• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 봄 학술발표회 논문집
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• pp.195-197
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• 2003

Polymer layered silicate nanocomposite has become an important area of polymer research becaues of its predominant properties in mechanical and thermal properties. Polymer layered silicate nanocomposites show outstanding improvements in tensile strength and modulus, heat distortion temperature, gas and liquid permeability, solvent resistance, and so on. But These improved properties are realized only when silicate particles are well dispersed in polymer matrix. (omitted)

• 한국결정성장학회지
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• 제13권5호
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• pp.217-221
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• 2003

본 연구에서는 섬유의 표면 거칠기를 조사하기 위하여 tetraethyl orthosilicate, 에탄올, 증류수 및 염산의 혼합 용액을 이용하여 실리케이트 섬유를 제조하였다. $80^{\circ}C$에서 증발시킨 점성용액으로부터 섬유를 인상하여 제조하였으며, 건조된 겔 섬유는 건조공기를 흘려보내며(flow rate = ∼200 m1/min) $1000^{\circ}C$, $1100^{\circ}C$, $1200^{\circ}C$ 및 $1300^{\circ}C$로 60분간 최종열처리를 행하였다 열처리된 섬유의 결정화도는 X-선 회절 $\theta$-2$\theta$ 분석을 통하여 행하였으며, 표면 특성을 조사하기 위하여 전계 방사 주사 전자현미경과 원자간력 현미경을 이용하였다. $1300^{\circ}C$로 열처리된 실리케이트 섬유는 높은 root mean square 거칠기 값을 보였으며, 비교적 불균질한 표면 구조를 가지고 있었다.

• 한국광학회:학술대회논문집
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• 한국광학회 2008년도 하계학술발표회 논문집
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• pp.411-412
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• 2008

The chromatic dispersion of the germano-silicate optical fiber incorporated with Si nanocrystals was determined with the aid of simulation and demonstrated using experiments, which showed dependence of the launched power and the pump wavelength due to optical nonlinearity of the fiber.

• 한국농공학회논문집
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• 제46권3호
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• pp.65-72
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• 2004

Modern underground and tunnel works that the wet type shotcrete is getting widely designed and applied in a large scale project. Further to its applications, the needs of improving the performance of the shotcrete, such as new and developed additives and accelerators fur increasing the performance of shotcrete, become the most important issue in the field. The main objective of this study evaluated to performance of steel fiber reinforced shotcrete using alkali free based accelerator for the durability and high quality of shotcrete. The major test variables are accelerator type and its dosage. One type silicate based accelerator and one type aluminate based accelerator and one type alkali free based accelerator were used. The dosage of accelerators is determined by the manufactures and laboratory test condition. Compressive strength test results showed that the dosage of silicate and aluminate based accelerators caused reduction of mechanical properties of shotcrete. Compressive strength of alkali free based accelerator is more stable than of silicate and aluminate based accelerators. Also, according to the compressive strength and flexural test results, it was found that steel fiber reinforced shotcrete used alkali free based accelerator could attain significant improvement in the mechanical and flexural performance.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1994년도 추계 학술발표회
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• pp.104-104
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• 1994

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 가을 학술발표회 논문집
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• pp.59-62
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• 2003

Nanocomposites are composite materials consisting of polymer matrix and layered silicate that are interacted in nanometer scale. Layered silicate based polymer nanocomposites have attracted considerable attention because of their excellent properties. Nanocomposites usually exhibit improved performance properties compared with conventional composites due to their unique phase morphology and improved interfacial properties. (omitted)

• Fibers and Polymers
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• 제3권3호
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• pp.103-108
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• 2002

The viscosity effect of matrix polymer on melt exfoliation behavior of an organoclay in poly($\varepsilon$-caprolactone) (PCL) was investigated. The viscosity of matrix polymer was controlled by changing the molecular weight of poly($\varepsilon$-eaprolactone), the processing temperature, and the rotor speed of a mini-molder. Applied shear stress facilitates the diffusion of polymer chains into the gallery of silicate layers by breaking silicate agglomerates down into smaller primary particles. When the viscosity of PCL is lower, silicate agglomerates are not perfectly broken into smaller primary particles. At higher viscosity, all of silicate agglomerates are broken down into primary particles, and finally into smaller nano-scale building blocks. It was also found that the degree of exfoliation of silicate layers is dependent upon not only the viscosity of matrix but thermodynamic variables.

• Fibers and Polymers
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• 제4권3호
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• pp.97-101
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• 2003

Polymer/silicate nanocomposites were prepared via two-step manufacturing process: a master batch preparation and then mixing with matrix polymer. A hybrid of PMMA and Na-MMT with exfoliated structure was first prepared by emulsion polymerization of MMA in the presence of Na-MMT. For the case that SAN24, miscible with PMMA, is used as matrix, we could prepare a nanocomposite with exfoliated structure. However, SAN31 nanocomposite shows the aggregation and/or reordering of the silicate layers due to the immiscibility between SAN31 and PMMA.

• 한국세라믹학회지
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• 제34권5호
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• pp.491-499
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• 1997

High flexible lightweight composites containing tobermorite as a main mineral is produced using various amorphous silicates, lime, cement and fibers. Here, Mechanical properties of the composites were studied by observing microstructures of hydrates and fibers. Amorphous silicates having better hydraulicity retarded the crystallization of tobermorite due to better formation of C-S-H gel in water bath curing, but, difficult conversion from C-S-H gel to tobermorite in hydrothermal reaction. In the low molar ratio of CaO/SiO2 (0.67), faster crystalization was observed dued to more impurities such as Al2O3 alkali, resulting in improving mechanical properties due to small crystal size and many contact points. It was identified that a lot of calcium silicate hydates formed at surface of pulps increase bonding strength and the crack-resistance of matrix in the composites, but decrease hardness and compressive strength. The choice of amorpous silicates having better hydraulicity, low CaO/SiO2 adding each fibers bellow about 5% in the raw mixs and lower molding pressure should be needed at improve mechanical properties of composites.

• 한국건설순환자원학회논문집
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• 제3권1호
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• pp.80-86
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• 2007

In this study we experimented setting time and basic properties as waste wood fiber and sodium silicate substitution rate to reuse waste wood fiber produced in construction field to wood chip board. To do this construction waste woods were crushed with the size less than 10mm, mixed with the rate of 1:2, 2.5, 3, and added sodium silicate with the rate of 0, 5% of cement content. The results are as follows. As the substitution rate of construction waste wood was increased delay of setting time was also increased, and the batch of adding 5% accelerator had a 13~17 hours faster setting time than non accelerator batch. The compressive strength was lower as wood substitution rate was higher, and as the specific gravity was higher, the strength was also higher. As wood substitution rate was higher, heat conductivity was lower, and as specific gravity was higher, heat conductivity also was higher.