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Intermolecular hydrogen bonds play an important role in the carboxymethyl chitosan/sodium alginate (CMCS/SA) composite spinning solution and composite fiber. In this study, we prepared a CMCS/SA composite fiber with various intermolecular hydrogen bonding (inter-MHB) proportions via a physical blending method. First, we studied quantitatively the effect of the inter-MHB proportions on the rheological property of the spinning solution and microstructure of the composite fiber. The apparent viscosity of the CMCS/SA composite solution decreased with the increase in the shear rate; however, it increased with the increase in the inter-MHB proportion. The crystallinity and surface roughness of the CMCS/SA composite fibers decreased with the inter-MHB proportion rising, as characterized by XRD and SEM analyses. Furthermore, we quantitatively constructed the relationship between the inter-MHB proportions and the performance of the CMCS/SA composite fibers. As the inter-MHB proportion increased, the tensile strength and modulus of the CMCS/SA composite fibers were enhanced significantly; the thermal stability of the CMCS/SA composite fibers was also improved slightly, as characterized by TGA; the hydrophilicity of the CMCS/SA composite fibers decreased slightly, as characterized by the contact angle test. Therefore, we can improve the viscosity, tensile strength, crystallization, thermal decomposition temperature, and hygroscopicity of CMCS/SA composite fibers by quantitatively regulating the inter-MHB proportions. This work also provides a theoretical and application basis for the study of related composite systems and fibers. [ABSTRACT FROM AUTHOR]

Complexation between a triptycene-derived macrotricyclic host and paraquat derivative and different polycyclic aromatic hydrocarbons in the solid state was investigated in detail. It was found that through multiple π–π, C–H…π and C–H…O hydrogen bonding interactions, four new kinds of quaternary complexes with “Russian doll”-like capsule structures in different complexation modes can be obtained. Furthermore, the complexes could self-assemble into linear supramolecular arrays, and 2D grid-like structures. [ABSTRACT FROM AUTHOR]

A hydrogen-bonded organic framework (HOF) was constructed by avoiding potential π–π stacking of building blocks with robust and non-coplanar triptycene-based modules. The tailored-fitting interactions were demonstrated by the adsorption of fullerene with a concentration enrichment of ∼420 times in the pores. [ABSTRACT FROM AUTHOR]