• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2007.11a
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• pp.93-102
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• 2007

Biocomposite was organized with biodegradable polymer and natural fiber that has potential to be used as replacement for glass fiber reinforced polymer composite with the benefits of low cost, low density, acceptable specific strength, biodegradability, etc. Until now, non-wood fibers have been used as reinforcements of biocomposite which are all plant-based fibers. The present study focused on investigating the fabrication and characterization of biocomposite reinforced with red algae fiber. The bleached red algae fiber(BRAF) showed very similar crystallinity to the cellulose. It has high stability against thermal degradation (maximum thermal decomposition temperature of 359.3$^{\circ}C$) and thermal expansion. Biocomposites reinforced with BRAF have been fabricated by a compression molding method and their mechanical and thermal properties have been studied. The storage modulus and the thermomechanical stability of PBS matrix are markedly improved with reinforcing the BRAF. These results support that the red algae fiber can be used as an excellent reinforcement of biocomposites as "green-composite" or "eco-composite".

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.32 no.1
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• pp.60-64
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• 2006

Backgrounds: Though they are considered as reliable devices, titanium plates and screws have limitations due to some potential problems. To overcome these problems, researches on bioabsorbable materials for internal fixation have been continuing. Recently, there are many clinical trials to apply biodegradable internal fixation devices in oral and maxillofacial surgery. The purpose of this study was to evaluate the clinical results of application of bioabsorbable plates and screws in orthognathic surgery. Methods: Fifty-four patients with dentofacial deformity (17 male patients and 37 female patients) were selected in this study. The patients were treated by internal fixation using bioabsorbable plates and 2.4-mm, 2.0-mm pretapped screws (Biosorb FX, Bionix Implants, Inc., Finland). The patients were evaluated for complications during the follow-up period. Results: Five patients (9.3%) experienced complications. All complications in these cases were infection. No other complications related with physical or mechanical properties of bioabsorbable plates were found such as malunion or nonunion, fractures of plates and loosening of screws. All complications were minor and adequately managed with drainage and supportive care with antibiotics coverage. Conclusions: From the results, the use of these fixation systems in orthognathic surgery will provide a promising alternative titanium fixation in appropriate cases.

• Journal of Biosystems Engineering
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• v.30 no.5 s.112
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• pp.285-292
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• 2005

Extrusion process and physical properties of extrudates of pulp powder (TMP, thermomechanical pulp fibers) mixed with expanding additives was evaluated to develop biodegradable packaging materials. To find out the optimum condition, the status of extrusion process, coefficient of elastic and expansion ratio of extrudates were tested on the composites (wheat flour, soluble starch, polyvinyl alcohol), blending conditions of composites and moisture contents of extrudates. In case of material composition, wheat flour played a key role to keep extrusion process irrespective of the added amounts of soluble starch and polyvinyl alcohol. The coefficient of elastic of extrudates was increased and the expansion ratio was reduced as the added amounts of wheat flour increased. Also, the coefficient of elastic of extrudates was decreased as the moisture content of extrudates increased. The lowest coefficient of elastic was 439.55 kPa under the condition, of pulp powder mixed with $20\%$ of wheat flour based on pulp weight and $10\%$ of soluble starch based on wheat flour weight and controlled $20\%$(wb) of moisture content.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.40 no.1
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• pp.62-67
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• 2008

Biocomposite was fabricated with biodegradable polymer and natural fiber that has potential to be used as replacement for glass fiber reinforced polymer composite with the benefits of low cost, low density, acceptable specific strength, biodegradability, etc. Until now, mostly natural cellulosic fibers on land have been used as reinforcement for biocomposite. The present study focused on investigating the fabrication and the characterization of biocomposite reinforced with red algae fibers from the sea. The bleached red algae fiber (BRAF) showed very similar crystallinity to the wood cellulose. It has high stability against thermal degradation (maximum thermal decomposition temperature of 359.3$^{\circ}C$) and thermal expansion. Biocomposites reinforced with BRAF have been fabricated by a compression molding method and their mechanical and thermal properties have been studied. The storage modulus and the thermomechanical stability of PBS (polybuthylenesuccinate) matrix are markedly improved by reinforcing with the BRAF. These results indicate that red algae fiber can be used as an excellent reinforcement of biocomposites, which are sometimes called as "green-composites" or "eco-composites".

• Maxillofacial Plastic and Reconstructive Surgery
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• v.42
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• pp.34.1-34.7
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• 2020

Purpose: The purpose of this study was to evaluate the influence of biodegradable polycaprolactone membrane on new bone formation and the biodegradation of biphasic alloplastic bone substitutes using animal models. Materials and methods: In this study, bony defect was formed at the canine mandible of 8 mm in diameter, and the defects were filled with Osteon II. The experimental groups were covered with Osteoguide as barrier membrane, and the control groups were closed without membrane coverage. The proportion of new bone and residual bone graft material was measured histologically and histomorphometrically at postoperative 4 and 8 weeks. Results: At 4 weeks, the new bone proportion was similar between the groups. The proportion of remaining graft volume was 27.58 ± 6.26 and 20.01 ± 4.68% on control and experimental groups, respectively (P < 0.05). There was no significant difference between the two groups in new bone formation and the amount of residual bone graft material at 8 weeks. Conclusion: The biopolymer membrane contributes to early biodegradation of biphasic bone substitutes in the jaw defect but it does not affect the bone formation capacity of the bone graft.

• Science of Emotion and Sensibility
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• v.25 no.2
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• pp.55-70
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• 2022

In the 21^st century, the demand for eco-friendly leather, such as eco-leather and vegan leather, is steadily increasing. This study examines the influence of eco-friendliness on consumers' purchasing intentions and the possibility of eco-friendly changes in the fashion accessory market, which is dominated by leather material and leather substitutes. This study administered a questionnaire survey to 227 males and females between 20 and 60 years of age in Korea. With a 5-point Likert scale, data were collected on evaluation criteria when purchasing shoes and bags and purchasing intention of various leather substitute materials according to the democratic variables. The eco-friendliness attitude was divided into eco-consciousness and green behavior. As the eco-friendly attitude increased, most purchasing standards increased, but the purchasing criteria, such as trends, brands, and prices, did not correlate with the eco-friendly attitude. The eco-consciousness of a consumer had a high correlation with the design evaluation criteria, while the green behavior of the consumer aligned with durability and comfort criteria when purchasing a bag. There was a preference for recycled leather, vegetable leather, synthetic leather, and chemical leather, and the fabric type was ranked as natural fiber, biodegradable fiber, and synthetic fiber. Consumers with both green behavior and eco-consciousness are more likely to purchase biodegradable textiles and vegetable leather for the material of shoes and bags.

• Korean Chemical Engineering Research
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• v.61 no.4
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• pp.584-590
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• 2023

In this study, we focus on the recycling of cardboard waste and sugarcane bagasse (SCB) for the preparation of carboxymethyl cellulose (CMC) and its conversion into a biodegradable film. Sodium alginate (SA) was added to form a biodegradable composite film. SA was used to increase film permeability. Glycerol, which is a plasticizer, was used to increase the tensile strength (TS) and film expansion. To characterize the CMC, X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy were used. The addition of olive oil to the CMC-SA matrix highlighted its antimicrobial property against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). A slight decrease in tensile strength was observed with the addition of olive oil (OO), which improved the functional properties of the control films as well as lowered moisture content and water solubility. But considering all other factors, the composite films obtained from sugarcane bagasse and cardboard waste incorporated with olive oil are suitable for applications in the field of food packaging.

• Composites Research
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• v.26 no.5
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• pp.273-278
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• 2013

PLA/PP polymer blends in various ratios (PLA:PP = 9:1, 4:1, 3:1, and 1:1), and their composites (PLA:PP = 1:1) with sisal fiber (10, 15 and 20 wt%) were fabricated using MAPP as compatibilizer. The aim of the work was to reduce the cost of biodegradable composites as well as to improve the impact strength of PLA using PP, a relatively cheaper thermoplastic. The developed composites were characterized for their morphological and mechanical properties. The tensile strength and modulus of the blends were decreased with increasing PP content whereas the strain at break and impact strength are increased. The tensile strength, modulus and water absorption were increased for hybrid composites with increasing fiber content.

• Journal of the Korean Ceramic Society
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• v.45 no.10
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• pp.631-637
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• 2008

Self-standing mesoporous bioactive glass/poly($\varepsilon$-caprolactone) composite thin films with good molding capability, bioactivity, and biocompatibility in vitro, which may find potential applications in tissue engineering and drug storage, were prepared using a combination of the sol-gel, polymer templating, and water casting method. The thickness of self-standing films was affected by the difference of dielectric constant between distilled water and organic solvent.

• BMB Reports
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• v.46 no.5
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• pp.244-251
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• 2013

Lignocellulosic materials are commonly used in bio-$H_2$ production for the sustainable energy resource development as they are abundant, cheap, renewable and highly biodegradable. In the process of the bio-$H_2$ production, the pretreated lignocellulosic materials are firstly converted to monosaccharides by enzymolysis and then to $H_2$ by fermentation. Since the structures of lignocellulosic materials are rather complex, the hydrolysates vary with the used materials. Even using the same lignocellulosic materials, the hydrolysates also change with different pretreatment methods. It has been shown that the appropriate hydrolysate compositions can dramatically improve the biological activities and bio-$H_2$ production performances. Over the past decades, hydrolysis with respect to different lignocellulosic materials and pretreatments has been widely investigated. Besides, effects of the hydrolysates on the biohydrogen yields have also been examined. In this review, recent studies on hydrolysis as well as their effects on the biohydrogen production performance are summarized.