Pluronic F127 diacrylate (F127DA) micelle-crosslinked methacrylated hyaluronic acid (MeHA) hydrogel with low-swelling and strong compressive properties was successfully synthesized for the regeneration of cartilages in vivo.

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The morphological collapse of pure biomassbased carbon fibers is the main challenge restricting its development. Inspiration comes from nature that cellulose and lignin in natural trees are linked by covalent-bonds, leading to good extensibility and stability of wood. In this work, an effective strategy is presented to connect lignin and celluloseacetate by covalent-bond to obtain a novel carbon fiber precursor material. Isophorone diisocyanate was used as a chemical modifier to successfully connect lignin and celluloseacetate through a covalent-bond, which is formed by the urethane reaction of isocyanate group and hydroxyl group. With the introduction of covalent-bond connection, the precursor fibers exhibit a large molecular weight, uniform molecular weight distribution, excellent thermal stability, and good spinnability. After thermo-stabilization and carbonization, the pure biomass-based carbon fibers are successfully prepared. The results of SEM, BET, tensile test, and electrochemical properties test indicate that the covalent-bond connection effectively maintains morphology of fiber, which plays a key role for increasing the strength and the energy storage capacity of carbon fibers. The pure-biomass-based carbon fibers show promise for the production of high-quality, green, and cost reduced carbon fibers.

Bimetallic metal-organic frameworks (MOFs) possess two different metal ions as nodes in their molecular frameworks. They are prepared by either using one-pot syntheses wherein different metals are mixed with suitable...

The effects of lignin chemical structures on the quality of lignin-based carbon fibers are still not clear. For this reason, we address the challenge by using a simple acid precipitation method to separate and purify lignin and study the effects of physicochemical characteristics of fractionated lignin on the properties of lignin-based CFs. The precipitation carried out by sequential acidification at different pH levels (10, 8, 6, 4, and 2) is indeed effective in obtaining fractionated lignin samples with different chemical structures, including molecular weights, units’ composition ratios, and polydispersity indexes (PDIs). All the fractionated lignin samples are respectively blended with polyacrylonitrile at the ratio of 1:1 (w/w) and electro-spun into fibers. Results suggest that a fractionated lignin sample with a large molecular weight, low PDI, and strong thermal stability can produce carbon fibers with excellent performance, such as good spinnability, high crystallization, and mechanical strength.

A simple low-energy method to fabricate lignin-based carbon fibers with excellent mechanical properties via electrostatic spinning.

In order to optimize the use of residues of enzymatic hydrolysis of corn stalk (REHCS) and explore the low‐cost and sustainable raw material substitute for carbon fibers, three types of lignin samples were extracted from REHCS by various extraction methods, and then they were converted into carbon fibers (CFs) by electrospinning, thermostabilization, and carbonization under the same process conditions. The microstructure and mechanical properties of the three types of carbonized fibers were different. The CFs from the ethanol organosolv lignin were actually smooth and brittle carbon films. The CFs from the formic acid/acetic acid organosolv lignin had microscopic pores, causing poor mechanical properties. Comparatively, the CFs from the alkaline lignin demonstrated preferable microstructure and mechanical properties. The reasons for the differences were analyzed by characterizing the lignin samples, precursor fibers, and resultant CFs. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45580.

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