• 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.

• Textile Coloration and Finishing
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• v.16 no.5
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• pp.28-34
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• 2004

The polarizing film application exploits the unique physicochemical properties between PVA(Poly vinyl alcohol) film and CTA(Cellulose triacetate) film. However, hardly any research was aimed at improving the adhesion characteristics of the CTA film by radio frequency(RF) plasma treatment at argon(Ar) gaseous state. In this report, we deal with surface treatment technology for protective CTA film developed specifically for high adhesion applications. After Ar plasma, surface of the films is analyzed by atomic force microscopy(AFM), roughness parameter and peel strength. Furthermore, the wetting properties of the CTA film were studied by contact angle analysis. Results obtained for CTA films treated with a glow discharge showed that this technique is sensitive to newly created physical functions. The roughness and peel strength value increased with an increase in treatment time for initial treatment, but showed decreasing trend for continuous treatment time. The result of contact angle measurement refer that the hydrophilicity of surface was increased. AFM studies indicated that no considerable change of surface morphology occurred up to 3 minutes of treatment time, but a considerable uneven of surface structure resulted from treating time after 5 minutes.

• Textile Coloration and Finishing
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• v.3 no.4
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• pp.17-21
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• 1991

A rigid polymer, cellulose triacetate (CTA) dissolved in a combination of trifluoroacetic acid (TFA) and methylene chloride (MC) solution are liguid crystalline above a certain concentration. A flexible polymer, polyethylene terephthalate (PET) also dissolves in TFA/MC, but does not form liguid crystal phase. Ternary solutions, CTA/PET/TFA-MC which CTA and PET were mixed in a same solvent TFA/MC (6/4 : v/v) showed phase separation and mesophase formation.

• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1391-1396
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• 2013

The photocontrolled reduction of silver nitrate to silver (Ag) nanoparticles on honeycomb-patterned poly(N-vinylcarbazole) (PVK)-cellulose triacetate (CTA) composite thin films was studied. The composites were prepared via the oxidative polymerization of N-vinylcarbazole with ferric chloride using different CTA concentrations. A honeycomb-patterned film was fabricated by casting the composite solution under humid conditions. Ag particles with a homogeneous distribution were produced by the composite film in a moderate CTA concentration, whereas aggregated Ag was obtained from the pure PVK film.

• Textile Coloration and Finishing
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• v.4 no.1
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• pp.26-29
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• 1992

Ternary solutions that cellulose triacetate (CTA) and polyethylene terephthate (PET) were mixed in a solvent trifiuoroacetic acid (TFA)/methylene chloride (MC) (6/4 : v/v) showed phase separation and mesophase formation. The ternary systems which were mesomorphic were spun into a methanol both and relatively strong cellulosic fillaments were successfully produced. Analysis showed that CTA/PET fibers have fibrillar structure and high orientation parallel to the fiber axis. These fibers proved to be molecular composite and have relatively high strength and modulus as spun.

• Textile Coloration and Finishing
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• v.6 no.1
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• pp.44-48
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• 1994

Cellulose triacetate(CTA) liquid crystal solutions obtained via dissolution of CTA in solvent mixture of triflucroacetic acid and methylene chloride were spun and saponified in various chemicals. Among chemicals, methanol/sodium hydroxide mixture endowed highest tenacity as well as modulus to regenerated cellulosic fiber and the fiber thereof showed Cell I or Cell IV morphology, or mixed morphology of Cell I and IV.

• Journal of the Korean Applied Science and Technology
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• v.26 no.4
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• pp.428-433
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• 2009

Cellulose triacetate (CTA) was prepared from cotton linter and pulps which contain various contents of $\alpha$-cellulose. CTA which contains 2.8 of degree of substitution (DS) and 222 of degree of polymerization (DP) was obtained from V-81 pulp under the heterogeneous system. The DS was measured by the titration method, and the DP was obtained by measurement of viscosity. FT-IR spectometer (FT-IR 6300, JASCO) was used to analyze the chemical structure of raw materials and cellulose triacetate, and X-ray diffractometer (X-pert MPD PW3040, Philips) was used to confirm the crystal structure and to calculate the relative crystallinity index (RCI). As $\alpha$-cellulose content in pulp increased, the acetylation yield increased. Besides with a kind of pulp, it contains insoluble residue which was mainly formed due to the formation of glucomannan triacetate and xylan diacetate during the esterification.

• Membrane Journal
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• v.21 no.1
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• pp.98-105
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• 2011

Cellulose triacetate (CTA) polymer among cellulose esters were used for preparing hollow fiber membranes by phase separation method to investigate the gas permeation properties. To endow gas separation properties, 1,4-dioxane and LiCl were used as additives in the polymer dope solution. The spinning conditions including spinning temperature were controlled to form an active skin layer on the hollow fiber surface. Scanning electron microscopy was used to examine morphology of surface and cross section of the prepared CTA hollow fibers. The gas permeation performance of CTA hollow fiber membranes showed $P_{CO2}$ = 17 GPU and ${\alpha}_{CO2/N2}$ = 48.

• Bulletin of the Korean Chemical Society
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• v.31 no.8
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• pp.2207-2210
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• 2010

This paper describes the preparation and study of thermally stimulated discharge conductivity (TSDC) study of cellulose triacetate (CTA) - multiwalled carbon nanotubes (MWNTs) film thermoelectrets. TSDC has been carried out in the temperature range 308 - 503 K and at four different polarizing fields. The conductivity of the polymer blends increased with increase in temperature showing a semi-conducting behavior. The apparent activation energy also showed a pronounced effect with the increase in the content of MWNTs.

• Membrane Journal
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• v.20 no.3
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• pp.222-227
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• 2010

The purpose of this study is to prepare forward osmosis (FO) membranes using a variety of cellulose-based polymers and to evaluate the performance of difference depending on each of the polymers and additives. Forward osmosis membranes based on cellulose acetate (CA) and cellulose triacetate (CTA) were prepared through phase inversion. The performance of FO membranes developed, such as flux and salt rejection, was compared under the osmotically- and pressure-driven conditions. In CA FO membranes, the execution time of solvent evaporation and membrane annealing induced the change in membrane performance. But the performance of CTA FO membrane was improved by using additives rather than annealing. Moreover, the flux of CTA FO membrane was $4.46\;L/m^2hr$ but that of CA/CTA FO membrane was $8.89\;L/m^2hr$ in FO mode. The CTA FO membrane with blending CA was more efficient to increase FO permeate flow rather than using a single polymer membrane.