• 한국고분자학회지:고분자과학과기술
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• 제10권5호
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• pp.597-613
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• 1999

• 한국고분자학회지:고분자과학과기술
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• 제8권6호
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• pp.715-720
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• 1997

• Elastomers and Composites
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• 제48권3호
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• pp.195-200
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• 2013

본 연구의 주요 목적은 신발 겉창 재료로 사용하기 위하여 열가소성 폴리우레탄 (TPU)의 내마모성과 습윤시의 내슬립성을 에틸렌-프로필렌-디엔 고무 (EPDM) 또는 폴리부타디엔 고무 (BR)를 블렌드하여 향상시키는 것이다. 10 wt%의 EPDM 또는 BR이 TPU에 투입되었을 때 TPU/EPDM과 TPU/BR 블렌드는 TPU보다 우수한 NBS 내마모도, 인장 물성 그리고 습윤 내슬립성을 보였다. 10 wt% 이상 투입될 때는 내마모도와 인장 물성 모두 감소하였다. 10 wt% 투입시의 내마모도와 인장물성 상승은 TPU의 상분리도 증가에 기인하는 것으로 보인다.

• 접착 및 계면
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• 제14권3호
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• pp.121-127
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• 2013

본 연구에서는 열가소성 폴리우레탄(TPU)과 EPDM, NBR 및 BR을 용융 블렌딩하여 TPU/Rubber 블렌드 필름을 제조하고 이들의 조성이 마찰시 표면 파괴와의 관계를 연구하였다. TPU/EPDM과 TPU/BR 블렌드의 마찰시 표면 파괴 특성이 개선되었으며 특히 BR이 우수하였다. 또한, TPU/BR 블렌드에서 BR의 함량이 10 wt% 이상 투입될 때 표면 파괴 및 마킹 특성이 개선되었다. Scanning electron microscopy (SEM) 분석으로부터 BR 함량이 증가할수록 연질상의 증가로 인한 표면 파괴 및 마킹 특성의 개선으로 추정할 수 있었다.

• Elastomers and Composites
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• 제54권3호
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• pp.225-231
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• 2019

Bio-based polyester polyol was synthesized via esterification between azelaic acid and isosorbide. After esterification, bio-based polyurethanes were synthesized using polyester polyol, 1,3-propanediol as the chain extender, and 4,4'-diphenylmethane diisocyanate, in mixing ratios of 1:1:1.5, 1:1:1.8, 1:1:2, and 1:1:2.3. The bio TPU (Thermoplastic Polyurethane) samples were characterized by using FT-IR (Fourier Transform Infrared Spectroscopy), TGA (Thermal Gravimetric Analysis), DSC (Differential Scanning Calorimetry), and GPC (Gel Permeation Chromatography). The mechanical properties (tensile stress and hardness) were obtained by using UTM, a Shore A tester, and a Taber abrasion tester. The viscoelastic properties were tested by an Rubber Processing Analyzer in dynamic strain sweep and dynamic frequency test modes. The chemical resistance was tested with methanol by using the swelling test method. Based on these results, the bio TPU synthesized with the ratio of 1:1:2.3, referred to as TPU 4, showed the highest thermal decomposition temperature, the largest molecular weight, and most compact matrix structure due to the highest ratio of the hard segment in the molecular structure. It also presented the highest tensile strength, the largest elongation, and the best viscoelastic properties among the different bio TPUs synthesized herein.

• 한국의류학회지
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• 제46권3호
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• pp.481-493
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• 2022

This study investigated process conditions for 3D printing through manufacturing thermoplastic polyurethane (TPU) samples under different infill conditions. Samples were prepared using a fused deposition modeling 3D printer and TPU filament. 12 infill patterns were set (2D: grid, lines, zigzag; 3D: triangles, cubic, cubic subdivision, octet, quarter cubic; 3DF: concentric, cross 3D, cross, honeycomb), with 3 infill densities (20%, 50%, 80%). Morphology, actual time/weight and compressive properties were analyzed. In morphology: it was found that, as infill density increased, the increase rate of the number of units rose for 2D and fell for 3DF. Printing time varied with the number of nozzle movements. In the 3DF case, the number of nozzle movements increased rapidly with infill density. Sample weight increased similarly. However, where the increase rate of the number of units was low, sample weight was also low. In compressive properties: compressive stress increased with infill density and stress was high for the patterns with layers of the same shape.

• 한국정밀공학회지
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• 제30권3호
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• pp.317-323
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• 2013

In-mold coating is a reactive fluid designed to improve the surface quality of injection molded thermoplastic substrate in functional and cosmetic properties. In this study, a mixing head for in-mold coating was designed, and mixing characteristics of two-component polyurethane flowing through runner were investigated based on flow simulations. In order to achieve uniform mixing of two components injected through straight mixing head, an impingement aftermixer was used in runner design. Semi-circular cross-section was better than circular one for runners for uniform mixing. With increasing runner length and flow rate, mixing became more uniform. In addition, the degree of mixing was more improved with decreasing viscosity of isocyanate.

• 폴리머
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• 제29권2호
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• pp.140-145
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• 2005

열가소성 폴리우레탄(thermoplastic polyurethane: TPU)의 제조에 사용한 폴리올 종류와 경질부 함량에 따른 TPU의 결정화 거동을 고찰하였다. TPU의 제조에 사용한 폴리올은 분자량이 2000인 poly(tetamethylene ether glycol) (PTMEG), poly(propylene glycol)(PPG) diol, polycaprolactone(PCL) diol, poly(butylene adipate)(PBA) diol을 사용하였으며, 경질부 함량은 $35\~44\;wt\%$였다. TPU의 경질부 냉각 결정화는 경질부 함량이 많을수록 고온에서 관찰되었다. TPU의 등온 결정화 속도는 경질부 함량이 많을수록 빠르고, TPU 제조에 사용한 폴리올 종류별로는 $PTMEG>PPG>PCI{\geqq}PBA$ 경향이 나타나, 연질부와 경질부의 상용성이 낮을수록 용융상태에서 경질부의 수소결합이 용이하고 결정화 속도가 빠르며, 냉각 결정화가 고온에서 나타나는 것으로 해석하였다.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2001년도 가을 학술발표회 논문집
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• pp.9-12
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• 2001

Blending is an easy and popular means to achieve a desired set of characteristic properties. The blends, by melt mixing of thermoplastic materials and elastomer, have received considerable attention in recent years. It is well known that nearly all blends comprise one polymer domain dispersed in the matrices of the other polymer [1]. (omitted)

• Macromolecular Research
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• 제10권6호
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• pp.365-368
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• 2002

Thermoplastic polyurethanes (TPUs) with different hard segment length has been prepared from a fixed molar ratio of poly(tetramethylene ether glycol), 4,4'-diphenylmethane diisocyanate, and 1,4-butanediol by different polymerization procedures. Results reveal that the on-set temperature of endotherms ( $T_{cc}$ ) due to the crystallization of hard segments by cooling the TPUs from melt and the peak temperature of endotherms due to the melting of hard segments ( $T_{mh}$ ) by heating the TPUs increased and levelled off with increasing the hard segment length of TPUs. It has also been observed that soft segment glass transition temperature ( $T_{gs}$ ) of TPU decreased slightly with increasing the hard segment length, which explains less mixing of soft segments and hard segments. In tensile measurement of TPUs, strain hardening is observed with increasing the hard segment length, which is attributed to the strain induced crystallization of soft segments.