Soil microbiomes mediate degradation of vinyl ester-based polymer composites

Polymer composites are attractive for structural applications in the built environment due to their lightweight and high strength properties but suffer from degradation due to environmental factors. While abiotic factors like temperature, moisture, and ultraviolet light are well studied, little is known about the impacts of naturally occurring microbial communities on their structural integrity. Here we apply complementary time-series multi-omics of biofilms growing on polymer composites and materials characterization to elucidate the processes driving their degradation. We measured a reduction in mechanical properties due to biologically driven molecular chain breakage of esters and reconstructed 121 microbial genomes to describe microbial diversity and pathways associated with polymer composite degradation. The polymer composite microbiome is dominated by four bacterial groups including the Candidate Phyla Radiation that possess pathways for breakdown of acrylate, esters, and bisphenol, abundant in composites. We provide a foundation for understanding interactions of next-generation structural materials with their natural environment that can predict their durability and drive future designs.

“The behavior of some terpolymers as lubricating oil additives”

In this work, we prepared different alkyl acrylates by esterifying acrylic acid with different alcohols (decanol, dodecanol, hexadecanol and octadecanol). Anilimide was then produced by the reaction of aniline with maleic anhydride. Different teropolymers were prepared by polymerization reaction of anilimide, different alkyl acrylate esters and olefins in different ratios. The thermal stability of the prepared terpolymers was measured by thermal gravimetric analysis which demonstrated a high thermal stability. The polymers were degraded above 500 °C. The rheology behavior shows shear-thinning, it approaches the ideal Newtonian behavior in case of polymer (C). The prepared terpolymers succeeded in raising the viscosity index of oil to 118 in case of polymer (C) and decreasing the pour point of oil to -12 in case of polymer (E).

Microbial dark matter driven degradation of carbon fiber polymer composites

Polymer composites have become attractive for structural applications in the built environment due to their lightweight and high strength properties but can suffer from degradation due to environmental factors. While impacts of abiotic factors like temperature and moisture are well studied, little is known about the influence of naturally occurring microbial communities on their structural integrity. Here we apply complementary time-series multi-omics of biofilms growing on polymer composites and materials characterization to elucidate, for the first time, the processes driving their degradation. We measured a reduction in mechanical properties due to molecular chain breakage and reconstructed 121 microbial genomes to describe microbial diversity and pathways associated with their degradation. The composite microbiome is dominated by four bacterial groups including the Candidate Phyla Radiation that possess pathways for breakdown of acrylate, esters, and bisphenol, abundant in composites. Overall, we provide a foundation for understanding interactions of next-generation structural materials with their natural environment that can predict their durability and drive future designs.

Synthesis of a Chiral Auxiliary Family from Levoglucosenone and Evaluation in the Diels–Alder Reaction

A new family of chiral auxiliaries has been developed based on the lignocellulosic biomass pyrolysis product levoglucosenone. A promising single stereoisomer with an alcohol and π-stacking phenyl substituents was prepared in excellent yield in two steps from di­hydrolevoglucosenone without chromatography on >50 g scale. Acrylate esters prepared from the auxiliaries underwent diastereoselective Lewis acid promoted Diels–Alder reactions with cyclopentadiene (­endo/exo 98:2, endo d.r. up to 98:2), dimethylbutadiene (d.r. 93:7), and isoprene (d.r. > 98:2)