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3-(4-Hydroxyphenyl)propanoic acid, so-called phloretic acid (PA), is a naturally occurring phenolic compound which can be produced by the hydrogenation of p-coumaric acid or synthesized from phloretin, a by-product of apple tree leaves. It is explored herein as a renewable building block for enhancing the reactivity of –OH bearing molecules towards benzoxazine (Bz) ring formation instead of phenol. PA is used to bring phenolic functionalities by its reaction with model molecules (ethylene glycol, as well as two polyethylene glycol molecules with molar masses corresponding to 400 g·mol−1 and 2000 g·mol−1) via solvent-free Fischer esterification. These phenolic groups are further reacted with a bio-based amine (furfurylamine) to form almost 100% bio-based benzoxazine end-capped molecules. Very interestingly, the whole synthesis of Bz monomers from PEG400 and PEG2000 does not require a solvent or purification, and their polymerization led to a set of materials with thermal and thermo-mechanical properties suitable for a wide range of applications. These results show that renewable phloretic acid is a sustainable alternative to phenol to provide easily the specific properties of benzoxazine to aliphatic –OH bearing molecules or macromolecules. This novel approach paves the way towards a multitude of applications given the large number of –OH bearing compounds in materials science. [ABSTRACT FROM AUTHOR]

It is well established that the chemical structure of surfactants used to promote the dispersion of clay minerals in polymers plays a major role in clay polymer nanocomposites preparation. However, much less explored is the incorporation of reactive surfactants capable of covalently grafting to monomers and polymer chains. In this work, the effect of the reactivity degree of bio-based surfactants onto the exfoliation of montmorillonite in epoxy is evidenced. For this purpose, 3 surfactants were prepared from a derivative of Cardanol, incorporating reactive groups: N(CH 3 ) 2 , NH 2 or two NH 2 functions. In each case, the organomodification of the clay mineral results in a similar interlayer space increase. Combined chemical derivatization and MALDI-TOF/MS was used to evidence the differences of the residual reactivity of the intercalated surfactants. Finally each organomodified clay mineral was used for the preparation of epoxy nanocomposites. Interestingly, for the most reactive surfactant, X-ray diffraction analysis evidenced a fully exfoliated structure while semi-exfoliation or intercalated structure was found for the less reactive surfactants. [ABSTRACT FROM AUTHOR]

Highlights: [•] In this paper, we study the adhesive, water resistance and thermo-mechanical properties of a bio-based DGEBA substitution candidate issued from Cardanol. [•] Bio-based networks outperformed the conventional epoxy in terms of adhesion and water uptake, representing interesting alternatives for applications close to ambient temperature. [•] An unconventional relationship between water uptake by the biobased adhesive and property loss due to plasticization was uncovered. [Copyright &y& Elsevier]

The article presents an overview on legally protected freedom of speech in labour union gatherings. It highlights concerns related to pickets or strikes act of trade unions regarding self expression in which law restricts free speech in labour unions that are governed by rules of law. It raises concerns regarding wage-earner to take action against the legal obligation to participate in union expenses.