacement reaction with 4-nitrophthalonitrile (4-NPN). Confirmation of the monomer's structure utilized hydrogen and carbon nuclear magnetic resonances (1H and 13C NMR), Fourier transform infrared spectra (FTIR), and elemental analysis. Curing characteristics were examined by differential scanning calorimetry (DSC), and polymerization was analyzed using FTIR. The resulting monomers showed a wide processing window and low melt viscosity via rheological analysis. Thermal and thermomechanical properties were assessed using dynamic mechanical analyzer (DMA) and thermogravimetric analysis (TGA), revealing lower curing and polymerization temperatures compared to petroleum-based counterparts. The synthesized resin achieved a high Tg exceeding 400°C, a char yield of 79% at 1000°C, and T5% and T10% values of 564 and 660°C, respectively. The Q-Ph polymer demonstrated superior performance, with evidence of an autocatalytic curing mechanism. These results highlight quercetin as a promising petrochemical replacement for the preparation of self-curable PN thermosets, especially for high-performance applications. [ABSTRACT FROM AUTHOR]

The disadvantage of poor thermal performance of epoxy resin limits its application in special fields, therefore we improve the thermal performance of epoxy resin by copolymerizing it with phthalonitrile resin. A novel self-promoted curing phthalonitrile monomer containing pyridine rings and amino groups (APNH) was successfully synthesized using 2-amino-4-hydroxypyridine and 4-nitrophthalonitril, and characterized by FTIR and NMR spectra. DSC confirmed that the APNH monomer exhibits curing behavior that is self-promoting. Copolymerizing the APNH monomer with epoxy resin enhances the thermal performance of the epoxy resin. The curing behavior of the EPNH copolymer was studied using DSC, which revealed two distinct curing peaks. FTIR analysis showed that the EPNH copolymer has formed structures such as triazine, phthalocyanine, and isoindoline. The presence of cyano groups significantly enhances the thermal properties of the copolymer, surpassing those of traditional epoxy resins. This enhancement in thermal performance amplifies with an increase in the content of the APNH monomer. The research indicates that the EPNH copolymer exhibits superior thermal stability and elevated glass transition temperatures, facilitating the application of epoxy resin in specialized areas. [ABSTRACT FROM AUTHOR]

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The bisphenol A-type phthalonitrile (BAPH) was blended with the classic epoxy system E51/DDS to prepare the epoxy/phthalonitrile thermoset. The curing kinetics were investigated by differential scanning calorimetry (DSC) using the isoconversional principle, and the average activation energy (Eα) of the E51/DDS curing reaction was found to decrease from 87 kJ/mol to 68.6 kJ/mol. Combining the results of the rheological study, the promoting effect of phthalonitrile on the crosslink of epoxy/amine is confirmed. The curing reaction of the blended resin was characterized using FTIR, and the results showed that BAPH could react with DDS. The thermal behaviors of the thermosets were investigated via DMA and TGA. The glass transition temperature (Tg) is found to increase from 181 °C to 195 °C. The char yield increases from 16% to 59.6% at 800 °C in a N2 atmosphere, which is higher than the calculated value based on the proportional principle. The AFM phase images show that there is no phase separation in the cured thermoset. The results imply that the cured epoxy/amine/phthalonitrile blend is probably a kind of copolymer. The real-time TG-MS indicated that the pyrolysis of the thermoset can be divided into two relatively independent stages, which can be assigned to the cleavage of the E51/DDS network, and the phthalocyanine/triazine/isoindoline, respectively. [ABSTRACT FROM AUTHOR]

This study aims to analyze the degradation behavior and mechanisms of amine-cured epoxy asphalt (EA) under the combined effects of ultraviolet (UV) radiation, oxygen, and temperature. To achieve this, amine-cured epoxy resin (ER) and EAs containing 35%, 45%, and 55% asphalt content were prepared and subjected to simulated UV-based aging. Various analytical techniques were employed to investigate the mechanical properties, microstructure, morphology, and oxidation layer of ER and EAs. The results indicate that after UV-based aging, ER and EAs with 35%–45% asphalt content experienced an increase in mass, a decrease in strength and glass transition temperature. In comparison, EAs with 55% asphalt content exhibited the opposite trends. The elongation and (Tanδ)max of ER and EAs reduced, whereas the storage modulus and hardness at mid to high temperatures rose. At the microstructural level, the degradation of the resin phase was confirmed by changes in ether, ester, and amide groups, whereas the generation of sulfoxide groups was associated with the oxidation of the asphalt phase. Compared with ER, the surface of EA has obvious defects after aging, which is the main reason for the decrease in contact angle. As the asphalt content increases, EAs exhibit higher carbonyl concentration, more profound oxidation, and more obvious performance degradation. This trend suggests that the resin phase mitigates the aging of the asphalt phase by absorbing harmful UV radiation and oxygen. [ABSTRACT FROM AUTHOR]

A low viscosity tetra‐functional cyclosiloxane epoxy resins (TGTS) is synthesized via a one‐step hydrosilylation reaction and cured separately with four different aromatic diamines to explore the reaction kinetics, network development, and thermal resistance. The hardeners used are 1,3‐phenylenediamine (PDA), diethyl toluene diamine (DETDA), 4,4‐diaminodiphenylmethane (DDM), and 1,3‐bis(4‐aminophenoxy) benzene, because of their availability and aromaticity. During cure with TGTS they all display autocatalytic behavior, but when compared to a traditional organic epoxy resin, diglycidyl ether of bisphenol A (DGEBA) cured with DDM however, the rate constants are about 3 times slower and less exothermic. The DETDA hardener in particular exhibits significantly slower rates of cure when compared to the other amines, being about an order of magnitude slower compared to the PDA curative. This is attributed to higher steric hindrance, compounded by reduced miscibility. The TGTS‐DDM carbon fiber composite displays the most thermal resistance after extended exposure to 220°C, producing the least mass loss and after combustion of about 12% compared to 20% for the DGEBA cured with DDM. The results presented here, illustrate that a tetrafunctional cyclic siloxane epoxy resin, can exhibit excellent processability, evidenced by very low viscosities and long gelation times, whilst also displaying excellent thermal resistance, whether at elevated temperature, or during combustion. [ABSTRACT FROM AUTHOR]

The phenolic‐type phthalonitrile (PN) was added to EP/DDM system in order to enhance the thermal and mechanical performance at high temperature. The influence of the added PN on the curing process of EP/DDM was studied via DSC and the activating energy (Eα) was calculated based on iso‐conversional method. The Eα values corresponding to EP/DDM crosslink reaction remained at about 60 kJ mol−1 while it dramatically increased to 68.2 kJ mol−1 when PN content reached 50 wt% (EP‐PN50). The Tg and char yield at 700°C in N2 increased from141°C, 25.7%, for the neat EP/DDM to 226°C, 68.7% for the EP‐PN50. The measured char yields of the cured blend were higher than the calculated values which implies the interaction between EP/DDM and polyphthalonitrile network. The tensile and bending tests were carried out at 413 K and the modulus of EP‐PN50 remains 2.3 Gpa. On the meantime, the cyano‐functionalized SiO2 (CNSiO2) was prepared to further promote the mechanical behaviors of this resin blend in high temperature. The contact angles of raw SiO2, KH560SiO2, CNSiO2 with EP‐PN50 are 59.3, 52.6, 49.7°, respectively, which confirms the better wettability of CNSiO2 to the EP/PN blend. Furthermore, the tensile and bending tests conducted at 413 K confirmed that the CNSiO2 was more efficient on enhancing the mechanical performance of this EP/DDM/PN system at high temperature. [ABSTRACT FROM AUTHOR]

Bismaleimide (BMI) resins is widely used in the aerospace field because of its excellent properties, but its poor toughness limits the possibility of its application in a wider range of fields. Therefore, a novel bio‐compound, 4‐(allyloxy)‐3‐methoxy‐N‐(3‐(triethoxysilyl)propyl)benzamide (AMTPM), was designed and synthesized from renewable vanillin, which has Schiff‐base structure, silico‐oxygen bond structure, and allyl structure. The chemical structure of AMTPM has been characterized and validated by Fourier transform infrared (FTIR) and hydrogen nuclear magnetic resonance (1H NMR). It was found that the addition of AMTPM can effectively promote the curing behavior of BD resins (BMI and diallyl bisphenol A (DBA) was mixed and cured at the ratio of 1:0.87, named BD resins). AMTPM can affect the thermal stability and improve the mechanical properties of BD‐AMTPM resins (BD resins modified by AMTPM in different addition), and the detailed discussion was conducted. With the increase of AMTPM content, the thermal stability of BD‐AMTPM resins was deteriorated while the residual weight percentage at 800°C (Yc) was increased. When the content of AMTPM reached 12 wt%, the results showed that Yc achieved the values at a magnitude of 37.57%. Meanwhile, the glass transition temperature (Tg) achieved 320°C. Among the BD‐AMTPM resins system, the BD‐6 wt% AMTPM has the best toughness and mechanical properties. The impact strength was increased by 29.2%, the tensile strength was increased by 22.1% and the elongation at break was increased by 44%. The fracture morphology of BD‐AMTPM resins was also studied by scanning electron microscopy (SEM) to support the mechanical experimental conclusions. This study provides a more environmentally friendly and convenient modifier, which is of great significance for expanding the application of bismaleimide resin. Highlights: A bio‐based modifying agent (AMTPM) was designed and successfully synthesized.AMTPM has both Si‐O and Schiff‐base structures.AMTPM can effectively improve the toughness of BD‐AMTPM resins through impact and tensile tests. [ABSTRACT FROM AUTHOR]

Phthalonitrile thermosets are known for their excellent mechanical, physico-chemical, and fire-retardant properties, making them attractive for aerospace and mechanical engineering applications. When producing and applying phthalonitrile-based structural parts, it is essential to consider aspects such as processability and the long-term stability of the material's properties at high temperatures. In our previous studies, we demonstrated that resins containing phosphate-bridged bisphthalonitrile monomers are easily processable due to their low melting temperature and wide processing window. In this study, we investigated the impact of bis(3-(3,4-dicyanophenoxy)phenyl)phenyl phosphate (PPhPN) monomer content on physico-chemical and mechanical properties, thermal stability, and thermal oxidative stability. This research highlights the importance of conducting long-term thermal oxidative aging studies in addition to thermogravimetric analysis to properly assess the stability of thermosets. The findings indicate that adding less than 15% of PPhPN results in the formation of a crystalline phase, which impairs the resin's processability. Conversely, a high PPhPN content reduces the material's thermal oxidative stability. Therefore, based on mechanical and physico-chemical tests after thermal oxidative aging, it can be concluded that a 10–15% concentration of the phosphate-containing monomer enables easy processability of the phthalonitrile resin and provides excellent long-term thermal oxidative stability at temperatures up to 300 °C, while maintaining a flexural strength exceeding 120 MPa and an elasticity modulus of 4.3 GPa. [ABSTRACT FROM AUTHOR]

In this work, 3‐(pyrimidin‐2‐ylthio)phthalonitrile (n‐MP1), non‐peripherally 3‐(pyrimidin‐2‐ylthio) groups substituted Zn (II) phthalocyanine (n‐MP2), and its water soluble derivative (n‐MP3) have been firstly synthesized and characterized with spectral data. The interaction of the n‐MP3 complex with DNA was examined in vitro using UV–visible titrimetric and thermal denaturation assays and in silico by performing molecular docking studies. In addition, the antidiabetic activity of n‐MP3 was revealed spectroscopically by studying α‐glucosidase inhibition activities. The spectroscopic results indicated that n‐MP3 effectively binds to CT‐DNA with a Kb value of 2.0 × 105 M−1 and interacts with CT‐DNA via noncovalent binding mode. Besides, docking studies divulged that n‐MP3 exhibits a stronger binding tendency (BE: −10.64 kcal/mol) with DNA than the control compounds, (7.78 kcal/mol for ethidium bromide and −6.21 kcal/mol for cisplatin). Consequently, due to its strong DNA binding activity, n‐MP3 may be suitable for antimicrobial and anticancer applications after further toxicological test systems. Also, n‐MP3 complex inhibited the activity of α‐glucosidase with the IC50 value of 1.44 ± 0.08 μM, whereas IC50 value of acarbose was 237.24 ± 1.80 μM. Therefore, it can be said that n‐MP3 is a very effective α‐glucosidase inhibitor. [ABSTRACT FROM AUTHOR]

Bisphenol A-based phthalonitrile resin was synthesized by nucleophilic substitution reaction from bisphenol A and 4-nitrophthalonitrile, and then the obtained resin was cured with sulfaguanidine as a novel curing agent. The curing characteristics, kinetics, thermal stability and dynamic mechanical property were studied by standard thermal analysis techniques including DSC, TGA, and DMA. The peak temperature of exothermic peak (T p) and apparent activation energy (E a) of sulfaguanidine cured phthalonitrile resin were 263.20°C and 76.6 kJ·mol−1 respectively, much lower than those of traditional aromatic diamine cured resin. Moreover, the resin cured by sulfaguanidine showed excellent thermomechanical properties and thermal stability. The glass transition temperature (T g) was 284.8°C, the initial thermal decomposition temperature (T d,5%) was 439.6°C, and the char yield at 800°C was 62.1% in nitrogen atmosphere. To sum up, organic guanidine cured phthalonitrile resin exhibits excellent curing characteristics (low T p and E a) and high thermal properties, which provides a promising approach to preparing phthalonitrile resin with high comprehensive performance. [ABSTRACT FROM AUTHOR]

A multifunctional photoinitiator is presented, offering precise control over light‐induced polymerization initiation at 450 nm and material degradation at 365 nm. This is accomplished by covalently linking photoactive bis(acyl)phosphane oxide and photocleavable o‐nitrobenzyl ether moieties onto the surface of γ‐cyclodextrin. Upon degradation, the resulting linear polymers can be easily re‐dissolved in their corresponding monomer and re‐cured, exhibiting superior mechanical properties compared to the pristine material. Moreover, this photoinitiator enables the successful 3D printing of intricate and precise structures, representing a promising general strategy for developing recyclable photoresins for 3D printing applications. [ABSTRACT FROM AUTHOR]

To accomplish the potential of the New‐Space emerging era and facilitate scientific and commercial space exploration, the development of versatile, customized, and affordable space technologies is essential. 3D printing is established as a disruptive technology, enabling the production of complex and lightweight structures with enhanced performance. However, the harsh conditions of the space environment, including atomic oxygen (AO), extreme temperatures, and ionizing radiation, pose significant challenges to the durability and longevity of additive manufacturing‐produced polymers. Until now, there are no additive‐manufacturing polymeric materials that are specifically developed and qualified to withstand space hazards. To address these challenges, novel materials for additive manufacturing, composed of cyanate ester and extended‐bismaleimide are engineered to withstand the extreme conditions in space. The developed materials demonstrate superior thermo‐mechanical properties (flexural stress of 72 MPa and Tg = 260 °C), enhanced durability to AO erosion, ionizing radiation (10 years in orbit), and thermal stability (Td5% = 360 °C). Moreover, it is found that printing orientation governs the AO erosion, thus guiding optimal printing designs for enhanced durability to AO. The materials show improved performance, endurance, and reliability, thus contributing to the development of space‐qualified components and enabling the advancement of additive manufacturing for future space missions. [ABSTRACT FROM AUTHOR]

We introduce the first mechanochemical cyclotrimerization of nitriles, a facile strategy for synthesizing triazine‐containing molecules and materials, overcoming challenges related to carbonization and solubility. Conducting this solid‐state approach in a mixer ball mill with 4‐Methylbenzonitrile, we synthesize Tris(4‐methylphenyl)‐1,3,5‐triazine quantitatively in as little as 90 minutes. Just as fast, this mechanochemical method facilitates the synthesis of the covalent triazine framework CTF‐1 using 1,4 Dicyanobenzene. Material characterization confirms its porous (650 m2 g−1) and crystalline nature. Adjusting the induced mechanical energy allows control over the obtained stacking conformation of the resulting CTFs ‐ from a staggered AB arrangement to an eclipsed AA stacking conformation. Finally, a substrate scope demonstrates the versatility of this approach, successfully yielding various CTFs. [ABSTRACT FROM AUTHOR]

Silicone resins are widely used in various fields because of their excellent high thermal stability. To improve their comprehensive performances, many organic resins have been used for modification of silicone resins. In this article, silicone resins containing phthalonitrile groups were synthesized by the reaction of the silicone resin containing amino groups and 4-(2-oxiranylmethoxy)-1,2-benzenedicarbonitrile. The structures of phthalonitrile-modified silicone resins were characterized by Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance (1H-NMR). The curing process was characterized by differential scanning calorimetry and FT-IR. Thermogravimetric analysis results showed that the cured modified silicone resins had good thermal stabilities. Dynamic mechanical analysis indicated that they owned high glass transition temperature, suggesting that silicone resins containing phthalonitrile groups have high-temperature resistance. [ABSTRACT FROM AUTHOR]

Epoxy-cyanate ester blends have attracted significant attention due to their unique synergistic properties and versatility in high-performance applications. However, achieving precise control over the phase-separated structures in these blends remains a challenge. In this work, we present a strategy for the preparation of epoxy-cyanate ester blends with high-performance through staged curing-induced phase separation. By incorporating a thermally latent catalyst, 4-ethyl-2-methylimidazole tetraphenylborate, into the epoxyanhydride-cyanate system, the reactivity differences of multiple curing reactions within the blend were precisely controlled, thereby inducing the formation of well-defined nanophase-separated structures. The polymer systems prepared exhibit high mechanical properties and heat resistance, primarily due to the interpenetrating networks created by the epoxy-anhydride-cyanate ester and the formation of nanodomains induced by the staged curing process. Furthermore, epoxy-cyanate ester blends demonstrate outstanding hygrothermal resistance due to the low polarity of the crosslinked network structure. This work provides new insights into regulating the microstructure of the thermosetting blends and expands the potential applications of these materials in fields requiring long-term durability and reliability. [ABSTRACT FROM AUTHOR]

As a high‐performance engineering plastic, the acrylonitrile‐butadiene‐styrene (ABS) resin possesses excellent heat resistance, chemical resistance, and toughness. However, there is a lack of flow properties of the ABS resin for many processing operations. With the aim of enhancing the flowability of the ABS resin, the effect of N,N′‐ethylene bis oleamide (EBO) as a new lubricant on the melt flow rate (MFR), torque value, and rheological behavior of the ABS resin was investigated. The result showed the MFR of the ABS resin with 2.0 wt% EBO was 22.1 g/10 min, which was improved by 49% compared with the pure ABS resin (14.8 g/10 min). The torque value of the ABS resin, including 2.0 wt% EBO (1.69 N m) was lower than that of the pure ABS resin (2.03 N m). The rheological study further indicated that EBO can reduce the complex viscosity of the ABS resin. The above results indicated that EBO was an effective lubricant for the ABS resin. A possible lubrication mechanism was proposed based on the consequences of the rotational rheometry, dynamic mechanical analysis, and molecular dynamics simulation. EBO decreased the entanglement density of the polystyrene‐acrylonitrile (SAN) molecular chains and increased the mobility of the SAN molecular chain segments. On the other hand, EBO increased the free space of motion of the SAN molecular chain segments due to the free‐volume effect thereby increasing the mean square displacement of the system. This work will provide a new way to achieve the high‐flow ABS resin and provide new insights into the lubrication mechanism of lubricants in the ABS resin thereby expanding the applications of the ABS resin. [ABSTRACT FROM AUTHOR]

In this study, we succesfully synthesized bio‐benzoxazine resins using eugenol, a bio‐based phenolic compound, in combination with three distinct functional amines: ethanamine, aniline, and hexane‐1,6‐diamine. Characterization of the resulting bio‐benzoxazine resins, namely E‐ea (eugenol, ethanamine), E‐a (eugenol, aniline), and E‐dh (eugenol, hexane‐1,6‐diamine), was performed through 1H NMR spectroscopy, FTIR spectroscopy, high‐resolution mass spectrometry, and elemental analysis. Thermal properties were investigated using thermogravimetric analysis (TGA) for both the eugenol‐derived bio‐benzoxazines (E‐ea, E‐a, E‐dh) and their corresponding polybenzoxazines (PE‐ea, PE‐a, PE‐dh). Notably, all eugenol‐based polybenzoxazines exhibited excellent thermal stability with very similar characteristics. Our findings suggest that the presence of allyl groups in eugenol promoted a more cross‐linked network structure compared to other functional groups on amines. As a result, eugenol‐derived bio‐benzoxazines demonstrated superior thermal properties, illustrated by their impressive char yields: PE‐ea; 45.6%, PE‐a; 45.1%, and PE‐dh; 44.1%. [ABSTRACT FROM AUTHOR]

The copolymer precursor, poly [4-(4-vinylbenzyl)oxy)phthalonitrile]-co-methyl methacrylate (poly (VBOPN-co-MMA)), was synthesized through copolymerization of VBOPN and MMA at a temperature of 110°C. Subsequently, a single-chain polymer complex of cobalt phthalocyanine (SCP-CoPc) was formed at 150°C by intramolecular macrocyclization between the cobalt and the phthalonitrile group in poly (VBOPN-co-MMA), using excess cyclohexanol. The formation of the SCP-CoPc complex was confirmed through various spectroscopic techniques such as UV/Vis, FT-IR, 1H-NMR, and 13C-NMR. In particular, the disappearance of -CN band at 2232 cm−1 from FT-IR indicated the formation of the SCP-CoPc complex, while the presence of specific absorption bands in the UV/Vis spectrum further confirmed its creation. The electrical, dielectric, optical, and thermal properties of the SCP-CoPc complex and SCP-CoPc/ZnO 5% composites were investigated. The SCP-CoPc/ZnO 5 wt% nanocomposite exhibited improved dielectric and DC conductivity with increasing temperature. The activation energy (Ea) was found to be 0.35 eV for SCP-CoPc and 0.25 eV for SCP-CoPc/ZnO 5 wt% nanocomposite, indicating that the electrical conductivity followed the Arrhenius equation. The optical properties, including band gap, dielectric constant, and refractive index, were calculated for the SCP-CoPc/ZnO 5 wt% nanocomposite. The SCP-CoPc complex possessed a band gap of 2.89 eV, while the SCP-CoPc/ZnO 5 wt% nanocomposite had a slightly reduced band gap of 2.36 eV. The refractive indices of SCP-CoPc and SCP-CoPc/ZnO 5 wt% were also determined. [ABSTRACT FROM AUTHOR]

Psoriasis, a chronic immune-mediated skin disorder affecting over 125 million people globally, is characterized by abnormal keratinocyte proliferation and immune cell infiltration. Photodynamic therapy (PDT) remains underutilized in the treatment of psoriasis despite its potential as a promising and effective therapeutic approach. This study aimed to explore the efficacy of zinc phthalocyanine (ZnPc) and its sugar conjugates as potential antipsoriatic agents. We successfully synthesized protected and unprotected sugar-conjugated zinc phthalocyanines and evaluated their potential against cytokine-stimulated HaCaT keratinocytes, as well as an established IMQ psoriasis-like in vivo model. Tetrasubstituted protected glucose–ZnPc (Glu-4-ZnPc-P) demonstrated superior phototoxicity (IC50 = 2.55 µM) compared to unprotected glucose conjugate (IC50 = 22.7 µM), protected galactose–ZnPc (IC50 = 7.13 µM), and free ZnPc in cytokine-stimulated HaCaT cells (IC50 = 5.84 µM). Cellular uptake analysis revealed that IL-17A, a cytokine that plays a central role in the pathogenesis of psoriasis, enhanced unprotected Glu-4-ZnPc uptake by 56.3%, while GLUT1 inhibitor BAY-876 reduced its accumulation by 23.8%. Intracellular ROS generation following Glu-4-ZnPc-P-PDT was significantly increased after stimulation with IL-17A, correlating with in vitro photocytotoxicity. In vivo PDT using Glu-4-ZnPc-P exhibited significant improvement in Psoriasis Area and Severity Index (PASI), inhibiting splenomegaly and restoring normal skin morphology. This study highlights sugar-conjugated zinc phthalocyanines as potential candidates for targeted PDT in psoriasis, providing a basis for further clinical investigations. [ABSTRACT FROM AUTHOR]

The aim of the work is to develop two functionalized castor oil-based polyglycidyl ethers containing benzene rings by ring-opening etherification and alkylation reaction, respectively: phenoxy castor oil-based polyglycidyl ether (POCOGE) and phenolic castor oil-based polyglycidyl ether (PCOGE). Castor oil-based polyglycidyl ethers were introduced into E-51, which is a common type of bisphenol A epoxy resin. The thermomechanical performances of the polymer blends were evaluated. The addition of the synthetic castor oil-based polyglycidyl ethers showed an enhancement of E-51 in both toughness and flexibility without sacrificing bending strength. The tensile strength reached 81.0 MPa and 86.4 MPa, which were 26.5% and 34.9% higher compared to that of pure E-51. Meanwhile, the impact strength reached 28.1 kJ m−2 and 19.4 kJ m−2, an increase of 147% and 70.3%, respectively, compared with E-51. Scanning Electron Microscope (SEM) graphics exhibited those cured polymers had ductile fracture. The non-isothermal curing kinetics of different curing systems were analyzed by Málek's method and conformed to the Šesták–Berggren SB(m,n) model. This study aims to address the inadequate stiffness of bio-based epoxy resins and extend the scope of bio-based epoxy resins with versatile functionality. [ABSTRACT FROM AUTHOR]

This study reports the fabrication of quartz fabric reinforced phthalonitrile composite possessing good thermal and wave-transmitting properties. Phthalonitrile-terminated oligomer PN-SF curing behavior was investigated using differential scanning calorimetry (DSC) and dynamic rheological analysis (DRA), revealing a good processability pre-curing temperature of only 175°C. The thermoset exhibited the 5% loss temperature about 462°C, and after the temperature rising to 400°C and 400°C/2 h aging, the weight loss was only 10%, indicating that the resulting thermoset possessed outstanding thermal property. Moreover, the resulting thermosets possessed extremely high glass transition temperature (Tg) about 420°C. Besides, the quartz fabric/phthalonitrile composite possessed extremely excellent mechaical properties. Importantly, the transmission efficiencies can reach 87% at a certain frequency at the incident angle of 0°∼35°, indicating its well waving-transmitting performance. Meanwhile, the composite exhibited stable and relatively low dielectric constant and dielectric loss at the range of 12∼18 GHz. This study can serve as a basis for rapid evaluation of the high heat resistance and waving-transmitting phthalonitrile resin-based composite in various application environments. [ABSTRACT FROM AUTHOR]

A novel quinoxaline-based phthalonitrile monomer, namely, 4,4′-(((quinoxaline-2,3-diylbis (oxy))bis (3,1-phenylene))bis (oxy))di-phthalonitrile (QDOP), was successfully synthesized by nucleophilic substitution reaction, which exhibits a low melting point (85°C) and a wide processing window (150°C). The QDOP monomer was cured with 4-aminophenoxy phthalonitrile (APPH) as catalyst by different temperature programs, and the curing process and kinetics were discussed in detail by non-isothermal differential scanning calorimetric (DSC). The QDOP polymer mainly forms triazine, isoindoline and phthalocyanine structure, as revealed by Fourier transform infrared (FTIR) spectroscopy, and its properties improved with the increase of post-curing temperature and curing time. After post-curing at 380°C, the polymer exhibited high storage modulus (3731 MPa), high glass-transition temperature (>400°C), and outstanding thermal stability and thermal oxidation stability. [ABSTRACT FROM AUTHOR]

[Display omitted] The development of stable and efficient heterojunction photocatalysts for wastewater environmental purification exhibits a significant challenge. Herien, a promising binary heterojunction complex comprising boron subphthalocyanine bromide/bismuth oxychloride (SubPc-Br/BiOCl) was successfully synthesized using the hydrothermal method, which involved the self-assembled of SubPc-Br on the surface of BiOCl via intermolecular π-π stacking interactions to compose an electron-transporting layer. The photocatalytic efficiency of SubPc-Br/BiOCl for the degradation of tetracycline and the minocycline exhibited a substantial improvement of 29.14% and 53.72%, respectively, compared to the original BiOCl. Experimental characterization and theoretical calculations elucidated that the enhanced photocatalytic performance of the SubPc-Br/BiOCl composite photocatalysts stemmed from the S-scheme electron transport mechanism at the interface between BiOCl and SubPc-Br supramolecules, which broadened the visible light absorption range, increased the carrier molecular efficiency, and accelerated the carriers. Furthermore, molecular dynamic (MD) simulations provided insights into the action trajectories of the two semiconductors, revealing that the presence of SubPc-Br enhances the water and organic pollutant adsorption capabilities of the BiOCl surface within the supramolecular array system. In conclusion, the synthesis and analysis of the binary heterojunction complex SubPc-Br/BiOCl yield valuable insights into the efficient photocatalytic degradation of antibiotics, holding great promise for diverse environmental applications. [ABSTRACT FROM AUTHOR]

This study evaluates the effectiveness of a silica preceramic polymer for joining and coating Plasma Electrolytic Oxidated (PEO) aluminum components at temperatures below 200 °C. PEO aluminum slabs were coated and joined with a silica precursor polymer (Durazane1800, Merck, Darmstadt, Germany), both with and without the addition of 48 wt% silica nanoparticles, and cured at 180 °C for 4 h in air. Thermogravimetric analysis assessed the curing process and thermal stability, while X-ray diffraction confirmed the polymer's conversion to amorphous silica after heating at 1200 °C. Resistance to humid environments was tested by soaking coated samples in tap water for a week, with no mass variation observed. Mechanical testing through tensile mode and tensile lap tests showed that adding 48 wt% silica nanoparticles significantly improved joint cohesion and nearly quadrupled mechanical strength. Fracture surfaces were examined using Field Emission Scanning Electron Microscopy, and composition analysis was performed with Energy Dispersion X-ray Spectroscopy. Crack detection was conducted using Computer Tomography with an in situ bending test setup to obtain the mechanical resistance of the PEO coating. The results indicate that the silica preceramic polymer is suitable for joining and coating PEO aluminum components, with silica nanoparticles enhancing mechanical strength and providing excellent thermal stability and resistance to humidity. [ABSTRACT FROM AUTHOR]

In this work, a series of aldehyde‐substituted phthalocyanine compounds (1, 3, and 5) were prepared by the cyclotetramerization of the 4‐(5‐(diethylamino)‐2‐formylphenoxy) phthalonitrile (a) and the corresponding metal salts. Schiff base‐substituted phthalocyanines (2, 4, and 6) were derived from an aldehyde‐substituted phthalocyanine (1, 3, and 5) via the reaction of aldehyde‐substituted phthalocyanines with an amine reagent. The compounds that were obtained were characterized using FT‐IR, 1H {13C} NMR, UV–Vis, and MS spectra (a and 1–6). The inhibitory qualities of synthesized aldehyde and Schiff base‐substituted complexes against the enzymes butyrylcholinesterase (BChE) and acetylcholinesterase (AChE) were assessed. The majority of phthalocyanines exhibited strong enzyme‐inhibiting properties. Out of the six produced phthalocyanines, 3 and 4 displayed the most intriguing profiles as submicromolar selective AChE inhibitors (IC50 = 0.060 μM), whereas 1 demonstrated the most potent BChE inhibitor (IC50 = 0.024 μM). The aggregation studies of CoPcs, CuPcs, and ZnPcs (1–6) were also carried out in this work. [ABSTRACT FROM AUTHOR]

In this study, magnesium (II) phthalocyanines (2a, 3a) and their water‐soluble derivatives (2b, 3b) were synthesized via multistep reactions. The structures of these phthalocyanines were identified by FT‐IR, NMR, MALDI‐TOF, and UV–Vis spectroscopy. The ct‐DNA binding (UV–Vis absorption, competitive EB binding, and agarose electrophoresis studies) and supercoiled plasmid DNA nuclease properties (hydrolytic, photonuclease, oxidative nuclease, and photooxidative nuclease) of the water‐soluble compounds were investigated using different methods. The DNA binding constant (Kb) values of 2b and 3b were calculated as 8.45 ± (0.25) × 104 and 7.71 ± (0.13) × 104 M−1 at 25°C, respectively. The results showed that 2b had a stronger ct‐DNA binding effect than 3b according to Kb and r values. The DNA nuclease studies claimed that both compounds indicated photonuclease activity on plasmid DNA depending on the light dose. Additionally, 2b had a higher photonuclease capacity than 3b. All of these results showed that 2b had promising potential as a photosensitizer agent for photodynamic therapy. [ABSTRACT FROM AUTHOR]

Thermally cured products (BLmP, m = 3, 33, and 12) of 4,4′-bismaleimidodiphenylmethane (BMIDPM), a thiol-terminated disulfide-containing polyether (LP-m), and pentaerythritol tetrakis(3-mercaptopropionate) (PETMP) were prepared at a maleimide:thiol ratio of 1:1. The influence of the feed monomer ratio, molecular weight, and crosslinking agent content of LP-m on the thermal, mechanical, and self-healing properties was investigated. Fourier-transform infrared (FT-IR) spectroscopy of the cured products revealed that the thiol-maleimide "click" reaction proceeded almost completely. The glass transition temperature (Tg), tensile strength, and tensile modulus of the cured products decreased with an increase in the fraction and molecular weight of LP-m and a decrease in the crosslinking agent content of LP-m. All the cured products were healed by treatment at 125 °C/5 MPa for 3 h. The tensile strength healing efficiency increased with an increase in the fraction and molecular weight of LP-m and a decrease in the crosslinking agent content of LP-m. [ABSTRACT FROM AUTHOR]

In this study, we evaluated the effects of three resins with different refractive index on the viscosity and curing behavior of aluminum nitride (AlN) ceramic suspensions. Our findings indicate that the viscosity of the AlN suspensions increased with the concentration of polyethylene glycol o -phenylphenyl ether acrylate (OPPEA). Conversely, the viscosity decreased with increasing concentrations of cyclic trimethylolpropane formal acrylate (CTFA) and ethylene glycol phenyl ether acrylate (PHEA). Regarding the curing behavior, the AlN ceramic suspension prepared with OPPEA exhibited the largest cure depth and excess width, whereas the suspension prepared with CTFA had the lowest cure depth and excess width. Further analysis of the sensitivity and critical energy revealed that the suspension containing OPPEA demonstrated the highest sensitivity in the vertical direction and the lowest sensitivity in the horizontal direction. This implies that the smallest critical energy is in the vertical direction, and the largest critical energy is in the horizontal direction. Additionally, an increase in the content of the plasticizer dibutyl phthalate (DBP) was beneficial for reducing cracks in the AlN ceramic debinding bodies. Finally, high-performance AlN ceramics were produced, exhibiting a relative density exceeding 98 %, a bending strength of 470.39 ± 6.5 MPa, and a thermal conductivity of 163.45 W/m·K. [ABSTRACT FROM AUTHOR]

In this study, chitosan (CS)‐based macromolecular synergistic antioxidant CS‐UC‐TDAA containing carbon–carbon double bond, hindered phenol, and aromatic secondary amine was prepared by using CS,10‐undecenoyl chloride (UC), p‐aminobenzoic acid (AA), 3,5‐di‐tert‐butyl‐2‐hydroxybenzaldehyde (TD) via esterification, Schiff base reaction, and acylation reaction. The molecular structure of CS‐UC‐TDAA was characterized by fourier transform infrared, 1H NMR, and elemental analysis. The effects of macromolecular synergistic antioxidant CS‐UC‐TDAA, small molecular antioxidant TDAA, commercial antioxidant 4020, and butylated hydroxytoluene (BHT) on the antiaging properties of styrene‐butadiene rubber (SBR)/SiO2 composites were systematically studied by accelerated thermo‐oxidative aging test, thermogravimetric (TG) analysis, and methanol Soxhlet extraction experiment. The experimental results show that CS‐UC‐TDAA has more outstanding thermo‐oxidative aging resistance, thermal stability, and solvent extraction resistance in SBR/SiO2 composites than TDAA, 4020, and BHT. The macromolecular synergistic antioxidant CS‐UC‐TDAA endows SBR/SiO2 composites with more durable antiaging performance, which is attributed to the synergistic antioxidant effect of its hindered phenol and aromatic secondary amine groups. Additionally, its resistance to migration and extraction is facilitated by the crosslinking of the carbon–carbon double bond with the rubber and its substantial molecular weight. [ABSTRACT FROM AUTHOR]

A phthalonitrile‐based bent shaped push‐pull dibenzodioxin was synthesized using an efficient and rapid monowave reactor‐assisted protocol in acceptable yields. When aqueous Fe3+ ion solution was added to the bent dibenzodioxin in dimethyl sulfoxide (DMSO), the fluorescence intensity of bent dibenzodioxin at 450 nm was quenched significantly. UV‐visible and fluorimetric measurements displayed high selectivity and sensitivity towards Fe3+ over other metal ions, with a low detection limit of 0.67 μM. Fluorimetric investigations like interference and reversibility test of bent‐dibenzodioxin with Fe3+ led to proving it as a potential canditate for chemosensor application. Job's plot showed 1 : 2 stoichiometry between the bent‐dibenzodioxin and Fe3+ ions respectively and it was proposed that the the binding of one of the Fe3+ ion is from the phenanthroline‐like bent pocket, featuring two oxygen atoms and the other Fe3+ ions binds with the two ortho‐dinitrile units of the bent‐dibenzodioxin. [ABSTRACT FROM AUTHOR]

A series of versatile phthalocyanine precursors, consisting of gem-dibromovinyl phthalonitrile derivatives, were synthesized and characterized by various spectroscopic techniques. The assigned structures were further supported by X-ray crystallographic techniques. The crystal structures showed primarily C-H...N, C-H...Br, C-Br...N and π...π interactions. The overall intermolecular interactions in the structures were quantified and fully described by Hirshfeld surface analysis. In addition, energy-frame calculations were used to analyse the three-dimensional topology of the crystal packing. The dispersion energy framework of all compounds was shown to be dominant over the electrostatic framework. [ABSTRACT FROM AUTHOR]

The interfacial bonding is of essential importance for the mechanical properties of high-temperature resistant carbon fiber/phthalonitrile composite materials. To promote the interfacial adhesion of carbon fiber/phthalonitrile composites, three surface modification methods, namely HP302 sizing, diazotization modification, and oxidation-diazotization modification, were applied and compared. The results showed that the de-sizing treatment barely affected the mechanical properties of the composites. Both re-sizing with HP302 agent and diazotization modification improved the mechanical properties, while the mechanical properties were drastically decreased via the oxidation-diazotization modification. Among these surface modification methods, the diazotization treatment derived the best mechanical properties of carbon fiber/phthalonitrile composites both at room and high temperature. Specifically, the flexural strengths were 345 MPa (RT), 525 MPa (300°C), and 442 MPa (400°C), which were 47%, 302%, and 281% higher than those of the pristine composites. The interlaminar shear strengths were 33 MPa (RT), 26 MPa (300°C), and 27 MPa (400°C), which were all over twofold than those of the original counterparts. [ABSTRACT FROM AUTHOR]

A new series of high-temperature resistant bisphthalonitrile resins containing trifluoromethyl groups were prepared based on 4,4'-(hexafluoroisopropylidene) bisphthalonitrile (BFPh), which was toughened by hexafluoroisopropylidene-containing poly (aryl ether nitrile) oligomer capped by phthalonitrile (FPEN-Ph) in the different content. In addition, glass fiber reinforced composites were prepared by hot pressing process. The structure of the oligomer was characterized by FTIR and 1HNMR. The curing behavior of the blends was studied by DSC. Thermal stability and mechanical properties were also studied. The results showed that the introduction of appropriate content of FPEN-Ph could improve the reactivity of the curing reaction. TGA and DMA results showed that the cured polymers and composites had excellent thermal properties. The residual mass of FPEN-Ph content of 10% at 800°C was 72.4%, and the 5% thermal degradation temperature (T5%) under inert atmosphere was 530°C. The flexural strength of glass fiber reinforced composites was about 592.7 MPa, and the shear strength was about 61.6 MPa, showing excellent mechanical properties. The high-tech thermosetting resin was toughened and enhanced at the same time without reducing heat resistance. [ABSTRACT FROM AUTHOR]

A fast‐curing epoxy with improved mechanical properties, self‐healing and re‐processability was designed using a tailored Schiff based motif that offered dual covalent adaptable network (CAN) in epoxy. The designer motif is a dynamic hardener with both acetal linkage and a Schiff base motif in the same molecule which allowed us to gain a mechanistic insight into the evolving transient network in epoxy vitrimers. The dynamic hardener besides offering a cross‐linked network in epoxy can facilitate rapid exchange reactions, resulting in a material with high tensile strength (74 MPa), high glass transition temperature (121°C), and that can be re‐purposed through solvent induced degradation. The proposed dynamic curing agent is suitable to be employed as a coating material on substrates to ensure excellent self‐healing and re‐processability ensuring chemical recyclability. Few carbon fiber‐based laminates were prepared using the epoxy vitrimer and the recovery of CF post laminate preparation clearly demonstrates the closed‐loop circularity in epoxy vitrimers. Highlights: A unique dynamic curing agent is designed consisting of an aldehyde (salicylaldehyde) and an amine and acetal containing species (amino acetaldehyde dimethyl acetal).It facilitates imine and acetal exchange that can bond at temperatures <60°C and break at temperatures >105°C as evidenced by the vitrimer transition temperature.Epoxies show high tensile strength (74 MPa), exceptional Tg (121°C), fast stress relaxation and an activation energy of 96.2 KJ/mol.The imine‐acetal exchange system rendered the epoxies re‐processable, malleable and re‐usable. [ABSTRACT FROM AUTHOR]

Background: Organic dyes often have shorter lifetimes in the excited state, which is a major obstacle to the development of effective photoredox methods. The scientific community has shown a great deal of interest in a certain class of organic chromophores because of their unique characteristics and effectiveness. One characteristic of the molecules under research is thermally activated delayed fluorescence (TADF), which is only observed in molecules with a tiny energy gap (often less than 0.2 eV) between their lowest two excited states, i.e., singlet excited state (S1) and triplet excited state (T1). The extended singlet excited states arising from TADF and the simplicity with which their redox potentials may be altered make the isophthalonitrile family of chromophores an attractive option for organic photocatalyst applications. Methods: The Biginelli reaction between β-ketoesters, arylaldehydes, and urea/ thiourea has been used to build a sustainable technique for the production of 3,4- dihydropyrimidin-2-(1H)-one/thione derivatives. In the present study, the development of a green radical synthesis approach for this class of compounds is addressed in depth. As a photocatalyst, a new halogenated dicyanobenzene-based photosensitizer was employed in this study. As a renewable energy source activated by a blue LED, it was dissolved in ethanol, at room temperature in air atmosphere. The primary objective of this research is to employ a novel donor-acceptor (D-A) based on halogenated cyanoarene that is affordable, easily available, and innovative. Findings: The 3DPAFIPN [2,4,6-tris(diphenylamino)-5-fluoroisophthalonitrile] photocatalyst, a thermally activated delayed fluorescence (TADF), induces single-electron transfer (SET) in response to visible light, offering a straightforward, eco-friendly, and highly efficient process. Additionally, we determined the 3,4-dihydropyrimidin-2-(1H)-one/thione derivatives turnover frequency (TOF) and turnover number (TON). It has also been demonstrated that gram-scale cyclization is a workable method for industrial purposes. [ABSTRACT FROM AUTHOR]

A promising high temperature phthalonitrile (PN) resin composed of a polyetherketoneketone (PEKK) core bridged by two bisphenol A linkers and end capped with PN groups is presented. This PEKK‐PN resin was characterized via differential scanning calorimetry, thermogravimetric analysis, proton nuclear magnetic resonance spectroscopy, scanning electron microscopy, dynamic mechanical analysis, attenuated total reflection Fourier transform infrared, and rheometry. The PEKK‐PN resin was evaluated with two different compositions containing 1) 70:30 PEKK‐PN to bisphenol A PN (n = 0) and 2) pure PEKK‐PN. The 70:30 PEKK‐PN resin was mixed with bis[4‐(3‐aminophenoxy)phenyl]sulfone and exhibited a melt viscosity of 271 cP, much lower than the 657 cP viscosity of the pure PEKK‐PN mixture. Void‐free PEKK‐PN polymers were easily prepared by degassing and curing up to 380°C, resulting in fully crosslinked networks exhibiting thermal stability above 500°C and a 75% char yield. Additionally, the cured PEKK‐PN polymer samples displayed good mechanical integrity retaining 50% stiffness at 300°C. This combination of properties suggests these new PEKK‐PN resins are excellent materials for high temperature thermosets in composite applications. [ABSTRACT FROM AUTHOR]

Phthalonitirile-oxazol-5-ones (Pht-Ox), were synthesized with 4-(4-formylphenoxy) phthalonitrile and benzoylglycine derivatives. The original compounds prepared in the reaction pathway were characterized by the combination of FT-IR, 1 H and 13 C NMR, UV–vis and MS spectral data. achieved. To obtain the photophysical data of the synthesized Pht-Ox derivatives were used spectrophotometric and spectrofluorimetric methods. Evaluation of the absorption and emission properties of the structures was carried out in three different solvents. Maximum absorption and emission wavelengths (λ; nm), molar extinction coefficients (ε; cm− 1 M− 1) and Stoke's shifts (ΔλST; nm) of Pht-Ox derivatives were declared. [ABSTRACT FROM AUTHOR]