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The synthesis of aliphatic, degradable polyesters based on biobased alditols was investigated. Mannitol and dulcitol were employed as biobased building blocks for the synthesis of aliphatic polyesters in combination with sebacoyl chloride. In order to achieve optimal control over the macromolecular architecture of the polymer, multifunctional monomers were converted to bifunctional species through a straightforward protection strategy. Bifunctional di-O-isopropylidene derivatives were synthesized starting from mannitol and dulcitol in a one-step procedure and exploited as monomers to yield linear poly(mannitol sebacate) (PMS) and poly(dulcitol sebacate) (PDS) derivatives. The use of a bifunctional monomer allowed an optimal control over the macromolecular architecture and the synthesis of PMS and PDS-based polyols. These polyols were then employed as initiators for the synthesis of PLA-based copolymers. Two different concentrations of PMS and PDS were tested and the related effects investigated, regarding the molecular weight and thermal properties of the resulting PLA-based copolymers. Deprotection of the isopropylidene moieties on the polyol backbone was then evaluated in order to determine the influence of liberation of free OH- groups on the wettability of the materials. Finally, degradation tests were performed in different aqueous environments, showing the influence of PMS and PDS on the degradation rate of PLA-based materials. The synthesis of aliphatic, degradable polyesters based on biobased alditols was investigated., QC 20240513

Poly(3,4-ethylenedioxythiophene) (PEDOT) plays a key role in the field of electrically conducting materials, despite its poor solubility and processability. Various molecules and polymers carrying sulfonic groups can be used to enhance PEDOT’s electrical conductivity. Among all, sul-fonated polyarylether sulfone (SPAES), prepared via homogenous synthesis with controlled degree of sulfonation (DS), is a very promising PEDOT doping agent. In this work, PEDOT was synthesized via high-concentration solvent-based emulsion polymerization using 1% w/w of SPAES with different DS as dopant. It was found that the PEDOT:SPAESs obtained have improved solubility in the chosen reaction solvents, i.e., N, N-dimethylformamide, dimethylacetamide, dimethyl sulfoxide, and N-methyl-2-pyrrolidone and, for the first time, the role of doping agent, DS and polymerization solvents were investigated analyzing the electrical properties of SPAESs and PEDOT:SPAES samples and studying the different morphology of PEDOT-based thin films. High DS of SPAES, i.e., 2.4 meq R-SO3− × g−1 of polymer, proved crucial in enhancing PEDOT’s electrical conductivity. Furthermore, the DMSO capability to favor PEDOT and SPAES chains rearrangement and interaction results in the formation of a polymer film with more homogenous morphology and higher conductivity than the ones prepared from DMAc, DMF, and NMP. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

1,3-Dioxolan-4-one (DOX) chemistry was explored for production of "one-pot" biobased polyester thermosets. DOX monomer was first functionalized by naturally occurring eugenol to introduce a structural element, which could induce cross-linking reaction through cationic polymerization of the double bond. The feasibility of polymerizing DOX monomers bearing bulky side groups was proven by model phenol-substituted DOX monomer (PhDOX). Once the reaction was shown to be effective, the same protocol was applied to eugenol-substituted monomer (EuDOX). A brief screening of the optimal catalyst concentration was performed, to obtain a highly cross-linked product. The synthesized thermoset showed good thermal resistance and high mechanical strength probably due to the rich aromatic content. The obtained thermoset was further subjected to microwave-assisted hydrothermal degradation test, which demonstrated complete recyclability to water or methanol soluble products. NMR and matrix-assisted laser desorption/ionization-mass spectroscopy analyses of the obtained degradation products unveiled the structure of the thermoset, strongly indicating that the polymerization of eugenol-functionalized DOX monomer resulted in polylactide-like chains connected with aromatic aliphatic segments resulting from the reaction of the eugenol double bonds. The presence of free hydroxyl and carboxyl groups sheds light on the mechanism behind the observed shape-memory and self-healing properties., QC 20190108