New aromatic−aliphatic polyethers containing alkyl- or alkoxy-substituted oligophenyl units were synthesized. The polyethers were characterized by viscosimetry, gel permeation chromatography, thermal and mechanical analysis, NMR, and UV−vis luminescence spectroscopy. The type of the side chain as well as the length of the flexible spacer influence the thermal and mechanical behavior of the synthesized polyethers. In all examined cases, the isotropization transition as well as the glass transition temperature show an odd−even effect depending on the spacer segment length. The polymers are soluble in common solvents and form free-standing films that combine high modulus (E‘) at room temperature with blue photoluminescence. High fluorescence quantum yield (φ = 0.82) was obtained for the polyethers studied, which is comparable to values reported in the literature for substituted poly(p-phenylenes). The type of the substitutent affects the maximum of the fluorescence peak, which is in the range 370−430 nm.

The purpose of this study is to assess the comprehensiveness of voluntary occupational health and safety (OHS) disclosures of large business entities. We devise a composite disclosure index, relying on well-established performance indicators, and focus on the information found in the sustainability reports of corporations pertaining to the oil and gas, chemical, airline, and construction industries, in an attempt to shed light on the current status and emerging trends in OHS reporting from a diverse group of business entities. The findings indicate that companies tend to place emphasis on their overall management approach to OHS, but fall short in reporting quantitative and qualitative information beyond the 'conventional' metrics of occupational injury rates. OHS issues within the supply chain and relevant monitoring systems/mechanisms in place are topics that are underreported, while OHS training programmes are an aspect that is inadequately analyzed in quantitative terms, being the least reported indicator in the sample reports. In contrast, companies from all four industries seek assurance for the OHS information that they report and place emphasis on the externally developed management standards/initiatives that they subscribe to, support, or have adopted. KEYWORDS corporate responsibility, occupational health and safety, sustainability reporting, sustainable development, voluntary disclosure

Polymeric films of rigid−flexible luminescent polyethers containing substituted quinquephenyl units in the main chain and films of their diluted blends in polypropylene have been uniaxially drawn at temperatures above their glass transition. Polarized micro-Raman measurements have been conducted to evaluate the molecular orientation of the drawn polymers and probe the effect of side chain length and type. The second, P 2, and fourth, P 4, moments of the segmental orientation distribution function determined from the analysis of Raman spectra indicate that the longer the side-chain length is, the higher the molecular orientation attained. At short side chain lengths, the presence of an oxygen link between the alkyl side chain and the aromatic segment resulted in a restricted polymer orientation. Polarized photoluminescence measurements have shown that neat photonic polyethers display low dichroic ratios despite the high orientability shown in Raman measurements. Diluted blends of photonic polyethers in polypropylene have shown commensurate high orientation moments in Raman and enhanced dichroic ratio in photoluminescence. The implication on the perspective of the studied polyethers to give materials with polarized blue light emission is evident.

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