• Bulletin of the Korean Chemical Society
• /
• 제32권9호
• /
• pp.3361-3366
• /
• 2011

New Y-type polyester (3) containing nitrophenylazoresorcinoxy groups as NLO chromophores, which are components of the polymer backbone, was prepared and characterized. Polyester 3 is soluble in common organic solvents such as N,N-dimethylformamide and acetone. It shows a thermal stability up to $240^{\circ}C$ in thermogravimetric analysis with glass-transition temperature ($T_g$) obtained from differential scanning calorimetry near $116^{\circ}C$. The second harmonic generation (SHG) coefficient ($d_{33}$) of poled polymer film at the 1064 nm fundamental wavelength is around $4.63{\times}10^{-9}$ esu. The dipole alignment exhibits a thermal stability even at $4^{\circ}C$ higher than $T_g$, and there is no SHG decay below $120^{\circ}C$ due to the partial main-chain character of polymer structure, which is acceptable for NLO device applications.

• 한국환경보건학회지
• /
• 제23권3호
• /
• pp.85-90
• /
• 1997

The objective of this study was to investigate biodegradation of TPA(terephthalic acid) and EG (ethylene glycol), treatment efficiency of polyester weight loss wastewater and microbial characteristics by aerated submerged biolfilm(ASB) p.rocess. In a batch reactor, pH increased from 7.0 to 8. 5 in the biodegradation of TPA. Whereas, in case of EG, decreased from 7.0 to 5.2. COD concentration rapidly decreased within 24hr in the biodegradation of TPA and EG. COD removal velocity constant(k) were 0.065-0.088 hr$^{-1}$. The biodegradation velocity of TPA was 1.4 times faster than that of EG. The ratio of suspended biomass to the total biomass in the reactor was 18.3-33.3%, increased as a high ratio of EG content. Biofilm thickness, biofilm dry density and attached biomass were 346-432 $\mu$m, 41.8-61.9 mg/cm$^3$, 1.45-2.67 mg/cm$^2$, respectively. There values increased as a high ratio of TPA content. In the hydraulic retention time of 36 hr, organic loading rate of 4 kgCOD/m$^3\cdot$ day and packing ratio of 70%, the effluent concentrations of TCOD, SCOD in a continuous flow reator were 1,388 mg/l, 147 mg/l and removal efficiencies were 77%, 97.6%, respectively.

• 한국의류학회지
• /
• 제29권1호
• /
• pp.149-156
• /
• 2005

The purpose of this study was to produce the high quality of electromagnetic wave shielding fabrics. In this study, we have produced polyester fabrics by electroless Ag plating. The untreated polyester was etched with $4\%$ NaOH solution added accelerant(Benzyl Dimethyl Dodecyl Ammonium Chloride) then it was catalyzed by $SnCl_2$ solution and activated by $PdCl_2$ solution. Electroless Ag plating was carried out by changing conditions such as temperature. time, weight loss rate of polyester and kind of reducing agents. The electromagnetic wave shielding effectiveness of polyester fabric by electroless Ag plating was measured by RF Impedance Analyzer and element of electromagnetic wave shielding substance was measured using Electron probe micro analyzer. The results were as follows; The plating bath using potassium sodium tartrate by reducing agent was excellent electromagnetic wave shielding effectiveness. Element of electromagnetic wave shielding substance was silver. Electromagnetic wave shielding effectiveness was shown over 64dB at the temperature of $40^{\circ}C$, treating time 30min., weight loss rate $20\%$.

• 한국응용과학기술학회지
• /
• 제26권3호
• /
• pp.317-327
• /
• 2009

In this study DMT(Dimethylterephthalate), NDC(Dimethyl-2, 6-Naphthalene Dicarboxylate) were used to synthesize polyester polyol which shows enhanced storage stability, improved flame retardancy, and good compressive strength. If DMT and NDC react respectively with DEG(Diethylene Glycol) which is kind of linear diol, the obtained polyester polyols tend to crystallize easily after the reaction. In case of DMT, PA(Phthalic Anhydride) which has asymmetric structure was introduced to retard the crystallization. In case of NDC, DPG(Dipropylene Glycol) which has an methyl side chain was introduced to prevent the crystallization. It was found that to introduce DPG was much more effective method to prevent the crystallization than PA. NDC and DMT were reacted together with DPG for various compositions of NDC:DMT(8:2, 6:4, 4:6 mol ratio). The obtained NDC-DMT-DPG based polyester polyol showed improved flame retardancy, and good compressive strength with increasing the content of NDC.

• 한국의류산업학회지
• /
• 제7권1호
• /
• pp.111-114
• /
• 2005

In this the study, polyester/cotton(P/C) blended fabrics with fine denier were developed to get the light weight compared with the traditional P/C blended fabrics. Moreover, the width of the fabrics was extended by the tenter during the final heat treatment to get the lower fabric density and lighter weight. Then, the physical properties of these fabrics were analysed. The results were as the follows: The developed fabrics had 22.6-31.6% lighter weight than the traditional fabrics with the same fabric width. The weight of fabric decreased drastically with the fabrics width down to 67.1 $g/m^2$. The fabric density for the warp direction decreased with the fabric width. The tenacity and the elongation of the developed fabrics was little lower than that of the traditional fabrics. The air permeability of the developed fabrics increased with that of the traditional fabrics. The stretch rate of the developed fabrics decreased with increasing the fabric width. Residual stretch rate of the developed fabrics was more stable than that of the traditional fabrics. Residual stretch rate of the developed fabrics increased with the fabric width, but the highest value was less than 5% which is quit stable.

• 한국재료학회지
• /
• 제2권2호
• /
• pp.133-142
• /
• 1992

E-glass/Polyester 적층복합재료의 인공해수중에서의 인장특성을 알아보기 위해 PH를 각각 6.0, 8.2, 10.0으로 조절한 가운데 저 변형율 인장시험($1{\times}10^{-4}~1{\times}10^{-7}sec^{-1}$)을 행하였다. 대기와 인공해수중에서 인장하중을 받은 시험된 복합재료는 strain rate가 감소할수록 인장특성이 저하되며 $1{\times}10^{-7}sec^{-1}$의 strain rate에서 약간의 강성저하가 관찰되었다. 한편 인공해수중의 인장특성은 PH값에 따라 약간의 변화를 보였다.

• 한국염색가공학회지
• /
• 제23권2호
• /
• pp.140-145
• /
• 2011

The effects of nonionic surfactant solutions of 0.1g/dL on detergency and liquid wetting/retention properties of soiled polyester/cotton(65/35) cloth were studied. Soiled polyester/cotton(65/35) cloth (EMPA 104) and 10 different nonionic surfactants (Span 20, Tween 20, 40, 60, 80, 21, 61, 81, 65, 85) were used in the study. The water retention and liquid retention capacity values of soiled cloth were decreased compared with those of unsoiled cloth. The wetting and water retention of soiled cloth improved with addition of surfactants, whereas water retention ratio(W/H) values didnot change markedly. Generally surfactants with low surface tension and high HLB (Hydrophile-lipophile balance) were more effective in improving the wetting/retention properties of soiled cloth. Nonionic surfactants having high ethylene oxide contents of 20 moles; i.e., Tween 20, 40, 60 & 80, showed better detergency than low ethylene oxide contents of 4 moles; i.e., Tween 21, 61 & 81. As HLB values of surfactants and $cos{\theta}$ of the soiled cloth increase, the detergency values of soiled cloth increased.

• 한국의류학회지
• /
• 제28권1호
• /
• pp.131-142
• /
• 2004

When the cotton/polyester fiber mixed fabrics were treated with ferrous sulfate and oxalic acid for burn out finishing, it was examined how the effects of process conditions as concentration of burn out agents, temperature, time and pressure act onto the properties of polyester ground fabrics. The results are as follows. The effect of burn out finishing by pressure was greated in 3 kgf/$\textrm{cm}^2$. The properties as white index and tensile strength of polyester ground fabrics were decreased according as processing concentration, temperature time increases. The shrinkage was increased according as processing concentration, temperature time increases. The optimum condition of burn out agents to ferrous sulfate was 30% concentration, 150$^{\circ}C$, 1 min, 3 kgf/$\textrm{cm}^2$ and to oxalic acid was 10% concentration, 110$^{\circ}C$, 1min, 3 kgf/$\textrm{cm}^2$. And the optimum of ferrous sulfate and oxalic acid used in combination was 10% ferrous sulfate and 7% oxalic acid, 110$^{\circ}C$, 1 min., 3 kgf/$\textrm{cm}^2$.

• 한국의류학회지
• /
• 제20권2호
• /
• pp.390-397
• /
• 1996

The effects of the mixture of surfactants on the removal of triolein applied to cotton and polyester fabrics were studied. The sunactants which were usually formulated to the Iriundry detergents, such as sodium dodecyl sulfonate (LAS), sodium lauryl sulfate (AS), $\alpha$-olefin sulfonate (AOS, C=14), sodium laurethoxy sulfate (AES, EO=3) and lauryl ethoxylate (AE, EO=7) were used. Washing was done at 40'C, 60"C, 80'c and the surfactant concentration was 0.05%. Backscattered electron imaging was made to study the location of triolein in the yarns. Triolein was removed easily from polyester than cotton fabrics.01eic acid added triolein wa9 removed greater than triolein only, except in AE solutions. In AE solutions, the removal of triolein was increased as the tremperature went higher and the increasing rate of the removal of triolein only was greater than that of oleic acid added triolein. In the result, more triolein was removed from triolein only than from oleic acid added triolein at 80t When the other surfactant was added to LAS, AES was the best to cotton fabrics, AOS was to polyester fabrics. Triolein was located in the lumen and grooves of the fibers and the deeper interfiber spaces. Triolein did not make thin film arround the cotton fiber in the surface, but polyester fibers. These are the main reason why the removal of triolein was difficult from cotton fabrics.rics.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2007년도 춘계학술논문 발표대회
• /
• pp.43-46
• /
• 2007

This study dealt with the influence of the replacement ratio of rapidly-chilled steel slag on fluidity and compressive strength of unsaturated polyester polymer concretes. The rapidly-chilled steel slag used in this study, a by-product which is produced by refining pig iron during the manufacture of steel, was controled by a air-jet method which rapidly cools substance melted at a high temperature. Experimental results show that fluidity and compressive strength of unsaturated polyester polymer concretes increase with increasing replacement ratio of rapidly-chilled steel slag. Use of rapidly-chilled steel slag was found to be effective for improving fluidity and compressive strength of rapidly-chilled steel slag.