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Maleimide copolymers are high-performance transparent polymer materials with excellent thermal, optical, and mechanical properties. In this comprehensive paper, we describe the control of the sequence structures for such polymers. We investigated the 1:1 alternating and 2:1 sequence-controlled copolymerizations of A-substituted maleimides with various styrene and olefin derivatives. The monomer reactivity ratios were calculated based on the analysis of the comonomer-copolymer composition curves using terminal and penultimate unit models. The 2:1 sequence-controlled (AAB-type) copolymers were produced under the penultimate unit control. The sensitivity of the penultimate unit effect depends on the structures of the comonomers and the solvents used for the copolymerization. Maleimide copolymers with excellent thermal, optical, and mechanical properties were fabricated by alternating and 2:1 sequence-controlled radical copolymerizations and subsequent postpolymerization reactions including thiol-ene reactions. An organic-inorganic hybrid was also synthesized by the thiol-ene reaction of the copolymer with silica nanoparticles and the thermal and optical properties of the obtained hybrids were investigated. [ABSTRACT FROM AUTHOR]

Direct polycondensation of renewable monomers, itaconic acid and isosorbide, was examined by using various catalysts and radical scavengers. Among the tested compounds, a combination of HfC14.2THF as a catalyst and galvinoxyl free radical as a radical scavenger was found to yield soluble polymers with relatively high molecular weights without significant isomerization of itaconic acid. The resulting polymers were amorphous, showing a Tg of ~84°C depending on their molecular weights. Treatment of the polymers with benzoyl peroxide gave an insoluble crosslinked polymer. Thus, the polycondensation of itaconic acid and isosorbide could produce sustainable and functional polymers. [ABSTRACT FROM AUTHOR]

We report on PVDF-based polymeric solid electrolytes (PSE) for dye-sensitized solar cells (DSCs). The dependence of the short-circuit current density (Jsc) on the diffusion coefficient was discussed on the basis of the equivalent circuit analysis of photocurrent in DSC. When the back electron transfer from TiO2 to an oxidized dye was taken into account, the diffusion coefficient dependence of Jsc was well explained. We confirmed that the Jsc of a PSE-based DSC with a 20 μm cell gap amounts to about 97% of that of a liquid-based DSC. We then focused on the cross-linking reaction of PVDF-HFP with amines. This cross-linking reaction allows us to carry out the otherwise inhibited in-situ reaction of the precursor inside a cell. We also studied DSCs fabricated with the cross-linked PVDF-HFP-based PSE. The energy conversion efficiency of the DSC was 4.8% with AM-1.5 illumination. [ABSTRACT FROM AUTHOR]