• 접착 및 계면
• /
• 제9권4호
• /
• pp.12-16
• /
• 2008

핫멜트 접착제는 상온에서 고체상태로 존재하나 열에 의하여 활성화되어 지압 정도의 압력으로 접착이 가능하다. 또한 접착속도가 빠르고 공정의 자동화가 가능하며 친환경적인 장점을 가지고 있다. 본 연구에서는 SBS와 석유수지의 종류 및 이들의 조성비가 핫멜트 접착제의 물성에 미치는 영향을 알아보았다. 핫멜트 접착제의 스타이렌 함량 및 $C_9$계 석유수지의 함량이 증가함에 따라 점도, 인장강도, 접착력 및 내열성 등이 증가하는 경향을 나타내었다.

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

• 한국지역사회생활과학회지
• /
• 제22권3호
• /
• pp.365-377
• /
• 2011

The dual purposes of this study were to investigate footwear worn by college students who have become spoilt for choice in apparel & shoes, and point out the problems of their shoe-wearing habbits. The survey was administered in October, 2010 to 600 college residents in Kwangju-Jeonnam area and the results are as follows. Firstly, the most frequently worn footware by males were sneakers, followed by dress shoes and oxford shoes. Females followed a similar trend with sneakers being the most frequently worn, followed by high heeled shoes, flat shoes, wedge high heeled shoes and chucker boots. Secondly, both male and female students thought that the most comfortable and favorable shoes for them were sneakers and the most uncomfortable ones were high-heeled shoes and sandals. They thought chucker boots were both fashionable and comfortable. Thirdly, the degree of unsatisfaction for shoes was relatively high and the influencing factors for unsatisfaction were uncomfortable soles, aches around the toes and a frontward leaning posture of the body, etc. Finally, 87% of the female subjects who had experience wearing high-heeled(over 7cm height) shoes showed a significant increase in foot disorders than those who had never worn high-heeled shoes. According to the results, it is necessary to educate proper selection and wearing of footwear in order to prevent foot disorders and maintain overall health of the body.

• 접착 및 계면
• /
• 제12권1호
• /
• pp.11-15
• /
• 2011

본 연구에서는 저독성 용제에 용해도가 있는 열가소성 폴리우레탄(TPU, Thermoplastic Polyurethane)을 합성하고 폴리우레탄 합성시 사용되는 사슬연장제 및 NCO/OH 비에 따른 물성 변화를 알아보았다. 또한 합성된 열가소성 폴리우레탄을 이용하여 난접착재질용 저독성 프라이머를 제조하고 접착특성을 알아보고자 하였다. TPU 합성시 r(NCO/OH) = 2.0 이상인 경우에는 폴리올 및 이소시아네이트의 종류에 관계없이, 저독성 용제에 용해도가 저하되는 결과를 나타냈으며, non polar한 구조를 가지고 있는 접착증진제보다는 polar한 구조를 가지고 있는 접착증진제의 접착력이 우수하게 나타났다.

• 한국운동역학회지
• /
• 제17권3호
• /
• pp.105-114
• /
• 2007

The purpose of this study was to compare the biomechanical difference of barefoot and two types taekwondo footwear. which will provide scientific data to coaches and players, to further prevent injuries and to improve each players skills. How to an effect on human body which studied a kinematics and kinetics from 8 college students during experiments. This study imposes several conditions by barefoot and two types of taekwondo footwear ran under average $2.56{\pm}0.21\;m$/sec by motion analysis, ground reaction force and electromyography that used to specific A company. First of all, motion analysis was caused by achilles tendon angle, angle of the lower leg, angle of the knee. The result of comparative analysis can be summarized as below. Motion analysis showed that statically approximates other results from achilles tendon angle (p<.01), initial ankle angle(p<.05), initial sole angle(p<.001) and barefoot angle(p<.001). Ground reaction force also showed that statically approximates other results from impact peak timing (p.001), Maximum loading rate(p<.001), Maximum loading rate timing (p<.001) and impulse of first 20 percent (p<.001). showed that averagely was distinguished from other factors, and did not show about that.

• Elastomers and Composites
• /
• 제40권4호
• /
• pp.242-248
• /
• 2005

스포츠화 중창용으로 사용되는 세가지 종류의 발포체인 PU, IP 및 PH의 경도가 피로특성에 미치는 영향을 검토하였다. 세 가지 종류의 발포체를 50 rpm으로 50,000번 반복 압축하였으며, 발포체의 셀은 반복압축에 따라 형태가 변형되었다. 셀 변형의 정도는 IP의 경우가 PH나 PU 보다 큰 것으로 나타났다. 반복압축에 의해 발포체에서 영구변형이 나타났으며, IP가 PH나 PU 보다 크게 나타났다. 반복압축에 따라 세 가지 종류의 발포체의 최대압축력은 감소하는 경향을 나타내었으며, IP의 경우 가장 현저한 감소를 나타내었다. 세 가지 종류의 발포체는 경도가 증가함에 따라 최대압축력의 저하가 더욱 큰 것으로 나타났다.

• 접착 및 계면
• /
• 제8권4호
• /
• pp.8-13
• /
• 2007

본 연구에서는 teramethylxylene diisocyanate (TMXDI)와 poly(tetramethylene glycol) (PTMG), polycarprolactone (PCL), dimrthylol proponic acid (DMPA)를 사용하여 무용제형 수분산 폴리우레탄을 합성하였으며, 음이온성기의 함량이 열적, 기계적 물성 및 접착력에 미치는 영향을 검토하였다. 합성된 무용제형 수분산 폴리우레탄의 Tg는 $-70{\sim}-50^{\circ}C$ 범위이고 PCL의 함량이 증가함에 따라 Tg는 상승하였다. 인장강도와 접착력, 열 안정성은 PCL과 음이온성기의 함량이 증가함에 따라 증가하였고 신율은 감소하였다.

• 한국염색가공학회지
• /
• 제30권4호
• /
• pp.321-328
• /
• 2018

Wet polyurethane resin was synthesized by using polytrimethylene ether glycol prepared from 1,3-propanediol produced by fermentation from corn sugar as bio polyol and polyether-polyol(PTMG). Physical properties and cell characteristics by wet coagulation were investigated using the synthesized wet polyurethane resin. The tensile strength of wet polyurethane resin decreased with increasing content of bio polyol as copolymer polyol, but it tended to increase elongation at break and tear strength. As a result of thermal characteristic analysis, it was found that the glass transition temperature was slightly increased as the content of bio polyol increased. As a result of comparing the cell characteristics by the wet coagulation method, it was found that the shape of the cell was good when the ether polyol and the bio polyol were used alone.

• 한국의류학회지
• /
• 제43권4호
• /
• pp.532-548
• /
• 2019

This study examines Geumgwan Gaya's headgear, belt, and footwear. The relics excavated from tombs were examined first, then earthenware and clay figurines, followed by the visual data of related neighboring countries. The results are as follows. The headgear of Geumgwan Gaya, identified in the relics, is daegwan (帶輪式立飾冠) and lip (笠). Daegwan is a diadem with branch-shaped ornaments. It has an organic cap with fabric and leather as well as ties the strings to both ends of the diadem. Lip can be seen in the mounted figure of the earthenware. In neighboring countries, the top of lip is round or straight, but Geumgwan Gaya's lip is pointed and curved slightly backward. In addition, from neighboring countries' data, it is considered that the conical hat and gun (巾) are worn in Geumgwan Gaya. The belt is made of cloth or leather. Geumgwan Gaya also uses a belt with an animal-shaped hook and Jin style belt. Jin style belt shows the association with three-Yan culture of the Seonbi people in patterns and forms. Footwear of Geumgwan Gaya is li (履) and boots. Li included leather shoes, lacquer shoes, straw shoes and wooden shoes. In addition, there are leather boots decorated with round ornaments.

• Elastomers and Composites
• /
• 제55권4호
• /
• pp.270-276
• /
• 2020

The long-term durability of an FKM O-ring used as parts of a hydrogen station was investigated by exposing it to high-pressure gaseous hydrogen for 1, 3, and 7 days at room temperature. Changes in its sealing force were subsequently measured at 150℃ using intermittent compression stress relaxation (CSR). No changes in the tensile properties of FKM O-ring were observed, but its initial and overall sealing forces at 150℃ significantly decreased with increasing exposure time to hydrogen gas. Microvoid formation in the FKM O-ring upon exposure to high-pressure hydrogen was minimized over time after the ring was exposed to atmospheric pressure at room temperature, which prevented changes in its tensile properties. However, applying heat accelerated FKM O-ring oxidation, which decreased its sealing force. These results indicated that identifying changes in the sealing force of rubber materials using intermittent CSR is not sufficient for monitoring changes in mechanical properties under high-pressure hydrogen atmospheres; however, it is suitable for evaluating the long-term durability of sealing materials for hydrogen station applications under similar conditions.