Vinyl monomer에 의한 SIS block copolymer의 改質과 그 特性

왕은진,윤정식,유종선,백남철 慶熙大學校 材料科學技術硏究所 1991 材料科學技術硏究論集 Vol.4 No.-

The graft polymerization of 2-Hydroxyethylmethacrylate (HEMA) and Vinyltriethoxysilane (VTES) onto Styrene-isoprene-styrene block copolymer (SIS) was carried out in toluene, with radical initiators such as benzoyl peroxide(BPO) and α, α`-Azobisisobutyronitrile(AIBN) under nitrogen atmosphere. The degree of grafting was increased with the increases of the reaction temperature and reaction time. The efficiency of BPO was superior to that of AIBN. The mechanical properties and molecular weight of graft products were measured and the applicability as a adhesive of plasticized PVC leather was examined. The hardness and the molecular weight of graft products was increased with the increases of the degree of grafting, but elongation at break was decreased with the increases of one. And the tensile strength was maximum at the degree of grafting of about 6.5%. It was found that a toluene solution of graft products was confirmed to be an effective hot melt adhesive for the bond of plasticized PVC leather.

PDMS-PU 탄성체의 합성과 물성 및 Zwitterionization에 관한 연구

윤정욱,왕은진,백남철 慶熙大學校 材料科學技術硏究所 1992 材料科學技術硏究論集 Vol.5 No.-

The mechanical properties of polyurethane elastomer synthesized from hydroxybutyl-terminated polydimethylsiloxane(PDMS) of molecular weight 1000 and 4,4'-methylene diphenyldiisocyanate(MDI) were investigated. Hard segment content varied from 33% to 56% and various chain extender with 1,4-butanediol(BD), N-methyldiethanolamine(MDEA) or ethylene diamine(ED) were used in the segmented polyurethane block copolymer. The MDEA-extended materials were zwitterionized by using 1,3-propane sultone. By using gel permeation chromatography, infrared spectroscopy, differential scanning calorimetry and universal tensile Testing machine, physical and thermal properties of these polymers were investigated. All of these polyurethane elastomer showed phase separation. BD-extended material shows a higher tensile strength for the higher hard segment content material. MDEA-extended materials which were ionized by 1,3-PS exhibited better tensile properties than un-ionized copolymer. The zwitterionomer material exhibited ionic aggregation within the hard domain. Hard domain cohesion was found to be a important factor in determining the tensile properties of the elastomers.

스티렌 - 부타디엔 - 스티렌 블록 공중합체의 개질과 그 특성

유종선,백남철,윤정식,왕은진 한국고무학회 1990 엘라스토머 및 콤포지트 Vol.25 No.4

The graft polymerization of 2-hydroxyethylmethacrylate(HEMA) and vinyltriethoxysilane(VTES) onto styrene-butadiene-styrene block copolymer(SBS) was carried out in toluene, with radical initiator such as benzoyl peroxide(BPO) and 2, 2'-azo-bis-isobutyronitrile(AIBIN) under nitrogen atmosphere. The degree of grafting was increased with the increases of the reaction temperature and time. And the effeciency of BPO was superior to that of AIBN. The mechanical properties and molecular weight of graft products were measured and the applicability as adhesive of plasticized PVC leather was examined.

보문 : 국내 아까시나무 숲에서 수집한 감자덩이버섯 (Mattirolomyces terfezioides)의 균사 생장 특성과 효소 활성

전성민 ( Sungmin Jeon ),왕은진 ( Eunjin Wang ),가강현 ( Kanghyeon Ka ) 한국균학회 2015 韓國菌學會誌 Vol.43 No.3

감자덩이버섯(Mattirolomyces terfezioides)은 단맛을 가진 트러플의 한 종류로, 주로 아까시나무(Robinia pseudoacacia) 와 외생균근을 형성한다. 상업적으로 인공재배할 만한가치가 있는 버섯으로, 본 연구에서는 우리나라 아까시나무 숲에서 수집한 감자덩이버섯균의 균사 생장특성과 효소 활성에 대해 조사한 바를 처음으로 보고하고자 한다. 이 균은 PDA 배지, 30oC에서 가장 잘 생장하였고, 액체배양 시에는 pH 8.0의 MMN 배지에서 균 생장력이 가장 우수하였다. 또한 암모늄염보다는 질산염 형태의 무기질소원이 함유된 액체배지에서 균체량이 1.8배 더 높았으며, 효소 검색용 고체배지 상에서 carboxymethylcellase와 laccase 활성을 나타냈다. Mattirolomyces terfezioides is a type of sweet truffles that predominantly form ectomycorrhizae with Robinia pseudoacacia. It is also worthy of artificial cultivation. This is the first report on characteristics of mycelial growth and enzyme activities of M. terfezioides collected from R. pseudoacacia forest in Korea. M. terfezioides showed the highest mycelial growth when cultured on potato dextrose agar (PDA) at 30oC or in modified Melin-Norkran’s liquid medium (pH 8.0). The biomass of M. terfezioides was higher in liquid medium containing nitrate-nitrogen than ammonium-nitrogen by 1.8 fold. The mycelia of M. terfezioides showed both carboxymethylcellulase and laccase activities on solid media for enzyme screening.

한국에 자생하는 녹청균류의 기초 배양 특성

전성민 ( Sung-min Jeon ),가강현 ( Kang-hyeon Ka ),왕은진 ( Eun-jin Wang ),유림 ( Rhim Ryoo ),장영선 ( Yeongseon Jang ) 한국균학회 2018 韓國菌學會誌 Vol.46 No.2

Members of Chlorociboria are soft-rot ascomycetes that produce blue-green pigment. We investigated the growth characteristics of two Korean species of Chlorociboria, eight strains of Chlorociboria aeruginascens and Chlorociboria poutoensis, under various culture conditions (solid media, temperature, pH) and screened them for extracellular enzyme activity. Although the growth rate was slow, all tested strains of Chlorociboria spp. grew well on potato dextrose agar (PDA; 16.3~42.6 mm after 60 days) or Sabouraud dextrose agar (SDA), but not on malt extract agar (MEA). Compared with C. aeruginascens strains, C. poutoensis strains exhibited higher expression of blue-green pigments on both PDA and SDA media. The optimal temperature for mycelial growth was 20~25°C, and mycelial growth was lower at 30°C than at 10°C. All strains tended to have increased mycelial growth as the incubation temperature increased in the range of 10 to 20°C. The optimal pH of potato dextrose broth (PDB) for mycelial growth varied according to the strain under static culture conditions. Maximum biomass production was obtained at pH 6.0 for NIFoS 579 (114.3 ± 5.1 mg/60 days), but it maintained a stable pigment expression under a broad pH spectrum. The activities of both cellulase and laccase were observed in all tested strains of Chlorociboria spp. Enzyme activities of NIFoS 579 were remarkably higher than those of the other strains. From these results, we suggest that C. poutoensis NIFoS 579 is a potential candidate for use as a source of natural blue-green dye.

송이 감염묘 육성을 위해 야외 조건에서도 송이균 생존이 가능한 소나무의 최소 크기 결정

가강현 ( Kang-hyeon Ka ),김희수 ( Hee-su Kim ),전성민 ( Sung-min Jeon ),유림 ( Rhim Ryoo ),장영선 ( Yeongsun Jang ),왕은진 ( Eun-jin Wang ),정연석 ( Yeun Sug Jeong ) 한국균학회 2017 韓國菌學會誌 Vol.45 No.3

Despite the high commercial value of the pine mushroom (Tricholoma matsutake) around the world, its production still depends upon natural harvesting. In recent years, mushroom researchers in Korea and Japan have been successful in artificially cultivating T. matsutake by producing single mushroom through matsutake-infected pine seedlings. In this study, we determined the minimum seedling height required for the survival of matsutake mycelia in the infected pine seedlings in the field. The survival rate of matsutake mycelia in the matsutakeinfected pine seedlings was 50% (14) in two years and 71% (10) in one year after their transplantation. The average height at time of transplantation of the matsutake-infected pine seedlings that bore surviving mycelia after transplantation was 25 cm (minimum 12 cm to maximum 40 cm). In conclusion, the matsutake mycelium of matsutake-infected pine seedlings was able to survive in field conditions if the height of the seedling at the time of T. matsutake infection was at least 12 cm. These results suggest that the height of the host plants used in conventional matsutake-infected pine seedling production should be greatly reduced to improve the matsutake cultivation. Therefore, standardization of the seedling height for artificial cultivation of pine mushrooms by the matsutake-infected pine seedling method is suggested.