• Journal of Korean Ophthalmic Optics Society
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• v.17 no.1
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• pp.1-10
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• 2012

Purpose: Cellulose acetate (CA) was blended with polyethyleneglycol (PEG) having different molecular weight at various mixing conditions to enhance melt-processibility of CA, which might prevent the harmful effect resulted from the introduction of phthalic plasticizer. Methods: To establish optimal plasticizing conditions, CA/PEG blends were examined under various plasticizing conditions: PEG concentration, molecular weight of PEG, and plasticzing temperature. Mechanical properties of the CA/PEG blends, as well as migration and exudation of the PEG, were performed in order to evaluate the efficiency of plasticization. Results: Compared to industrial CA resin plasticized by diethyl phthalate, CA/PEG blends exhibited similar thermal plasticization. It was established that the optimum condition was to blend 30~40 phr PEG with molecular weight 400 at $175{\sim}180^{\circ}C$. CA/PEG blend showed superior glassness, PEG stability, and mechanical properties. Conclusions: CA/PEG blends would be a eco-friendly glasses frame to substitute traditional CA glasses frame prepared phthalate plasticizers.

• Membrane Journal
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• v.17 no.4
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• pp.277-286
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• 2007

The technology of seawater desalination has been received much attentions to solve the problem of water shortage through all over the world. In this study, it attempts to confirm the use-possibility of cellulose triacetate (CTA) for preparation of reverse osmosis membranes which have been highlighted as high efficiency and low energy consumption process for seawater desalination. The effects of casting dope parameters like an acetyl content, solvent, additives on the membrane performance were investigated. It was possible to produce the membranes which have high water flow rate and salt rejection with the increase of acetyl content and dioxane content among various dioxane/acetone ratios. Acetic acid and maleic acid were preferred for additives to produce high performance membranes. It was verified that $HOLLOSEP^{(R)}$ module which is commercialized CTA membrane by TOYOBO Co. can produce stable water production and high-quality water for long-term operation in the practice plants without any chemical treatments.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.05a
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• pp.934-937
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• 2007

This study focused on investigating the effect of aligned cellulose fibers to the performance of EAPap actuator. The performance of EAPap is dependant on the material direction of cellulose film. Electrospinning was used to improve material directionality of EAPap. DMAc cellulose solution which cotton pulp was resolved in DMAc solvent was used for electrospinning cellulose film. To increase directionality of nano fibers, the Electrospun film was stretched by 10 % strain during drying process. Induced in-plane strain of Electrospun EAPap was proportional to the applied voltage and larger than that of spincast EAPap. It is concluded that the performance of EAPap was improved by aligning cellulose fibers.

• Korean Journal of Agricultural Science
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• v.46 no.3
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• pp.549-557
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• 2019

Staphylococcal enterotoxin is a very common cause of food poisoning. Conventional detection methods for the toxin including enzyme-linked immunosorbent assays (ELISAs), chemiluminescence (ECL), and polymerase chain reaction (PCR) assays require a lot of time, efforts, and expert technicians. Lateral flow strip kits have shown great potential for the rapid detection of foodborne pathogens. The lateral flow strip kit is widely used in clinical settings because it is easy to use, fast, and cost effective. A typical lateral flow strip kit uses colloidal gold to generate a visual signal. However, the lateral flow strip kit based on colloidal gold has limited sensitivity to fulfill food safety regulation requirements. This study was performed to develop a rapid test kit for pathogenic staphylococcal enterotoxin B (SEB) in food samples. The rapid detection kit was fabricated based on a nitrocellulose lateral-flow strip. Cellulose nano beads and SEB antibodies were used as the tag and receptor, respectively, to improve the detection performance. Manually spotted SEB antibody and anti-rabbit antibody on the surface of the nitrocellulose membrane were used as test and control spots, respectively. The feasibility of the rapid test kit to detect SEB in samples was evaluated. The sensitivity of the kit was 10 ng/mL SEB spiked in PBS. Additionally, the rapid test kit could detect 1 ng/mL of SEB in chicken meat extract.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.11a
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• pp.905-906
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• 2010

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.263-264
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• 2018

Recently, interest in making nanocomposite materials for construction utilizing the excellent physical properties of nano materials is increasing. In this study, basic properties of mortar were evaluated by the dispersion condition of cellulose nano-crystals (CNCs) extracted from nanocellulose and the feasibility of the study was examined. As a result, it was confirmed that the flexural strength and the compressive strength were increased by increasing the dispersion time of the CNCs and by using the ultrasonic dispersing device and the magnetic stirrer together.

• Polymer(Korea)
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• v.37 no.5
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• pp.613-617
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• 2013

The effects of nano size kenaf cellulose fiber on mechanical property of polypropylene (PP) composite were investigated. The addition of nano-kenaf in place of natural kenaf showed higher tensile strength, flexural strength, impact strength, and heat deflection temperature compared to the natural kenaf filled PP composite, while it shows lower melt flow index, elongation%, and flexural modulus. These seemed to be due to the increased surface area of nano-kenaf fiber contacting PP matrix and reduced impurities such as volatile extractives on the fiber surface.

• Applied Chemistry for Engineering
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• v.32 no.1
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• pp.110-116
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• 2021

In this work, the surface of hydrophilic cellulose nanofibrils (CNFs) was modified precisely by varying amounts of cetyltrimethylammonium bromide (CTAB) to produce CNF-based particle surfactants. We found that a critical CTAB density was required to generate amphiphilic CTAB-grafted CNF (CNF-CTAB). Compared to pristine CNF, CNF-CTAB was highly efficient at stabilizing oil-in-water Pickering emulsions. To evaluate their effectiveness as particle surfactants, the surface coverage of oil-in-water emulsion droplets was determined by changing the CNF-CTAB concentration in the aqueous phase. Furthermore, styrene-in-water stabilized by CNF-CTAB surfactants was thermally polymerized to produce CNF-stabilized polystyrene (PS) particles, offering a great potential for various applications including pharmaceuticals, cosmetics, and petrochemicals.

• Textile Coloration and Finishing
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• v.24 no.1
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• pp.62-68
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• 2012

Cellulose was electrospun over water collector and the cellulose solution was prepared using N-methyl-morpholine N-oxide/water(nNMMO/$H_2O$). The morphology of electrospun cellulose was investigated by scanning electron microscopy (SEM). SEM images showed that the fiber formation depended on processing parameters such as solution concentration, applied electric field strength, solution feeding rate and temperature of water in coagulation bath. High concentration, low temperature of water bath, and low feeding rate were more favorable to obtain fiber morphology. All the variables affected on the fluidity of the cellulose solution and diffusion of NMMO. Low fluidity and fast diffuision of NMMO was critical for obtaining fiber morphology.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2010.03a
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• pp.113-114
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• 2010