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Natural polymer materials have attracted great attention in the field of hemostasis because of their wide range of source, nontoxicity, hydrophilicity, and air permeability. In the present study, two natural polymers composed of carboxymethyl chitosan (CMCS) and sodium carboxymethylcellulose (CMCNa) plus γ-(2,3-epoxypropoxy) propytrimethoxysilane (KH560) that serves as a crosslinking agent were selected to synthesize a capillary-mimicking composite hemostatic (CCK) sponge with a low density, interconnected microchannel architecture, suitable mechanical strength, high resilience, and ultrastrong liquid absorption capacity. The introduction of a large number of hydrophilic carboxymethyl functional groups and the design of capillary-mimicking structures formed by the ice segregation-induced self-assembly (ISISA) process endowed the CCK sponges with an ultrastrong liquid absorption capacity, which significantly enhanced the hemostatic ability of the materials. Both in vivo and in vitro hemostatic experiments confirmed the potential of the CCK sponges to achieve rapid hemostasis. Additionally, cytotoxicity and hemolysis assays showed that the CCK sponges exhibited good biocompatibility and hemocompatibility. The possible hemostatic mechanism was also discussed in this study. In conclusion, the capillary-mimicking hemostatic sponge exhibits a high potential to induce rapid hemostasis in prehospital emergency and clinical settings. STATEMENT OF SIGNIFICANCE: In the present study, an oriented composite hemostatic (CCK) sponge with a capillary-mimicking structure formed by the ice segregation-induced self-assembly (ISISA) process was designed and used to achieve rapid hemostasis. The unique aligned microchannel structure of the sponge exhibited an ultrastrong capillary-mimicking action and endowed the prepared CCK hemostatic sponge with a strong liquid absorption capacity. By changing the proportion of raw materials, we could modify the unique capillary-mimicking structure with aligned microchannels. Two natural polymer-based materials with abundant hydrophilic groups were chosen to prepare the CCK sponge to fully utilize the characteristics of this structure. The oriented natural polymer-based porous sponge with capillary-mimicking microchannels exhibited a strong hemostatic ability in both in vivo and in vitro tests. The results showed that the CCK sponge with the capillary-mimicking structure has a high potential to achieve rapid hemostasis.

Smart response hydrogel has a broad application prospect in human health real-time monitoring due to its responses to a variety of stimuli. In this study, we developed a novel smart hydrogel dressing based on conductive MXene nanosheets and a temperature-sensitive PNIPAm polymer. γ-Methacryloxypropyltrimethoxysilane (KH570) was selected to functionalize the surface of MXene further to improve the interface compatibility between MXene and PNIPAm. Our prepared K-M/PNIPAm hydrogel was found to have a strain-sensitive property, as well as a respond to NIR phase change and volume change. When applied as a strain flexible sensor, this K-M/PNIPAm hydrogel exhibited a high strain sensitivity with a gauge factor (GF) of 4.491, a broad working strain range of ≈250%, a fast response of ∼160 ms, and good cycle stability (i.e., 3000 s at 20% strain). Besides, this K-M/PNIPAm hydrogel can be used as an efficient NIR light-controlled drug release carrier to achieve on-demand drug release. This work paved the way for the application of smart response hydrogel in human health real-time monitoring and NIR-controlled drug release functions.

To continue the search for novel series of ferroelectric liquid crystals, an additional two series of compounds, C S(+)-4-[(2-methylbutyl)phenyl]4′-trans-n-alkylcyclohexyl) benzoates and D S(+)-4-[(4-methylhexanoyl)phenyl]4′(4″-trans-n-alkylcyclohexyl) benzoates, where alkyl = C5-C6 are reported in this paper. Their mesomorphic properties have been characterized by optical textural observations and DSC. Some of these compounds show a C-S*C-SA-N*-I phase transition sequence. The effects of the alkyl chains on transition temperatures and optically active terminal groups on phase behaviour are discussed.

In this work, twelve compounds: 5(+)-4-[(2-methylbutyloxycarbonyl)phenyl]4′-(4″-trans-n-alkylcyclohexyl)benzoates; S(+)-4-[(2-methylbutyloxy)phenyl]4′-(4″-trans-n-alkylcyclohexyl)benzoates, where alkyl = C5-C10, were synthesized. The effect of the alkyl chains on liquid crystal transition temperatures of two homologous series prepared has been investigated systematically. The mesomorphic properties are studied by DSC and Polarizing Microscopy. Chiral smectic C and chiral nematic mesophases, as well as a smectic A mesophase, in several cases, were observed.

Three diaza-18-crown-6 carrying aryl ester structural unit were synthesized and shown to nematic liquid crystalline properties. The influence of the molecular structure on liquid crystalline properties was studied. It has been found that whether the complexes display liquid crystalline properties depends upon structure of anions. The influence of doping inorganic salt on the clear point was also studied.

The experimental investigation of the induced smectic phase (ISP) phenomenon in the binary system of the homologous series of alkyl cyano phenylcyclohexane (PCH) and 4-n-hexyloxyphenyl 4'-pentyl benzoate ester (5.0.6) is reported. The phase transition temperatures were determined by differential scanning calorimetry and the optical textures were observed through a polarizing microscope in conjunction with a hot-stage. We found that the ISP-effect on equimole mixture of PCH and 5.0.6 increased sharply with the increasing of the length of terminal alkyl chain. By comparing PCH with Cyanobiphenyl (CBP) we also found that the ISP-effect was influenced by molecular framework.