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The observation of the inner structure of materials without pretreatment or damage is a very useful analytical method in the field of materials science as well as in medicine and biology. We have carried out a three-dimensional (3D) analysis of biodegradable polyester bacterial-poly[(R)-3-hydroxybutyrate-co-(R)-3-hydroxyvalerate] (P(3HB-co-3HV)) fibers with high tensile strength (1.07GPa) using X-ray...
This feature article describes the application of nitroxide-mediated controlled/living free-radical polymerization in aqueous dispersed systems such as miniemulsion and emulsion polymerizations. It mainly focuses on the acyclic nitroxide SG1 with derived alkoxyamines and aims to show how the recent development of new water-soluble species has allowed a true emulsion polymerization process to be successfully...
A simulation model based on self-consistent mean field theory (SCMFT) has been developed to inspect the approaching process of the polymer chain grafted AFM tip to a substrate. The effects of various controlling parameters, such as grafting position, chain number, chain length, as well as solvent- and substrate-chain interactions, on the force curve were investigated. Real force spectroscopy of AFM...
A simple and efficient method is presented for the preparation of polymer-grafted TiO 2 by a photocatalytic polymerization. PMMA chains are directly grafted from the surface of the TiO 2 nanoparticles in water under sunlight illumination. FT-IR and TEM results demonstrate that there existed strong chemical bonding at the interface of TiO 2 nanoparticles and PMMA chains. The...
This report deals with the study of the plastic deformation processes of semi-crystalline polymers at the micrometric and nanometric scales by atomic force microscopy. Capturing images from the same locus of the sample as a function of strain allows in situ observation of the processes. New experimental findings regarding initiation, growth and coalescence of crazes in poly(1-butene) are reported...
A series of novel mesogen-jacketed polymers, poly{2,5-bis[(5-tert-butylphenyl)-1,3,4-oxadiazole]styrene} (P-Ct) and poly{2,5-bis[(5-alkoxyl-phenyl)-1,3,4-oxadiazole]styrene} (P-OCn, n is the number of carbons in the alkoxyl groups, n=6, 8, 10, 12, 14), were incorporated into polymer light-emitting device as the light-emitting layers. All of the polymers had excellent solubility in common organic solvents...
A hindered phenol (AO-80) was studied to prepare rubber nanocomposites with nitrile butadiene rubber (NBR). The NBR/AO-80 rubber nanocomposites were successfully developed by applying the adopted preparation procedure/conditions, especially by introducing mechanical kneading of the NBR/AO-80 composites at a temperature higher than the melting point of AO-80, followed by the crosslinking of NBR molecules...
The thiol group-terminated polythiophenes were prepared via the Pd-catalyzed coupling reaction of the bromo group-terminated polythiophene derivatives and methylthiophenylboronic acid, and were mixed with the nanometer-sized gold particle to form a self-assembled network film of the alternate conjugation of the polythiophene with the gold nanoparticle. The electron microscopy and X-ray photoelectron...
Quantum mechanical calculations at the density functional theory level have been used to examine the interaction between 3,4-ethylenedioxythiophene and N-methylpyrrole units when they are directly linked in copolymer chains. Specifically, in this study, which was motivated by experimental observations of electrochemically synthesized copolymers, the conformation and electronic properties of co-oligomers...
The structure–property relationships of thermoplastic olefin (TPO)-based nanocomposites prepared by melt processing are reported with a main focus on the ratio of maleic anhydride-grafted polypropylene (PP-g-MA) to organoclay. The morphological observations by transmission electron microscopy, atomic force microscopy, and X-ray diffraction are presented in conjunction with the mechanical and rheological...
Novel one-step preparation of polymer electrolyte membranes without a membrane casting process is achieved by radiation crosslinking of a polyetheretherketone (PEEK) film to prevent dissolution and deformation of the original film in sulfonating solutions. The films crosslinked with doses more than 33MGy can be effectively sulfonated in a chlorosulfonic solution, resulting in a crosslinked sulfonated...
The thermal properties and the isothermal hot crystallization behavior of a new regular polyester constituted of glycolic acid and 6-hydroxyhexanoic acid units were studied by differential scanning calorimetry (DSC). The morphological development during isothermal crystallization was also investigated using simultaneous small-angle X-ray scattering (SAXS) and wide-angle X-ray diffraction (WAXD) techniques...
Taking advantage of the simultaneous polymerization and self-assembly between the components during the template polymerization, narrowly distributed nanoparticles with core-shell structure were prepared at high concentrations via polymerizing acrylic acid (AA) in aqueous solution of template gelatin. The influences of various polymerization parameters such as medium pH, concentration, and ratio of...
Poly(butyl methacrylate) (PBMA) latex particles have been copolymerized with new fluorescent naphthalimide dyes by miniemulsion polymerization. A new pair of naphthalimide dye monomers was synthesized and copolymerized with butyl methacrylate (BMA) via miniemulsion polymerization, producing approximately 80nm diameter particles with a narrow size distribution. We were able to prepare polymers with...
The light sensitive vinyl monomer with coumarin unit, 7-(4-(acryloyloxy)butoxy)coumarin (7AC), was synthesized. The reversible addition–fragmentation chain transfer (RAFT) polymerization of 7AC, initiated by 2,2′-azobisisobutyronitrile (AIBN), was carried out using 2-cyanoprop-2-yl dithiobenzoate (CPDB) as a RAFT agent in N,N-dimethylformamide (DMF) solution. The kinetics exhibited first-order relationship...
A series of polypropylene/poly(ethylene-co-propylene) (PP/EPR) in-reactor alloys were synthesized by the homopolymerization of propylene in the first stage, after that it switches to gas-phase ethylene–propylene copolymerization and gas-phase homopolymerization of propylene in a circular mode. The alloys were characterized by FTIR, DSC, PLM, TEM and SEM. Changing switch frequency had hardly any influence...
Monodisperse silica/polydivinylbenzene (SiO 2 /PDVB) and silica/poly(ethyleneglycol dimethacrylate) (SiO 2 /PEGDMA) core–shell hybrid microspheres were prepared by a two-stage reaction with silica particles' grafting of 3-(methacryloxy)propyltrimethoxysilane (MPS) as core and PDVB or PEGDMA as shell, in which the MPS-modified silica core with diameter of 238nm was synthesized by Stöber...
The morphology and corresponding performance of holographic polymer dispersed liquid crystals (HPDLCs) based on thiol–ene polymer are dependent on a number of factors including the gel point conversion of the polymer, polymerization kinetics, and extent of liquid crystal (LC) phase separation. Previous research of HPDLC reflection gratings made from thiol–allyl ether polymer indicates that increasing...
This work deals with ring-opening polymerization of a representative N-carboxy-α-amino acid anhydride (NCA) in ionic liquids. The polymerization of γ-benzyl-l-glutamate-N-carboxyanhydride (BLG-NCA) with n-butylamine as an initiator in an ionic liquid ([BMI][PF 6 ]) proceeded as a milky white dispersion with no evidence of macroscopic precipitation. The polymerization with the primary amine...
We characterize the DC conductivity (σ 0 ) of solution electrolytes prepared by adding LiCF 3 SO 3 (LiTf) salt to a (50/50 w/w) solution of branched poly(ethyleneimine) (PEI) in N,N-dimethylformamide (DMF). The value of σ 0 increases with decreasing LiTf concentration over the range of compositions studied due to the formation of contact ion pairs at higher LiTf concentrations,...
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