• Title/Summary/Keyword: polycaprolactone

Search Result 136, Processing Time 0.031 seconds

Miscibility and Mechanical Properties of Polycaprolactone-polyamide Block Copolymer/Poly(vinyl chloride) Blend (Polycaprolactone-폴리아미드 블록공중합체/Poly(vinyl chloride) 블렌드의 상용성과 기계적 성질)

  • 안소봉;이하용;정한모
    • Polymer(Korea)
    • /
    • v.24 no.1
    • /
    • pp.128-132
    • /
    • 2000
  • The miscibility between poly(vinyl chloride) (PVC) and polycaprolactone (PCL)-polyamide block copolymer whose content of PCL block is 62.7 wt%, was studied by differential scanning calorimetry. The PCL segment in the block copolymer and PVC has the miscibility showing single glass transition temperature (T$_{g}$). The miscible PVC molecule inhibited the crystallization of PCL segment, making an amorphous homogeneous phase of PCL and PVC segments at high PVC content. The blends had rubber elasticity at the temperature range between the T$_{g}$ of amorphous homogeneous phase of PCL and PVC segments and the melting temperature of polyamide segment, when both phases coexist.ist.

  • PDF

Effect of Polycaprolactone on the Mechanical Properties of PEG/HMX Propellant (Polycaprolactone이 PEG/HMX 추진제의 기계적 성질에 미치는 영향)

  • 정병훈;홍명표;임유진
    • Journal of the Korean Society of Propulsion Engineers
    • /
    • v.2 no.3
    • /
    • pp.62-69
    • /
    • 1998
  • Mechanical properties of polyethyleneglycol(PEG)/cyclo-tetramethylene tetranitramine(HMX) propellant were studied by adding polycaprolactone(PCP) and silane derivatives as coupling agent. Mechanical properties of the propellant were enhanced by increasing the content of PCP which was partially replaced with PEG. PCP/HMX propellant showed 17% increase in maximum tensile strength and 59% increase in elongation compared to those of PEG/HMX propellant. However, as the content of PCP was increased, the hydrolytic stability of this propellant was found to be deteriorated due to the ester group of PCP by measuring hardness drop of cured propellant and swell ratio difference of PEG/PCP binder stored at $40^{\cire}C$ and 90% relative humidity. Hardness of the PEG/PCP/HMX propellant was decreased with increasing triethoxysilyl propionitrile(TESPN) and dinitrosalicylic acid (DNSA) content from accelerated aging at $60^{\cire}C$.

  • PDF

Soil Microorganism Degrading Polycaprolactone (Polycaprolactone을 분해하는 토양미생물)

  • Kim Mal-Nam
    • Korean Journal of Environmental Biology
    • /
    • v.22 no.3
    • /
    • pp.400-404
    • /
    • 2004
  • Polycaprolactone (PCL), a synthetic aliphatic polyester, was buried in activated sludge soil for 66 days at $27^\circ{C}$ and $37^\circ{C}$. The morphology of the surface of PCL film degraded by soil microorganisms was observed. Soil microorganisms degrading PCL were isolated and identified. Soil fungi and soil bacteria utilizing PCL as carbon or energy source were identified as Paecilomyces fumosoroseus KH27, Penicillium digitatum KH28, Fusarium solani KH29, Aspergillus sp. KH30 and Ochrobactrum anthropi KH31, respectively. Biodegradation test of PCL by the isolated strains showed that, P. digitatum KH28 exhibited the most PCL degrading activity at $27^\circ{C}$. However, at $37^\circ{C}$ O. anthropi KH31 showed higher degrading activity than the other soil microorganisms tested.

Highly Homogeneous Carbon Nanotube-Polycaprolactone Composites with Various and Controllable Concentrations of Ionically-Modified-MWCNTs

  • Lee, Hae-Hyoung;Shin, Ueon-Sang;Jin, Guang-Zhen;Kim, Hae-Won
    • Bulletin of the Korean Chemical Society
    • /
    • v.32 no.1
    • /
    • pp.157-161
    • /
    • 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.

Cranioplasty Using Three-Dimensional-Printed Polycaprolactone Implant and Free Latissimus Dorsi Musculocutaneous Flap in a Patient with Repeated Wound Problem following Titanium Cranioplasty

  • Hee Tae Koo;Jeongseok Oh;Chan Yeong Heo
    • Archives of Plastic Surgery
    • /
    • v.49 no.6
    • /
    • pp.740-744
    • /
    • 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.

Synthesis and Properties of Polyester System Polyurethane without Solvent (무용제 반응에 의한 폴리에스테르계 폴리우레탄의 합성 및 특성)

  • Kwak Noh-Seok;Yang Yun-Kyu;Jeong Boo-Young;Hwang Taek-Sung
    • Polymer(Korea)
    • /
    • v.29 no.4
    • /
    • pp.344-349
    • /
    • 2005
  • Polyurethanes(PUs) were synthesized by reaction of isophorone diisocyanate, acetylbutyl citrate, and 3 types of polycaprolactone diol. Their structures were confirmed by FT-IR and NMR spectrometer. And, their thermal and mechanical properties were measured by TGA ud UTM. The effective network chain lengths ($\bar{M}_c$), measured by compressive modulus apparatus, were about $8000\~24000$ g/mol. As crosslinking density and amount of hard segment increased, tensile strength increased and elongation decreased. As the crosslinking density of PUs increased, thermal property inproved. When the ratio of NCO/OH is 1.1, maximum crosslinking density was achieved.

High-Pressure Phase Behavior of Polycaprolactone, Carbon Dioxide, and Dichloromethane Ternary Mixture Systems (Polycaprolactone, 디클로로메탄, 이산화탄소로 구성된 3성분계 고압 상거동 측정)

  • Gwon, JungMin;Shin, Hun Yong;Kim, Soo Hyun;Kim, Hwayong
    • Korean Chemical Engineering Research
    • /
    • v.53 no.2
    • /
    • pp.193-198
    • /
    • 2015
  • The high-pressure phase behavior of a polycaprolactone (Mw=56,145 g/mol, polydispersity 1.2), dichloromethane, and carbon dioxide ternary system was measured using a variable-volume view cell. The experimental temperatures and pressures ranged from 313.15 K to 353.15 K and up to 300 bar as functions of the $CO_2$/dichloromethane mass ratio and temperature, at poly(D-lactic acid) weight fractions of 1.0, 2.0, and 3.0%. The correlation results were obtained from the hybrid equation of state (Peng-Robinson equation of state + SAFT equation of state) for the $CO_2$-polymer system using the van der Waals one-fluid mixing rule. The three binary interaction parameters were optimized by the simplex method algorithm.

Radially patterned polycaprolactone nanofibers as an active wound dressing agent

  • Shin, Dongwoo;Kim, Min Sup;Yang, Chae Eun;Lee, Won Jai;Roh, Tai Suk;Baek, Wooyeol
    • Archives of Plastic Surgery
    • /
    • v.46 no.5
    • /
    • pp.399-404
    • /
    • 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.

Synthesis and Charactrization of Polycaprolactone Nanocomposites Reinforced with Montmorillonite

  • Cho, Sung-Jun
    • Journal of the Korean Ceramic Society
    • /
    • v.41 no.6
    • /
    • pp.425-429
    • /
    • 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.

Formation and Characterization of Chemically Combined [TEACOOH]-Montmorillonite/Polycaprolactone Nanocomposites

  • Cho, Sung-Jun
    • Journal of the Korean Ceramic Society
    • /
    • v.44 no.2 s.297
    • /
    • pp.71-78
    • /
    • 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.