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Functionalized monomers are of utmost importance in producing new polymers and smart materials. Herein, a two-step approach involving heterogeneous catalysis was developed to produce a functionalized monomer (2-vinylfuran) from bio-based furfural, giving an overall yield of 89%. Economic analysis suggests that this facile approach incurs much lower costs, and its practicality improves the availability of 2-vinylfuran. This is due to the delicate structure of the optimized 4Na5Ce/SiO2, where Na species are present at the oxygen vacancies of the ceria that protect the catalyst structure from collapse, and the catalyst consequently displays excellent performance. Density functional theory (DFT) calculations revealed that the reaction occurs on the Na and Ce species. The adsorption of a furan group onto Na led to side reactions, which were suppressed in the presence of Ce, resulting in higher selectivity. Finally, a polymer based on 2-vinylfuran was prepared, which shows good surface properties and thermodynamic stability. [ABSTRACT FROM AUTHOR]

Synthetic rubbers fabricated from 1,3-butadiene (BD) and its substituted monomers have been extensively used in tires, toughened plastics, and many other products owing to the easy polymerization/copolymerization of these monomers and the high stability of the resulting material in manufacturing operations and large-scale productions. The need for synthetic rubbers with increased environmental friendliness or endurance in harsh environments has motivated remarkable progress in the synthesis of BD and its substituted monomers in recent years. We review these developments with an emphasis on the reactive routes, the products, and the synthetic strategies with a scaling potential. We present reagents that are primarily from bio-derivatives, including ethanol, C4 alcohols, unsaturated alcohols, and tetrahydrofuran; the major products of BD and isoprene; and the by-products, activities, and selectivity of the reaction. Different catalyst systems are also compared. Further, substituted monomers with rigid, polar, or sterically repulsive groups, the purpose of which is to enhance thermal, mechanical, and interface properties, are also exhaustively reviewed. The synthetic strategies using BD and its substituted monomers have great potential to satisfy the increasing demand for better-performing synthetic rubbers at the laboratory scale; the laboratory-scale results are promising, but a big gap still exists between current progress and large scalability. [ABSTRACT FROM AUTHOR]