In order to maximize the function and increase the compatibility of silicone hydrogel lens, this study compared and analyzed the properties of Amino modified silicone oil using mini and microemulsion technique, respectively. Optical and physical properties were evaluated by spectral transmittance, refractive index, water content, oxygen transmittance and contact angle measurements to evaluate the performance of the manufactured hydrogel lens. The spectral transmittance results revealed the copolymerization method lens showed 31 % of the visible light area, which did not satisfy the basic optical properties. However, the lens using the mini and microemulsion materials showed more than 90 % of the visible light area, satisfying the optical characteristics. In addition, all physical properties were superior to a basic hydrogel lens. The mini and microemulsion techniques effectively improved the stability and function of the ophthalmic hydrogel lens and are considered a promising ways of manufacturing an ophthalmic hydrogel contact lens with increased compatibility and stability.

Dimethyl silicone oil is widely used due to its excellent thermal stability and good wetting properties. In this study, a series of thermal conductive materials was prepared by physically blending and chemically loading graphene as a thermal conductive filler into dimethyl silicone oil, and their thermal conductivity and tribological properties were investigated. The thermal conductivity of the composites was tested by a thermal conductivity meter and a thermal imaging camera, while the tribological properties of the composites were evaluated using a CSM friction and wear tester. The results showed that both thermal conductivity and tribological properties were improved to a certain extent. The particle size and amount of graphene had a significant influence on the thermal conductivity. For graphene with a single particle size, the thermal conductivity increased with increasing graphene content. The friction coefficient under dry friction conditions was significantly reduced by adding graphene to the silicone oil, as revealed by the friction and wear test.

Abstract Purpose : In this study, α-Lipoic acid and pyridine were added to hydrogel materials and silicone hydrogel materials, respectively, to manufacture contact lens to evaluate changes in physical properties. Methods : N,N-Dimethylacrylamide (DMA), 2,2'-Azobis (2-methylpropionitrile) (AIBN), an initiator, and Ethylene glycol dimethacrylate (EGDMA), crosslinking agent, were used basic mixing ratio, and hydrogel materials were prepared by thermopolymerization at 100°C for 1 hour based on 2-Hydroxyethyl methacrylate (HEMA). Silicone hydrogel materials were prepared by thermopolymerization at 130°C for 2 hours based on Silicone monomer (SID). The properties of contact lenses were evaluated by adding 0.05% of 3-hydroxypyridine N-oxide and (R)-(+)-α-Lipoic acid by ratio to each material. Results : A lens manufactured by adding alpha lipoic acid to silicone hydrogel materials showed a tendency to increase wettability and decrease refractive index. A lens manufactured by adding pyridine to silicone hydrogel materials showed UV-A blocking ability, and the refractive index tended to increase. In addition, a contact lens manufactured by adding alpha lipoic acid and pyridine together showed antimicrobial properties, reduced surface roughness, and increased wettability and oxygen permeability according to the ratio of alpha lipoic acid addition. Conclusion : It is judged that alpha lipoic acid and pyridine are expected to improve wettability and oxygen permeability of the lens and to be used as contact lens materials with antibacterial properties. Key words : Alpha lipoic acid, Antimicrobial, Oxygen permeability, Pyridine, Wettability

The physical and antibacterial properties of ophthalmic lenses fabricated by copolymerization with hydrogel monomers using two types of graphene were measured, and their usability as contact lens materials was analyzed. For polymerization, silicone monomers, including SID-OH, 3-(methacryloxy)propyl tris(trimethylsiloxy)silane, and decamethylcyclopentasiloxane, were used, and N,N-dimethylacetamide, ethylene glycol dimethacrylate as a crosslinking agent, and azobisisobutyronitrile as an initiator were added. Also, graphene oxide nanoparticle (GON) and graphene nanoplate (GNP) were used as an additive, and the physical properties of the lenses fabricated after copolymerization were evaluated. The fabricated lenses satisfied the basic physical properties of general hydrogel contact lenses and showed the characteristics of lenses with high water content, and the disadvantage of very weak durability, due to low tensile strength. However, it was confirmed that the tensile strength and antibacterial properties were greatly improved by adding GON and GNP. With GON, the oxygen permeability and refractive index of the fabricated lenses were slightly improved. Therefore, it was determined that the graphene materials used in this study can be used in various ways as a contact lens material.

목적: 상분리가 일어나지 않는 실리콘하이드로겔 콘택트렌즈(silicone hydrogel contact lens, SH-CL) 제조에 적합한 실리콘 모노머의 구조를 알아보고자 한다. 방법 : HEMA(2-hydroxyethyl methacrylate)와 세 종류의 실리콘 모노머, TRIM[3-(trimethoxysilyl)propyl methacrylate, Aldrich], TEMA[2-(trimethylsilyloxy)ethyl methacrylate, TCI], TMMA[(trimethylsilyl) methacrylate, Aldrich]를 활용하여 완전몰드로 SH-CL를 제조하였다. 함수율과 UV-VIS spectrophotomter 를 이용한 광투과율, TGA 분석을 통한 열적안정성 등의 물리적 특성과 FT-IR 분석을 통한 화학적 특성을 알아 보았다. 결과 : 동일한 양의 TRIM, TEMA, TMMA를 사용하여 제작한 SH-CL의 광투과율은 각각 92%, 86%, 80%로 측정되었으며, 함수율은 TRIM을 사용한 SH-CL에서 39.3%로 가장 높게 나타났다. FT-IR 분석 결과 세 종류의 SH-CL 모두 silicone monomer와 HEMA의 중합반응이 잘 이루어졌음을 확인할 수 있었고, TGA 분석을 통해 TRIM monomer의 sol-gel 반응 유무를 확인할 수 있었다. 결론 : Sol-gel 반응에 적합한 구조를 가지고 있어 상분리가 일어나지 않아 투명하고, Si에 극성 작용기인 methoxy기가 연결되어 있는 TRIM monomer가 SH-CL 제조에 적합한 구조임을 확인할 수 있었다.

In this study, lenses are fabricated using various nanomaterials as additives to a silicone polymer made with an optimum mixing ratio and short polymerization time. In addition, PVP is added at a ratio of 1% to investigate the physical properties according to the degree of dispersion, and the compatibility with hydrophobic silicone and the possibility of application as a functional lens material are confirmed. The main materials are SIU as a silicone monomer, DMA, a hydrophilic copolymer, EGDMA as a crosslinking agent, and 2H2M as a photoinitiator. Holmium (III) oxide, Europium (III) oxide, aluminum oxide, and PVP are used. When Holmium (III) oxide and Europium (III) oxide are added based on the Ref sample, the characteristics of the lens tend to be similar overall, and the aluminum oxide shows a tendency slightly different from the previous two oxides. This material can be used as a silicone lens material with various nano oxides and polyvinylpyrrolidone (PVP) acting as a dispersant.

This study uses silicone monomer, DMA, crosslinking agent EGDMA, and initiator AIBN as a basic combination to prepare hydrogel lenses using fluorine-based perfluoro polyether and iron oxide and zinc oxide nanoparticles as additives. After manufacturing the lens using iron oxide nanoparticles and zinc oxide nanoparticles, the optical, physical properties, and polymerization stability are evaluated to investigate the possibility of application as a functional hydrogel lens material. As a result of this experiment, it is found that the addition of the wetting material containing fluorine changes the surface energy of the produced hydrogel lens, thereby improving the wettability. Also, the addition of iron oxide and zinc oxide nanoparticles satisfies the basic hydrogel ophthalmic lens properties and slightly increases the UV blocking performance; it also increases the tensile strength by improving the durability of the hydrogel lens. The polymerization stability of the nanoparticles evaluated through the eluate test is found to be excellent. Therefore, it is judged that these materials can be used in various conditions as high functional hydrogel lens material.

목적 : 본 연구는 실리콘과 친수성 단량체를 포함하는 기능성 실리콘 콘택트렌즈를 제조하기 위해 Isobornyl Methacrylate 및 2-(Trifluoromethyl)styrene을 사용하여 물리적, 광학적 특성을 분석하였다. 방법 : 고분자의 중합은 실리콘 모노머와 친수성 단량체인 DMA(N,N-Dimethylacrylamide), 가교제인 EGDMA (Ethylene glycol dimethacrylate) 그리고 개시제인 AIBN(azobisisobutyronitrile)을 사용하여 공중합하였다. 첨 가제는 Isobornyl Methacrylate와 2-(Trifluoromethyl)styrene를 각각 사용하였으며, 제조된 콘택트렌즈의 물 성 변화를 알아보기 위해 분광투과율, 굴절률, 산소투과율, 인장강도 등을 측정하였다. 결과 : 제조된 친수성 콘택트렌즈의 산소투과율은 실리콘의 영향으로 33.22×10-11(cm2/s)(mlO2/ml×mmHg) 으로 나타났다. 첨가제인 Isobornyl Methacrylate의 양이 증가함에 따라 굴절률은 다소 향상되었고, 분광투과율은 첨 가제 양에 따라 가시광선 영역에서 약 15% 향상되어 투명한 콘택트렌즈가 제조되었다. 또한 2-(Trifluoromethyl) styrene의 첨가량에 따라 인장강도는 약 45% 향상된 것으로 나타났다. 결론 : 본 연구를 통해 제조된 실리콘 콘택트렌즈는 콘택트렌즈의 기본적인 물성을 만족시키면서 고산소투과성 을 가지며, Isobornyl Methacrylate 및 2-(Trifluoromethyl)styrene는 각각 상용성과 내구성을 향상시키는 것 으로 나타나 콘택트렌즈 재료로 다양하게 활용될 수 있을 것으로 판단된다.

n-Nonane, 1¸2¸4-trimethylbenzene (124-TMB), toluene, total xylene (TXYL), isopropyl alcohol (IPA), and methyl ethyl alcohol (MEK) are major volatile organic compounds (VOCs) emitted from printing industries. The absorption amount of a single VOC per unit weight of silicone oil was as follows in the order of 189.5 g/kg-silicone oil for n-nonane, 91.7 g/kg-silicone oil for 124-TMB, and 60.1 g/kg-silicone oil for TXYL. Although hydrophobic VOCs were more absorbed in silicone oil than hydrophilic VOCs such as IPA and MEK, IPA and MEK, which had log Kow values of 1 or less, also were absorbed more than 26.0 g/kg-silicone oil. In two and three mixed VOCs of n-nonane, 124-TMB, and toluene, the absorption amount of each in silicon oil was less than that of single a VOC. The total absorption amount of two mixed VOCs ranged from 47.9 g to 138.7 g/kg-silicone oil, and the total absorption amount of three mixed VOCs was 65.8 g/kg-silicone oil. These results suggest that silicone oil is a promising pretreatment solution capable of absorbing high concentrations of VOCs that are intermittently emitted from printing industries. The absorption information of VOCs obtained in this study can be used as the design parameters of a damping device for the pretreatment of VOCs.

This research is conducted to analyze the compatibility of used monomers and produce the high functional hydrogel ophthalmic polymer containing silane and nanoparticles. VTMS (vinyltrimethoxysilane), TAVS [Triacetoxy(vinyl)silane] and cobalt oxide nanoparticles are used as additives for the basic combination of SilM (silicone monomer), MMA (methyl methacrylate) and MA (methyl acrylate). Also, the materials are copolymerized with EGDMA (ethylene glycol dimethacrylate) as cross-linking agent, AIBN (thermal polymerization initiator) as the initiator. It is judged that the lenses of all combinations are optically excellent and thus have good compatibility. Measurement of the optical and physical characteristics of the manufactured hydrophilic ophthalmic polymer are different in each case. Especially for TAVS, the addition of cobalt oxide nanoparticles increases the oxygen permeability. These materials are considered to create synergy, so they can be used in functional hydrogel ophthalmic lenses.

목적 : 실리콘 하이드로겔렌즈의 베이스커브가 피팅상태와 착용감에 미치는 영향을 평가하고자 하였다. 방법 : 안질환이 없고 콘택트렌즈 착용에 문제가 없는 성인 30명(60안, 평균 나이: 21.9±1.5세)를 대상으로 하였다. 두 종류의 베이스커브(8.5 mm와 9.0 mm)를 가진 실리콘 하이드로겔렌즈를 사용하여 경험적 피팅법은 각막의 약주경선의 곡률반경이 7.8 mm보다 스티프하면 8.5 mm 베이스커브로, 7.8 mm보다 플랫하면 9.0 mm 베이스커브로 결정하였고, 시험렌즈 피팅법은 두 개 베이스커브의 콘택트렌즈를 이중맹검법으로 모두 착용 시킨 후 평가하였다. 콘택트렌즈 착용 후 피팅상태는 렌즈의 중심잡기, 순목 시 렌즈움직임, 래그(lag), 푸쉬업검사(push-up test), 케라토미터 마이어상 관찰 결과로 평가하였고, 자각적 착용감은 Likert 5점 척도 설문 조사를 통해 평가하였다. 결과 : 경험적 피팅법의 경우 전체 대상안의 91.67%에서 적합한 피팅상태를 보였으나, 시험렌즈 피팅법을 통해 두 가지 베이스커브의 피팅상태를 비교하면 스티프한 각막에 9.0 mm 베이스커브가 이상적인 경우가 33.33%, 플랫 한 각막에 8.5 mm 베이스커브가 이상적인 경우도 25%로 나타나, 경험적 피팅법을 통해 이상적인 성공률은 71.67% 을 나타냈고, 시험렌즈 피팅법은 100%의 성공률을 보였다. 베이스커브 별 착용감은 대상자의 63.33%가 베이스커 브에 따라 착용감에 차이를 느끼지 않았지만 8.5 mm에서 3.53점, 9.0 mm에서 2.75점으로 8.5 mm 베이스커브 에 대한 만족도가 유의하게 높았고(t=4.528, p<0.001), 플랫 각막군의 27.78%가 8.5 mm 베이스커브에 만족하는 것으로 나타났다. 결론 : 실리콘 하이드로겔렌즈의 베이스커브 선택에 있어서 각막의 곡률반경만을 고려한 경험적 피팅을 하거나 착용자 착용감에만 의존할 경우 부적합한 상태가 나타날 수 있으므로 시험렌즈 피팅을 통한 피팅상태 평가가 중요할 것으로 사료된다.

목적 : 재질이 다른 두 종류의 한달 착용 실리콘하이드로겔 렌즈를 착용 기간에 따라 렌즈 전면의 NITBUT와 자각적 증상을 비교하였다. 방법 : Samfilcon A와 Comfilcon A 렌즈를 32명(평균 23.5±2.92세, 여: 24명, 남: 8명)의 오른쪽 눈과 왼쪽 눈에 각각 착용하고, 대상자에게 3회 방문 (첫째 날 3시간 후, 1일 및 1주일 렌즈 착용 9시간 후)을 요청한 후, 고대비도(100%)와 저대비도(10%) 시력표를 이용한 시력검사와 Keratograph 5M (Oculus, Germany)을 사용하 여 렌즈 전면의 non-invasive tear breakup time (NITBUT)를 측정하였다. 콘택트렌즈와 관련 있는 자각적 증상은 5개 항목(불편함, 건조감, 시력 변화, 눈 감고 싶음, 렌즈 제거하고 싶음)으로 설문지 작성을 하도록 하였다. 결과 : 밝은 조명상태에서 검사한 고대비시력과 저대비시력, 그리고 렌즈 전면의 NITBUT는 Samfilcon A와 Comfilcon A 사이에서 유의한 차이가 나타나지 않았고, 각각의 렌즈 착용 7일 동안 시력과 NITBUT 변화에서도 의미 있는 차이는 없었다. 콘택트렌즈 착용과 관련된 5개 항목의 자각적 증상의 상대적 발생빈도는 모든 항목에서 유의한 차 이가 없었고, 렌즈에 대한 선호도에서도 두 렌즈 착용자들의 반응은 통계적으로 차이가 없었다(각각, 40.6%, 37.5%). 결론 : 이 연구는 Samfilcon A와 Comfilcon A사이에서 pre-lens NITBUT와 자각적 증상에 대한 비슷한 임상 결과를 보여준다. 두 실리콘하이드로겔 렌즈는 제조사와 렌즈 재질이 다름에도 불구하고 렌즈 착용자들 사이에 서 두 렌즈의 차이점은 발견할 수 없었다.

본 연구는 실리콘계 소포제가 해양으로 배출되었을 때 소포제 내에 존재하는 주요 성분들이 해양 저서환경에 서식하는 생물에게 미치는 영향을 알아보기 위해 실리콘 및 알코올계 소포제에 대해 저서성단각류(Monocorophium acherusicum)와 발광박테리아(Vibrio fischeri)를 이용하여 해양생태독성실험을 수행하였고 실리콘계 소포제의 주요성분인 디메틸폴리실록산(PDMS)에 대한 수중생물 독성영향을 조사하였다. 실리콘 및 알코올계 소포제에 대한 발광박테리아와 저서성단각류를 이용한 독성실험결과, 실험생물별 독성영향은 발광박테리아가 저서성 단각류에 비해 알코올계 소포제에서 최대 9배까지 민감한 독성영향을 보였으며 소포제 종류별 독성영향은 실리콘계 소포제가 알코올계 소포제에 비해 최대 400배 이상 높은 독성영향이 나타났다. 실리콘계 소포제의 주요성분인 PDMS가 수중생물에 미치는 영향을 조사한 결과, 식물플랑크톤, 무척추동물 및 어류에 대한 반수치사농도(LC50)및 반수영향농도(EC50)값은 10 ~ 44,500 μg/L의 범위로 나타났다. 물질의 정성적인 특성을 나타내는 지표인 PBT(P: persistency, B: bioaccumulation, T: toxicity)특성을 PDMS에 적용한 결과, 지속성(P)과 생물농축성(B)의 특성을 가지는 것으로 나타나 PDMS가 해양으로 배출될 경우 생물농축 및 먹이사슬을 통한 상위 영양단계로 축적될 가능성이 존재하며 저서생물에게 부정적인 영향을 미칠 수 있을 것으로 나타났다. 본 연구결과로 향후 실제 해양으로 배출되는 다양한 소포제가 해양생태계에 미치는 영향조사시 소포제 내 주요성분을 고려한 보다 객관적이고 과학적인 위해성평가에 기초자료로 활용될 수 있을 것으로 기대된다.

The water-swollen hydrogels containing silicone or fluorine were prepared by copolymerization of 2-hydroxy ethyl methacylate (HEMA) with 3-(trimethoxysilyl)propyl methacrylate(SM) or 2,2,2-trifluoroethyl acrylate(FA). When the content of SM or FA increased in copolymers, there was tendency of water absorbance to decrease, whereas contact angles to increase. The hydrogels containing FA showed 2 ~ 4% higher water content and 4 ~ 5% lower contact angles compared to that of SM. Tensile strengths decreased as the content of SM increased. However, FA exhibited strength of 2.2 Mpa/cm2 which is similar to 2.3 Mpa/cm2 of B. FA, which implies comparatively low adherence, hence, showed better protein resistance properties than SM-based hydrogel. The photo-polymerization was also applied instead of thermal polymerization to enhance the energy efficiency. As a result, the reaction yield reached over 95% within 1 minute.