• Proceedings of the KIEE Conference
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• 2008.10a
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• pp.184-184
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• 2008

This paper presents the measurement of the mechanical property of PDMS (Polydimethylsiloxane) elastomer depending on volumetric mixing ratios of base polymer and curing agent and their hyperelastic material models.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.6
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• pp.14-20
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• 2009

• Macromolecular Research
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• v.11 no.3
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• pp.202-205
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• 2003

The reactive precursors, vinyl ethers, and epoxy-silicones, were synthesized. The vinyl ether monomers were prepared from primary alcohol and ethyl vinyl ether with mercury (II) acetate. The epoxy-functionalized silicones have been achieved by the controlled, rhodium-catalyzed, chemoselective hydrosilation of vinyl ether with siloxanes or silane. It was shown that the hydrosilation proceeds exclusively at the vinyl ether group of alkenyl vinyl ether without participation at the alkenyl group. The photoinduced cationic polymerization of these monomers was studied and found to be all highly reactive.

• Macromolecular Research
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• v.12 no.1
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• pp.11-21
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• 2004

Toughening of epoxy resins for improvement of crack resistance has been the subject of intense research interest during the last two decades. Epoxy resins are successfully toughened by blending with a suitable liquid rubber, which initially remains miscible with epoxy and undergoes a phase separation in the course of curing that leads to the formation of a two-phase microstructure, or by directly blending preformed rubbery particle. Unlike the situation for thermoplastics, physical blending is not successful for toughening epoxy resins. Recent advances in the development of various functionalized liquid rubber-based toughening agents and core-shell particles are discussed critically in this review.

• Elastomers and Composites
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• v.29 no.5
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• pp.431-435
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• 1994

For recycling of the waste tires, polyurethane binder mixed with the scrapped rubber powders which obtained from tread part of waste tire. This study covered the effect of the binder contents on the mechanical properties of the blend. We also studied the change of the properties after aging on properties compared with those of before aging. The curing reaction of the binder was also investigated in this study. We obtained conclusions the suitable binder content was 15phr in this system.

• Geomechanics and Engineering
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• v.8 no.3
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• pp.361-375
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• 2015

Constructions over soft and loose soils are one of the most frequent problems in many parts of the world. Cement and cement-lime mixture have been widely used for decades to improve the strength of these soils with the deep soil mixing method. In this study, to investigate the freeze-thaw effect of sand improved by polymers (i.e., styrene-acrylic-copolymer-SACP, polyvinyl acetate-PVAc and xanthan gum) and fly ash, unconfined compression tests were performed on specimens which were exposed to freeze-thaw cycles and on specimens which were not exposed to freeze-thaw cycles. The laboratory test results concluded that the unconfined compressive strength increased with the increase of polymer ratio and curing time, whereas, the changes on unconfined compressive strength with increase of freeze-thaw cycles were insignificant. The overall evaluation of results has revealed that polymers containing fly ash is a good promise and potential as a candidate for deep soil mixing application.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.420-421
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• 2011

In this study, Instead of using urethane curative systems, which have long been used as solid propellants, a triazole curative system has been introduced into a new binder recipe in which azide groups in the polymer react with triple bonds of a dipolarophile curative.

• Journal of the Korean Graphic Arts Communication Society
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• v.13 no.1
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• pp.93-104
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• 1995

Liquid crystal-polymer composite(LCPC) films promising new materials for both projection displays and vision product. LCPC films consist of a continous liquid crystal phase embedded in a three- dimensional network of polymer matrix. The liquid crystal in these LC phases can be elecrtrically switched giving rise to an opaque scattering off-stats and a transparent, non-scatting on- stats. In this work. a premixture is composed of LC, UV-curable monomer and photonitiator. LCPC films are formed by photopolymerization induced phase separation from this premixture. In conclusion, structure and electro-optical properties of LCPC films strongly depends on the selection of monomer, LC content and curing rate.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.315-315
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• 2006

A variable surface coating with the potential to fulfill the requirements of industry will be presented. Via controlled radical polymerization methods from a functionalized Polymethylsilsesquioxane delivers an inorganic-organic block copolymer, which can be easily modified and tuned for different applications. Spin coated or dip coated on various substrates show promising results. By using different block copolymers the contact angle on a silicon wafer can be varied in a range of $90^{\circ}\;up\;to\;145^{\circ}$ After curing and complete condensation a perfect adhesion on glasses, plastics and metals is achieved.

• Elastomers and Composites
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• v.51 no.3
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• pp.181-187
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• 2016

Transparent acrylic pressure sensitive adhesives (PSAs) were successfully prepared by photopolymerization with 2-ethylhexyl acrylate (2-EHA) and 2-hydroxyethyl acrylate (2-HEA) as a default constituent and with isobornyl acrylate (IBOA) and N-(isobutoxymethyl)acrylamide (IBMA) as a variable constituent. The IBMA mole fraction effect in the acrylic PSAs was investigated on adhesion performances and the optical properties including 85/85 test as well as the characteristics (solid content, and molecular weight) of the PSA syrups were also investigated. Regardless increasing the IBMA mole fraction in the acrylic PSAs, the acrylic PSAs exhibited almost the same adhesion performance such as $180^{\circ}$ peel strength (~4.0 kg/25 mm) and probe tack (~0.27 kg). All the acrylic PSA samples also showed high transmittance (more than 91%), low haze (less than 1.0%) and low color-difference (less than 1.0) before and after 85/85 test.