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Ítem Tunable polyesterification of xylitol: from linear to crosslinked structures(John Wiley and Sons Ltd, 2017-04-01) Benitez, RicardoThe copolymerization by condensation chemistry of succinic acid and xylitol, a byproduct from the sugarcane and alcohol industry, is reported. Two methodologies were studied concerning succinic acid, with and without carboxylic acid activation, yielding crosslinked and linear low molecular weight polymers, respectively. All polymerizations were carried out at reaction times in the range from 36 to 80 h, with a molar mass ratio of 1:1 and 1:3. Linear and crosslinked polyesters were analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, DSC and TGA, and structural characterization was carried out by Fourier transform infrared spectroscopy and NMR. © 2016 Society of Chemical Industry. © 2016 Society of Chemical IndustryÍtem Acyclic diene metathesis polymerization: History, methods and applications(Elsevier Ltd, 2017-06-01) Caire da Silva, LucasAcyclic Diene Metathesis (ADMET) polymerization was established decades ago and has since developed into a robust and reliable technique. A wide range of different, new materials exhibiting unique properties has been produced via ADMET polymerization since its development. This versatile technique allows, through the right combination of monomer design and choice of catalyst, the synthesis of various functional polymers in addition to a precise control over primary structure. Systematic studies on precise ADMET polymers have greatly contributed to a better understanding of how branch identity and its distribution along the polymer backbone affect the thermal/electronic properties, crystallization, molecular dynamics and morphology of different materials. This article presents an extensive review of how ADMET started, the mechanism that underlies the structural features of ADMET polymers and the different strategies and techniques that have been developed over the years to overcome common synthetic challenges. Monomer synthesis methods are also discussed in detail, providing an important overview of the limitations and advantages of using ADMET as a polymerization technique. Many examples are given of functional ADMET polymers that have been developed by research groups all over the world. © 2016 Elsevier B.V.