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2-(diisopropylamino) ethyl methacrylate (DIPEMA) and glycidyl methacrylate (GlyMA) were used for the investigation of the redox-initiated reversible addition-fragmentation chain transfer (RAFT) dispersion polymerization, by using poly (ethylene oxide)-4-(4-Cyanopentanoic acid) dithiobenzoate (mPEG-CPADB) as the macro-chain-transfer agent (macro-CTA). The particle growth process study indicated that the particles changed from spheres to worms, and then to vesicles during the polymerization process. The degree of polymerization (DP) of the hydrophobic block P(DIPEMA-co-GlyMA) affected the particle morphology, particle diameter and molecular weight significantly. Pure polymeric vesicles could be obtained when DP was equal to or higher than 60, and with increasing of the DP of the hydrophobic block, the diameter and the molecular weight of the particles both increased.

Polypropylene (PP) composite materials were prepared through two molding methods of injection and compression molding, taking PP, FG as the matrix and thermal conductive filler. The effects of molding methods and FG content on the thermal conductivity of composite materials were studied, and the SEM, XRD, and thermal expansion properties of the materials were further analyzed. Results showed that thermal conductivity of the composite material increases with increasing of the FG content. When the FG content was 75 wt%, the average thermal conductivity of the composite materials prepared by injection molding and compression molding is 9.88 W·m-1·K-1 and 6.03 W·m-1·K-1, respectively. The axial thermal conductivity is 16.6 W·m-1·K-1 and 1.35 W·m-1·K-1, and the radial thermal conductivity is 5.88 W·m-1·K-1 and 26.9 W·m-1·K-1, respectively. In composite materials formed by injection molding, the flaky FG is mainly oriented vertically, while in compression molding, the flaky FG is mainly oriented horizontally.

A polyethylenimine adjuvant modified by mannose, which may be used in the study of vaccine adjuvant, was prepared in this paper. Its structure was characterized by infrared spectroscopy and its micromorphology was observed by transmission electron microscopy. A series of mannose-modified polyvinylimine were prepared according to the molar ratio of primary amine groups between mannose and polyvinylimine, and their storage stability was observed at 4°C. In addition, the cytotoxicity of modified and unmodified polyethylenimine was also tested, and the results showed that the modified polyethylenimine was less toxic than unmodified polyethylenimine.

Poly (lactic-co-glycolic acid) (PLGA) is a kind of medical polymer material with good biodegradability and histocompatibility, which is widely used in postoperative anti-adhesion materials. In this paper, PLGA microfiber membrane was successfully prepared with poly(lactic-co-glycolic acid) as the main material by electrospinning technology. The surface morphology, wettability, dimensional stability and mechanical properties of PLGA microfiber films were characterized by scanning electron microscopy (SEM) and tensile testing machine. The results show that the average diameter of the prepared PLGA fiber is 2.218~2.313 μm, the elongation at break of the fiber film is up to 193%, and the dimensional stability and wettability of the fiber film are maintained at 37°C. The degradation cycle is 2~3 months.

PP/FG composite materials were prepared by compressing moulding under high temperature through high-speed mixer, mixing mill and vulcanization machine taking PP as the matrix resin, FG as the thermal conductive filler, and NDZ-201 as the coupling agent. Effects of PP proportion, FG content and particle size on the thermal conductivity and mechanical properties of composite materials were studied. Results showed that PP proportion has little effect on the thermal conductivity of PP/FG composite materials, but it greatly affects the mechanical properties of the composite materials. Overall, the quality ratio of PP230 to K-4038 at 50:50 is more suitable. With the increasing of FG content, the thermal conductivity increases, and a significant critical value appears when the FG content is 50 wt%; The strength of the composite material first decreases and then increases, with an increase in modulus and a decrease in strain. As the FG particle size increases, the thermal conductivity of the composite material increases and the mechanical properties decrease.

This study describes a polymer potentially used as a vaccine adjuvant. We first synthesized a novel polyacrylic acid modified by perfluorinated butanol—a bioactive compound that is biocompatible. The main aim was to functionalize the polyacrylic acid by fluorine. This functionalization could offer a permanent graft by an esterification reaction. The chemical structure of the polymer has been characterized by the hydrogen nuclear magnetic resonance spectrum (1H-NMR) and fourier transform infrared spectrum (FT-IR). Thermal analysis showed that the esterification reaction was successful on the polyacrylic acid. Viscosity testing showed that the viscosity of the sample aqueous solution increases along with esterification. The surface tension of the polymer was also tested. The results show that the surface tension of the polyacrylic acid markedly decreased when modified by fluorine. Finally, the interaction of these materials with macrophages was tested on cell test. Results showed that the modified polyacrylic acid performed better improve the activation effect than pure polyacrylic acid in 1L-1β.

Poly (DL-lactide)/Poly (ethylene glycol) diblock copolymer is successfully synthesized with mPEG and DL-LA as main raw materials, and the residual monomers of the polymer were removed by recrystallization. FT-IR is used to characterize the structure of the polymer. Gas chromatography is used to determine the residual monomers and residual solvent of the polymer. The solubility of polymer in different solvents was determined, and the effect of different solvent systems on the removal of residual monomers in copolymer were discussed. The results showed that the Poly(DL-lactide)/Poly(ethylene glycol) diblock copolymer was recrystallized with acetone/ isopropyl ether solvent system has the best ability to remove residual monomers, and the residual monomers of the obtained polymer are less than 0.01 wt%, the total residual solvent is only 0.24 wt%, and the productivity is as high as 95.5 wt%.