• Nuclear Engineering and Technology
• /
• 제4권2호
• /
• pp.90-101
• /
• 1972

Polyester 직포 표면을 친수화하기 위하여 함침법에 의하여 acrylic acid를 방사선 graft 공중합시켰다. 이때 함침된 직포를 질소에서 Co-60감마선으로 조사하였다. 생성된 Homopolymer는 10$0^{\circ}C$의 물에 의하여 대체로 유출되었다. Graft된 직포는 산성, 염기성 또는 분산염료에 대하여 재래식 저온 침염법에 의해서 염색이 잘 되었다.

• 한국염색가공학회지
• /
• 제1권1호
• /
• pp.7-18
• /
• 1989

The distinguishing characteristic of the glow discharge is that chemical reaction induced by partially ionized gases are limited only to the substrate surface. Most studies have been done on the plasma etching and polymerization. The graft polymerization in vapour phase by cold plasma has been rarely investigated. In this study the system of tub3ar reaction chamber with capacitively coupled electrode of alternative current of 60 Hz was employed for the graft polymerization. The graft polymerization of Acylic Acid(AA) onto the poly (ethylene terephthalate) (PET) was carried out by treatment of PET film and fabric by cold plasma (glow discharge of argon gas), followed by the supply of AA vapour. The graft yield was about 1 wt%. The surface property was determined by contact angle, the surface tension was evaluated by zisman’s plot and equation of surface tension mesurement. The results were as follows: 1. In order to obtain lower contact angle, it was effective to avoid the vicinity of electrodes for a setting position of substrate. 2. Contact angle affected on the monomer pressure and its duration of exposure to the acid vapour. 3. Polymer radical formation was influenced by the changes of the value of current density and plasma treatment time. 4. Total surface tension of plasma grafted PET film increased. With an increase in the carboxylic acid content, the dispersion force decreased, while, the polar force and hydrogen bonding force increased. 5. The contact angle decreased from $75^\circ$ to around $30^\circ$ by plasma grafting. There was no ageing effect on the contact angle after 4 months.

• Archives of Plastic Surgery
• /
• 제34권3호
• /
• pp.279-284
• /
• 2007

Purpose: The vein graft was considered as a useful conduit for nerve defect. But the problem is that it might be collapsed in long vein graft state. A new experimental model using vein graft filled with hyaluronic acid was considered. Methods: Thirty rats were used for the experimental animal. In group I, one side of the femoral nerve was exposed and a segment was removed about 15mm. The neural gap was connected with nerve graft. In group II, the nerve gap was connected with vein graft only. In group III, the nerve gap was connected with vein graft filled with hyaluronic acid. A walking track analysis was made periodically for 2 months and NCV(nerve conduction velocity) was executed at the end of the experiment. And morphologic studies were also done for all groups Results: In a walking track analysis, the toe-spread was widen and the foot-length was lengthened. The recovery of the toe-spread and foot length was checked 2 weeks interval, periodically for two months. The SFI (sciatic function index) was $-52.5{\pm}8.2$ in group I, $-68.1{\pm}4$ in group II, $-55.3{\pm}7.9$ in group III. In electrophysiological study, NCV(nerve conduction velocity) was $26.71{\pm}3.11m/s$ in group I, $17.94{\pm}4.35m/s$ in group II, $25.69{\pm}2.81m/s$ in group III. The functional recovery in group I and III was superior to that the group II statistically(p < 0.05) Under electromicroscopic study, the number of the myelinated axons were $1419.1{\pm}240$ in group I, $921.7{\pm}176.8$ in group II, $1322.2{\pm}318$ in group III. The number of the myelinated axons were much more in group I and III than group II statistically (p<0.05). Conclusion: This study suggested that the vein graft filled with hyaluronic acid is more effective than vein graft only for the conduit of the nerve gap. It was thought that the technique could be used in clinical cases with nerve defects as an alternative method to classical nerve grafts.

• 폴리머
• /
• 제32권6호
• /
• pp.561-565
• /
• 2008

본 연구에서는 천연고분자인 히알루론산(hyaluronic acid, HA)에 항산화제인 리포산(lipoic acid, LA)을 그래프트시켜 양친성 공중합체를 결합하였다. 이 공중합체는 수용액상에서 자기조립에 의해서 친수성인 히알루론산이 소수성인 리포산을 감싸는 형태의 고분자 입자를 형성한다. 히알루론간과 리포산을 결합하기 전에 adipic acid dihydrazide(ADH)을 이용하여 히알루론산의 카복실 부분을 개질시켰다. 히알루론산의 개질 분석과 HA-g-LA의 결합을 확인하기 위해 분광학적 분석방법을 이용하여 분석하였다. 형성된 입자는 DLS와 TEM을 사용하여 크기를 측정하였고 나노크기의 구조를 이룬다는 것을 확인하였다. 나노크기의 고분자 입자는 소수성 물질을 포함하는 전달체로 사용될 수 있다.

• 폴리머
• /
• 제34권2호
• /
• pp.150-153
• /
• 2010

본 연구에서는 방사선에 의한 그래프트 중합을 이용하여 생체분자가 고정화된 다중벽탄소나노튜브 (MWCNT)를 제조하였다. 생체분자의 고정화를 위하여 MWCNT에 아크릴 산을 그래프트 중합하였다. 열중량분석과 라만 분석을 통하여 MWCNT에 폴리(아크릴 산)이 효과적으로 그래프트 중합되었음을 확인하였다. 폴리(아크릴 산)이 그래프트 된 MWCNT에 DNA와 단백질과 같은 생체분자들을 고정화하였다. X-선 광전자 분광법과 형광분석을 통하여 생체분자들이 성공적으로 MWCNT에 도입되었음이 확인되었다.

• 폴리머
• /
• 제24권5호
• /
• pp.621-628
• /
• 2000

폴리프로필렌 다공성 분리막은 산, 알칼리에 대한 내화학성이 좋고, 기계적 성질이 우수하며 높은 열적 안정성을 가지고 있으나, 막의 소수성 때문에 일부 영역에만 사용이 제한되고 있다. 따라서 본 연구에서는 소수성 막의 성능을 향상시키기 위해서 방사선 조사에 의한 그라프트 중합법을 사용하여, 친수성 작용기 (-COOH, -OH)를 갖는 acrylic acid (AAc)와 2-hydroxyethyl methacrylate (MEMA)를 도입하였다. 이때 반응시간, 반응온도, 조사량, 간의 첨가 효과, 팽윤현상에 의한 그라프트율의 변화를 조사하였다. 분리막의 기공크기를 분석하는 방법으로 행한 가스투과 실험에서 단량체의 종류와 관계없이 그라프트가 증가함에 따라 가스 투과속도가 감소함을 보였고, 오일 에멀젼 투과실험에서 미개질 폴리프로필렌 막의 오염현상은 크게 발생하였으나, 그라프트 중합 후, 높은 투과속도를 유지하여 막의 친수화 효과가 큰 것으로 나타났다.

• 한국의류학회지
• /
• 제17권3호
• /
• pp.347-358
• /
• 1993

Graft copolymerization of MMN4-VP onto cotton fiber using Ce(IV) salt as an initiator and triton X-100 as an emulsifier was performed under various polymerization conditions. In cograft polymerization, the polymeization behavior according to variation of 4-VP feed composition and the characteristics of MMA/4-VP graft polymer such as affinity for acid dye owing to cationization of cotton, antibacterial activity and thermal behavior were investigated. The results of this study were as follows : 1. While in copolymerization of MMA and 4-VP, 4-VP content in copolymer was more than that of monomer feed composition. 2. Increasing 4-VP content, graft yield was decreased, but graft efficiency was increased. In case of MMA/4-VP graft polymerization, the highest graft yield was obtained at higher CAN concentration than in MMA graft polymerization, the reason is that the behavior of 4-VP was disturbed by Ce(IV) sail 3. Elevation of temperature resulted in increase of graft yield and the apparent activation energy of MMA/4-VP graft polymerization was higher than that of MMA graft polymerization. 4. MMA/4-VP grafted cotton fiber showed affinity for acid dye, antibacterial activity and higher moisture regain than MMA grafted cotton fiber. MMA/4-VP grafted cotton fabric showed improvement of wrinkle recovery up to 40~50% graft yield and decreased thereafter. MMA/4-VP and MMA grafted cotton fabric did not showed significant difference in wrinkle recovery and stiffness.

• Nuclear Engineering and Technology
• /
• 제6권3호
• /
• pp.161-169
• /
• 1974

Nylon직포의 표면을 친수화 하기 위하여 동시조사법으로 Acrylic acid를 방사선 graft중합시켰다. Monomer용액속서 침지된 Nylon직포를 공기중 또는 진공하에서 ${\gamma}$-선으로 조사시켰다. 직포 표면에 형성된 Polyacrylic acid는 10$0^{\circ}C$의 sodium hydroxide용액(0.1%)으로 대부분 추출되었다. 접목 반응된 생성물의 화학적 조성을 측정하였다. 접목반응된 Polymer와 방사선 처리를 하지 않은 polyamide를 비교하여 볼 때 흡수성이라든가 대전성은 증진되었다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제28권3호
• /
• pp.205-215
• /
• 2002

The purpose of this study was to evaluate the tissue response in various bone grafting materials, especially xenogenous bone materials in vivo, compare of bone formation capacity of various bone grafting materials on rat skull defects and evaluate the effect of Hyaluronic acid on healing of human Demineralized Freezed Dried Bone allogenous graft (DFDBA) materials in rat calvarial defects. 30 Sprague-Dawly rats were divided into 4 groups. $7{\times}7mm$ size bony defect were artificially prepared in the calvaria (both parietal bone) of all 30 rats and follwed group grafting of autogenous bone graft on right side and allogenic DFDBA on left side bone graft (rat DFDB) in 15 control group, but in 15 experimental group, xenograft (human DFDB) on left side, hyaluronic acid treated with xenograft on right side. Sequential sacrifices was performed at 1, 2, 4, 6, 8 weeks of experiment. These specimens were stained with H&E and MT stain, and then histologic analysis under light microscope was carried out. There were inflammatory reaction in all graft material during early stage. Autogenous and Allogenous DFDBA graft group observed inflammatory reaction at 1 week. Xenograft group persistant inflammatory reaction until 4 weeks, but in HA treated xenograft group inflammatory reaction was decreased at 2 weeks. Osteoblastic activity in control group was begun at 2 week, xenograft group was delayed at 6 weeks, however HA treated xenograft group was begun at 4 weeks. At 2 week, mild osteoclastic activity were observed in all xenograft group not in concerned to HA, but there was no difference each group after 4 weeks. There are most activated angiogenesis around graft mateirals in xenograft group at 2 weeks, but in HA treated xenograft group, decreased angiogenesis was observed at same time. Bone formation and bone maturation of xenograft group, there was no difference in HA treatment, was less than control group. Fibrosis around xenograft materials were observed until 6 weeks, there was no difference between xenograft and HA treated groups.

• 한국잠사곤충학회지
• /
• 제20권2호
• /
• pp.40-44
• /
• 1978

1. 개시제농도에 따른 graft 율의 변화를 보면 CAN농도가 0.003M 일 때 최대를 나타내었다. 2. 단량체농도가 증가함에 따라 graft 율이 상승함을 보였다. 3. HNO$_3$농도 0.lM 부근에 서 graft 율의 최대가 인정되었다. 4. 반응온도가 높아짐에 따라 graft 율이 상승하나 5$0^{\circ}C$ 이상이 되면 homopolymer 의 생성이 많아 비 효율적이다. 5. 중합시간이 1 시간 이상이 되면 graft 율이 급격히 상승함을 보이고 있다. 6. CAN 의 농도가 작을수록 연감율이 작게 나타났다. 7. graft 율이 20% 이상이 되면 sericin 이 대부분 정착되었다.