Reaction of glycidyl phenyl ether with imines: A model study of latent hardeners of epoxy resins in the presence of water

The hydrolyses of several imines and their reactions with glycidyl phenyl ether were examined under highly humid conditions as a model study for the development of water‐initiated hardeners for epoxy resins. Diethyl ketone‐based imines were hydrolyzed more efficiently than methyl isobutyl ketone‐based imines. The reactions of glycidyl phenyl ether with the imines depended on their hydrolysis rates and the basicity of the amines generated from them. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 971–975, 2002     

Reversible crosslinking and decrosslinking of polymers containing alcohol moiety using an acyclic bifunctional vicinal triketone

In this article, we report reversible crosslinking and decrosslinking systems of commercially available alcoholic polymers, using a bifunctional vicinal triketone (bistriketone) as a crosslinking reagent. A small amount of the bistriketone (0.2 equiv of the tricarbonyl moiety relative to the OH group of the polymer) was added to a solution of poly(2‐hydroxyethyl methacrylate) (PHEMA) in dimethyl sulfoxide (DMSO). After 4 days, the networked polymer was obtained as a yellow‐colored gel in 97% yield. Conversely, the resulting gel could be decrosslinked by treatment with MeOH for 4 days to recover the original PHEMA in 94% yield as well as the bistriketone in 54% yield. The network formation and dissociation behaviors were investigated in detail by ¹H NMR and size exclusion chromatography experiments. Similarly to PHEMA, reversible crosslinking and decrosslinking of poly(vinyl alcohol) were achieved by addition of the bistriketone and by treatment of the resulting gel with H₂O/DMSO (1/9, v/v), respectively. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 921–928     

Synthesis and property of polyoxazolidone having fluorene moiety by polyaddition of diisocyanate and diepoxide

Polyoxazolidones having fluorenyl group were synthesized by polyaddition of 9,9‐diglycidyl fluorene with various diisocyanates. The polymer from 9,9‐diglycidyl fluorene and methylenediphenyl 4,4′‐diisocyanate was afforded in high yield although polydispersity of the polymer was found relatively broad. The IR spectrum of the obtained polymer showed two absorption in carbonyl region. One of them was assigned to the expected oxazolidone, while the other at 1710 cm^?1 appeared due to a carbonyl group of the isocyanurate moieties produced by cyclotrimerization of isocyanate. It is assumed that the cyclotrimerization would cause the broad polydispersity caused by the branched structure formed by isocyanurate. The polymers obtained with three kinds of diisocyanates (methylenediphenyl 4,4'‐diisocyanate, 1,6‐hexamethylene diisocyanate, 1,4‐phenylene diisocyanate) showed high thermal stability, as their T_d10 was depended on the structure of diisocyanate. All polymers had high transparency in a visible region. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1755–1760     

Kinetic energies to analyze the experimental auger electron spectra by density functional theory calculations

In the Auger electron spectra (AES) simulations, we define theoretical modified kinetic energies of AES in the density functional theory (DFT) calculations. The modified kinetic energies correspond to two final-state holes at the ground state and at the transition-state in DFT calculations, respectively. This method is applied to simulate Auger electron spectra (AES) of 2nd periodic atom (Li, Be, B, C, N, O, F)-involving substances (LiF, beryllium, boron, graphite, GaN, SiO₂, PTFE) by deMon DFT calculations using the model molecules of the unit cell. Experimental KVV (valence band electrons can fill K-shell core holes or be emitted during KVV-type transitions) AES of the (Li, O) atoms in the substances agree considerably well with simulation of AES obtained with the maximum kinetic energies of the atoms, while, for AES of LiF, and PTFE substance, the experimental F KVV AES is almost in accordance with the spectra from the transitionstate kinetic energy calculations.     

Synthesis and properties of polymethacrylate bearing cyclic carbonate through urethane linkage

Polymethacrylates carrying cyclic carbonate through urethane linkage were prepared by radical (co)polymerizations of 2‐methacrylic acid 2‐(2‐oxo‐[1,3]dioxolan‐4‐ylmethoxycarbonylamino)ethyl ester (CUMA). Although brittleness of typical polymers bearing cyclic carbonate groups has been limited their practical applications, some copolymers from CUMA can be cast as films with good flexibility. The copolymers from CUMA and diethyleneglycol methyl ether methacrylate are miscible with lithium bis(trifluoromethanesulfone)imide. The coordination of the lithium cation to the carbonyl groups was confirmed by infrared spectrometry. © 2007 Wiley Periodicals, Inc. JPolym Sci Part A: Polym Chem 45: 5781–5789, 2007