• Bulletin of the Korean Chemical Society
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• v.23 no.7
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• pp.1031-1034
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• 2002

• Macromolecular Research
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• v.11 no.4
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• pp.236-240
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• 2003

Fabrication of a graded index profile was possible via photochemical reaction of cinnamoyl groups with 350 nm wavelength UV light to form crosslinked structures. Such structural change may induce the change in the refractive index. In order to generate graded index profile in the PMMA polymer optical fiber (POF) with cinnamoyl groups by photochemistry, a methyl methacrylate monomer containing a cinnamoyl functional group in the side chain were prepared. This monomer was then copolymerized with methyl methacrylate with various compositions not only to utilize advantages of poly(methyl methacrylate) but also to overcome the drawbacks of the cinnamate homopolymer. Changes of refractive indices were investigated with various contents of cinnamoyl group and varying irradiation time. Large change in the refractive index (${\Delta}{\approx}0.01$) and its proper profile shape ($g{\approx}2.2$) can be obtained by changing irradiation time.

• 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.

• Journal of the Korean Graphic Arts Communication Society
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• v.18 no.1
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• pp.113-120
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• 2000

A previous paper was reported in being sensetized photopolymer, poly(vinyl cinnamoyl acetate) (PVCiA)1) with some squarylium dyes such as 1,3-bis(4 or 6-trifluouomethy1-1,3,3-trimethylindo) squarylium dyes(TFSQ). Here, we synthesized new 1,3-bis(4 or 6-nitro-1,3,3-trimethylindo) squarylium dyes(NISQ) to sensetize photopolymer, such as poly(vinyl cinnamoyl acetate). Absorption's coefficient of (NISQ8) is 8.5x105, the sensitivity of PVCiA added with NISQ8(3%) was highly sensitized 8 times than not added, and 2 times than TFSQ8(3%). Maybe, high absorption'scoefficient and red shift of NISQs with strongly withdrawing group to TFSQs afford to the high sensitivity of PVCiA.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.11a
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• pp.583-585
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• 2004

In this paper, we synthesized a new photo-crosslinkable polyitaconimide containing cinnamoyl moiety by radical polymerization. Also, the NLC alignment capabilities on these photopolymer surfaces were studied. Good LC alignment with W exposure on the polyitaconimide surfaces can be obtained. A homogenous alignment using UV exposure on the polyitaconimide with 1-carbon chain cinnamoyl group and 4-carbon chain cinnamoly group can be obtained. However, the homeotripic alignment using UV exposure was observed on polyitaconimide with 6-carbon chain cinnamoyl. The LC aligning ability on the polyitaconimide depends on the side chain length of photopolymer.

• Korean Chemical Engineering Research
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• v.56 no.2
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• pp.143-150
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• 2018

Oil-in-water emulsion was prepared using cinnamoyl surfactants as emulsifiers. Cinnamoyl surfactants used in the present study were polyoxyethylene (20) sorbitan monolaurate-cinnamic acid conjugate (TW20CA), polyoxyethylene (20) cetyl ether-cinnamic acid conjugate (CE20CA), and polyoxyethylene(20) oleyl ether-cinnamic acid conjugate (OE20CA). The emulsion stabilized with TW20CA was the most stable, possibly because the polyoxyethylene segment of TW20CA would sterically stabilize the oil droplets effectively. In vivo UV protecting efficacy of surfactant and emulsion was investigated by determining the minimum amount of UV light (MAUL) to induce a black point on the back of hairless mice (HRM2). The mean MAUL of PARSOL, OE20CA, and emulsion stabilized with TW20CA was $1046.5mJ/cm^2$, $1163mJ/cm^2$, and $1308.5mJ/cm^2$, respectively. The high UV-protecting efficacy of the emulsion could be ascribed to not only the UV-absorbing property of cinnamoyl group but also the UV-scattering property of the oil droplets.

• Proceedings of the KIEE Conference
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• 2001.11a
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• pp.182-185
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• 2001

A photoalignment material based N-(phenyl)maileimide were synthesized and the liquid crystal (LC) aligning capabilities on the photopolymer layer were studied. A goof LC alignment with UV exposure on the PM15CA(N-(phenyl)maileimide with 5-carbon chain cinnamoyl group) can be obtained However, the LC alignment defects were observed on the PM13CA (N-(phenyl)maileimide with 3-carbon cam cinnamoyl group) and PMIF (N-(Phenyl)maileimide 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 aliging ability on the photopolymer layer based N-(phenyl)maleimide depends on the side chin length of photopolymer.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.05a
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• pp.189-192
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• 2005

We have investigated the EO characteristics generation of pretilt angle for a nematic liquid crystal (NLC) alignment with photoalignment method on three kinds of photopolymer surfaces using polymer substrates. The LC homogeneous alignment were observed on the PMI3CA (N-(phenyl)maleimide with 3-carbon chain cinnamoyl group) and PMIF (N-(phenyl)maleimide including fluoro cinnamoyl group). However, the homeotropic alignment on the PMI5CA(N-(phenyl)maleimide with 5-carbon chain cinnamoyl group) was obtained. Also, EO characteristics of the flexible photoaligned TN-LCD using PMIF surface are better than that of the flexible TN-LCD using PMI3CA surface. Also, the stable EO performances of flexible photoaligned VA-LCD using the PMI5CA surface was observed.

• YAKHAK HOEJI
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• v.45 no.1
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• pp.7-15
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• 2001

For the purpose of defining the effects of N-acyl groups on the anticonvulsant activities of N-acyl-$\alpha$-amino-glutarimides, various (R)- and (S)-N-acyl-$\alpha$-aminoglutarimide were prepared from the corresponding N-Cbz-glutamic acid and were evaluated their anticonvulsant activities in the MES and PTZ test, including their neurotoxicities. Among the tested compounds, only (R) N-cinnamoyl-$\alpha$-amino-N-methylglutarimide showed anticonvulsant activity in the MES and PTZ test. And the other tested compounds was active in the only PTZ test. The order of anticonvulsant activities in the PTZ test was as followes; for the (R) series, N-4-methoxycinnamoyl = cinnamoyl > N-4-nitrobenzoyl > N-benzoyl > N-phenylacetyl; for the (S) series, N-4-methoxycinnamoyl = N-3-nitrobenzoyl > N-4-nitrobenzoyl = N-cinnamoyl = N-phenylacetyl. From the above results, it was conceivable that the substituted N-acyl group had important effects on the anticonvulsant activities of these compounds. However stereoisomeric deferences in the anticonvulsant activities were not exhibited clearly.

• Journal of the Korean Chemical Society
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• v.10 no.4
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• pp.166-174
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• 1966

The multistep mechanism of photosensitized curing reaction cinnamoylated photosensitive polymer is proposed from the energy level diagram of cinnamic acid and sensitizer, and from the fact that excess of sensitizer brings the sensitivity to a limiting value etc. Various factors which have effects on the ability of sensitizer are also discussed. The mechanism involves following steps: activation to the first excited singlet states of cinnamoyl group(C) and sensitizer(S) by their absorption of photon, their intersystem crossing to the lowest triplet state, bimolecular internal quenching by formation of excimer of sensitizer, triplet excitation energy transfer and intermolecular addition between cinnamoyl group in ground state and that in triplet state. The rate equation derived from this mechanism is $-\frac{d[C]}{dt} = \frac{K_1[C]}{K_2 + [C]}[\frac{I^c_{abs}}{K_3 + [S]} + \frac{K_4[C]}{(K_5 + [C])(K_6 + [S])}(I^s_{abs} + \frac{K_7I^c_{abs}[S]}{K_8 + [S]})]$ where $I^c_{abs}\;and\;I^s_{abs}$: the rates of absorption of photon by cinnamoyl group and sensitizer $K_n$: Constants. It is proved with the cinnamate of poly(glyceryl phthalate)(PGC) in the absence of sensitizer using the infrared analytical method and successfully applied for the experimental data reported on the effects of the degree of cinnamoyl esterification and the concentration of sensitizer upon the sensitivity.