높은 char 수득률을 갖는 방향족 polybenzoxazoles의 제조 및 특성

손준연 ( Jun Youn Sohn ),문성철 ( Sung Chul Moon ),윤두수 ( Doo Soo Yoon ),최재곤 ( Jae Kon Choi ) 한국고무학회 2007 엘라스토머 및 콤포지트 Vol.42 No.4

일련의 방향족 polyhydroxyamides(PHA)를 저온 용액 중축합으로 합성하였다. 이들 중합체들은 FT-IR, 1H-NMR, DSC, TGA 그리고 PCFC를 이용하여 특성들을 조사하였다. PHA 중합체들의 고유점성도는 DMAc 용매 하에 35℃에서 0.5~1.1 dL/g의 값을 나타내었다. PHA 3을 제외한 중합체들은 N,N-dimethylacetamide(DMAc), N-methyl-2-pyrrolidone(NMP), N,N-dimethylformamide(DMF) 등과 같은 극성 유기 용매에 용해되었지만, 열적 고리화 반응에 의해 전환된 polybenzoxazoles(PBOs)는 용해되지 않았다. PBO 3을 제외한 PBO 중합체들에서는 DSC에서 200~246℃의 유리전이온도(Tg)를 보였고, TGA에서의 최대분해온도는 질소 분위기 하에서 597~697℃의 범위를 보였다. PBO 중합체들은 51-64%의 높은 차 수득률을 보였다. PCFC에서 PBOs의 heat release(HR) capacity는 8~65 J/gK의 값을 보였고, total heat release(total HR)의 값은 2.4~4.7 kJ/g을 보였다. A series of polyhydroxyamides(PHAs) having ether linkages in the polymer backbone were prepared via solution polycondensation at low temperature. These polymers were studied by FT-IR, 1H-NMR, DSC, TGA and PCFC. The PHAs exhibited inherent viscosities in the range of 0.5~1.1 dL/g at 35℃ in DMAc solution. Most of PHAs except PHA 3 were soluble in polar organic solvents such as N,N-dimethylacetamide(DMAc), N-methyl-2-pyrrolidone(NMP), and N,N-dimethylform-amide(DMF). Subsequent thermal treatment of PHAs afforded polybenzoxazols(PBOs). However, the PBOs were insoluble in a variety of solvents. Most of the PBOs except PBO 3 showed glass-transition temperature(Tg) in the range of 200~246℃ by DSC and maximum weight loss temperature in the range of 597~697℃ in nitrogen by TGA. PBOs showed high char yields in the range of 51-64%. PCFC results of the PBOs showed the heat release(HR) capacity, 8~65 J/gK and total heat release(total HR), 2.4~4.7 kJ/g.

수용액에서 수정된 항암 전구약물과 단백질 간의 상호작용

손준연 ( Jun-youn Sohn ),손정선 ( Jeong-sun Sohn ) 조선대학교 공학기술연구원 2017 공학기술논문지 Vol.10 No.1

We have investigated the interaction of a new water-soluble paclitaxel (7-mPEG5,000-succinyloxymethyloxycarbonyl-paclitaxel, PP7) and hen egg albumin (Mr ~45,000) by pulse-gradient field NMR (PFG-NMR). Diffusion coefficient of PP7 with Albumin in modified Hank`s Balanced Salt Solution (MHBSS) was measured as a function of PP7 (0.0~1.7% w/w) and albumin (0.0~1.4% w/w) concentration at different temperatures. This study suggested that the results of molecular mobility and interaction can be used to determine the transport mechanisms in human body liquid.

화학적환원에 의한 DNA-mediated 금 나노입자의 합성 및 특성

손준연 ( Jun Youn Sohn ),손정선 ( Jeong Sun Sohn ) 한국공업화학회 2015 공업화학 Vol.26 No.4

Complexes composed of hydrogen tetrachloroaurate (3) trihydrate (HAuCl4·3H2O) and DNA were first formed for the synthesis of gold nanoparticle using a DNA template, which were validated using UV-Vis spectroscopy. The morphology of complexes were also characterized by scanning electron microscopy (SEM). DNA-mediated gold nanoparticles were synthesized by the chemical reduction of DNA-Au(3) complexes using hydrazine (N2H4) and sodium borohydride (NaBH4) as reducing agents. The effects of reducing agent types and their concentration on the formation of gold nanoparticles were investigated. The results showed that hydarazine was the most effective for the reduction of DNA-Au(3) complex. The DNA-mediated gold nanoparticles were characterized SEM, particle size analyzer (PSA), and transmission electron microscopy (TEM). Gold nanoparticles with 55~80 nm in diameter were formed by the aggregation of smaller gold nanoparticles ( ∼nm), which was confirmed in the DNA matrix.

버섯류-마늘 혼합추출물이 생리활성 및 면역 증가에 미치는 영향

손준연 ( Jun Youn Sohn ),나행요 ( Haeng Yo Na ),손정선 ( Jeong Sun Sohn ) 한국산업식품공학회 2021 산업 식품공학 Vol.25 No.4

As the world becomes an aging society, various geriatric diseases are induced, posing a tremendous social burden. For the development of healthy food, mushrooms and garlic, which are natural medicinal resource materials, and their mixed extracts were prepared, while the contents of general components, β-glucan, free sugar, and organic acid, were confirmed. In the case of garlic, the contents of alline and heavy metals were confirmed. The presence or absence of toxicity in each sample was checked through MTT assay in vitro, while the appropriate treatment concentration was established to confirm each extract's immune activation and anticancer effects. As a result of examining the anticancer effect from the thymus and lymph node cells of experimental mice administered orally, each extract in vivo confirmed that the CD4 T cells of thymocytes and lymph node cells were increased at all concentrations of the mixed two extracts, and they exhibit immunity activation and anticancer properties.

PVA 바인더를 이용한 고형환원제 제조 및 특성연구

정호영(Ho Young Jung),손준연(Jun Youn Sohn),노선균(Sun Gyun Roh),임민화(Min Hwa Lim),손정선(Jeong Sun Sohn) 한국고분자학회 2019 폴리머 Vol.43 No.3

본 연구에서는 불화수소(HF) 제거를 위한 구형 다공성 복합구조체인 고형환원제를 제조하였다. 먼저 지지체로 SiO₂와 Ca(OH)₂를 도입하여 CaO/SiO₂ 혼합물을 제조한 후, 바인더로 다양한 분자량을 갖는 폴리(비닐 알코올) (PVA)을 이용하여 여러 가지 조성으로 고형환원제를 제조하고 이들의 조성에 따른 열적특성, 모폴로지, 압축강도, 비표면적특성 및 기공특성을 조사하였다. CaO의 농도가 60 wt%인 혼합물에 바인더로 중량평균분자량이 31000~50000인 PVA를 2 wt% 사용한 고형환원제(60-2PVA50K)의 경우 압축강도, 비표면적 및 기공도가 최적화되는 것을 확인하였다. 바인더의 도입은 고형환원제가 분말화되는 것을 억제하면서 비표면적을 크게 하여 흡착특성을 향상시킬 수 있을 것으로 기대된다. In this study, a solid reducing agent, a spherical porous composite structure for hydrogen fluoride (HF) removal, was prepared. First, SiO₂ as a support and Ca(OH)₂ were introduced to prepare a CaO/SiO₂ mixture, and poly(vinyl alcohol) (PVA) having various molecular weights was used as a binder to prepare solid reducing agents having various compositions. Thermal properties, morphology, compressive strength, specific surface area, and pore characteristics were investigated according to their compositions. The optimized compressive strength, the specific surface area and porosity were observed for the solid reducing agent (60-2PVA50K) using 2 wt% of PVA having a weight average molecular weight of 31000 to 50000 as a binder in a mixture having a CaO concentration of 60 wt%. The introduction of the binder is expected to increase the specific surface area and improve the adsorption characteristics while suppressing the formation of powder of the solid reducing agent.

방향족 poly(hydroxyamide)s의 합성 및 열적 특성

손준연,최재곤 조선대학교 생산기술연구소 2006 生産技術硏究 Vol.28 No.2

A sereis of polyhydroxyamides(PHAs), having ether linkages in the polymer backbone were prepared via solution polycondensation at low tmperature. The PHAs exhibited inherent viscosities in the range of 0.5-1.1 dL/g at 35℃ in DMAc solution. These PHAs were studies by FT-IR, ^(1)H-NMR, DSC, TGA and XRD. All polymers were soluble in polar organic solvents. Subsequent thermal treatment of the PHAs afforded polybenzoxazols(PBOs). However, the PBOs were nearly insoluble in variety of organic solvents. All PBOs showed glass-transition temperatures(T_(g)) in the range of 202-255 ℃ by DSC and maximum weight loss temperatures in the range of 588-603 ℃ in nitrogen by TGA.

폴리벤즈옥사졸 전구체의 합성 및 특성

한철,손준연,김희선,윤두수,최재곤 조선대학교 생산기술연구소 2007 生産技術硏究 Vol.29 No.1

Polyhydroxyamides(PHAs) having ether linkages in the polymer backbone were synthesized by solution polycondensation at low tmperature. The PHAs were studies by FT-IR, ^(1)H-NMR, DSC, and TGA. The inherent viscosities of the PHAs showed in the range of 0.5-1.1 dL/g at 35℃ in DMAc solution. Solubility of the PHAs were soluble in DMAc, DMF, DMSO, NMP, and pyhdine, but the PBOs were nearly insoluble in a variety of solvents. PHAs were converted to polybenzoxazoles(PBOs) by thermal cyclization reaction with heat of endotherm. The degradation temperatures of the polymers were recorded in the ranges of 591-683℃ in N₂.