• Elastomers and Composites
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• v.55 no.1
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• pp.6-12
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• 2020

Poly(ethylene-co-vinyl acetate) compounds and vulcanizates containing dicumyl peroxide (DCP) (HD) were prepared, and the curing agent and reaction products were analyzed using gas chromatography/mass spectrometry (GC/MS). Samples containing trially cyanurate (TAC) and DCP (HDT) were also prepared and analyzed. Some raw DCP were decomposed in the injector region of GC to produce acetophenone. DCP was detected in the HD compound but was not observed in the HD vulcanizate, and instead acetophenone and 2-phenyl-2-propanol were detected. Both DCP and TAC were observed in the HDT compound but not in the HDT vulcanizate, where acetophenone and 2-phenyl-2-propanol were detected. Thus, some of the DCP decomposed during the compounding process. The formation mechanism for acetophenone and 2-phenyl-2-propanol during the crosslinking reaction was identified, and differences in the crosslinking reactions of HD and HDT compounds were discussed.

• Macromolecular Research
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• v.12 no.1
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• pp.141-143
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• 2004

We have investigated the dynamic mechanical behavior of ultra-high molecular weight polyethylene (UHMWPE) irradiated with varying doses of gamma rays. A relaxation peak in the loss factor curve, which has not been reported previously in the literature, is observed at a temperature above the crystal melting temperature. The peak is unique to UHMWPE and appears to be related to the high degree of entanglement. Because the temperature and intensity of the peak are reduced by irradiation-induced chain scission and crosslinking, respectively, we believe that the peak is associated with disentanglement relaxation. The behavior of the storage modulus in the melt state agrees with the classical theory of rubber elasticity.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.347-349
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• 1999

We have fabricated insulating thin films using p-hexadecoxyphenol(p-Hp) that was formed phenol-formaldehyde resin of crosslinked structure from reaction with formaldehyde by LB technique. For fabricated MIM device, the possibility for insulating layers of electronic were investigated by electrical properties of their LB films according to crosslinking of LB films current-voltage (I-V) properties and frequency-capacitance (C-F) characteristics. We have provided evidence for the high insulating performance of phenol-formaldehyde thin films by the LB method. Conductivity of their LB films was as follows: pure water > 1 % aq. Formaldehyde > heat treatment, in the current-voltage (I-V) characteristics. It is demonstrated that insulation properties of crosslinked p-HP LB films were improved. In capacitance-frequency properties, the heat-treated p-HP LB films for crosslinking showed a low relative dielectric constant.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.5
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• pp.420-425
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• 2000

Crosslinked polyethlyene/silane crosslinked polyethylene(XLPE/SXLPE) blends were prepared by a twin screw extruder and their water tree growing electrical breakdown and crossinking characteristics were investigated. The water tree characteristics of XLPE were improved by the addition of SXLPE when samples were crosslinked only by the thermorolysis of DCP (dicumyl peroxide). However steam curing process was not good for water tree characteristics. It was also found that the rate of water tree growing of XLPE/SXLPE blend increased when the content of SXLPE was 50%. AC breadown strength slightly increaed by the addition of SXLPE to XLPE when samples were crosslinked only by the thermorolysis of DCP. It was also found that the degree of crosslinking of XLPE/SXLPE blends were higher than that of XLPE in the case of the content without steam crosslinking process.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.11a
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• pp.140-143
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• 1997

It was investigated that space charge characteristics of EPDX/LPE laminates as a function of interfacial condition. There were no effects in charge accumulation characteristics at EPDM/XLPE laminate samples which were pasted with silicone oil and silicone grease. But when the crosslinking coagent (TMPTA) was pasted in laminate samples, there was no space charge in interface of EPDE/XLPE laminate and no effects in the laminate sample pasted with silicone grease dissolved crosslinking coagent. In the coupling agent pasted EPDhyXLPE laminate sample, space charge was accunlulated in XLPE side caused by coupling agent.

• Proceedings of the KIEE Conference
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• 2002.11a
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• pp.179-182
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• 2002

XLPE compound have used for insulation of 22.9(kV) power cable. But tree retardant power cable has developed and is going to br used commonly. TR XLPE compound retard production and growth of water tree. In this paper, tensile strength, elongation at break, degree of crosslinking, lightning impulse test, AC breakdown test, cyclic aging for 14days and accelerated water treeing test of TR XLPE insulated power cable were examined according to the KEPCO buying spec. & AEIC CS 5-94 standards. before and after As the result, tensile strength, elongation at break and degree of crosslinking test results of TR XLPE insulation were higher than requirement values. After accelerated water treeing test for 120 days, 240 days and 360 days, AC breakdown voltages were not decreased for accelerated water treeing aging duration

• Journal of Photoscience
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• v.6 no.3
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• pp.145-151
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• 1999

The use of O-carbamoyloximes as photobase generators was investigated. $\alpha$-Meth-ylbenzilydeneamino phenylcarbamate(2a) and $\alpha$-methyl benzilydeneamino cyclohexylcarbamate(2b) were prepared by the reaction of phenyl or cyclohexyl isocyanates with acetophenone oxime , respectively. Aniline, phenylhydrazine and N, N'-diphenylhydrazine were detected in thephotolysis of 2a and cyclohexylamine and cyclohexylhydrazine in the photolysis of 2b. A monomer having pendant carbamoyloxyimino groups (BGM) was prepared by the reaction fo methancryloyloxyethyl iocyanate with acetophenone oxime, and copolymerized with styrene. The BGM copolymer films turned insoluble on UV irradiation, and the degree of insolubilizationwas increased by post-baking. The photocrosslinking was thought to be due to coupling of resulting pendant aminyl radicals, and the thermal crosslinking was due to association of resulting amino and hydrazino groups by hydrogen bonding. The introduction of epoxy groups into polymer increased the degree of thermal crosslinking by post-baking.

• Journal of the Korea Organic Resources Recycling Association
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• v.19 no.2
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• pp.16-21
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• 2011

Immobilization of biosorbent is very important for application to real wastewater treatment process because biosorbent itself does not have enough tough structure. Therefore, resent research on heavy metal biosorption using biomass has been focused on its efficient immobilization method. To improve the mechanical strength of freely biosorbent, many immobilization methods have been suggested for applications to the biosorbent such as microorganisms or polysaccharides. In this study, various immobilization methods such as adsorption, covalent binding, entrapment, encapsulation, and crosslinking will be introduced.

• Elastomers and Composites
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• v.54 no.3
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• pp.201-208
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• 2019

Superabsorbent hydrogel (SAH) is a lightly crosslinked hydrophilic functional polymer material comprising a flexible chain structure, which can absorb and retain high amounts of water or aqueous fluids even under high pressure. Therefore, it is important to improve their characteristics such as absorption performance, residual monomer content, and water permeability. SAH nanocomposites were prepared using clay mineral as an inorganic filler and the influence of post-treatment processes such as quenching and aging process on their properties was studied. In addition, surface-crosslinking process was applied to improve the absorption performance associated with mechanical properties and water permeability. The structure of the SAH was characterized using attenuated total reflectance Fourier transform infrared spectroscopy, X-ray diffraction analysis, and scanning electron microscopy.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.236.2-236.2
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• 2003

For the purpose to treatment of skin disease genipoiside and hydrolyzed product of Gardeniae Fructus were studied on skin permeation and crosslinking of a biologied tissue. Geniposide was hydrolyzed to genipin by ${\beta}$-glucosidase and the rate of hydrolysis was rapid on the condition of high temperature of medium and high concentration of ${\beta}$-glucosidase. The permeation enhancing effects of geniposide and genipin under cream and gel preparations were tested using Franz type diffusion cell and the skin of hairless mouse. (omitted)