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2-(Naphthalene-1-yl oxy)-2-oxoethyl methacrylate (NOEMA) was synthesized from reaction of naphthalene-1-yl 2-chloroacetate and sodium methacrylate and its homopolymer was prepared by free-radical polymerization method at 60°C. The glass transition temperature of pure poly(NOEMA) was estimated as 102°C by differential scanning calorimetry technique, whereas that of poly(NOEMA) containing 10 wt% nanographene was 83°C. While pure poly(NOEMA) from thermogravimetric analysis measurements was indicating a decomposition at 290°C, poly(NOEMA) composite containing 10 wt% nanographene showed thermal decomposition temperature at 261°C. Semiconducting composites of poly(NOEMA) have been prepared by adding nanographene particles to poly(NOEMA) for preparing nanocomposites with different weight percentages (2, 3, 4, 5, and 10 wt%). The dielectric constant, ∊ ′, and dielectric loss factor, ∊ ″, of pure poly(NOEMA) were 3.66 and 0.052, respectively, whereas those of poly(NOEMA) containing 10 wt% nanographene were 186 and 210,152, respectively. Alternating current (AC) conductivity of pure poly(NOEMA) was 2.03 × 10−9 S cm−1, whereas that of poly(NOEMA) containing 10 wt% nanographene was 0.00134 S cm−1. AC conductivity mechanism of poly(NOEMA)/10 wt% nanographene composite indicated the correlated barrier hopping model. Activation energy values of poly(NOEMA)/ x wt% nanographene composites was estimated to be between 4.783 eV and 0.209 eV. The polymer composite/p-Si thin-film heterojunction diode properties have been investigated from current–voltage at room temperature. The electrical parameters of the prepared diodes such as ideality factor (n), the barrier height (BH; Φ b), rectification ratio, and reverse saturation current (I o) were investigated at dark and room temperature. The ideality factor (n) value of the Al/poly(NOEMA)/ x wt% nanographene/p-Si/Al diode for dark was found to be between 5.147 and 7.504, respectively. The BH (Φ b) value of the Al/poly(NOEMA)/ x wt% nanographene/p-Si/Al diode at dark was found to be between 0.228 and 0.64. [ABSTRACT FROM AUTHOR]

Abstract: The 4‐(2‐bromoisobutyroyl methyl)styrene [BBMS] monomer was synthesized. The homopolymer of BBMS was prepared by free radical polymerization method. The decomposition behavior of P(BBMS) was thermally investigated by thermogravimetric analysis (TGA). For thermal decomposition kinetics of poly(BBMS), Flynn–Wall–Ozawa method was applied to thermogravimetry curves. The first step, which is one of the two decomposition stages, is comprehensively related to elimination of hydrogen bromide and the other step is related to a multi‐step process. The activation energy (Ea) of thermal decomposition of the first step and 50% weight loss is 148.5 and 190.7 kJ/mol, respectively. The results showed that the side group elimination without chain breaking comprehensively proceeded at lower temperature, and at progressive temperatures subsequently the specific chain scission did so. Degradation of poly(BBMS) did not lead to depolymerization. 1H, 13C‐NMR, and FT‐IR analyses showed that the decomposition products during degradation of poly(BBMS) to 260°C were comprehensively HBr and methacrylic acid. Electrically conducting graphene‐based poly(BBMS) composites were prepared. The DC and AC electrical measurements of graphene‐based poly(BBMS) composites were carried out. The AC dielectric measurements of poly(BBMS) were investigated up to 70°C between 100 Hz and 20 kHz depending on the alternating current conductivities. The dipolar functional groups (C–O, C=O, and Br) of the BBMS segment possesses significantly affect the dielectric constant. Also, the activation energy profile of different graphene/poly(BBMS) composites were revealed by measuring DC conductivity of individual composite material. [ABSTRACT FROM AUTHOR]

The 3-acetamido propyl acrylate [AcAPA] (monomer) was synthesized. The homopolymerization of AcAPA was carried by normal free radical polymerization procedure within tetrahydrofuran at 60 oC using AIBN as the initiator. The poly(AcAPA) composites embedded europium(III)chloride (EuCI3) were prepared. Dependent of temperature and frequency on the dielectric characteristics were investigated in a frequency range starting from 100 Hz to 20000 Hz and in a temperature range from 243 K to 333 K. The results showed that the dielectric loss and dielectric constant increased, and the highest dielectric values were estimated in the case of poly(AcAPA) composites loaded EuCI3 and graphite as well. The FT-IR results indicated that the structural characterization of poly(AcAPA) is strongly affected by the incorporation of EuCI3. Thermal analysis results show that the thermal stability of the EuCI3-doped poly(AcAPA) composites has improved compared to the pure poly(AcAPA). The thermal property of composites has improved significantly due to an increasing in filler loadings showing that a good coordination exists between EuCI3 particles and poly(AcAPA). The dielectric constants of poly(AcAPA)/EuCI3 composites have significantly improved with comparatively low dielectric loss values, indicating that the composites can be considered as a crucial material for embedded capacitor applications. Electrically conducting graphite-based poly(AcAPA)/EuCI3 composites were prepared and the surface morphology of polymer composites were characterized by SEM micrographics. Also, the dc electrical conductivities of graphite-based poly(AcAPA)/EuCI3 were investigated. [ABSTRACT FROM AUTHOR]

The biological activity of both cyclophosphazenes and peptides makes these compounds important for new studies in medicinal chemistry. For this purpose, five different phosphazene-peptide conjugates synthesized from dichlorocyclotriphosphazene and tyrosine-containing tripeptides. The synthesized compounds were evaluated for their in vitro cytotoxic activities against human breast (MCF-7) and colon (Caco-2) cancer cell lines using MTT assay. The derivatives induced cell death through DNA damage, with notable effects in Caco-2 cell lines. Specifically, DTVV, DTVG, and DTVA were cytotoxic at 50 and 100 μM, while DTVP and DTVM were effective at 25, 50, and 100 μM. DTVM outperformed Tamoxifen at 50 μM in the MCF-7 cell line. DNA damage studies of the compounds were performed using the comet assay method, evaluating tail length, tail density, olive tail moment, head length, and head density parameters. The findings indicated that cell death occurred via a DNA damage mechanism. The molecular intricacies of DTVA, DTVG, DTVM, DTVP and DTVV within the VEGFR2 kinase domain (3VHE) and Cyclophilin_CeCYP16-Like Domain (2HQ6) binding pockets and various interactions, docking scores and potential activities of these derivatives were investigated. The differences in docking scores and interaction profiles highlight the potential efficacy and specificity of these compounds in targeting breast and colon cancer cells. These findings highlight the potential of phosphazene-peptide derivatives as therapeutic agents in cancer treatment., (© 2024 Wiley-VCH GmbH.)