• Applied Chemistry for Engineering
• /
• v.16 no.1
• /
• pp.101-106
• /
• 2005

Photocurable modified 6 functional polyacrylate(PA-1) were prepared from dipentaerythritol derivatives (DPET) and acrylic acid, and 12 functional polymethacrylate(PA-2) were prepared from dipentaerythritol derivatives (DPET), trimellitic anhydride, and glycidyl methacrylate. And physical properties of photocurable modified poly(meth)acrylate were increased with increasing functionality of (meth)acrylate. Thermal stability of UV cured film obtained by using TGA was shifted to higher temperature as the increasing of functionality. Hardness, abrasion resistance and tensile strength of UV cured film were increased with increasing functionality of (meth)acrylate. Values of yellow index were increased with increasing functionality of (meth)acrylate.

• Journal of Surface Science and Engineering
• /
• v.28 no.1
• /
• pp.34-45
• /
• 1995

An amphiphilic nitroxide radical(2,2'6,6'-tetramethyl-4-octadecyioxy-1-piperidinyloxyl, TEMOPO) or mixture of TEMOPO and arachidic acid(Icosanoic acid, AA), was spread on water surface by the Langmuir-Blodgett(LB) method and surface pressure-area curve was measured. Such monolayer films of TEMOPO were transferred onto surfaces of photo transferable tin oxide electrodes(PTTO) by the LB method under various surface pressure with the transfer ratio of larger than 0.95 at the surface pressure higher than 15mN/m. The electrochemical effect of functional nitroxy radical monolayer onto semi-conductive electrode to electrolyte have been investigated by using LB method. Cyclic voltammetry technique was used for the electrochemical behavior measurement of TEMOPO monolayer onto the PTTO in 0.18 mo1/$dm^3$ $H_2SO_4$ solutions. The shape of voltammograms was found to change from one electrode to another. The amount of charge for the oxidation and the re-reduction of the cation to TEMOPO were evaluated from graphical integration. The amounts of charge were always smaller than those predicted from the $\pi$-$\sigma$ curves though the transfer ratio was unity. The poor reproducibility of the cyclic voltammograms was improved by the mixing with AA. Structure and arrangement of monomolecular layer on water surface and electrode were studied. Characteristics of monolayer film applied for the mediation reaction was also discussed by electrochemical method.

• Journal of Environmental Health Sciences
• /
• v.47 no.1
• /
• pp.55-63
• /
• 2021

Objectives: Cefotaxime is an antibiotic used to treat several bacterial infections. Specifically, it is used to treat pelvic inflammatory disease, meningitis, pneumonia, urinary tract infections, and sepsis. It is given by injection into either a vein or muscle. Antibacterial polymers prepared by chemical bonding and simple blending of antibacterials into polymers has attracted much interest because of their long-lasting antibacterial activity. This study attempted to review the possibility of hydrogel films as functional antibacterial materials by antimicrobial activity. Methods: In this study, CTX-PAA was synthesized by the chemical reaction of polyacrylic acid with cefotaxime by N,N'-Dicyclohexylcarbodiimide (DCC) method. Synthetic antibacterial hydrogel films were then prepared with PVA and CTX-PAA for functional application. Results: The increase in the cefotaxime content of the hydrogel films showed a similar decrease in tensile strength and elongation. The values of films impregnated with chemically bonded cefotaxime showed no significant difference. Antibacterial susceptibility was determined against Streptococcus pneumoniae and Escherichia coli using a standardized disc test. Conclusion: The synthetic antibacterial hydrogel films exhibited broad susceptibility against Streptococcus pneumoniae and Escherichia coli. Notably, the antibacterial effect of antibacterial hydrogel films against Grampositive (Streptococcus pneumoniae) was superior to that against Gram-negative (Escherichia coli).

• Korean Journal of Food Science and Technology
• /
• v.24 no.6
• /
• pp.574-580
• /
• 1992

Chitin was isolated from the residue of enzymatically hydrolyzed crab, Portunus trituberculatus, and further deacetylated by alkaline boiling to make chitosan. The physical properties of chitosan solution and its film forming properties were examined. The functional characteristics of chitosan film were compared to those of cellophane, polyvinyl chloride (PVC) and polyethylene (PE) films. The proximate chemical composition of chitin obtained from crab residue was 6.95% nitrogen, 0.3% crude ash and 4.57% moisture and the product yield was 12.8% based on a dry material basis. The degree of deacetylation of chitosan was $79{\sim}92%$ and $70{\sim}86%$ as determined by IR spectroscopy, and $70{\sim}86%$ as determined by colloid titration method each respectively. The chitosan at 1% acetic acid solution showed distinct pseudoplastic flow behavior. The flow behavior index and consistency index were 0.8886, 0.2084 $MPa{\cdot}s^n$ for 0.4% solution and 0.8498, 0.6190 $MPa{\cdot}s^n$ for 0.8% solution, respectively. The chitosan film had the highest tensile strength $(888 kg/cm^2)$ and water permeability $(100\;g/m^2{\cdot}24\;hrs)$ among the tested films, but relatively low elongation property (49%). It showed the similar tear strength (90kg/cm) and light permeability (87.7%) to other films tested in spite of the relatively high haze value (12.5%). As the thickness of chitosan film increased from 0.025 to 0.050 mm, the tensile strength of film decreased distictively, and the degree of elongation, tear strength, and water permeability of film also decreased slightly. Whereas the light permeability of film did not change and the haziness of film slightly increased by the increase of film thickness.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.12 no.12
• /
• pp.5477-5485
• /
• 2011

This study comparatively analyzed the instrumentation and the voicing structure, which were shown in the film music titled "Star Wars-Main Title" by John Williams(1932~), with analytical technique that the writer mapped out, and aimed to discover the progression principle in orchestration based on the results. Also, it applied a functional part-division method that was classified and distributed into 3 functional parts according to auditory cognitive level as for each of functional elements such as the musical element. And, it made it pattern for the vertical structure and the voicing structure in musical instruments, which were distributed to each functional part based on this, and comparatively analyzed the standard point in a change which were shown according to progression of music, namely, the operating technique. As for the results of this study, first, each theme has specific instrumentation pattern. Unity was emphasized by consistently organizing those things in exposition, reprise, and recapitulation of each theme. To reinforce diversity, an attempt was made such as adding and reducing auxiliary instruments in the middle part and the rear part. Second, even in a change of instrumentation pattern by passage in accordance with a change in theme amid each part, the same instrumental group was organized in the middle part, thereby having maintained unity. Third, to strengthen diversity by clause, which is forming each theme, a continuous change in voicing pattern was created by adding or omitting a part. Fourth, the voicing concentration was maintained the structure of "thinness-thickness" in the whole musical piece. However, in part 2 that is repeated theme 3, diversity was pursued with a unique change of "thickness-thickness." Fifth, in part 4 that is indicated theme 4, the other diversity was intensified with the inverted range in the front part and the middle part. Accordingly, based on the conclusions that were indicated in this work, it is desired to be conducive to understanding the horizontal consideration and the progression principle of orchestration.

• Polymer(Korea)
• /
• v.37 no.3
• /
• pp.316-322
• /
• 2013

In this study, poly(ethylene terephthalate) (PET) was treated with fluorination and ultrasonic washing treatment for hydrophilic modification of PET film. We measured the change of surface modified PET film surface characteristics using contact angle, surface free energy, FE-SEM, AFM and XPS. After direct fluorination and ultrasonic washing treatment, the water contact angle was measured to be $10.81^{\circ}$, 85% reduction compared to the untreated PET film. Total surface free energy has been measured to be $42.25mNm^{-1}$, 650% increase compared to the untreated PET film. Also RMS roughness has been measured to be 1.965 nm, 348% increase compared to the untreated PET film. Hydrophilic functional group C-OH bond concentration has increased approximately 3 times. These results are attributed to the hydrophilic functional group and cavitation due to chemical etching. From this result, it was suggested that the fluorination-ultrasonic washing treatment method could be useful to make PET film surface hydrophilic.

• Food Science and Preservation
• /
• v.13 no.2
• /
• pp.125-130
• /
• 2006

In order to study the storage stability of winter date (Zizyphus jujuba Miller) with functional MA film storage, linear low density polyethylene $(LLDPE,\;30{\mu}m\;and\;60{\mu}m)$ film packaging and non-packaging were compared $30{\mu}m$ LLDPE packaging, $60{\mu}m$ LLDPE packaging and non-packaging samples were stored at $0^{\circ}C,\;8^{\circ}C$ (low temperature) and $25^{\circ}C$(room temperature) for 10 weeks. Weight loss of $30{\mu}m$ LLDPE packaging, $60{\mu}m$ LLDPE packaging and non-packaging in room temperature were decreased by 3.6% 0.4% and 36.1% respectively. Titratable acidity showed the trend of similarity in all treatment during the storage conditions, and especially LLDPE film packaging showed higher than non-packaging in the last storage. Soluble solids showed an increase in non-packaging, a decrease in LDPE film packaging highly. Vitamin C content showed the trend of decrease in all treatments, but non-packed jujubes sustained higher than LLDPE film packaging.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.33 no.3
• /
• pp.97-103
• /
• 2023

Barrier films for transparent packaging materials with excellent moisture barrier properties are prepared, utilizing a nanoclay dispersion coating layer formed after a pretreatment process of plasma activation surface treatment process under vacuum at room temperature. Attention is paid on optimizing the coupling additive through the appropriate crosslinking process and optimal dispersion process of the coating process to enhance adhesion. Analysis of the functional coating thin film shows that the water vapor transmission rate is less than 10 g/m²/24 hrs (ASTM F-1249) and the oxygen transmission rate is less than 30 cc/m²/24 hrs (ASTM D3985). It is shown that water barrier properties of coating thin film prepared in this study are greater than conventional untreated films by 10 times or more. The thickness of the transparent gas barrier film is within 0.1 mm, and the transparent gas barrier complex is implemented in two layers. In the study of PET thin film interface characteristics, FT-IR experimental analysis shows the reaction activity was optimized at RDS 1.125 %.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.25 no.8
• /
• pp.584-592
• /
• 2012

Room temperature powder spray in vacuum process, so called Aerosol deposition (AD) is a room temperature (RT) process to fabricate thick and dense ceramic films, based on collision of solid ceramic particles. This technique can provide crack-free dense thin and thick films with thicknesses ranging from sub micrometer to several hundred micrometers with very fast deposition rates at RT. In addition, this technique is using solid particles to form the ceramic films at RT, thus there is few limitation of the substrate and easy to control the compositions of the films. In this article, we review the progress made in synthesis of piezoelectric thin/thick films, multi-layer structures, NTC thermistor thin/thick films, oxide electrode thin films for actuators or sensor applications by AD at Korea Institute of Materials Science (KIMS) during the last 4 years.

• The Transactions of the Korean Institute of Electrical Engineers P
• /
• v.64 no.3
• /
• pp.182-186
• /
• 2015

We investigated that effects of annealing ambient on the characteristics of functional nano thin film synthesized on glass substrate. The functional nano thin films were annealed by using rapid thermal annealing (RTA) equipment in vacuum, oxygen and nitrogen ambient, respectively. The hardness of the functional nano thin films were measured by a standard hardness testing method (ASTM D3363) such as a H-9H, F, HB and B-6B pencil (Mitsubishi, Japan). Also, the adhesion of the functional nano thin films were measured by a standard adhesion testing method (ASTM D3359) using scotch tape (3M, Korea). The contact angle of the functional nano thin films was measured by a contact angle analyzer (Phoenix 300 Touch, S.E.O.). The optical property of functional nano thin films was measured via UV-visible spectroscopy (S-3100, Scinco).