Facile Preparation of Concentration-Gradient Materials with Radical Spin of the Mixed-Valence Tetrathiafulvalene in Conventional Polymer Films

Abstract

We describe here the facile methods for the stepwise regulation of the formation of tetrathiafulvalene (TTF) radical cation and the self-assembly to the mixed-valence state of TTF in various polymer films. The homogeneous polymer composites containing TTF and (1R)-3,3-dimethylbicyclo[2.2.1]hepta-2-one-1-triflate as a photoinduced acid generator in several kinds of conventional polymers were prepared, and the phototriggered conversion of TTF to radical cation via protonation in the films was executed. The amount of the TTF radical species can be controlled by the length of UV-irradiation time to the polymer composite films. In addition, the formation of the mixed-valence TTF can be observed in the composite films by annealing after UV irradiation when the glass transition temperature of the matrices was sufficiently higher than the reaction temperature during the photoirradiation. Finally, we presented the facile patterning method for preparing the composite with the concentration gradient of TTF radical and the mixed-valence TTF.

Gradient polymer networks formed by photopolymerization with self‐floating polysiloxane‐containing nanogel

“…M‐Si‐L/M/H, UDMA and IBMA at a molar ratio of 10:20:70 were used to synthesize polysiloxane‐containing nanogels. Synthesis details and operation methods are similar to previous publication . The difference is that the resulting clear nanogel reaction mixture was added drop‐wise to an eight‐fold excess of hexanes (for Si10L) or methanol (for Si10M and Si10H) to precipitate the polymeric materials.…”

“…Synthesis details and operation methods are similar to previous publication. [26] The difference is that the resulting clear nanogel reaction mixture was added drop-wise to an eight-fold excess of hexanes (for Si10L) or methanol (for Si10M and Si10H) to precipitate the polymeric materials. The final polysiloxane-containing nanogels are designated as Si10L, Si10M and Si10H, respectively, to represent the 10 mol% component and different chain lengths of the polysiloxane in the nanogels.…”

“…Subsequently, Yang et al have just utilized the self‐shield effect of UV‐light to generate a gradient of radical concentration along the vertical direction in photopolymerization systems, thereby preparing PGMs with molecular weight gradient. We have proposed a fast, convenient and environmentally friendly method for preparing molecular weight gradient polymer by using a polysiloxane benzophenone photoinitiator with self‐floating capability, which leads to the spontaneous formation of a concentration gradient of the photoinitiator in photopolymerization system . However, this method is hugely restricted in preparing gradient polymers with high performances that are related to the structure, composition and molecular weight of the polymer, because the properties of the prepared gradient polymer using the polysiloxane benzophenone photoinitiator only can be regulated by the polymer molecular weight, which relates to the photoinitiator closely.…”

“…We have proposed a fast, convenient and environmentally friendly method for preparing molecular weight gradient polymer by using a polysiloxane benzophenone photoinitiator with self-floating capability, which leads to the spontaneous formation of a concentration gradient of the photoinitiator in photopolymerization system. [26][27][28] However, this method is hugely restricted in preparing gradient polymers with high performances that are related to the structure, composition and molecular weight of the polymer, because the properties of the prepared gradient polymer using the polysiloxane benzophenone photoinitiator only can be regulated by the polymer molecular weight, which relates to the photoinitiator closely. In view of this, we propose a new idea that the polysiloxane is introduced into nanogels to obtain polysiloxane-containing nanogels for preparing gradient polymers.…”

Physical and electrical characteristics of supramolecular polymer films based on guanosine derivatives modified with tetrathiafulvalene moiety

“…This was attributed to the presence of the large TTF terminal unit. 27 In repeated DSC heating runs, the T m s of the derivatives shifted to lower temperatures. As the 1 H NMR spectra showed no apparent decomposition of the derivatives after DSC analysis, the shifts of T m were probably caused by changes in intermolecular interactions in the film state via thermal treatments.…”