• 폴리머
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• 제30권4호
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• pp.350-356
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• 2006

실리콘/아크릴수지를 기반으로 한 내후성 도료의 조성이 물성에 미치는 영향을 연구하기 위하여 안료분산 용 및 희석용 실리콘/아크릴수지의 배합비를 중량비율 2 : 8, 3 : 7, 4 : 6 의 3종으로 변화시키면서 내후성 도료를 제조하였다. 제조된 도료의 도막물성 및 내후성이 판단할 수 있는 각종 도막실험을 실시한 결과, 실리콘 성분함량이 증가할수록 열적안정성, 염수분무 및 내후성 등이 향상되었으며, 적정배합비는 2 : 8임을 알 수 있었다. 또한 실리콘 성분을 30 wt% 함유한 도료는 고내후성을 보유함을 확인하였다.

• Archives of Plastic Surgery
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• 제42권1호
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• pp.20-27
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• 2015

Background Hypertrophic scars and keloids are associated with abnormal levels of growth factors. Silicone gel sheets are effective in treating and preventing hypertrophic scars and keloids. There has been no report on the change in growth factors in the scar tissue following the use of silicone gel sheeting for scar prevention. A prospective controlled trial was performed to evaluate whether growth factors are altered by the application of a silicone gel sheet on a fresh surgical scar. Methods Four of seven enrolled patients completed the study. Transforming growth factor (TGF)-${\beta}1$, platelet-derived growth factor (PDGF), and basic fibroblast growth factor (bFGF) were investigated immunohistochemically in biopsies taken from five scars at 4 months following surgery. Results In both the epidermis and the dermis, the expression of TGF-${\beta}1$ (P=0.042 and P=0.042) and PDGF (P=0.043 and P=0.042) was significantly lower in the case of silicone gel sheet-treated scars than in the case of untreated scars. The expression of bFGF in the dermis was significantly higher in the case of silicone gel sheet-treated scars than in the case of untreated scars (P=0.042), but in the epidermis, the expression of bFGF showed no significant difference between the groups (P=0.655). Conclusions The levels of TGF-${\beta}1$, PDGF, and bFGF are altered by the silicone gel sheet treatment, which might be one of the mechanisms of action in scar prevention.

• Archives of Plastic Surgery
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• 제36권2호
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• pp.183-187
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• 2009

Purpose: Because of the volume of elective sterilizations performed in the world during the past decade, the vasectomy was a popular method for male sterilization in Korea and this, in turn, had been followed by an increase in the number of patient requiring vasectomy reversal with the high rate of subsequent divorce and remarriage. Recently, many authors have reported high success rates of vasovasostomy using microsurgical techniques and we performed modified two layer vasovasostomy with intravasal silicone tube to increase postoperative patency and pregnacy rate. Methods: Microscopic vasovasostomy was performed in 9 patients and their average age was $35.78{\pm}1.36years$(from 28 years to 44 years) from June 2006 to June 2008 at our department using modified two layer vasovasostomy with silicone tube insertion. Standard Guibor silicone tube, consisting of two 17.7 cm, 0.064 cm diameter, malleable, stainless steel probes connected by 29 cm of silicone tubing wedged onto disposable probes, were used in all cases. Results: Success rates were 88.8 % for patency and pregnancy 44.4 % for pregnancy in modified two layer vasovasostomy with silicone tube insertion. The patency rates were higher in cases of long postoperative day and in cases of short duration of vasectomy and vasovasostomy. Conclusion: We used a modified method to correspond the patency and pregnancy rate in microscopical modified two layer vasovasostomy using the intravasal silicone tube permanently. This method brings normal patency in microsurgical vasovasostomy because the silicone tube prevent obstruction of anastomosed site of the vas permanently.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
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• pp.51-54
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• 2002

폴리머 애자용 Shed 재료의 전기방전에 대한 열화내성과 표면발수성은 제품의 장기성능에 있어서 가장 중요한 물성들이다. 그러나 무기보강재의 첨가량이 많아 무결점 성형성을 만족하도록 하기 위해서 Process Oil의 사용이 불가피한데 사용하는 오일의 종류와 양에 따라 옥외절연물의 장기성능에 영향을 주는 표면발수성이나 방전내성은 크게 차이가 나는 것으로 밝혀져 있다. 본 논문에서는 화학적 구조와 점도가 다른 몇 종의 hydroxy silicone oil(HS 오일)을 혼련 (kneading) 하는 과정에 첨가하여 이들 오일의 종류와 양이 고무의 기본적인 물성, 발수성, 방전열화내성， 내트래킹성 등에 어떻게 영향을 주는가를 조사하였다. 코로나 처리시간에 따라서 접촉각의 저하정도와 코로나 처리 후 경과시간에 따른 발수성의 회복특성을 조사하였다. HS 오일의 접도에 따라 초기발수성, 발수성 회복특성의 차이가 많았다. 점도가 낮을수록 초기 발수성 저하는 크며 회복속도는 빠른 반면 점도가 높을수록 초기 발수성 저하는 작은 반변은 발수성 회복속도는 다소 느리게 나타났다 내트래킹성 결과는 점도가 높을수록 우수한 특성을 보였다. 결론적으로 폴리머 애자용 실리콘고무의 컴파운딩에서 실리콘오일의 선택은 성형작업성, 발수성회복특성, 열화내성 외에 가격 등을 고려하여 최적화가 필요하다.

• 폴리머
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• 제27권1호
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• pp.3-8
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• 2003

말단에 수소화물기가 치환된 폴리실록산과 알릴 메타크릴레이트와의 히드로실릴레이션 반응을 통하여 폴리실록산 메타크릴레이트를 합성하였다. 또한 산 촉매 하에서 옥타메틸사이클로테트라실록산의 개환-부가반응을 통하여 분자량이 증가된 폴리실록산 메타크릴레이트을 합성하였다. 합성된 폴리실록산 메타크릴레이트는 $^1$H- 및 $^{29}$ Si-NMR로 구조를 확인하였다. 폴리실록산 메타크릴레이트는 실리콘 오일과 균일하게 혼합되었으며, 이 용액을 광 가교시켜 액상인 실리콘 오일이 수 백 nm 정도의 크기로 고르게 미세상분리된 폴리실록산 복합체 필름을 제조할 수 있었다. 주사전자현미경(SEM)을 이용한 모폴로지 관찰로부터 실리콘 오일의 함량이 작을수록, 매트릭스 물질인 폴리실록산 메타크릴레이트의 분자량이 낮을수록, 그리고 분산상 물질인 실리콘 오일의 분자량이 낮을수록 대체적으로 분산상의 크기가 작아짐을 확인하였다

• 대한기관식도과학회지
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• 제15권1호
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• pp.50-55
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• 2009

Objectives: Endoscopic airway dilatation and stenting has been developed to treat the airway stenosis without potential morbidities of open surgery. We report the clinical results of endoscopic airway dilatation with silicone stenting in patients with posttuberculous bronchial stenosis(PTBS) and with severe main tracheal stenosis who have poor general conditions Methods : A prospective observation study of five patients, who have undergone endoscopic airway dilatation and silicone stenting between Feb 2007 and Feb 2009. A total of twelve patients were treated with endoscopic airway dilatation, among them 5 patients were included in this study. three patients were treated with newly designed silicone stent (Natural stent: TNO Co., Seoul, South Korea) because of poor surgical conditions and longer stenotic segment Results: 3 patients were grade III PTBS, and the other 2 patients were grade IV post tracheotomy main tracheal stenosis. One patient of PTBS were treated with silicone stent following endoscopic dilatation because of longer stenotic segment. Two patients of main tracheal stenosis patients were treated with silicone stent because of tracheal lumen collapse. There was no severe postoperative complications except mild granulation tissue formations Conclusions : Endoscopic dilatation including silicone stenting could be a useful method for treating patients with PTBS, and for main tracheal stenosis patients with poor general surgical conditions

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2011년도 춘계학술대회 논문집
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• pp.893-894
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• 2011

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 D
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• pp.1605-1607
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• 1999

Silicone rubber have presently been using in large number for a variety of outdoor HV applications. Silicone rubber have the properties of low surface energy and are able to retain its hydrophobicity or water repellency, thereby suppress the leakage current in the present of moisture and contamination. In this paper, we investigated the recovery characteristics of silicone rubber by measuring the leakage current under salt-fog.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 D
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• pp.1596-1598
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• 1999

In order to determine what influences the interfacial breakdown between two internal dielectric surfaces. We studied the interfacial breakdown phenomena at several interfacial conditions. With the increase of interfacial pressure, at first breakdown strength in interfaces was increased, and then saturated. Breakdown strength in interface pasted with silicone oil was higher than that with silicone grease. As a function of heat treatment time in a vacuum oven interfacial breakdown strength was increased much in XLPE/EPDM laminates pasted with silicone grease but increased a little in that with silicone oil. As an increase of curing agent in silicone oil and grease, breakdown strength in interfaces was increased and then saturated.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 D
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• pp.1651-1653
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• 1999

Room Temperature Vulcanizing (RTV) Silicone Rubber has been widely used to coat porcelain insulator to prevent formation water filming on insulator surface. and RTV silicone rubber has water repellency to suppress leakage current and consequent flashover. RTV silicone rubber's surface has been degradated by outdoor condition such as dust, salt, and water. etc. ESDD(Equivalent Salt Deposit Density) and leakage currents are increased by polymer surface toughness and degradation. In this paper, we investigated relations of surface toughness, ESDD, and leakage currents.