• Journal of Forest and Environmental Science
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• 제31권4호
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• pp.297-302
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• 2015

With the intention to solve environmental problems caused by synthetic plastics from petroleum resources, biodegradable polyurethane foams and thermosetting moldings were prepared from biomass, such as wood and wheat bran by liquefaction method. Biodegradability of these biomass-based polymeric materials was investigated. In activated sludge, polyurethane foams from liquefied wheat bran and thermosetting molding from phenolated wood were decomposed approximately 14% and 29% for 20 days, respectively. One of the wood fungi, Coriolus versicolor was able to grow without supplemental nutrition, only with distilled water and polyurethane foam as a nutrition source. Risk assessments were also conducted and results showed that estrogenicity, mutagenicity, and carcinogenicity were not observed in the extractives of biomass- based polymeric materials.

• Elastomers and Composites
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• 제52권4호
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• pp.249-256
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• 2017

The history of polyurethane is relatively shorter compared to that of the other polymers, though its importance has grown rapidly. Due to its unique properties, polyurethanes are widely applied in various fields. In particular, the automotive industry is one of the important application fields. To date, polyols and isocyanates used in the polyurethane industry are generally of petrochemical origin. Recently, owing to the oil crisis, legislation, and growing awareness towards environmental preservation, the demand for more sustainable and eco-friendly raw materials has increased. In this paper, the latest research and development trends in polyurethane applications were reviewed, with a focus on the automobile industry in areas such as seat comfort, noise reduction, light weight, biomass-based polyurethane, and recycling.

• 공업화학
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• 제24권6호
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• pp.579-586
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• 2013

화석 연료의 고갈 및 온실가스 배출문제로 인해 보다 환경 친화적인 바이오매스 유래의 고분자 생산에 대한 연구가 진행되고 있다. 폴리우레탄은 -OH 화합물과 -NCO 화합물의 중합반응에 의해 생성된 우레탄(-NHCOO-) 결합을 포함하는 고분자 화합물을 통칭하며 자동차, 건축, 화학 분야에서 가장 광범위하게 사용된다. 폴리우레탄의 원료인 폴리올과 이소시아네이트는 식물성 천연유지, 셀룰로오스, 리그닌 등 재생 가능한 바이오매스로부터 생산이 가능하다. 식물성 천연유지 유래의 바이오폴리올은 이미 상업적 규모로 생산되고 있다. 본 총설은 다양한 바이오매스로부터 바이오폴리올, 바이오이소시아네이트, 이소시아네이트 대체화합물 관련 최신 기술개발 동향 및 이를 기반으로 합성된 바이오폴리우레탄의 특성을 평가하고, 바이오폴리우레탄의 응용분야와 함께 전망을 분석하였다.

• Elastomers and Composites
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• 제54권4호
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• pp.279-285
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• 2019

Bio-based polyester polyols were synthesized using esterification with azelaic acid, sebacic acid, and 1,3-propanediol. Polyurethanes were prepared using chain extenders (1,4-Butanediol, 1,3-Propanediol, and isosorbide) and 4,4'-diphenylmethane diisocyanate with a mixing ratio of 1:1:1.1. Subsequently, the properties of the polymers prepared using the different chain extenders were compared. The synthesis of polyurethane was confirmed by FT-IR, TGA, and GPC. The mechanical properties (hardness, ball rebound, and tensile strength) of the materials were analyzed using shore A tester, taber abrasion, and UTM. heat, chemical, and water resistances of the prepared materials were measured by comparing the tensile strengths according to external changes.

• Journal of the Korean Wood Science and Technology
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• 제52권3호
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• pp.221-233
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• 2024

Lignin, a prominent constituent of woody biomass, is abundant in nature, cost-effective, and contains various functional groups, including hydroxyl groups. Owing to these characteristics, they have the potential to replace petroleum-based polyols in the polyurethane industry, offering a solution to environmental problems linked to resource depletion and CO₂ emissions. However, the structural complexity and low reactivity of lignin present challenges for its direct application in polyurethane materials. In this study, Kraft lignin (KL), a representative technical lignin, was fractionated with ethanol, an eco-friendly solvent, and mixed with conventional polyols in varying proportions to produce polyurethane films. The results of ethanol fractionation showed that the polydispersity of ethanol-soluble lignin (ESL) decreased from 3.71 to 2.72 and the hydroxyl content of ESL increased from 4.20 mmol/g to 5.49 mmol/g. Consequently, the polyurethane prepared by adding ESL was superior to the KL-based film, exhibiting improved miscibility with petrochemical-based polyols and reactivity with isocyanate groups. Consequently, the films using ESL as the polyol exhibited reduced shrinkage and a more uniform structure. Optical microscope and scanning electron microscope observations confirmed that lignin aggregation was lower in polyurethane with ESL than in that with KL. When the hydrophobicity of the samples was measured using the water contact angle, the addition of ESL resulted in higher hydrophobicity. In addition, as the amount of ESL added increased, an increase of 7.4% in the residual char was observed, and a 4.04% increase in Tmax the thermal stability of the produced polyurethane was effectively improved.

• 한국염색가공학회지
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• 제31권3호
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• pp.165-176
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• 2019

Polyurethane-ureas(PUUs) were prepared from 4,4'-methylenebis(cyclohexyl isocyanate) and various diols including isosorbide. Isosorbide is starch-derived monomer that exhibit a wide range of glass transition temperature and are therefore able to be used in many applications. PUU was synthesized by a pre-polymer polymerization using a catalyst. Successful synthesis of the PUU was characterized by fourier transform-infrared spectroscopy. Thermal properties were determined by differential scanning calorimetry, thermogravimetric analysis, and dynamic mechanical analysis. It was found that by tuning isosorbide content in the resin, their glass transition temperature(Tg) slightly decreased. Physical properties were also determined by tensile strength and X-ray diffraction. There is no significant differences between petroleum-derived diol and isosorbide in XRD analysis. Moreover, their physical and optical properties were determined. The result showed that the poly(tetramethylene ether glycol)/isosorbide-based PUU exhibited enhanced tensile strength, transmittance, transparency and biodegradability compared to the existing diols. After 11 weeks composting, the biodegradability of blends increased in ISB-PUU. The morphology of the fractured surface of blend films were investigated by scanning electron microscopy.