• Bulletin of the Korean Chemical Society
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• v.3 no.3
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• pp.115-119
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• 1982

The photoreaction of maleimide, one of the best model compounds of DNA molecules for psoralen-DNA photoreactions, is studied in order to investigate the photoreactivity and the mechanism of the maleimide-psoralen photoreaction. The (2+2) photocyclodimer of maleimide was obtained in solution state by direct or sensitized irradiation. The rate constant of dimerization is determined by quenching studies and found to be of the order of $10^9 M^{-1}sec^{-1}$. The direct dimerization of maleimide is found to undergo through the triplet excited state. The quantum yields of dimerization are dependent on the maleimide concentration.

• Bulletin of the Korean Chemical Society
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• v.27 no.10
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• pp.1542-1548
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• 2006

Maleimide modified epoxy compounds were prepared by reacting N-(4-hydroxyphenyl) maleimide (HPM) with diglycidylether of bisphenol-A. Triphenylphosphine was used as catalyst and methylethylketone as solvent. The resulting compound possessed both the oxirane ring and maleimide group. The curing reaction of the maleimide epoxy compound with amine curing agents such as 1-(2-aminoethyl) piperazine (AEP) and 5-amino-1,3,3-trimethylcyclohexane methylamine isophorone diamine, IPDA) were studied. Incorporation of maleimide groups in the epoxy resin provides cyclic imide structure and high cross-linking density to the cured resins. The cured samples were found to have good thermal stability, chemical resistance (acid/alkali/solvent) and water absorption resistance.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.3
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• pp.264-268
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• 2002

Three types of polymer, a photoalignment material based N- (phenol)maleimide were synthesized and the liquid crystal (LC) aligning capabilities on the photopolymer layer were studied. A good LC alignment with UV exposure on the PMI5CA(N-(phenol)maleimide with 5-carbon chain cinnamoyl group) can be obtained. However, the LC alignment defects were observed on the PM13CA (N-(phenol)maleimide with 3-carbon chain cinnamoyl group) and PMIF (N-(phenyl)maleimide including fluoro cinnamoyl group). Also, the good LC alignment with UV exposure on the PM15CA surface was observed at until $150^{\circ}C$ of annealing temperature. The LC aligning ability on the photopolymer layer based N-(phenol)maleimide depends on the side chain length of photopolymer.

• Bulletin of the Korean Chemical Society
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• v.3 no.4
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• pp.153-157
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• 1982

$C_4$-Photocycloaddition of 8-methoxypsoralen (8-MOP) and 5,7-dimethoxycoumarin (DMC) to maleimide was studied in order to elucidate the mechanism of the photobiological activities of these molecules. The photoreaction was carried out in chloroform solution and frozen aqueous solution state. The major product was isolated and characterized by spectroscopic methods. The photoadduct between 8-MOP and maleimide was shown to be an 1:1 $C_4$-cycloadduct through the photocycloaddition of 4',5'-furyl double bond of 8-MOP to maleimide. The stereochemistry of cyclobutane ring of this photoadduct is consistent with the anti configuration. The photoadduct between DMC and maleimide was shown to be an 1:1 $C_4$-cycloadduct through the photocycloaddition of 3,4-pyrone double bond of DMC to maleimide.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.10 no.1
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• pp.55-62
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• 2004

Synthesis of poly[N-(formyloxyphenyl)maleimide](PFOMI) as photopolymer were investigated with various kinds of photosensitive groups. Generally, photopolyimide have some deficiencies in solubility, sensitivity, reserve stability of the photosensitive solution, and the precision of image pattern. The study has been required on those polymers which have high glass transition temperature and photo efficiency, and low dielectricity. The existing condensation resins require high curing temperature and perfect elimination of subreacted materials that are produced during the process after irradiation and various membrane damages such as the deformation and contraction in image pattern cure. In this study poly[N-(hydroxyphenyl)maleimide](PHPMI) was synthesized. The PHPMI were analyzed by H-NMR and FT-IR. The measured number average molecular weight of PHPMI was produced was $1.06{\times}10^4$. Poly[N-(formyloxyphenyl)maleimide](PFOMI) as a type of photo-Fries rearrangement was synthesized by NHPMI and formic acid followed by radical polymerization. PFOMI was analyzed by FT-IR, and photocharacteristics was investgated by UV spectra and FT-IR before and after UV irradiation. Based on the image characteristics of PFOMI measured from optical micrographs, it was formed that the resolution of positive type PFOMI was $0.5{\mu}m$.

• Polymer(Korea)
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• v.26 no.2
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• pp.253-259
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• 2002

The objective of this study is to obtain thermally stable and low optical loss polymers for optical waveguiding materials. The crosslinkable poly (maleimide-co-methacrylate)s were synthesized using a pentafluorophenylmaleimide (an optical loss reducer), two methacrylate derivatives (refractive index controllers), and a glycidylmethacrylate (a crosslinker). These copolymers exhibited good thermal stability and could be thermally crosslinked by heat treatment. The refractive indexes of the copolymers could be precisely controlled by the variation of comonomer feed ratio, which was in the range of 1.45 ~ 1.49. These copolymers had very low birefringence of $6{ imes}10^{-4}$ ~ $1{ imes}10^{-4}$. These copolymers were crosslinked by contact printing and then developed by wet etching to obtain high quality waveguide pattern.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.10
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• pp.845-849
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• 2001

The new phto-alignment material PMI5CA, poly{N-(phenyl)maleimide-co-3-[4-(pentyloxy) cinamate]porpyl-2-hydroxy-1-methacrylate}, was synthesized and the electro-optical (EO)characteristics in the vertical-aligned(VA) liquid crystal display (LCD) photo-aligned on the photopolymer surface were studied. Excellent Voltage-transmittance(V-T) characteristics in the VA-LCD photoaligned with polarized UV exposure of oblique direction on the pohotopolymer surface for 1 min can be achieve. The transmittance of the VA-LCD photoaligned on the photopolymer surface decreased with increasing UV exposure time. We suggest that decrease of transmittance in the VA-LCD photoaligned on the photopolymer surface is attributed to the dissociation of the ester linkage in the photodimerized cinnamate structure with increasing UV exposure time.

• Applied Chemistry for Engineering
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• v.8 no.2
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• pp.147-153
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• 1997

Bismaleimides(BISMI) containing ester linkages were prepared by the chlorinated N-(p-carboxyphenyl)maleimide and N-(p-hydroxyphenyl)maleimide. The photosensitive properties of BISMI were investigated via changes of the irradiation time. Benzil dimethyl ketal was used as a photoinitiator. The effect of photoinitiator onto BISMI increase in average as increasing photoinitiator concentration and irradiation time. The yield of residual film and image pattern and resolution also measured and discussed.

• Polymer(Korea)
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• v.38 no.1
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• pp.49-53
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• 2014

A novel monomeric UV-absorber was prepared by the reaction of 2,4-dihydroxybenzophenone with N-4-chlorocarbonylphenylmaleimide in the presence of triethylamine. This reactive maleimide was grafted onto polypropylene (PP) by the thermal melt-processing in a mini-max-moulder. IR spectroscopic method was used for the quantitative determination of the extent of grafting of monomeric maleimide. To find the optimal reaction conditions, the dependence of reaction temperature and time and the concentration of monomeric UV-absorber was investigated on the grafting yields. The photooxidative effect of the grafted PP was evaluated in the weatherometer comparing to the PP mixed with UV-absorbers using the carbonyl index of IR spectrum. The grafted PP showed an excellent anti-photooxidative effect.

• Natural Product Sciences
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• v.21 no.1
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• pp.25-29
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• 2015

In a continuation of our studies to discover bioactive secondary metabolites from marine sources, we further investigated samples from a tryptamine and phenyl-alkane producing sponge, which resulted in the isolation of four uncommon small molecules and five nucleosides. Their structures were determined to be 7,8-dihydroimidazo[1,5-c]pyrimidin-5(6H)-one (1), 5-chlorocavernicolin (2), maleimide-5-oxime (3), 3-methylmaleimide-5-oxime (4), uridine (5), 2'-deoxyuridine (6), thymidine (7), adenine (8), and adenosine (9) by spectroscopic analyses. The isolated compounds were evaluated for inhibitory activity against soluble epoxide hydrolase (sEH) as well as the Wnt/${\beta}$-catenine signaling pathway.