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Poly(γ-benzyl L-glutamate)/poly(butyl acrylate-co-methyl methacrylate) (PBLG/Poly(BA-co-MMA)) blend films were prepared by casting the polymer blend solution in dichloroethane. Surface morphology of the polymer blend film was investigated by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Thermal and mechanical properties of the polymer blend film were studied using differential scanning calorimeter (DSC) and tensile tests. It was revealed that the introduction of Poly(BA-co-MMA) into PBLG could exert marked effects on the surface morphology and the properties of the PBLG film. [ABSTRACT FROM AUTHOR]

Poly(ethylene glycol)- block-poly( γ-benzyl l-glutamate)- graft-poly(ethylene glycol) (PEG- b-PBLG- g-PEG) copolymer was synthesised by the ester exchange reaction of PEG- block-PBLG copolymer with mPEG. The self-association behaviour of PEG- b-PBLG- g-PEG in mixtures of ethanol, chloroform, and trifluoroacetic acid as denaturing acid was investigated by transmission electron microscopy, nuclear magnetic resonance spectroscopy, FT-IR spectroscopy, dynamic light scattering, and viscometry. It was revealed that the increase in denaturing acid content in the mixed system not only promoted the critical micelle concentration but also changed the morphology of the polymeric micelles from elliptical to spherical. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

series of poly(vinyl alcohol) (PVA)/poly( γ-benzyl l-glutamate)- block-poly(ethylene glycol) (PBLG- b-PEG) blend membranes with different PVA/PBLG- b-PEG mole ratios were prepared by pervaporation. Structure and morphologies of PVA/PBLG- b-PEG blend membranes were investigated using Fourier transformation infrared spectroscopy (FTIR), and atomic force microscopy (AFM). Mechanical and chemical properties of PVA/PBLG- b-PEG blend membrane were studied by tensile testing and other physical methods. It was revealed that the introduction of PBLG- b-PEG copolymer has significant effect on the properties of a PVA membrane. [ABSTRACT FROM AUTHOR]

Poly( γ-benzyl l-glutamate)- graft-poly(ethylene glycol) (PBLG- graft-PEG) copolymer was synthesized by the ester exchange reaction of PBLG homopolymer with mPEG. Aggregation behavior of the PBLG- graft-PEG copolymer in mixtures of ethanol and chloroform was investigated by transmission electron microscopy (TEM), dynamic light scattering (DLS), and viscometry. Effects of the polymer solution concentration, grafting degree, test temperature, and chloroform content on the morphology, average particle diameter, and critical micelle concentration (CMC) of the micelles formed by the PBLG- graft-PEG copolymer in the mixed solvents were mainly studied. It was revealed that the PBLG- graft-PEG copolymer can self-assemble into polymeric micelles with a core-shell structure in various shapes depending on the preparation conditions. [ABSTRACT FROM AUTHOR]

Poly(ethylene glycol)- block-poly( γ-benzyl l-glutamate)- graft-poly(ethylene glycol) (PEG- block-PBLG- graft-PEG) copolymer was synthesized by the ester exchange reaction of PBLG- block-PEG copolymer with a PEG chain. Surface morphology of the PEG- block-PBLG- graft-PEG copolymer membrane was characterized by atomic force microscopy (AFM). Mechanical and chemical properties of the PEG- block-PBLG- graft-PEG copolymer membrane were investigated by tensile testing and contact angle testing. The effects of grafting ratio on the properties of PEG- block-PBLG- graft-PEG copolymer membrane were primarilly studied. [ABSTRACT FROM AUTHOR]

Poly( γ-benzyl l-glutamate)- graft-poly(ethylene glycol) (PBLG- graft-PEG) copolymer was synthesized by the ester exchange reaction of the PBLG homopolymer with PEG. NMR spectroscopy was used to confirm the composition of the PBLG- graft-PEG copolymer. FTIR spectroscopy was used to characterize the chain conformation of polypeptide segments in the PBLG- graft-PEG copolymer in solid state. The self-assembly behavior of PBLG- graft-PEG and its mixtures with PBLG in ethanol were investigated by transmission electron microscopy (TEM) and viscometry. Experimental results showed that the PBLG- graft-PEG copolymer can self-assemble to form polymeric micelles with a core-shell structure of a thin shuttle-like shape. The introduction of the PBLG homopolymer into the mixed system not only decreases the critical micelle concentration (CMC) but also changes the morphology of the micelles from their shuttle-like shape to cylindrical shape. The effects of test temperature on the critical micelle concentration of PBLG- graft-PEG were also studied. [ABSTRACT FROM AUTHOR]

Poly(ethylene glycol)-block-poly(γ-benzyl L-glutamate)-graft-poly(ethylene glycol) (PEG-b-PBLG-g-PEG) copolymer was synthesized by the ester exchange reaction of poly(γ-benzyl L-glutamate)-block-poly(ethylene glycol) (PBLG-block-PEG) copolymer with PEG chain, and PBLG-block-PEG copolymer was prepared by a standard N-carboxyl-γ-benzyl-L-glutamate anhydride (NCA) method. Nuclear magnetic resonance (NMR) spectroscopy was used to confirm the components of PBLG-block-PEG and PEG-b-PBLG-g-PEG. The self-association behaviors of PBLG-block-PEG and PEG-b-PBLG-g-PEG in ethanol were investigated by transmission electron microscopy (TEM), dynamic laser scattering (DLS), and viscometry. The experimental results revealed that the different molecular structures could exert marked effects on the self-assembly behaviors of PBLG-block-PEG and PEG-b-PBLG-g-PEG in ethanol. PBLG-block-PEG and PEG-b-PBLG-g-PEG could self-assemble to form polymeric micelles with a core-shell structure in the shapes of plump spherical and regular rice-like, respectively. Effects of the introduction of PBLG homopolymer on the average particle diameter of the micelles of PBLG-block-PEG and PEG-b-PBLG-g-PEG and influence of testing temperature on the critical micelle concentration of different copolymers were studied. [ABSTRACT FROM AUTHOR]

Poly( γ-benzyl L-glutamate)- graft-poly(ethylene glycol) (PBLG- graft-PEG) copolymer was synthesized by the ester exchange reaction of PBLG homopolymer with PEG chain. Chemical structure of PBLG- graft-PEG was confirmed by nuclear magnetic resonance (NMR) spectroscopy, morphology of copolymer membrane was investigated using scanning electron microscopy (SEM), and thermal transition behavior was studied using differential scanning calorimeter (DSC). It was revealed that PBLG- graft-PEG copolymer holds different structure and performance compared with PBLG homopolymer. The introduction of PEG chains not only decreases the melting point of PBLG segments in PBLG- graft-PEG, but also changes the morphology of PBLG segments. Influence of grafting ratio on chemical and mechanical properties of PBLG- graft-PEG copolymer membrane was studied. [ABSTRACT FROM AUTHOR]