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A mode-mismatched thermal lens spectrometry (TLS) technique, in a pump–probe two-laser-beam configuration, was employed for the experimental determination of the thermal properties of four selected well-characterized polyolefin homopolymer films. We investigated the thermal diffusivity (D) and thermal conductivity (κ) of high-density polyethylene, low-density polyethylene, linear low-density polyethylene, and polypropylene. We also measured the structural properties (i.e., average molecular weight, polydispersity index, branching number), along with the rheological and thermal properties (i.e., melting point, specific heat capacity Cp, degree of crystallinity) of samples by high-temperature gel permeation chromatography (HT-GPC), rheometric mechanical spectrometry (RMS), differential scanning calorimetry (DSC), and densitometry. The relationship between microstructural properties such as degree of crystallinity, D, and κ was investigated. The results show that there is good correlation between the degree of crystallinity and D. The TL technique enables measurement of D in semitransparent thin films within an uncertainty of 4%.

Crystal structure, characterization, Hirshfeld surface analysis and DFT studies of two [propane 3-bromo-1-(triphenyl phosphonium)] cations containing bromide (I) and tribromide (II) anions: The anion (II) as a new brominating agent for unsaturated compounds.

A new hybrid phosphonium bromobismuthate compound was synthesized and characterized by 1H NMR, 13C NMR, 31P NMR, FT‐IR, differential scanning calorimetry (DSC) and single‐crystal X‐ray diffraction analysis. The crystal packing structures of title compound were stabilized by various intermolecular interactions especially of the type CH···Br hydrogen bonds between phosphonium cations and [Bi2Br9]3− anion. The relative contribution of various close contacts and 2D fingerprint plots of title compound and three analogous structures obtained from Cambridge Structural Database (CSD) were investigated by Hirshfeld surface analysis. Furthermore, the catalytic activity of title compound was investigated in heterocyclization reaction for the synthesis of significant and pharmacologically useful benzimidazole and benzoxazole derivatives. The results indicated that the yields of the product for aldehydes bearing p‐substituents and o‐substituents were higher than for m‐substituent ones. In addition to selectivity, simplicity of operation, waste minimization, ease of manipulation, short reaction time, excellent yield of product, and easy workup, this technique uses title compound as the catalyst, which is green, recyclable, soft, remarkably nontoxic, and easy to handle.