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Improving the sustainability of polymer networks is a crucial challenge in polymer science due to their important role in industry. Their traditional syntheses conflict with several principles of green chemistry as the employed monomers are petroleum‐based, their production involves the use of toxic reagents, and their permanently cross‐linked structures impede their chemical recycling and reshaping. The development of vitrimers represents a unique solution to address the issue of polymer network end‐of‐life by enabling reprocessability while maintaining good thermomechanical properties and solvent resistance. Although over the last decades biomass has proved to be an excellent feedstock for the production of permanently cross‐linked polymers, the field of biobased vitrimers is still in its infancy. In this review, a comprehensive overview of vitrimers synthesized from biobased monomers is presented. The emphasis is set on the compatibility of the biomass structure with the nature of the dynamic covalent chemistry, as well as the sustainability of the synthetic approaches. Implementing renewable feedstocks and recyclability in the production of polymer networks paves the way for the development of the next generation of sustainable materials. [ABSTRACT FROM AUTHOR]

The synergy of multicomponent reactions (MCRs) and metathesis chemistry is applied for the synthesis of bio‐based functional isosorbide polymers (i.e., polyesters) decorated with α‐acyloxy amide motif. The chemical structure of the polyesters that are not accessible by any other conventional methodologies is characterized in‐depth via nuclear magnetic resonance, size‐exclusion chromatography, and attenuated total reflectance infrared spectroscopy. It is also observed that the "biomass‐derived" carbon % of the polymers varied between 66.2 and 76.9. Moreover, the thermal properties of the novel isosorbide‐based polymers are investigated via thermogravimetric analysis and differential scanning calorimetry, revealing that the polymers are in the amorphous state, identified by the glass transition temperature (Tg) values below the human body temperature. The mechanical properties and the biocompatibility of the functional novel polyester derivative with the highest "biomass‐derived" carbon % are evaluated via dynamic mechanical analysis and cytotoxicity test. The exemplary polymer is biocompatible with chondrocyte cells in the conditions used in the tests. In summary, the complementary nature of isosorbide derivatives with MCRs and metathesis chemistry is utilized to illustrate the potential utility of isosorbide as a building block for polymers with prospective biomedical application (namely, as novel cartilage materials). [ABSTRACT FROM AUTHOR]

Three acrylate monomers featuring different side‐groups are synthesized in yields up to 94% in a one‐pot procedure using the versatile Passerini‐three‐component reaction. The procedure for their miniemulsion polymerization into polymeric particles with tunable sizes is established. Ethylene glycol dimethacrylate is introduced as comonomer to induce crosslinking and enable the production of microgels. Besides the shelf life of the miniemulsions, the dependence of the particle size on the concentration of the surfactant (sodium dodecyl sulfate) and the crosslinker, as well as the sonication amplitude and time, is investigated. The particle size of the collapsed microgels range from 21 to 91 nm. The swelling of the microgels in organic solvents is studied. [ABSTRACT FROM AUTHOR]

Polyurethanes exhibit excellent coating properties for many applications. Facing the continuous growth of the polyurethane coating market, in the last few years many scientists have addressed the safety and sustainability of their production. This paper highlights the efforts that have been pursued in this direction from both the academic and industrial perspectives and covers aspects ranging from the substitution of petroleum‐based monomers by biobased equivalents to the development of novel synthetic pathways for the production of polyhydroxyurethanes. © 2018 Society of Chemical Industry Towards greener polyurethane coatings. [ABSTRACT FROM AUTHOR]

The good availability and high degree of functionalization possibilities of plant oils entitles them to be one of the most intensively studied renewable resources, especially in polymer science. However, in line with the principles of green chemistry, the use of renewable resources should be accompanied with catalytic procedures, comparably less or non-toxic chemicals, as well as reduction of waste and energy consumption to achieve an overall sustainable process. In this review, these aspects are addressed using the example of plant oil-based thermoset materials, which bear the advantage, in terms of sustainability, of not requiring a separation or purification step prior to polymerization. The direct homopolymerization of plant oils, as well as copolymerization, exclusively with other renewable resources, are highlighted. The sustainability of the synthesis of a broad range of thermosets including epoxy resins, polyurethane networks, polybenzoxazines and unsaturated polyesters is discussed. [ABSTRACT FROM AUTHOR]

Taking advantage of the structural diversity of different biomass resources, recent efforts were directed towards the synthesis of renewable monomers and polymers, either for the substitution of petroleum-based resources or for the design of novel polymers. Not only the use of biomass, but also the development of sustainable chemical approaches is a crucial aspect for the production of sustainable materials. This review discusses the recent examples of chemical modifications and polymerizations of abundant biomass resources with a clear focus on the sustainability of the described processes. Topics such as synthetic methodology, catalysis, and development of new solvent systems or greener alternative reagents are addressed. The chemistry of vegetable oil derivatives, terpenes, lignin, carbohydrates, and sugar-based platform chemicals was selected to highlight the trends in the active field of a sustainable use of renewable resources. [ABSTRACT FROM AUTHOR]

A novel and straightforward one-pot multicomponent polycondensation method was established in this work. The Biginelli reaction is a versatile multicomponent reaction of an aldehyde, a β-ketoester (acetoacetate) and urea, which can all be obtained from renewable resources, yielding diversely substituted 3,4-dihydropyrimidin-2(1H)-ones (DHMPs). In this study, renewable diacetoacetate monomers with different spacer chain lengths (C3, C6, C10, C20) were prepared via simple transesterification of renewable diols and commercial acetoacetates. The diacetoacetate monomers were then reacted with renewable dialdehydes, i.e., terephthalaldehyde and divanillin in a Biginelli type step-growth polymerization. The obtained DHMP polymers (polyDHMPs) displayed high molar masses, high glass transition temperatures ( Tg) up to 203 °C and good thermal stability ( Td5%) of 280 °C. The Tg of the polyDHMPs could be tuned by variation of the structure of the dialdehyde or the diacetoacetate component. [ABSTRACT FROM AUTHOR]

Nowadays, the synthesis of (semi)aromatic polymers from lignin derivatives is of major interest, as aromatic compounds are key intermediates in the manufacture of polymers and lignin is the main source of aromatic biobased substrates. Phenols with a variety of chemical structures can be obtained from lignin deconstruction; among them, vanillin and ferulic acid are the main ones. Depending on the phenol substrates, different chemical modifications and polymerization pathways are developed, leading to (semi)aromatic polymers covering a wide range of thermomechanical properties. This review discusses the synthesis and properties of thermosets (vinyl ester resins, cyanate ester, epoxy, and benzoxazine resins) and thermoplastic polymers (polyesters, polyanhydrides, Schiff base polymers, polyacetals, polyoxalates, polycarbonates, acrylate polymers) prepared from vanillin, ferulic acid, guaiacol, syringaldehyde, or 4-hydroxybenzoic acid. [ABSTRACT FROM AUTHOR]

Review: [102 refs. [ABSTRACT FROM AUTHOR]