Incorporation of a novel GO based cross-linker into the conventional poly(acrylic acid) hydrogel remarkably enhances the toughness and stretchability.

Bi-functional silica crosslinkers simultaneously enhance the mechanical strength and swelling capacity of the polyacrylic acid and polyacrylamide hydrogels.

Introduction of a two-dimensional graphene oxide-based crosslinker simultaneously improve the mechanical and self-healing properties of hydrogels by offering an interesting combination of covalent and reversible hydrogen bonds to polymer backbones.

Finding different strategies to incorporate functionalized nanocrystalline cellulose (NCC) in polymeric materials is a fascinating domain of current research. In this study, dialdehyde nanocrystalline cellulose (DANC) and dicarboxylated nanocrystalline cellulose...

Polylactic acid (PLA) biopolymer appears to provide environmental advantages over the petroleum-derived polymers but often ends up with limited applications owing to their poor mechanical performance and brittleness. Herein, we present a PLA polymer compatible graphene oxide (GO) based crosslinker with the intention of improving the mechanical properties. Lactic acid (LA) functionalized GO (GO-LA) crosslinker was prepared and had been crosslinked with the PLA chains through a one-step polycondensation reaction. The mechanical properties of the as-synthesized GO crosslinked PLA (GO-C-PLA) were investigated by compression tests and compared with neat PLA, and GO reinforced PLA (GO-PLA) with no crosslinking. With 0.3% of GO-LA crosslinker in GO-C-PLA, the compressive modulus increased by nine times compared to that of the neat PLA. The compressive strength also increased to 46 MPa, which was four times higher than the neat PLA. This strategy for improving the mechanical properties by introducing GO-based crosslinker can be used potentially for many polycondensation polymers and thus be useful for many high-performance applications.

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Hydrogels are emerging as one of the most attractive water‐containing polymeric materials for many biomedical and industrial engineering applications. Cellulose nanocrystals (CNC) are often used as filler material to overcome the drawbacks of conventional hydrogels. However, weak frictional interaction of CNC with the polymeric backbone of hydrogels in the presence of water has limited its applications. Herein, we report a mussel‐inspired preparation of a new bio‐based nano‐filler by grafting dopamine (DOPA) over the carboxylated cellulose nanocrystal (CCN), which has been obtained by oxidizing CNC extracted from sawdust. The swelling of polyacrylamide (PAM) hydrogels has been significantly suppressed by the incorporation of the modified filler. In contrast, the mechanical properties like Young's modulus, tensile strength, and toughness of PAM hydrogels increased remarkably indicating a strong interaction of CNC‐DOPA with the PAM chains. For instance, the tensile strength increased from 19 kPa for the CNC‐PAM to 39 kPa for the CCN‐DOPA‐PAM. Interestingly, insertion of only 1 % (w/w) CCN‐DOPA has led to the enhancement of the mechanical strength of PAM even more than that caused by the insertion of 4 % pristine CNC. The spectroscopic data along with the morphological analysis of the composite hydrogels suggest strong hydrogen bonding of DOPA moiety and the PAM backbone is responsible for this incredible improvement of the mechanical strength.