• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.2
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• pp.142-151
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• 2007

Non-halogen flame retardant have been focus of extensive research because of environmental problem. Hexakisphenokycyclotriphosphazene was synthesized in order to use as the flame retardant of ABS resin. And using bisphenol A, bisphenol S, and resorcinol, the polymers which contained cyclophosphazene structure were synthesized in order to also use as the flame retardants of ABS resin. All of the synthesized polymers themselves got the excellent flame retardancy. And as the molecular weight of the compound were increased, the thermal stability was increased. But when the synthesized compounds were used as the flame retardants for ABS resin, the lower molecular weight compound in these compounds showed the better flame retardancy and the better physical properties of ABS resin. In case of using resorcinol, it showed the best flame retardancy.

• Journal of the Korean Graphic Arts Communication Society
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• v.29 no.1
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• pp.45-59
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• 2011

According as gradually increasing the demand for Eco-friendly products it has been progressed fairly development at a field of printing and printing inks. The Inks are used by soy oil beginning of ink industry for preventing environment. Now it is possible to make Eco-friendly inks with vegetable ester. So it is not necessary to use petroleum-based solvents for preventing environment. But There is some problems if using vegetable ester to inks. Vegetable ester has high solubility, it causes misting and low viscosity of the Inks. So resin is required high performance. Thus, in this paper, I studied about the properties variation of the Varnish and inks According to using the phenolic modified rosin ester and Soy oil Methyl esters. The compared in order of average molecular weight by the GPC method, rheological properties were found by rotational rheometer, and emulsion behavior were compared by high speed emulsification tester.

• Design & Manufacturing
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• v.17 no.3
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• pp.28-33
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• 2023

The conventional FRP (Fiber Reinforced Plastic) manufacturing process used thermoset resins for ease of molding but faced the issue of non-recyclability. To address these shortcomings, a new process utilizing thermal plastic resin was developed. However, due to the high viscosity of thermal plastic resin, problems such as fiber deformation and a reduced fiber volume fraction occurred during the high-temperature, high-pressure process. In this study, to overcome the limitations of the conventional process, fiber-reinforced composite materials were manufactured through in-situ polymerization using PLA (Poly L-Lactide) resin in the VA-RTM (Vacuum Assistance Resin Transfer Molding) process. The fiber volume of the produced specimens was calculated, and resin impregnation and porosity were confirmed through optical microscopy. Additionally, molecular weight analysis using GPC (Gel Permission Chromatography) demonstrated improvements over the conventional process and emphasized the essential requirement of temperature control.

• Polymer(Korea)
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• v.27 no.5
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• pp.493-501
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• 2003

Poly(methyl methacrylate) (PMMA) particles, denture base resin, were synthesized by suspension polymerization through control of polymerization conditions (stabilizer concentration, co-monomer concentration, and the agitation speed) and evaluated changes in molecular weight and particle size. We also investigated their mechanical properties of compression-molded samples which were from synthesized polymer powder mixed with methyl methacrylate (MMA) solution. under the condition of volumetric ratio as 2:1(PMMA powder and MMA solution). The results shows that the mechanical properties were mainly affected by particle size over 100 ${\mu}$m (in particle size) and by molecular weight under 100 ${\mu}$m (in particle size). From these results, we concluded that the most appropriate particle size of PMMA powder for heat-cured denture base resins is around 100 ${\mu}$m. and its molecular weight is around 300000 (M$\sub$n/).

• Proceedings of the KIEE Conference
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• 1988.07a
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• pp.315-318
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• 1988

THE STUDY ABOUT CHARACTERISTICS OF PHOTO RESIST ITSELF (MINIMUM RESOLUTION, DEPTH OF FOCUS MARGIN AND CRITICAL DIMENSION CONTROL LATITUDE) WAS DONE AND REPORTED. THREE TYPES OF PHOTO RESISTS WERE TESTED. THE FIRST IS THE LOW MOLECULAR WEIGHT PHOTO-RESIST SHOWING THE NARROW DISTRIBUTION OF MOLECULAR WEIGHT (LOW MOLECULAR WEIGHT CONTROL TYPE), THE SECOND IS A PHOTO-RESIST CONTAINING THE INNER CONTRAST ENCHANCEMENT MATERIAL (INNER CEM TYPE) AND THE THIRD IS A NORMAL PHOTO-RESIST (HIGH MOLECULAR WEIGHT TYPE). THE INNER CEM TYPE AND THE LOW MOLECULAR WEIGHT CONTROL TYPE PHOTO-RESIST ARE MORE IMPROVED PHOTO-RESISTS. IT PROVED THAT THE MINIMUM RESOLUTION WAS IMPROVED BY 0.2 - 0.3 um, THE DEPTH OF FOCUS MARGIN WAS IMPROVED BY 0.8 - 1.2 um AND THE C.D. CONTROL LATITUIDE WAS IMPROVED.

• Composites Research
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• v.30 no.3
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• pp.169-174
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• 2017

Demand of glass fiber reinforced composites (GFRC) increased with developing aircraft and defense industries using resin transfer molding (RTM) process to produce complex product. In this research, wetting, interfacial, and mechanical properties were evaluated with different Cross-linking Density by Molecular Weight of Hardener. Epoxy resin as matrices was used bisphenol-A type and amine-type hardeners with different molecular weight. Specimens were manufactured via RTM and wetting property of resin and glass fiber (GF) mat was evaluated to viscosity of epoxy and injection time of epoxy matrix. Mechanical property of GFRC was determined via flexural strength whereas interfacial properties were determined by interlaminar shear strength (ILSS) and interfacial shear strength (IFSS). The difference in mechanical property depends upon the fiber weight fraction (wt %) of GFRC by RTM as well as the different Molecular Weight of Hardener.

• Applied Chemistry for Engineering
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• v.17 no.2
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• pp.144-149
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• 2006

Non-halogen flame retardants have been the focus of extensive research because of environmental problems. Hexakisp-henoxycyclotriphosphazene was synthesized in order to use as the flame retardant of ABS resin. And using bisphenol A, the polymers containing a cyclotriphosphazene structure were synthesized in order to also use as the flame retardant of ABS resin. All of the synthesized polymers themselves had the excellent flame retardancy. And as their molecular weight and crosslinking density were increased, the thermal stability was increased. But when the synthesized compounds were used as the flame retardant for ABS resin, the lower molecular weight compound in these compounds showed the better flame retardancy and the better physical properties of ABS resin.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.610-617
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• 2000

The indigestible dextrin with high indigestible fraction was prepared by treating the enzyme hydrolysate of pyrodextrin with ethanol or strongly acidic cation exchange resin(UBK 530). Optimum conditions of ethanol treatment for preparing the indigestible dextrin from $\alpha-amylase$ and amyloglucosidase treated hydrolysate were determined based on the indigestible fraction, dietary fiber content, and yield. Ethanol was added 5-fold by weight to 30%(w/w) enzyme hydrolysate, and the mixture was kept at room temperature for 3 hr. Low molecular weight saccharides containing glucose and high molecular weight saccharides were separated by strongly acidic cation exchange resin. While initial enzyme hydrolysate by $\alpha-amylase$ and amyloglucosidase showed 43.6% of DPI(glucose) and 51.1% of DP4+(maltotetraose and over), the indigestible dextrin collected to 50% of initial enzyme hydrolysate by treatment of cation exchange resin showed 7.1% of DPI(glucose) and 91.2% of DP4+(maltotetraose and over). In conclusion, 44.5% of indigestible fraction of initial enzyme hydrolysate increased to 78.9% after separation of low molecular weight saccharides.

• Applied Chemistry for Engineering
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• v.4 no.3
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• pp.627-636
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• 1993

Anionic acrylic resin utilizing macromer(TBMA-g-MMA) copolymer was synthesized by preparing (TBMA) macromer using anionic living polymerization, followed by graft copolymerization with MMA macromer. To control the anionic site content in graft copolymer, the relative composition((TBMA) macromer/MMA ratio) of the graft copolymer was controlled at 7/3, 10/90, 15/85, 20/80, 30/70, 40/60, 50/50 in weight content. In the course of anionic living polymerization of(TBMA) macromer, broad molecular weight distribution (1.4~1.5) was obtained by using n-butyllithium-diphenyethylene initiatior system at $-78^{\circ}C$. To introduce the double bond at the end of chain in termination step, methacryloyl chloride was reacted after insertion of benzaldehyde as capping material. Moreover, TBMA parts in graft copolymer were hydrolyzed in the presence of p-toluenesulfonic acid catalyst, and neutralization of graft copolymer with triethylamine was granted acrylic resin to anionic site. Molecular weight and molecular weight distribution of(TBMA) macromer were determined by GPC, and the hydrolysis of TBMA with neutralization of acrylic resin were determined by IR and NMR. From water dispersion and stability point of view, stable dispersion state appeared at low molecular weight(TBMA) macromer with a small TBMA content as a result of scrutiny about the relation to TBMA content and branch length for(TBMA) macromer molecular weight in graft copolymer.

• Proceedings of the Korean Printing Society Conference
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• 2007.11a
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• pp.1-12
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• 2007

The rheological properties of an ink relate to its performance on the press and to the printing quality. So it is necessary to analyze the relationship between printability and the rheological properties of ink. Transfer rate of ink is one of the important factor deciding print quality. And it is concerned with rheological properties of ink. Thus, in this study, according to the molecular weight of rosin modified phenolic resin the rheological properties of ink were measured by rotational rheometer and then transfer equation of ink, density and gloss were mesured in order to examine the printability of ink.