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A low-shrinkage and viscosity-reducing polycarboxylate superplasticizer was synthesized with maleic anhydride (MAH), diethylene glycol monobutyl ether, and methoxypoly (ethylene glycol) methacrylate (MPEGnMA). The surface tension, early shrinkage, cement paste performance, and application performance of concrete made with the synthesized water-reducing admixture were tested. A series of experiments were conducted to determine the optimal range of plastic viscosity coefficients for producing high-quality, fair-faced concrete with minimal surface defects. These experiments utilized both the synthesized water-reducing admixture alone and in combination with other water-reducing agents. The results showed that the synthesized water-reducing admixture had an ideal molecular structure, as confirmed by the GPC spectrum. When added to an aqueous solution, it reduced the surface tension from 72.47 mN/m to 30.56 mN/m. The 72 h shrinkage value of concrete was reduced by 20.6% compared with that of the conventional control group, effectively reducing shrinkage and adjusting the viscosity of the concrete mixture. Additionally, the influence of the plastic viscosity coefficient on the apparent voids in fair-faced concrete was investigated. This study revealed that when the plastic viscosity coefficient was between 5 and 10 Pa·s, the apparent void grade of the fair-faced concrete was simultaneously excellent and good. This water-reducing admixture helped prevent surface cracking and voids in fair-faced concrete, making it a suitable choice for producing high-quality fair-faced concrete surfaces. [ABSTRACT FROM AUTHOR]

Abstract: Although PEGylation is a potential approach to prolong the half-lives and reduce the dosing frequency of therapeutic proteins, conjugation behaviors of polymer have pivotal effects on the remaining bioactivities of the derivatives. In this study, the PEGylation strategy of recombinant human interleukin-1 receptor antagonist was investigated. The random conjugation of polyethylene glycol to amino groups on the protein resulted in a severe loss of activity and only retained 9.8% of the activity. In contrast, the PEGylation at the thiol groups had moderate effects on the bioactivity of protein and 40% of activity was conserved. The results suggested that the thiol-target PEGylation was more beneficial for IL-1ra. [Copyright &y& Elsevier]

The preparation of high lignin content hydrogels with good mechanical and multifunctional properties remains a huge challenge. In this study, a novel polymer-nanoparticle hydrogel was developed by a covalent crosslinking strategy, which not only preserved the characteristics of nanoparticles but also gives them good mechanical properties. Herein, lignin-silver nanoparticles (Lig-Ag NPs) were prepared from industrial lignin starting material and crosslinked into hydrogel with poly(ethylene glycol) diglycidyl ether. The obtained hydrogel (Lig-Ag NPs/PEG, LANP) exhibited good mechanical properties (elongation at break 53%, tensile strength 94.67 kPa, toughness 277.32 kJ m−3), adhesiveness, conductivity, pressure- and pH-stimuli-responsiveness, which benefited from the appropriate degree of crosslink, the generated catechol groups and redox-active quinone/semiquinone free radicals from Lig-Ag NPs. These functional properties can also be tuned by the contents of Lig-Ag NPs. Based on the above properties, a LANP sensor was assembled and showed good application for pressure- and pH-monitoring. This work provides a green and facile strategy of lignin valorization towards new multi-functional and smart applications. • Lignin-silver nanoparticles/PEG hydrogel (LANP) was fabricated by covalent bonds. • The mechanical properties of LANP can be tuned and improved by Lig-Ag NPs. • LANP has good adhesiveness, pressure sensitivity, and pH-stimuli-responsiveness. • LANP showed good application for pressure- and pH-monitoring. [ABSTRACT FROM AUTHOR]