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One-pot syntheses and in situ ultrasonication have been optimized to generate tunable and highly hydrophobic 2,7-octadienyl-ether (ODE) cellulose nanofibrils (CNFs). Using only butadiene sulfone to serve as dual reaction medium and precursor to 1,3-butadiene (1,3-BD) for telomerization with cellulose hydroxyls, the OH-to-ODE conversion significantly improved from ca. 0.7 to 1.2, 1.8, 3.1, and 4.1 mmol of ODE/g-cellulose at 103-110 °C for 1-2 h. Ultrasonication was highly effective and versatile in the direct disintegration of ODE-cellulose (ODE-cell) in nonpolar organic solvents and plant oils into ODE-CNFs as well as pretreating cellulose for improved functionalization. Mixing 2 wt % in situ ultrasonicated 1.2 mmol of ODE/g-cell improved the modulus of polybutadiene six times and the strength of poly(styrene-b-isoprene-b-styrene) three times, whereas in situ ultrasonication of 1.8 mmol/g-cell directly with linseed oil at merely 0.07 wt % created holistic biobased hydrophobic cellulose paper to resist water penetration while also significantly improving the tensile strength. This optimized telomerization and streamlined in situ ultrasonication approach has presented a sustainable synthesis and processing strategy to generate highly hydrocarbon-compatible nanocelluloses previously unattainable.

Cellulose has been efficiently isolated from almond shell (AS) of a soft-shell Carmel variety by a two-step NaClO2 oxidation-KOH alkali protocol at over 35 % yield, then optimally TEMPO-oxidized and blended to yield 92 % and averagely 1.2 nm high (H), 5.2 nm wide (W), and 1.4 µm long (L) cellulose nanofibers (CNFs) with 58.6 % crystallinity and 1.3 mmole/g charge. With uniquely high 1167 L/H aspect ratio and 4.3 W/H lateral anisotropy, AS CNFs self-assembled into 1D fibers and 3D aerogels by freezing at − 196 °C and − 20 °C, respectively, then lyophilization as well as 2D films by air drying. All fibers were fully re-dispersable in water to individualized CNFs whereas aerogels were amphiphilic super-absorbents, absorbing slightly more hydrophobic chloroform than water, and films were hydrophilic on the surfaces and absorbed ca. three times more water than decane. The fully aqueous dispersible fibers, amphiphilic and water resilient aerogels, and organic resilient films are attributed to the interfacial associations of AS CNF driven by their uniquely high aspect ratio and cross-sectional anisotropy, demonstrating processing potential into versatile 1D to 3D materials.

Members of the family Competibacteraceae are common in wastewater treatment plants (WWTPs) designed for enhanced biological phosphorus removal (EBPR) and are putatively deleterious to the process of P removal. Their ability to accumulate large amounts of polyhydroxyalkanoates is also suggested to be of potential commercial interest for bioplastic production. In this study we have updated the 16S rRNA-based phylogeny of the Competibacter and the Plasticicumulans lineages. The former is delineated by 13 clades including two described genera; 'Ca. Competibacter' and 'Ca. Contendobacter'. The oligonucleotide probes used for detection of the family by fluorescence in situ hybridization (FISH) were re-evaluated and designed for coverage of these clades. Surveys of full-scale WWTPs based on 16S rRNA gene amplicon sequencing and FISH analysis indicate that a number of member clades always coexist, with their relative abundances varying substantially between and temporally within plants. The hypothesis that these differences are based on niche partitioning is supported by marked phenotypic differences between clades. An in-depth understanding of the ecology of the family requires further studies of the metabolism of individual clades in situ. The proposed phylogeny and FISH probes will provide the foundation for such studies.