• Polymer(Korea)
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• v.38 no.4
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• pp.425-433
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• 2014

In this study, microstructure and gel content (C-C) of polybutadiene rubber (PBR) were investigated using various techniques including ASTM D 3616, attenuated total reflectance Fourier transform infrared spectrometry (ATR FTIR), differential scanning calorimetry (DSC) and nuclear magnetic resonance spectroscopy (NMR). The ATR FTIR spectra of the samples were investigated to determine the cis, trans, 1, 2-vinyl and the C-C gel content in PBR. The absorbance ratios of specific peaks in different grades of PBR were correlated with the C-C gel content measured by the ATR FTIR techniques. Physico-mechanical and rheological properties of rubber compounds based on BR with various amounts of gel were determined. The results showed that there is an acceptable correlation between these properties and the C-C gel content of PBR.

• The Korean Journal of Food And Nutrition
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• v.16 no.2
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• pp.105-110
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• 2003

The effect of varietal differences of rice starches by amylose content and gel consistency on the retrogradation behavior was studied. The gel consistency test, which is designed to detect differences in the texture of cooked rice of varieties that have a similar amylose content, had been turned out to be useful in this study. Both Suwon 232 and San Li Cun had higher amylose content, but were greatly different in gel consistency values. The results showed that setback viscosity of rice flour measured in a Brabender amylograph was significantly affected by amylose content as well as gel consistency. Increase in the rigidity modulus (E) of rice starch gels during storage determined by using Texture analyzer indicated that amylose content was an important factor in terms of hardness development The study of Avrami kinetics of retrogradation showed that time constant of rice starch gels was influenced by amylose content, but not by gel consistency.

• Korean Journal of Food Science and Technology
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• v.28 no.6
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• pp.1052-1058
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• 1996

The effect of varietal differences of rice starches by amylose content and gel consistency on the retrogradation behavior was studied. Setback viscosity of rice flour measured in a Brabender amylograph was significantly affected by amylose content as well as gel consistency. Increase in the rigidity modulus (E) of rice starch gels during storage determined by using texture analyzer indicated that amylose content was an important factor in terms of hardness increase. Kinetics of retrogradation showed that time constant of rice starch gels was influenced by amylose content, but not by gel consistency.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.1
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• pp.89-95
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• 2003

Four-dimensional response surface methodology was used for monitoring the manufacturing characteristics of aloe gel-state food. The optimum conditions predicted for each corresponding sensory properties of aloe gel-state food were 87.38 mL (content of aloe juice), 0.16 g (content of konjac) and 0.19 g (content of carrageenan) in coloror of gel-state food, 83.84 mL, 0.17 g and 0.20 g in aroma of aloe gel-state food, 83.20 mL.0.15 g and 0.27 g taste of aloe gel-state food and 98.95 mL, 0.10 g and 0.23 g in texture of aloe gel-state food. Maximum chewiness of aloe gel-state food was in 113.05 mL aloe juice, 0.27 g konjac and 0.21 g carrageenan. The optimum conditions, which satisfied all sensory properties of gel-state food, were 88.23 mL, 0.15 g and 0.49 g in content of aloe juice, content of konjac and content of carrageenan, respectively.

• Korean journal of food and cookery science
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• v.19 no.6
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• pp.758-764
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• 2003

This study was performed to determine the quality characteristics of mixed polysaccharide gels made from kcarrageenan and locust bean gum with various kiwifruit content after freeze-thawing. The syneresis, rupture properties, TPA properties and sensory properties of the mixed polysaccharide gels with various kiwifruit contents after freeze-thawing were measured. The syneresis of the gel with various kiwifruit contents by freeze-thawing was not significantly different, whereas repeating freeze-thawing resulted in remarkable increase in the syneresis of the mixed polysaccharide gels with 5％, 20％ and 40％ kiwifruit. In terms of the rupture properties, the rupture stress, rupture energy and rupture strain decreased with increasing kiwifruit content after freeze-thawing. In terms of the TPA properties, the adhesiveness, hardness and chewiness increased and the cohesiveness decreased with increasing kiwifruit content after freeze-thawing. The rupture properties, springiness and cohesiveness of the gel by freeze-thawing were lower than those of the gel stored in the refrigerator. In contrast, the gumminess, hardness and chewiness of the gel after freeze-thawing were higher than those of the gel stored in the refrigerator. The results showed that the gel became crumbly and tough as a result of freeze-thawing. In the sensory evaluation, He overall acceptability of the gel after freeze-thawing was highest at the 30％ kiwifruit content, and differences in the sensory properties between the gel after freeze-thawing and that stored in the refrigerator were small. Therefore, mixed polysaccharide gels with kiwifruit after freeze-thawing could be useful despite the small decrease in quality.

• Journal of dental hygiene science
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• v.10 no.2
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• pp.79-83
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• 2010

This study manufactured hydrogel, which was contained NSAIDs(non-steroidal anti-inflammatory drugs) Ketorolac tromethamine and hydrolyzed products of gardeniae fructus extract, and experimented viscosity, surface tension, tensile strength and bio-adhesiveness by using hairless mouse. Thus, it was performed in expectation for being probably able to develop as effective auxiliary agent of periodontal disease after non-surgical or surgical periodontal treatment. As a result, the following conclusions were obtained. 1. Out of KGE and KGH gel materials, the content of ketorolac tromethamine was 1.02~0.97%. The content of geniposide was 0.34% in KGE gel A and C. However, it got lower to 0.11% in KGH gel B and D. The content of genipin wasn't shown in KGE gel A and C, but was shown with 0.13% in KGH gel B and D. 2. As for viscosity according to temperature in gel material, the gel, which used independently Carbopol 940 as gel inoculant, maintained the higher viscosity than the gel, which added Poloxamer 407. The surface tension in each material showed 34.77~40.58 dyne/cm at 37. As for tensile strength in material, KGH gel B was shown the higher tensile strength in about 3.5 times compared to the control group. 3. As for bio-adhesiveness, the back-skin upper part(epidermis) and abdomen skin were shown to be 50.62 N in KGH gel B, thereby having indicated higher value in about 5 times compared to control group. The back-skin lower part(dermis) and abdomen skin were shown to be 35.93 N in KGH gel B, thereby having indicated higher value in about 3.5 times compared to control group.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.1108-1109
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• 2008

To survive in outdoor environments, photovoltaic modules rely on packaging materials to provide requisite durability. We analyzed the properties of encapsulant materials that are important for photovoltaic module packaging. Recently, the thickness of solar cell gets thinner to reduce the quantity of silicon. And the reduced thickness make it easy to be broken while PV module fabrication process. Solar cell's micro cracks are increasing the breakage risk over the whole value chain from the wafer to the finished module, because the wafer or cell is exposed to tensile stress during handling and processing. This phenomenon might make PV module's maximum power and durability down. So, when using thin solar cell for PV module fabrication, it is needed to optimize the material and fabrication condition which is quite different from normal thick solar cell process. Normally, gel-content of EVA sheet should be higher than 80% so PV module has long term durability. But high gel-content characteristic might cause micro-crack on solar cell. In this experiment, we fabricated several specimen by varying curing temperature and time condition. And from the gel-content measurement, we figure the best fabrication condition. Also we examine the crack generation phenomenon during experiment.

• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.1155-1156
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• 2006

In this paper, we analyzed the effect of EVA Sheet Gel Content depending on curing condition for photovoltaic module. Gel Content was measured by manufacturing Glass/EVA Sheet/Back Sheet scheme at several curing temperature and curing time. And the surface analysis of EVA Sheet depending on process condition could be observed using SEM(Scanning Electron Microscope). Through this experiment, we could confirm that there are differences on Gel Content of EVA Sheet and surface configuration depending on curing temperature and curing time. To find out the optical characteristic dependency on curing condition, Class/EVA Sheet/Glass scheme was fabricated. The optical transmittance of EVA Sheet at visible wavelength was enhanced 5% when compared to Glass/Glass scheme. And the transmittance of $130^{\circ}C$/4min, $110^{\circ}C$/4min, $160^{\circ}C$/6min process condition was higher at ultraviolet wavelength range. These curing conditions could be regarded as the best process for suppression the discoloration speed of EVA Sheet under UV light.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.20-21
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• 2006

In this paper, we studied the influence of EVA sheet gel content on photovoltaic module durability. Depending on thermal curing temperature and time during lamination, there are dramatic changes on chemical and physical characteristics. To find the optimum PV module process condition, Glass/EVA/Back Sheet scheme was made. Gel Content, FT-IR spectrum and SEM were used for the detail analysis. From these results, $110^{\circ}C/6min$ and $130^{\circ}C/4min$ lamination condition could be suggested for the best one for durable PV module processing. The further analysis is described in the following paper.

• Elastomers and Composites
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• v.54 no.3
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• pp.247-251
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• 2019

Two different urethane acrylates (mono-acrylate and di-acrylate) were used to prepare unsaturated polyester-based hybrid gel-coats. The physical properties and surface characteristics of these gel-coats were investigated on the basis of the content and type of urethane acrylate. The set-to-touch time increased and the physical properties (surface hardness and tensile strength) decreased with an increase in the urethane acrylate content. However, the type of urethane acrylate did not affect these parameters. It was found that the optimal urethane acrylate content for the application of unsaturated polyester-based hybrid gel-coats is ~10 wt%.