• 폴리머
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• 제24권1호
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• pp.128-132
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• 2000

Polycaprolactone (PCL) 블록의 함량이 62.7 wt%인 PCL-폴리아미드 블록공중합체와 poly(vinyl chloride) (PVC)의 상용거동을 시차주사열량계로 열적 성질을 관찰하여 조사하고, 블렌드물의 인장물성을 측정하였다. PCL과 PVC 세그먼트는 상용성을 가졌으며, PVC의 함량이 많은 경우 PCL의 결정화가 방해받아 PCL과 PVC 세그먼트로 구성된 비결정성 균일상이 형성됨을 알 수 있었다. PCL/PVC 균일 비결정상과 폴리아미드의 결정상이 병존하는 경우 균일 비결정상의 유리전이온도와 결정상의 녹는점 사이의 온도 영역에서 블렌드물은 고무탄성을 가졌다.

• 한국추진공학회지
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• 제2권3호
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• pp.62-69
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• 1998

Polycaprolactone (PCP)과 coupling agent로 silane 유도체를 polyethylene glycol(PEG)/cyclo-tetramethylene tetranitramine(HMX) 추진제에 첨가하였을 때 추진제의 기계적 특성 변화를 연구하였다. PEG의 일부를 Polycaprolactone(PCP)으로 대체 사용하면 추진제의 기계적 성질은 증가하였으며, PCP/HMX 추진제는 PEG/HMX보다 최대 인장 강도가 17%, 최대 응력하의 신율은 59% 증가하였다. 그러나 PCP함량이 증가할수록 수분에 대한 안정성은 저하됨을 $40^{\cire}C$의 온도와 90% 상대 습도 분위기에서 보관된 추진제의 경도 변화와 PEG/PCP바인더의 부피 팽윤 실험에 의해 알 수 있었다. 또한 PEG/PCP/HMX 추진제를 $60^{\cire}C$에서 가속 노화시키면 triethoxysilyl propionitrile(TESPN)과dinitrosalicylic acid((DNSA) 함량이 증가할수록 추진제의 경도가 감소하는 것으로 나타났다.

• 환경생물
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• 제22권3호
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• pp.400-404
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• 2004

유기합성적으로 제조된 지방족 폴리에스테르의 일종인 polycaprolactone (PCL)을 $27^\circ{C}$와 $37^\circ{C}$로 온도를 달리한 활성오니토양에 66일간 매립하여 토양미생물에 의해 분해된 PCL 필름의 표면변화를 관찰하고, PCL을 분해하는 토양진균과 토양세균을 분리, 동정하였다. PCL을 탄소원과 에너지원으로 이용하는 토양진균으로는 Paecilomyces fumosoroseus KH27, Penicillium digitatum KH28, Fusarium solani KH29와 Aspergillus sp. KH30, 토양세균으로는 Ochrobactrum anthropi KH3l이 분리되었다. $27^\circ{C}$에서는 P. digitatum KH28이 가장 높은 PCL 분해능(46%)을 보였고, $37^\circ{C}$에서는 O. anthropi KH31의 분해능(52%)이 가장 우수하였다.

• Bulletin of the Korean Chemical Society
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• 제32권1호
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• pp.157-161
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• 2011

For the fabrication of multifunctional biopolymer nanocomposites in the combination of carbon nanotubes (CNTs), recently increasing attention has been paid to an effective homogenization of CNTs within polymer matrices and a fine tuning of the concentration. We developed an efficient method to produce homogeneous CNT-polycaprolactone nanocomposites with various and controllable CNT concentrations using an ionically-modified multi-walled CNT, MWCNT-Cl. The modified MWCNTs could be homogeneously dispersed in tetrahydrofuran (THF). Polycaprolactone (PCL) as a biodegradable and biocompatible polymer was smoothly dissolved in the homogeneous MWCNT-Cl/THF solution without agglomeration of MWCNT-Cl. The physicochemical and mechanical properties of the resultant nanocomposites were examined and the biological usefulness was briefly assessed.

• Archives of Plastic Surgery
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• 제49권6호
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• pp.740-744
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• 2022

Titanium mesh is an alloplastic material widely used for the reconstruction of moderate-to-large skull defects. Repeated wound problems or infection following these reconstructions inevitably lead to the replacement of the cranioplasty material. Among the various alloplastic materials, polycaprolactone implants are usually used for the coverage of small defects such as burr holes. Herein, we present a case of a large cranial defect successfully reconstructed with three-dimensional-printed polycaprolactone implant and a free latissimus dorsi musculocutaneous flap. Until 1-year followup, the patient showed a favorable esthetic outcome with no complications or wound relapse.

• 폴리머
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• 제29권4호
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• pp.344-349
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• 2005

분자량이 다른 여러 종류의 폴리카프로락톤 디올(polycaprolactone diol), 폴리카프로락톤 트리올(polycaprolactone triol), acetylbutyl citrate 가소제, isophorone diisocyanate 경화제를 이용하여 폴리우레탄을 합성하였다. 합성된 폴리우레탄의 구조를 FT-IR, NMR 스펙트럼 분석을 통하여 확인하였고 TGA와 UTM을 이용하여 열특성 및 인장강도 연신율을 측정하였다. Compressive modulus를 사용하여 측정한 결과, 합성한 폴리우레탄의 가교 평균 분자량은 $8000\~24000$이었다. 분자 내 가교밀도 및 하드 세그먼트의 양이 증가할수록 인장강도가 증가하고 연신율이 감소하였으며, 폴리우레탄내의 가교밀도가 증가할수록 열 안정성이 향상되었다. 가교밀도는 NCO/OH의 비가 1.1에서 최대값을 나타내었고, 디올의 함량과 분자량이 클수록 증가하였다.

• Korean Chemical Engineering Research
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• 제53권2호
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• pp.193-198
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• 2015

Polycaprolactone, Dichloromethane, 이산화탄소로 구성된 3성분계 고압 시스템의 상거동 측정 실험은 가변 부피 셀 장치를 이용해서 측정했다. 실험의 온도범위는 313.15 K에서 353.15 K, 압력은 약 300 bar까지 측정했으며 실험결과는 Polycaprolactone의 질량 분율이 1.0%, 2.0%, 3.0%일 때 온도와 이산화탄소/Dichloromethane의 질량 분율로 정리했다. 또한 실험 결과는 hybrid 상태방정식 (Peng-Robinson 상태방정식과 SAFT 상태방정식의 혼합형태) 을 이용하여 열역학적으로 검증하였으며, 혼합규칙은 반데르 발스의 단일 유체 혼합규칙을 사용했다. 이 다성분계 시스템에서 이원 상호 작용 파라미터 등, 각종 파라미터는 심플렉스 알고리즘을 통해 최적화했다.

• Archives of Plastic Surgery
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• 제46권5호
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• pp.399-404
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• 2019

Background The objectives of this study were to design polycaprolactone nanofibers with a radial pattern using a modified electrospinning method and to evaluate the effect of radial nanofiber deposition on mechanical and biological properties compared to non-patterned samples. Methods Radially patterned polycaprolactone nanofibers were prepared with a modified electrospinning method and compared with randomly deposited nanofibers. The surface morphology of samples was observed under scanning electron microscopy (SEM). The tensile properties of nanofibrous mats were measured using a tabletop uniaxial testing machine. Fluorescence-stained human bone marrow stem cells were placed along the perimeter of the radially patterned and randomly deposited. Their migration toward the center was observed on days 1, 4, and 7, and quantitatively measured using ImageJ software. Results Overall, there were no statistically significant differences in mechanical properties between the two types of polycaprolactone nanofibrous mats. SEM images of the obtained samples suggested that the directionality of the nanofibers was toward the central area, regardless of where the nanofibers were located throughout the entire sample. Florescence images showed stronger fluorescence inside the circle in radially aligned nanofibers, with significant differences on days 4 and 7, indicating that migration was quicker along radially aligned nanofibers than along randomly deposited nanofibers. Conclusions In this study, we successfully used modified electrospinning to fabricate radially aligned nanofibers with similar mechanical properties to those of conventional randomly aligned nanofibers. In addition, we observed faster migration along radially aligned nanofibers than along randomly deposited nanofibers. Collectively, the radially aligned nanofibers may have the potential for tissue regeneration in combination with stem cells.

• 한국세라믹학회지
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• 제41권6호
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• pp.425-429
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• 2004

[DEACOOH]-Montmorillonite intercalations complex obtained from Na-Montmorillonite and 10-Carboxy-n-decyldimethylethylammonium bromide (organic cation) was reacted with the monomer ($\varepsilon$-caprolactone) to achieve the [DEACOOH]-$\varepsilon$-caprolactone-Montmorillonite intercalations complex. From this intercalations complex Montmorillonite/Polycaprolactone nanocomposites in which montmorillonite (inorganic polymer) is chemically linked with the polycaprolactone (organic polymer) were formed at 240$^{\circ}C$ by three different methods such as in stoichiometric amounts between monomer and organic cation, in excess of only the monomer and in excess of both organic cation and monomer. The products obtained after polymerization were analyzed with X-ray diffractometer and TEM.

• 한국세라믹학회지
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• 제44권2호
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• pp.71-78
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• 2007

A [TEACOOH]-Montmorillonite intercalations complex obtained from Na-Montmorillonite and 10-Carboxy-n-triethylammonium bromide was used to attempt the polymerization of ${\varepsilon}$-caprolactone between the layer spaces of the intercalations complex to achieve Montmorillonite-Polycaprolactone nanocomposites in which the inorganic material (montmorillonite) is chemically combined with the organic polymer (polycaprolactone). The results of X-ray-, IR-, and TEM-analyses for samples obtained after polymerization showed that a polycondensation reaction was successfully produced. For a more precise investigation of the polymeric reaction products the polymerized products were separated from the silicate layers and analyzed with an IR-spectrometer. A comparison of the results of the IR-analyses of the separated polymer with that of the polymer synthesized by the reaction of ${\varepsilon}$-caprolactone with only the organic cation and without montmorillonite showed that the two obtained polymers are the same compound.