• Journal of the Korean Crystal Growth and Crystal Technology
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• v.25 no.3
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• pp.105-110
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• 2015

The fiber-reinforced endodontic posts were prepared using a photocurable resin and a glass fiber. The mechanical property of the posts increased with increasing density of glass fiber and the micro-pores in the post were removed by a vacuum impregnation process. To improve the interfacial adhesion between glass fiber and polymer, silane coupling agent was used. The surface treatment of glass fiber increased the surface wettability of resing on glass fiber and increased the adhesion property with resin, consequently improved the mechanical property of posts.

• Proceedings of the Korean Fiber Society Conference
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• 2003.10b
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• pp.189-190
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• 2003

섬유강화 복합재료의 사용이 점점 증가함에 따라 구조용 및 내장재 등으로 사용된 수명이 다한 섬유강화 복합재료의 사용후 폐기가 문제가 되고 있다. 특히, 자동차 부품, 건축자재 및 전기절연재 등으로 가장 많이 사용되는 유리섬유 복합재료의 폐기물이 급격히 증가하여 환경 오염문제가 심각해지고 있어서, 환경 친화적인 새로운 복합재료에 대한 필요성이 제기되어 왔다. 따라서 본 연구에서는 천연섬유를 이용한 천연섬유/생분해성 수지계 복합소재를 대상으로 환경적합성이 우수하고 자연환경에서 완전한 생분해성을 가지며, 유리 섬유복합재료를 대체할 물성이 우수한 새로운 Biocomposite를 개발하고자 하였다. (중략)

• Composites Research
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• v.33 no.6
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• pp.346-352
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• 2020

In mobility industries, the use of thermoplastic composites increased dynamically. In this study, the mechanical and impregnation properties of continuous glass fiber (GF)/polypropylene (PP) composite were evaluated with different GF contents. The GF/PP commingled fiber was manufactured with different GF contents and continuous GF/PP composite was manufactured using continuous compression molding process. Tensile, flexural, and impact test of specimens were evaluated with different GF contents. The fracture behavior of specimens was proved using field emission-scanning electron microscope images of fracture area and impregnation property was evaluated using dynamic mechanical analyzer and interlaminar shear strength. Finally, the GF/PP composite was the optimized mechanical and impregnation properties using 50 wt.% GF/PP commingled fiber.

• Journal of the Korean Wood Science and Technology
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• v.36 no.4
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• pp.19-25
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• 2008

This study was carried out to investigate the bending strength properties of the unreinforced glulam beams and the GFRP laminated glulam beams according to the volume ratio of GFRP. The 7-layer glulam beams ($10cm(b){\times}14cm(h){\times}180cm(l)$) were manufactured, using Larch (Larix kaempferi Carr.) laminae ($2cm(h){\times}10cm(b){\times}360cm(l)$), which were dried to the moisture content of 8% and specific gravity of 0.54. GPRP of 0.1 and 0.3 cm was reinforced between the outmost layer of bottom and next layer. When the glulam beams were reinforced with GFRP at the volume ratio of 0.7% and 2.1%, respectively, the bending strength was increased by 12% and 28%, respectively, in the reinforced beams than in control glulam beams. Also, the GFRP reinforced layer of the glulam beams with GFRP laminations blocked the progression of rupture, and the unbroken part held about 90% of the bending strength. In the results of glue joints test, the block shear strength is higher than $7.1N/mm^2$, the standard of KS F3021, and in the result of delamination, the adhesive strength is good as the water soaking and boiling delamination was less than 5%.

• Journal of dental hygiene science
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• v.10 no.6
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• pp.445-450
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• 2010

The aim of this study was to evaluate the effect according to the fiber type and combination on the reinforcement of heat-polymerized denture base resin. The heat-polymerized resin(Vertex RS, Dentimax, Netherlands) was used in this study. Glass fiber(GL; ER 270FW, Hankuk Fiber Glass, Korea), polyaromatic polyamide fiber(PA; aramid; Kevlar-49, Dupont, U.S.A.) and ultra high molecular weight polyethylene fiber(PE, polyethylene; P.E, Dong Yang Rope, Korea) were used to reinforce the denture base resin specimens. The final size of test specimen was $64mm{\times}10mm{\times}3.3mm$. The specimens of each group were stored in distilled water at $37^{\circ}C$ for 50 hours before measurement. The flexural strength and flexural modulus were measured by an universal testing machine(Z020, Zwick, Germany) at a crosshead speed of 5 mm/min in a three-point bending mode. In this study, all fibers showed reinforcing effects on denture base resin(p<0.05). In terms of flexural strength and flexural modulus, glass fiber 5.3 vol.% showed most effective reinforcing effect on heat polymerized denture base resin. For flexural modulus, PA/GL was the highest in denture base resin specimen for hybrid FRC using two combination (p<0.05). Glass fiber 5.3 vol.% and PA/GL are considered to be applied effectively in reinforcing the heat polymerized denture base resin.

• The magazine of the Korean Society for Advanced Composite Structures
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• v.3 no.1
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• pp.28-32
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• 2012

• Composites Research
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• v.34 no.1
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• pp.1-7
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• 2021

Fiber-reinforced thermoplastic composites are applied to transport industries to lightweight of body, and applications will be expanded gradually. In this study, the impregnation and mechanical properties of continuous glass fiber (GF) reinforced polycarbonate (PC) composites were evaluated with different molecular weights of PC. The continuous GF reinforced PC composite were prepared by using GF fabric and PC film via continuous compression molding method. The melting flow index and tensile strength of PC matrix were evaluated with different molecular weights. Mechanical properties (tensile, flexural, and compressive) and pore rate of GF/PC composite were evaluated with different molecular weights of PC. The fracture behavior was analyzed to fracture surface of GF/PC composite using FE-SEM images. As these results, it was condition of representing the best mechanical property that the GF/PC composite was prepared by using PC of 20,000 g/mol as matrix.

• Journal of Korea Foundry Society
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• v.27 no.6
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• pp.258-262
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• 2007

단섬유강화 고분자 복합재료의 고온압축 프레스 성형 시 유리섬유의 유동을 지배하는 인자인 유리섬유와 모재의 유동성에 관하여 연구하기 위하여 ?h트 스트랜드의 교차각도를 $30^{\circ},\;45^{\circ},\;60^{\circ}$로 배향하여 모재와 적층시킨 다음 열압축프레스를 사용하여 1차로 시트를 제작하고, 이 제작된 시트를 가열로로 가열하여 열압축프레스로 2차 고온압축 프레스 성형한다. 여기서, 압축속도와 압축비를 변화시켰을 때 발생되는 유리섬유의 배향에 관한 실험결과를 고찰한다.

• Polymer(Korea)
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• v.24 no.4
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• pp.459-468
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• 2000

To improve the mechanical properties of fiber-reinforced polymer matrix composites, laminated composites plates were fabricated using different matrix resins and glass or aramid fibers. The effect of matrix resin system were evaluated by tensile, flexural strength measurements. In the case of surface treated aramid fiber and unsaturated polyester resin composite, maximum flexural properties were observed in the composite prepared from the glass fiber treated with 0.5 wt% silane coupling agents. Vinylester resin composites show the highest tensile properties and isophthalic polyester composites have the highest flexural properties among the unsaturated polyester resin composites studied. The relationship between overlap laminated composites plates and mechanical properties of polymer composites is also investigated in order to improve mechanical properties of glass fiber and unsaturated polyester resin composites.

• Composites Research
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• v.31 no.1
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• pp.8-11
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• 2018

Sheet molding compound (SMC) is one of the most economical fiber reinforced composite fabrication processing for automotive applications. In this study, we studied the optimum formulation for the production of SMC which shows low specific gravity without lowering the mechanical properties by using glass bubble (GB) which is a low specific gravity filler and glass fiber (GF) as a reinforcing material. The tensile strength increased with the increase of the GF in the SMC, and the specific gravity decreased with the increase of the GB. The synergistic effect of improving the mechanical properties as the specific gravity is lowered is found in the optimum formulation. The synergy effect was confirmed by the internal structure analysis that the dispersion effect of the crack propagation of the GB and the improvement of the binding force between the fiber and the matrix due to the incorporation of the GB.