21217-75-4Relevant articles and documents
Phosphate cross-linking agent and preparation method thereof, phosphate-based cross-linked gel polymer electrolyte and preparation method and application thereof
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Paragraph 0047-0048; 0057, (2020/08/17)
According to the invention, the safety of the battery can be improved based on introduction of phosphate into the gel polymer electrolyte, , the adjustable flexibility is improved by introduction of aPEO chain segment, and the stability and the polymerization capability are improved by introduction of acrylate; thus, further research is carried out on the basis of the prior art, the polyfunctional phosphate cross-linking agent is obtained and is applied to the preparation of the phosphate-based cross-linked gel polymer electrolyte, so the cross linking agent can be copolymerized with other functional monomers to synthesize gel polymer electrolyte; the gel polymer electrolyte has the advantages of simple and convenient preparation method, high ionic conductivity, high thermal stability andgood electrochemical stability, the assembled sodium ion battery has good cycling stability and high-temperature performance, and the phosphate-based gel polymer electrolyte with high safety is provided for quasi-solid sodium/lithium ion batteries.
Polymerized ionic liquids with enhanced static dielectric constants
Choi, U Hyeok,Mittal, Anuj,Price, Terry L.,Gibson, Harry W.,Runt, James,Colby, Ralph H.
, p. 1175 - 1186 (2013/04/10)
Dielectric spectroscopy was used to determine the static dielectric constants (εs) of imidazolium acrylates and methacrylates and their ionomers, with different imidazolium pendant structures containing a combination of alkylene [(CH2)n, n = 5 or 10] and ethyleneoxy [(CH2CH2O)n, n = 4 or 7.3 (the average of a mixture of n = 1 to 20)] units as spacers between the backbone and the imidazolium cation. All monomers and polymers exhibited two dipolar relaxations, assigned to the usual segmental motion (α) associated with the glass transition and a lower frequency relaxation (α2), attributed to ions rearranging. From the analysis of the static dielectric constants using the Kirkwood g correlation factor, the dipoles in conventional (smaller) ionic liquids prefer antiparallel alignment (g ≈ 0.1), lowering εs values (≤30), because their polarizability volumes V p strongly overlap, whereas the dipoles in the larger ionic liquid monomers display g of order unity and 50 ≤ εs ≤ 110. A longer spacer leads to higher static dielectric constant, owing to a significant increase of the relaxation strength of the α2 process, which is directly reflected through an unanticipated increase of the static dielectric constant with ionic liquid molecular volume Vm. The glass transition temperature of polymerized imidazolium ionic liquids with various counterions is also shown to simply be a monotonically decreasing function of Vm. Furthermore, the ionomers consistently exhibit 1.5-2.3 times higher static dielectric constants (εs up to ～140 at room temperature) than the monomers from which they were synthesized, suggesting that polymerization encourages the observed synergistic dipole alignment (g > 1).
Adhesive composition
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, (2008/06/13)
An adhesive composition comprises 100 parts by weight of a polymerizable monomer comprising (a) 1.5 to 100 parts by weight of a compound represented by general formula I or II: STR1 where R1 and R1 ' each stand for hydrogen or a methyl group, R2 stands for a divalent organic residue having 4 to 40 carbon atoms, X1 and X2 each stand for --O--, --S-- or --NH--, a is 0 or 1, and R3 stands for a group of the formula STR2 having 6 to 40 carbon atoms, where R4 and R4 ' each stand for a hydrocarbon group having 1 to 29 carbon atoms, and optionally replaced by a halogen atom, or a hydroxyl, amino or carboxyl group, b is an integer of 0 to 3, and Z stands for --O--, --COO-- or --NH--, a plurality of R4 ' (when b is 2 or 3) being the same or different, at least one of R4 and R4 ' having at least three carbon atoms, and (b) 0 to 98.5 parts by weight of a vinyl monomer copolymerizable with the above compound; and 0.01 to 20 parts by weight of a curing agent. It shows a superior adhesive strength on any of hard tissues in a living body, such as teeth and bones, metals, organic polymers and ceramics. It maintains a high adhesive strength for a long time even if it is exposed to moisture, or immersed in water. It is particularly effective for use in dentistry, though it is useful for a variety of other purposes, too.
