Guoquan Zhu

Structure and Performance of Poly(vinyl alcohol)/Poly(γ-benzyl L-glutamate) Blend Membranes

Poly(vinyl alcohol) (PVA)/poly(γ-benzyl L-glutamate) (PBLG) blend membranes with different PBLG wt contents were prepared by pervaporation. Structure and surface morphologies of PVA/PBLG blend membranes were investigated by Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). Thermal, mechanical, and chemical properties of PVA/PBLG blend membrane were studied by differential scanning calorimeter (DSC), tensile strength tests, and other physical methods. It was revealed that the introduction of PBLG homopolymer into PVA could exert an outstanding effect on the properties of PVA membrane.

Properties Study of Poly(L-lactic acid)/Polyurethane-Blend Film

Poly(L-lactic acid) (PLLA)/polyurethane (PU)-blend films were prepared by casting the polymer blend solution in chloroform. Surface morphologies of the PLLA/PU-blend films were investigated by scanning electron microscopy (SEM). Thermal, mechanical, and chemical properties of PLLA/PU-blend films were studied by differential scanning calorimetry (DSC), tensile tests, and contact angle testing. It was indicated that the addition of PU could exert marked effects on the properties of PLLA films.

Properties of Polypeptide-Based Membrane Improved by Flexible Poly(ethylene glycol)

Poly(γ-benzyl L-glutamate)/poly(ethylene glycol) (PBLG/PEG) polymer blend membranes were prepared by casting the polymer blend solution in chloroform. Surface morphologies of the polymer blend membranes were investigated by atomic force microscopy (AFM) and scanning electron microscopy (SEM). Thermal and mechanical properties of the polymer blend membranes were researched using differential scanning calorimeter (DSC) and tensile tests. It was revealed that the introduction of PEG could exert outstanding effects on the morphology and the properties of the polymer blend membranes.

Properties of polyurethane-poly(2,2,3,3-tetrafluoropropyl acrylate) triblock copolymer aqueous dispersion and its film cast from the dispersion

Polyurethane-poly(2,2,3,3-tetrafluoropropyl acrylate) (PU-PTFPA) triblock copolymer aqueous dispersions were synthesized by three-step polymerization. Infra-red (IR) data verify the copolymerization between PU and TFPA. The properties of copolymer aqueous dispersion and its film cast from the dispersion have been investigated by transmission electron microscopy (TEM), dynamic light scattering (DLS), and some other physical testing methods. TEM observations indicate that the morphologies of copolymer particles formed in water are almost irregular spherical shape with core-shell structure. DLS results verify that the introduction of TFPA monomer changes the average particle size of copolymer particles. The experimental data demonstrate that the factors influencing the properties of PU-PTFPA triblock copolymer aqueous dispersion and its film cast from the dispersion mainly involve PU content, DMPA content and PTFPA content.

Thermal, Mechanical and Chemical Properties of Hydrophilic Poly(vinyl alcohol) Film Improved by Hydrophobic Poly(propylene glycol)

A series of poly(vinyl alcohol)/poly(propylene glycol) (PVA/PPG) blend films with different PPG contents were prepared by casting the polymer blend solutions. Structure and morphologies of the PVA/PPG blend films were studied by Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). Thermal, mechanical, and chemical properties of PVA/PPG blend films were investigated by differential scanning calorimeter (DSC), thermogravimetric analysis (TGA), tensile strength tests, and other physical methods. It was revealed that the introduction of PPG could exert marked effects on the morphology and the properties of PVA film.

Poly(vinyl alcohol) Membrane Modified by Polyurethane

A series of poly(vinyl alcohol) (PVA)/polyurethane (PU) blend membranes were prepared by casting the polymer blend solution in dimethyl sulfoxide (DMSO). Structure and morphologies of PVA/PU blend membranes were investigated by atomic force microscopy (AFM) and scanning electron microscopy (SEM). Thermal, mechanical, and chemical properties of PVA/PU blend membrane were studied by differential scanning calorimetry (DSC), tensile tests, and surface contact angle tests. It was found that the introduction of PU could exert marked effects on the morphology and the properties of PVA membrane.

Morphology and properties of hydrophobic polypeptide-based film improved by hydrophilic poly(vinyl alcohol)

Poly(γ-benzyl l-glutamate)/poly(vinyl alcohol) (PVA) blend films were prepared by a solution casting method. Surface morphologies of the polymer blend films were investigated by atomic force microscopy and scanning electron microscopy. Thermal, mechanical, and physical properties of the polymer blend films were studied by differential scanning calorimetry, tensile tests, and contact angle tests. It was revealed that the introduction of PVA could exert pronounced effects on the morphologies and the properties of the polypeptide films.

Properties of poly(γ-benzyl L-glutamate) membrane modified by polyurethane containing carboxyl group

A series of poly(γ-benzyl l-glutamate) (PBLG)/polyurethane (PU) containing carboxyl group blend membranes was prepared by casting the polymer blend solution in dimethylformamide (DMF). The surface morphology of the PBLG/PU blend membranes was investigated by atomic force microscopy (AFM) and scanning electron microscopy (SEM). Thermal, mechanical, and chemical properties of PBLG/PU blend membranes were studied by differential scanning calorimetry (DSC), tensile tests and other physical methods. It was revealed that the introduction of PU could exert outstanding effects on the morphology and the properties of PBLG membrane.

Surface Morphology and Properties of Rigid Poly(γ-benzyl L-glutamate) Membrane Modified by Flexible Poly(Vinyl Chloride)

Rigid poly(γ-benzyl L-glutamate)/flexible poly(vinyl chloride) (PBLG/PVC) blend membranes were prepared by casting the polymer blend solution in dichloroethane. Structure and morphologies of the PBLG/PVC blend membranes were investigated by Fourier transform infrared spectroscopy (FT-IR), atomic force microscopy (AFM), and scanning electron microscopy (SEM). Thermal, mechanical, and chemical properties of PBLG/PVC blend membranes were studied by differential scanning calorimetry (DSC), tensile tests, and other physical methods. It was found that the introduction of PVC could exert marked effects on the morphology and the properties of PBLG membrane.

Reaction Factors Influencing the Synthesis of Polystyrene-Polyurethane-Polystyrene Triblock Copolymer

Polystyrene-polyurethane-polystyrene (PS-PU-PS) triblock copolymer was synthesized by two-step polymerization. The first step, polyurethane (PU) prepolymers based on 2,4-toluene diisocyanate (TDI), hydrophilic poly(ethylene glycol) (PEG), hydroxyethyl acrylate (HEA), and ethylene glycol (EG), were prepared with ethylene glycol as a chain extender, dibutyltin dilaurate as a catalyst, and toluene as a solvent. The next step, polystyrene-polyurethane-polystyrene (PS-PU-PS) triblock copolymers, were prepared by free radical copolymerization between PU prepolymer and styrene (ST) monomer. Toluene and 2,2′-azobisisobutyronitrile (AIBN) were used as solvent and initiator, respectively. Fourier transform infrared spectroscopy (FT-IR) spectroscopy was used to characterize the structure of the copolymer. Influences of reaction temperature, reaction time, catalyst sorts, isocyanate monomer sorts, solvent sorts, and the concentration of initiator on the synthesis of the triblock copolymer were studied.