• Fire Science and Engineering
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• v.25 no.6
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• pp.190-195
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• 2011

Effects of ethylene-propylene diene monomer (EPDM)/polypropylene (PP), zinc oxide, stearic acid, and clay on the combustive properties based on EPDM/PP were investigated. The EPDM/PP/clay nanocomposites was compounded to prepare specimen for combustive analysis by cone calorimeter (ISO 5660-1). It was found that the combustive properties in the nanocomposites decreased due to the fire resistance compared with unfilld EDPM/PP. The nanocomposites showed the lower peak heat release rate (PHRR) than that of virgin EPDM/PP, while stearic acid for softening ruber increased the mean heat release rate (MHRR) by itself, combustible.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1994.04a
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• pp.5-8
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• 1994

고분자 물질은 저분자량의 유기 단량체들이 화학 공유 결합으로 연속적으로 연결된 거대 분자 구조를 갖는다. 고분자 사슬로 연결된 단량체들은 힘의 장 의 지배하에 열에너지에 따라 지속적으로 운동을 한다. 이와같은 단량체들의 운동은 국부적으로 제한되나 온도가 증가되어 유리 전이온도 이상이 되면 분자전체에 상당하는 운동으로 발전하게 된다. 이때 소음 및 진동 에너지는 효과적으로 흡수되어 열에너지로 발산된다. 본고에서는 유리 전이온도에서의 고분자 재료의 특성가 실제 소음 및 진도제어시 고려해야할 고분자 재료의 특성에 관해 알아본다.

• Journal of the Korean Applied Science and Technology
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• v.34 no.2
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• pp.203-209
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• 2017

The propenyl ether-type monomers which are applicable for cationic photo-polymerization were synthesized by the condensation reaction of mono and di-functional alcohol with allyl bromide. To examine photo-curable reactivity, these monomers were combined with cationic photoinitiator to prepare coating composition. As a result, the initial rate of polymerization of POMB in mono propenyl ether type was 10.2, which was relatively lower than BPOB in di-propenyl ethers type. However, POMB containing 1.5mol% photoinitiator almost quantitatively reacted within 90 seconds. In addition, Sulfonium salt type photo-initiators containing long-alkyl group showed good solubility with monomers and apperaed to have comparatively higher rate of polymerization and conversion ratio when applying DPSA and DPST which have high acidity on all monomers.

• Polymer(Korea)
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• v.32 no.6
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• pp.603-609
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• 2008

The purpose of this study is to clarify the effect of the monomer ratio on properties of the polymer-modified mortars using methyl methacrylate-butyl acrylate (MMA/BA) latexes, and to obtain basic data necessary to develop appropriate latexes for cement modifiers. From the test results, the total pore volume of polymer-modified mortars using MMA/BA latexes is linearly reduced with an increase in the bound MMA content and increased in the polymer-cement ratio. In general, the superior flexural and compressive strength of polymer-modified mortars using MMA/BA latexes is obtained at a bound MMA content of 70 or 80 percent and a polymer-cement ratio of 15%. And, the water absorption and chloride ion penetration depth are greatly affected by the polymer-cement ratio rather than the bound MMA content.

• Applied Chemistry for Engineering
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• v.10 no.1
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• pp.138-142
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• 1999

Imide-containing diamine and dicarboxylic acid monomers, N-(4-aminophenyl)-4-aminophthalimide(APAP), N-(4-carboxyphenyl)-4-carboxyphthalimide(CPCP), N,N'-oxydiphenylenebis(4-aminophthalimide)(ODPAP) and N,N'-oxydiphenylenebis(4-carboxyphthalimide)(ODPCP) were prepared. Poly(amide-imide)s were prepared by condensation reaction of the diamine and the dicarboxylic acid monomers. Poly(amide-imide)s were also prepared from the diamine monomers and aromatic acid chlorodes such as terephthaloyl chloride and isophthaloyl chloride. The polymers possess inherent viscosity of 0.18~0.67 dL/g and brittle films were cast from NMP/LiCl solution. The poly(amide-imide)s are easily soluble in NMP/LiCl and also partially soluble in polar aprotic solvents such as DMF, DMSO, NMP and DMAc even at $80^{\circ}C$. DSC traces of polymers showed no glass transition temperature and melting temperature, and TGA traces showed a 10% weight loss at $500^{\circ}C$.

• Polymer(Korea)
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• v.37 no.2
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• pp.148-155
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• 2013

The purpose of this study is to clarify the effect of the emulsifier ratio on the properties of the polymer cement mortars based on styrene-butyl acrylate (S/BA) latexes, and to obtain necessary basic data to develop appropriate latexes for cement modifiers. The polymer dispersions for cement modifiers was synthesized using styrene and butyl acrylate. Polymer cement mortars based on S/BA latexes were prepared with various monomer and emulsifier ratios, and their water-cement ratio, air content, flexural and compressive strengths, water absorption and chloride ion penetration were tested. From the test results, the maximum flexural and compressive strengths of polymer cement mortars based on S/BA latexes were obtained at a bound styrene content of 60% and an emulsifier ratio of 6%. Also, the water absorption and chloride ion penetration depth are greatly affected by the polymer-cement ratio rather than the bound styrene and emulsifier content. Accordingly, it is judged that S/BA latexes can be used place of the conventional polymer dispersions of cement modifier.

• Nuclear Engineering and Technology
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• v.4 no.4
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• pp.301-305
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• 1972

The polymerization rates of monomer or monomer mixture impregnated with catalyst into domestic soft woods such as pinus densiflora, pinus rigida and poplus deltoides e. t. c. were measured. The results were compared with those obtained by radiation curing method and the following conclusions were derived ; (1) Pinus densiflora and pinus rigida are superior to the poplus deltoides, and methyl methacrylate(M. M. A. ) is more effective than other monomers as far as the polymerization rates are only taken into account. (2) The polymerization rate of vinyl acetate is generally slow. And the polymerization rate of the monomer is the slowest in case of being impregnated into poplus deltoides. However, the polymerization rate of the comonomer composed of vinylacetate and M. M. A. is the fastest among the other monomers or monomer mixtures in woods regardless of the curing method. (3) The general trend of polymerization of monomer in wood is similar to that of monomers themselves in both curing methods if the woods contain not much resin.

• Journal of Adhesion and Interface
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• v.1 no.1
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• pp.23-29
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• 2000

Surface modification of hydrophobic polymeric materials to be hydrophilic or to have specific functional groups is of great importance for a diversity of applications of the materials. In this study, polyethylene (PE) film surfaces were modified by vapor phase photografting of hydrophilic vinyl monomers with different functional groups. The functional monomers were introduced on PE films by introducing the monomers in vapor phase using a vapor phase photografting apparatus designed by our laboratory. Functional monomers used were acrylic acid (negatively chargeable), acrylamide and allylalcohol (neutral), and allylamine and N,N-dimethyl aminopropyl acryamide (positively charged). The functional monomer-grafted PE film surfaces were characterized by the measurement of water contact angles and the attenuated total reflectance Fourier-transform infrared spectroscopy. The vapor phase photografting seems to be effective means for introduction of various functional groups onto polymeric substrates.

• Proceedings of the Korean Fiber Society Conference
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• 1999.04a
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• pp.86-89
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• 1999

• Information Display
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• v.10 no.1
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• pp.2-14
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• 2009