• 대한기계학회논문집A
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• 제35권9호
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• pp.1027-1033
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• 2011

VCM 강판은 용융아연도금강판 위에 PET/PVC 코팅하여 가전제품의 외판 소재로 사용되고 있다. 본 연구에서는 VCM 강판의 프레스 성형 중 발생하는 PET 코팅층의 찢김을 저감하기 위해 프레스 성형공정변수를 재설계하였다. 프레스 공정변수들이 PET 코팅층의 찢김에 미치는 영향을 분석하기 위해 유한요소해석을 수행하였다. PET 코팅의 찢김 현상은 드로잉 성형시 제품의 코너부 소재두께의 증가로 인해 금형과 소재 사이의 과도한 마찰에 의해 발생한다. 이를 해결하기 위해 블랭크 형상의 변경을 통해 드로잉성형시 코너부의 소재두께 증가를 저감하였으며, 트리밍 공정시 플랜지부의 과도한 두께 증가부분을 제거하여 플랜지 성형시 소재두께가 금형간극 이하로 분포하도록 하였다. 또한 성형실험과 유한요소해석을 통해 재설계된 공정변수들을 검증하였다. 이를 통해 PET 코팅의 찢김이 없는 양호한 최종제품의 성형이 가능함을 확인하였다.

• 한국응용과학기술학회지
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• 제13권3호
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• pp.137-144
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• 1996

Durable softening water repellents such as PODCW, PDDCW, and PEDCW were prepared by blending cationized polymers, fatty carbamide, waxes, and emulsifiers. The cationized polymers included poly (octadecyl methacrylate-co-2-diethylaminoethyl methacrylate) [PODC], poly (n-dodecyl methacrylate-co-2-diethylaminoethyl methacrylate) [PDDC]and poly (2-ethylhexyl methacrylate-co-2-diethylaminoethyl methacrylate) [PEDC]. After the PET fabrics were treated with these water repellents, water repellency, softness, and durability of the PET fabrics were examined by various methods : water repellency by the hydrostatic pressure and the contact angle methods, softness by crease recovery and tearing strength, and durability by washability, respectively. Rating of water repellency of PET fabrics treated with PODCW was $80^{+}$, but those treated with PDDCW and PEDCW were not high enough to be used in industry.

• 한국염색가공학회지
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• 제32권3호
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• pp.176-183
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• 2020

In order to study wearable air cushion materials capable of responding to massive impact in high-altitude fall situation, high tenacity woven fabrics were bonded by heat only depending on various type of thermoplastic films and then mechanical properties were measured. Tensile strength, elongation, and 100% modulus measurement results for 4 types of films show that TPU-2 has higher impact resistance and easier expansion than PET-1. After thermal bonding, the combination with the highest tensile strength was a material with a TPU-2 film for nylon and a PET-2 film for PET, so there was a difference by type of fabric. The tear strength of the bonded materials were increased compared to the fabric alone, which shows that durability against damage such as tearing can be obtained through film adhesion. All of the peel strengths exceeded the values required by automobile airbags by about 5 times, and the TPU-2 bonded fabric showed the highest value. The air permeability was 0 L/dm2 /min. For both the film and the bonded material, which means tightness between the fabric and the film through thermal bonding. It is expected to be applied as a wearable air cushion material by achieving a level of mechanical properties similar to or superior to that of automobile airbags through the method of bonding film and fabric by thermal bonding.