Designed Monomers and Polymers最新文献

Rigid polyurethane foam (RPUF) as a filling material that can enhance the crashworthiness of thin-walled tubes. GO-HGMS hybrid was prepared by solution blending of graphene oxide (GO) and hollow glass microspheres (HGMS). The effect of the composite on the compression properties of RPUF was investigated. The GO-HGMS hybrid was characterized by fourier transform infrared spectroscopy (FTIR), x-ray diffraction(XRD), and scanning electron microscopy (SEM). The compression test and microstructure results show that the best compression performance and the largest apparent density of the composite foam were obtained when the hybrid content was 4 wt %. In addition, the compression test results of empty tubes (ET) and foam-filled tubes (FFT) under lateral load indicate that the combination of lightweight foamed material and thin-walled tube improves the stability of thin-walled tube deformation and the ability of the structure to resist deformation. GO-HGMS/RPUF as the filling material of thin-walled tube structure greatly improves the bearing capacity and energy absorption level of ET.

A flexible polyaniline/polyvinyl chloride (PVC) polymer conductive wire was prepared using flexible PVC polymer as the substrate by the swelling - in-situ polymerization method, the line-shaped dents were pressed on the substrate by the thermodynamic pre-deformation treatment technology. Based on the orthogonal test method, the effects of five main influencing factors - swelling time (A), swelling temperature (B), oxidation temperature (C), oxidation time (D), and oxidant concentration (E) - on the conductivity of the prepared polyaniline/PVC conductive wire was investigated. The results of the orthogonal array testing were subjected to range analysis and analysis of variance (ANOVA), and the influencing factors, in terms of significance, follow the order of swelling temperature, oxidation time, swelling time, oxidation temperature, and oxidant concentration, with the optimal factor-level combination being A₂B₂C₂D₂E₂, which led to a desirable conductivity up to 1.19 × 10^-1 S/cm. In addition, the influence of different conductive line size characteristics on the molecular structure, microstructure, and conductivity of polyaniline/PVC flexible conductive wire was further studied. On the microstructure, as the line width increases, the infrared absorption intensity ratio of the quinone ring and the benzene ring in the polyaniline/PVC conductive wires gradually approaches 1. The microstructure, as the line width of the polyaniline/PVC conductive wire increases, the formed polyaniline gradually changes from flakes and granules to fibrous strips and entangles with each other to form a spatial network structure. The conductivity of the wire increases with the increase of its width up to 1.48 × 10^-1 S/cm.

In this current experiment, by applying the mixed-ligand synthesis method, two coordination polymers (CPs) containing Co(II) were created triumphantly with reaction between 1,3-bis(1-imidazoly)benzene (mbib) and Co(II) salts with the aid of diverse carboxylic ligands, and their chemical formulae are [Co₃(opda)₃(mbib)₄(H₂O)₄]·2H₂O (1, H₂opda is 1,2-phenylenediacetic acid) and [Co(mpda)(mbib)]·H₂O (2, H₂mpda is 1,3-phenylenediacetic acid). The two compounds' magnetic performances suggest that between the adjacent metal ions, there present the antiferromagnetic coupling. The evaluation of their treatment activity against chronic subdural hematoma was carried out and the relevant mechanism was studied simultaneously. Firstly, before the treatment of compound, the chronic subdural hematoma was generated. Furthermore, the enzyme-linked immunosorbent assay detection kit was implemented and in hematoma capsule, the anti-inflammatory cytokines level and pro-inflammatory cytokines level was detected. Additionally, the cytotoxicity of compounds 1 and 2 on the normal human cells was determined with Cell Counting Kit-8 assay. Above all, we proved compound 1 decreased the pro-inflammatory cytokines content and increased the anti-inflammatory cytokines content in the hematoma capsule, which is much stronger than that of compound 2. Both compounds 1 and 2 showed no cytotoxicity on the normal human cells.

The preparation of liquid fluoroelastomers that are liquid with excellent mechanical properties remains a challenge. Here, we show a very straightforward method to produce liquid fluoroelastomers by introducing carborane. Carborane-terminated liquid fluoropolymer was synthesized by Steglich reaction of carboxyl-terminated liquid fluoropolymer and 1,7-bis (hydroxy)-carborane. The product is brown, viscous at room temperature and in the semi-solid state. On this basis, HDI Trimer was used as a curing agent to cure liquid fluoroelastomer. Thermogravimetric analysis of the cured products was carried out. The carbon residue rate of the cured product increased from 35% to 58% of the cured product. The results show that the addition of carborane structure can effectively improve the carbon residue rate of liquid fluoroelastomer. The tensile strength, elongation and shore hardness of the cured product were also examined, and the results show that the tensile strength of carborane modified liquid fluorine increased by 463% compared with that before modification, but the elongation at break was reduced by 42%, which was mainly due to the introduction of rigid structure of carborane. At the same time, the solvent resistance test results show that the introduction of carborane structure has little effect on the aviation kerosene resistance and organic solvent resistance of fluororubber, but it can improve its alkali resistance.

A new Cd(II) coordination polymer with the formula of {[(CH₃)₂NH₂][Cd₃(NH₂-bdc)₃(btz)(H₂O)]} _n (1 NH₂-H₂bdc = 2-aminoterephthalic acid, Hbtz = 1 H-benzotriazole) was produced and then it was structurally characterized through powder X-ray diffraction (PXRD), the analysis of X-ray single-crystal diffraction, along with elemental analysis (EA). The photocatalytic property investigations indicate that compound 1 exhibits good activity for photodegradation of methyl violet (MV) with 60.7% of MV removal in 40 min under room temperature. Furthermore, the assessment of the compound's treatment activity and nursing application values on the bacterial infection was conducted and its corresponding mechanism was also studied. Evaluation of the in vitro hemolysis of the compound was determined by measuring the degree of red blood cell lysis and hemoglobin release. The effect of new compounds on the relative proliferation rate of L-929 cells was measured by MTT assay. The ELISA detection kit showed that the compound could reduce the TNF-α and IL-1β content released into plasma. Next, the inhibitory activity of the compound on the bacterial survival gene expression was also proved with real-time RT-PCR. The hemolysis rate of the new compound to blood is 3.4%, which is less than the standard 5%, which is non-hemolytic reaction. The compound also has no obvious cytotoxicity and has good cell compatibility.

Electrospinning provides a versatile, efficient and low-cost method for the preparation of continuous nanofibres from various polymers. In this study, the polyhedral oligomeric silsesquioxanes (POSS) block copolymer was synthesized via atom transfer radical polymerization. The smooth fiber, porous fiber or hierarchically porous microspheres were prepared by electrospinning from POSS block copolymer, poly(vinylidene fluoride) (PVDF) and aluminium oxide (Al₂O₃). The influence of copolymer concentration, the ratio of the solvents, the diameter and concentration of the Al₂O₃ on the surface morphology were investigated. Porous fibers and porous microspheres were prepared by regulating the ratio of the solvents from the phase separation and breath figure methods. The dynamic behavior of the water droplet with the constant volume impacting on the electrospinning films were reported. The morphology evolution, restitution coefficient, the change of energy of the water droplets are examined. The droplet bounces several times on the superhydrophobic surface, while the droplet remains pinned and does not rebound when the contact angles was lower than 150°. On the other hand, the water droplets were splashed on the Al₂O₃ based electrospinning films. Finally, the mechanical properties of the electrospinning films were investigated.

Magnetic nanoparticles (MNPs) with safety, stability and excellent magneto-calorific effect are the precondition for the smart magnetic drug carriers' fabrication and controllable drug release at a specific target in clinical treatment. In this study, the drug release and magneto-calorific effect of two types of magnetic lipid microcapsules (MLMs) loading lipid-coated MNPs and uncoated MNPs respectively were compared deeply in experimental analysis and theoretical simulation. The simulation results revealed that almost same magnetic heat effect and temperature increasing exist between lipid-coated and uncoated MNPs, which was consistent with the experimental drug release results. Coating lipid on MNPs didn't affect the magnetic heat and heat transfer of the MNPs. Because of the heat transfer between MNPs and water, MLMs and water around, the temperature increasing of whole sample solution is lower than that of the MNPs themselves. Our results provide a reliable theoretical basis for the development of healthy, safe, and biocompatible drug delivery systems.

A Cu(II) coordination polymer with the composition of [Cu₂(L)₂(4,4'-bipy)₂]_n·2 n(ClO₄) (1, HL = 4-methyl-L-phenylalanine and 4,4'-bipy is 4,4'-bipyridine), was successfully obtained by the reaction of the mixed ligand of HL and 4,4'-bipy with Cu(ClO₄)₂ · 6H₂O under solvothermal condition. The as-synthesized compound not only has high thermal stability until 275°C but also excellent photocatalytic activity for the methyl blue solution degradation under the irradiation of ultraviolet light. Furthermore, the compound's treatment activity on the diabetes was determined and its relevant mechanism was also studied. The cytotoxicity or hemolysis toxicity (HC50) of the synthesized compound was also evaluated in this research.

A new type of superhydrophobic borneol-based polymeric coating has been prepared. The chemical composition of the polymer particles was analyzed by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy, which showed that the polymer did not contain fluorine, which can effectively avoid the cytotoxic risk of fluorine. By dynamic light scattering, scanning electron microscopy, and static contact angle measurement, the contact angle of the prepared coating gradually increased with increasing diameter of the polymer particles, and a superhydrophobic coating surface was finally obtained. Interestingly, after dissolving the superhydrophobic sample with tetrahydrofuran and making it a normal hydrophobic sample, the antiadhesion performance for E. coli was greatly reduced, and it could not effectively prevent E. coli adhesion. In addition, a long-term antiadhesion study of bacteria was performed. The superhydrophobic borneol-based polymer coating showed long-term resistance to E. coli adhesion. Therefore, the excellent antibacterial properties and cell compatibility mean that this series of polymer materials has great potential in the field of biomedicine.