Xiaozhen Tang

A novel polymer electrolyte based on polydioxolane polyurethane with Na+ single-ionic conductivity

A series of novel polyurethane ionomers with polydioxolane (PDXL) as soft segment was prepared and characterized by Fourier transform infrared spectroscopy, differential scanning calorimetry, and dynamic mechanical analysis. The ionomers obtained were Na+ single-ionic conductors. Their ionic conductivity and water absorption were tested. At medium temperature (> 75°C), the conductivity of ∼ 10−5 s cm−1 was reached. The temperature dependence of conductivity could not be well expressed by both Arrhenius and VTF equations. When ionization level was fixed, the conductivity increased as the Mn of PDXL decreased. We also discussed the effect of ionization level on water absorption.

Porous polyurethane/acrylate polymer electrolytes prepared by emulsion polymerization

Abstract Using a new method: emulsion polymerization, a novel polyurethane/acrylate (PUA) porous polymer was prepared. Compared with traditional phase inversion method, the new method can eliminate the pollution produced in process of plasticizer extraction and decrease the cost of production. The porous polymers were immerged in 1 mol kg −1 solution of LiClO 4 /PC to form polymer electrolytes. The structures of porous polymers and porous polymer electrolytes were observed with SEM. The conductivity of the polymer electrolytes was found to be as high as 10 −3 S cm −1 which could be useful in many practical electrochemical devices. At the same time, the conductive mechanism of porous gel electrolytes with different liquid content was discussed.

Morphology and ionic conductivity of solid polymer electrolytes based on polyurethanes with various topological structures

Polyurethanes with linear, hyperbranched and comb-crosslinked structures were synthesized and were used to prepare solid polymer electrolytes. The polymer electrolytes were characterized by means of Fourier transform Raman spectroscopy, impedance spectroscopy (IS) and atomic force microscopy (AFM). The results showed that salt concentration significantly influences the morphology and conductivity of the three kinds of polyurethane/LiClO4 system. When the mole ratios of the ether oxygen atom to lithium ion were controlled to be 12, 4 and 4 respectively for linear, hyperbranched and comb cross-linking polyurethane, the electrolytes typically displayed micro-phase separated morphology and the ionic conductivity also reached maxima respectively at 2.2 × 10−7 S/cm, 2.8 × 10−6 S/cm and 2.8 × 10−5 S/cm at room temperature.

The effects of salt concentration on ion state and conductivity in comb cross-linked polymer electrolytes

A new type of comb cross-linked polyurethane/acrylate polymer was designed. The polymer has sparse network structure with many long comb molecule chains. A new solid polymer electrolyte (SPE) was prepared based on the polymer. The salt in the solid polymer electrolytes has different existent states with different salt contents. With increase of salt concentration, the ion pairing gradually becomes important existent form of salt, and Tg value of the SPE increases. At the same time, ionic conductivity increases rapidly. It is possible to design novel solid polymer electrolytes with high ionic conductivity to meet practical application by comb cross-linked polymer with high salt content.

A novel gel polymer electrolyte based on the comb crosslinking polymer

A new type of polymer, comb crosslinking polymer, was designed. The polymer has sparse network structure with many long comb molecule chains. A new flexible, transparent, gel polymer electrolyte (GPE) was prepared on the base of the polymer. The polymer electrolyte showed good conductivity and should have good mechanical properties. When plasticizer was only 50 wt.%, the GPE could reach a high ionic conductivity.

Study on ionic conductive property of polyurethane/oligo-ether sulfate complex

Abstract A new oligo-ether sulfate (SPEG) and linear polyether urethane (PU) have been synthesized successfully, and a series of novel solid polymer electrolytes based on PU/oligo-ether sulfate complexes were prepared. Effects of temperature, salt concentration (O:Na+, the molar ratio of ether unit to sodium cation), content of SPEG and polydioxolane (PDXL) on morphological structure and ionic conductive property were investigated in detail. It was found that oligo-ether sulfate had great effect on morphological structure of samples. Results showed that ionic conductivity of this system could reach 10−5xa0S cm−1 at medium temperature (60°C) and temperature dependence of ionic conductivity was not an Arrhenius-type one. The ionic conductivity increased with increase of SPEG content over whole range of salt concentration studied and ionic conductivity of SPU-600 was higher than that of SPU-400 at the same O:Na+. In addition, plasticizer PDXL and its content significantly influenced the ionic conductive properties of the samples.

The study of a thermoplastic polyurethane ionomer system

Abstract A novel ionomer system of a thermoplastic polyurethane (TPU) and poly(styrene–acrylic acid) (PSAA) was designed and prepared successfully. The compatibility of the system was greatly improved due to ionic bonding formed through tertiary amine and carboxylic acid groups. The structure and properties of the ionomer materials were characterized by means of DMA, SEM, swelling ratio and viscosity measurements, and a compatible TPU/PSAA ionomer system was observed at a PSAA content of 60%.

Synthesis and characterization of polydioxolane polyurethane ionomer

A series of novel sodium salts of sulfonated polyurethane ionomers with polydioxolane as soft segment was successfully synthesized and their properties were characterized by means of Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and complex impedance analysis. As the ionization level increased, the compatibility of the hard segments and soft segments was improved and the glass transition region of soft segment became broader. The effects of ionization level, temperature, chemical components of soft segment on ionic conductivity of ionomers were investigated in detail. Adjusting the ionization level and incorporating PEG soft segment into the PDXL-PU ionomers, a new type of solid polymer electrolyte material with good mechanical properties and high ionic conductivity could be obtained.