• Environmental Engineering Research
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• 제11권1호
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• pp.1-13
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• 2006

In this study, conventional biofilters packed with flexible synthetic polyurethane (PU) foam carriers were operated to remove toluene from a contaminated air stream. PU foams containing various adsorbents (e.g., zeolite, sepiolite, dolomite and barite) were synthesized for the biofilter media and their adsorption characteristics of toluene were determined. Adsorption capacity of PU-adsorbent foam was in the order of PU-dolomite ${\approx}$ PU-zeolite > PU-sepiolite > PU-barite. During the biofiltration experiment, influent toluene concentration was in the range of 0-160 ppm and EBRT (i.e., empty bed residence time) was 45 seconds. Pressure drop of the biofilter bed was 4-5 mm $H_2O/m$ column height. The maximum removal capacity was in the order of PU-dolomite > PU-zeolite > PU-sepiolite > PU-barite, while the complete removal capacity was in the order of PU-dolomite > PU-sepiolite > PU-zeolite > PU-barite. The better biofiltration performance in PU-dolomite foam was because PU-dolomite foam had lower density and higher porosity than the others providing favorable conditions for microbial growth. The results of biodegradation kinetic analysis showed that PU-dolomite foam had higher maximum removal rate ($V_m\;=\;11.04\;g$ toluene/kg dry material/day) and saturation constant ($K_s\;=\;26.57\;ppm$) than the other PU foams. This supports that PU-dolomite foam was better than the others for biofilteration of toluene.

• 폴리머
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• 제29권3호
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• pp.300-303
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• 2005

폴리우레탄을 PU1000(poly(propylene glycol), PPG, 분자량 1000 g/mol로 제조된 폴리우레탄)과 PU2000(PPG 분자량 2000 g/mol로 제조된 폴리우레탄)을 이용하여 다층구조와 발포체 다층구조로 제조하였고 동력학 특성과 음향특성을 기준물질인 PU1000과 비교 조사하였다. 다층구조 폴리우레탄의 감쇠 피크는 PU1000에 비해 낮은 온도로 이동한 반면에 발포체를 이용한 다층구조에서의 감쇠 피크는 PU1000에 비해 높은 온도로 이동하였고 감쇠 범위 또한 넓어졌다. 음향특성인 투과손실 측면에서 보면 다층구조의 투과손실은 기준이 되는 PU1000에 비해 100 Hz이하와 600 Hz의 특정 주파수 영역에서 효과적이었고 발포체 다층구조의 경우는 실험 범위인 1000 Hz이하 전영역에서 아주 우수한 투과손실이 얻어졌다

• 한국생활과학회지
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• 제24권2호
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• pp.285-295
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• 2015

To identify optimized thermal properties of mold brassiere cup for improved thermal comfort during summer, we compared the thermal resistance and the water vapor permeability of Polyurethane (PU) foam, 3D spacer fabric and the two combined materials of the PU foam and the 3D spacer fabric. Four experimental mold brassieres were made of the materials for wearing test. Six women in their twenties evaluated the wearing sensation in the hot and humid environment. The changes in microclimate temperature and humidity while wearing test brassiere cups were measured. Results indicate that thermal resistance increased as more PU foam were combined, while the water vapor permeability was higher as the content of the 3D spacer fabric increased at thickness of 18mm and over. However, in the wear test, the PU foam brassiere was the most preferred in all ambient conditions due to its soft, flexible and smooth texture, despite its high thermal resistance and low water vapor permeability. This indicates that the textures of mold foams are more dominant properties than thermal properties for mold foams in determining the wear comfort of mold brassieres.

• 한국산학기술학회논문지
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• 제7권3호
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• pp.458-464
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• 2006

토양의 생물학적 복원은 산업화로 무차별하게 오염되어 있는 국내 산업단지 주변과 지하수 환경보전을 위한 경제적 도구로 인식되어왔다. 본 연구는 친환경적 생물복원을 위한 기초자료를 얻기 위하여 유류로 오염된 양토에서 Pseudomonas sp. (KCCM 40055)를 접종한 polyurethane 매체환경을 적용, 유류의 성분중 PAH 분해도를 조사하였다. 다공성 매체로서 재현성이 뛰어나며 미생물 부착에 활용되어 온 polyurethane foam을 사용하여 미생물 부착성을 아울러 조사하였다. 사용된 PU중 최저공극 foam인 SR9-35C/G 의 경우 부착률과 PAH분해율이 가장 높았으며 토양함수율 증가에 따라 그 효율이 증가하였다.

• 한국응용과학기술학회지
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• 제24권2호
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• pp.182-189
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• 2007

Used polyurethane was chemically degraded by treatments with flame retardants such as tris(3-chloropropyl) phosphate (TCPP), triethyl phosphate (TEP), and trimethyl phosphate (TMP). The structure of degraded products (DEP) was analyzed by FT-IR and P-NMR and it turned out to be phosphorus containing oligourethanes. Rigid polyurethane foam was produced by using the degraded products (DEP) as flame retardants. The flammability of recycled rigid polyurethane was investigated. The recycled polyurethane shows a reduced flammability over virgin polyurethane. In order to evaluate flame retardant properties of the recycled polyurethane foams with various amounts of DEP, the combustion parameters of the foam was measured by a cone calorimeter. Scanning electron micrograph of recycled PU shows the same uniform cell morphology as virgin PU.

• 공업화학
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• 제9권5호
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• pp.648-653
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• 1998

본 연구에서는 폴리우레탄 폼의 셀 내부구조 및 크기가 친유성 유체의 흡유능에 미치는 영향을 체계적으로 연구하였다. 우선 다양한 분자량의 폴리올 (GP-1000, GP-3000, GP-4000, GP-5000)을 이용하여 폴리우레탄 폼을 제조하여 그 기본적인 물성을 조사하였다. 폴리올의 분자량이 증가함에 따라 셀 크기가 감소하고 흡유량이 2000% 이상 증가하였다. Surfactant량이 증가하고 흡착되는 유체의 점도가 증가함에 따라 흡유량이 현저하게 감소함을 알 수가 있었다. 또한 폴리올의 분자량이 증가함에 따라 표면강도가 상승하였는데 이는 분자량 증가에 따른 유체점도의 상승이 폼밀도를 증대시킨데 기인한 것으로 해석할 수 있었다. 폼생성시 교반속도가 증가하여도 밀도가 증가하였다.

• Steel and Composite Structures
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• 제20권1호
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• pp.43-56
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• 2016

Polyurethane foam with low density used in sandwich panels is examined in the paper. A series of experiments was carried out to identify mechanical parameters of the foam. Various experimental methods were used for determining the shear modulus, namely a four and three point bending tests (the most common in engineering practice), a double-lap shear test and a torsion test. The behavior of PU in axial compression and tension was also studied. The experiments revealed pronounced anisotropy of the PU foam. An orthotropic model is proposed. Limitations of application of isotropic model of PU in engineering practice is also discussed.

• 폴리머
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• 제34권5호
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• pp.442-449
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• 2010

본 연구에서는 hard segment 함량(%)별로 친수성의 폴리우레탄 프리폴리머를 합성한 후 다양한 발포 혼합 조성액을 이용하여 폴리우레탄 폼을 제조하였다. 그 결과 사슬연장제를 도입한 폴리우레탄 프리폴리머가 도입하지 않은 것에 비해 기계적 물성이 우수하였다. 또한 폴리우레탄 구조에 hard segment 함량(%)을 높임으로써 폴리우레탄의 기계적 물성을 향상시킬 수 있었다. 한편 발포 혼합조성액에서도 F-68, 글리세린, CMC 등의 원료 배합비를 조정함으로써 최종적으로 제조된 폴리우레탄 폼의 기계적 물성과 흡수도, 흡수속도, 모폴로지 등을 조절할 수 있었다. 제조된 폴리우레탄 폼은 세포배양 결과 세포적합성이 우수하였고, 동물실험 결과 대조군인 거즈에 비하여 월등한 창상치유 효과를 보였으므로 창상치료용 소재로서의 적용 가능성이 높음을 알 수 있었다.

• 한국안전학회지
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• 제6권1호
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• pp.26-30
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• 1991

Flammability, and released toxic halogen gases during combustion about two kinds of flame-retardant flexible foam(F.R. flexible PV foam) were investigated. One of the above was F.R. flexible PU foam with the containment of halogen and the other was manufactured with pure flexible PU foam in aqueous solution of alumina trihydrate(ATH) and dried 4 hours at 10$0^{\circ}C$. Flammability by L.O.I and UL94 HF-1 of the two materials were similarly shown. And combustion gases were analyzed with GC-Mass. HCI, CI$_2$ and HF were detected at both halogen being contained F.R. flexible PU foam and ATH dolng one The reason, to find halogen gases from burning ATH-containing F, R. flexible PU foam which wasn't used for any halogenated F.R., could be considered as by using trichlorofluoromethane with blowing agent to make PU foam. The relative quanity of relesed halogen gases of F.R. flexible PU foam with the containment of halogen had been indicated tree times HCI and CI$_2$, two times HF than ATH containing, respectively.

• 한국재료학회지
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• 제23권7호
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• pp.366-372
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• 2013

Flexible polyurethane/clay porous nanocomposite foams were synthesized using natural and organically modified montmorillonite clays such as bentonite, closite 10A and closite 30B. The content of nanoclays was varied from 1 to 5 wt% of polyol. Dispersion of clay in Polyurethane(PU) matrix was investigated by X-ray diffraction(Cu-$K{\alpha}$ rays of wavelength $1.54{\AA}$) using an X-ray diffractometer. Also, we determined that the thermal resistance of PU foam increased with added clay, compared to that of pure PU foam. The cell size and the fraction of open cells of the precursor foam were controlled by the addition of clay to the polyurethane foam. Modified clays were found to be more efficient cell openers than the unmodified clay. In addition, the tensile strength and elongation of the polyurethane/clay porous nanocomposites were examined. Increasing clay content increased the mechanical properties of the composites, such as tensile strength, and elongation at break. However, increasing the content over 5 wt% deteriorated the properties of the composites. We found that the nanofillers(bentonite, closite 10A and closite 30B) improved the thermal stability of the nanocomposite foam. The nanocomposite foam containing 3 wt% of closite 30B exhibited the best tensile strength and thermal stability.