• Food Science and Biotechnology
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• v.18 no.1
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• pp.157-161
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• 2009

Resveratrol-loaded poly($\varepsilon$-caprolactone) (PCL) nanoparticles were prepared by oil in water (O/W) emulsion solvent evaporation method. The morphology of the nanoparticles was evaluated using atomic force microscope (AFM), in which well-shaped and rigid nanoparticles were prepared. The mean particle size of nanoparticles prepared using only dichloromethane (DCM) ($523.5{\pm}36.7\;nm$) was larger than that prepared with a mixture of DCM and either ethanol (EtOH) ($494.5{\pm}29.2\;nm$) or acetone ($493.5{\pm}6.9\;nm$). The encapsulation efficiency of nanoparticles prepared only with DCM as dispersed phase ($78.3{\pm}7.7%$) was the highest of those prepared with solvent mixtures. An increase in the molecular weight of PCL led to an increase in encapsulation efficiency (from $78.3{\pm}7.7$ to $91.4{\pm}3.2%$). Pluronic F-127 produced the smallest mean size ($523.5{\pm}36.7\;nm$) with the narrowest particle size distribution. These results show that dispersed phase, molecular weight of wall materials, emulsion stabilizer could be important factors to affect the properties of nanoparticles.

• Macromolecular Research
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• v.15 no.1
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• pp.39-43
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• 2007

The amphiphilic block copolymer (PEtOz-PCL) of poly(2-ethyl-2-oxazoline) (PEtOz) and poly(${\varepsilon}$-caprolactone) (PCL) formed spherical micellar structures with an average diameter of 26 nm in aqueous phase. Au and Pd nanoparticles with an average diameter of $2{\sim}3nm$ were prepared by using the PEtOz-PCL micelle consisting of a PEtOz shell and PCL core. The Au nanoparticles of PEtOz-PCL micelles in aqueous phase could be transferred into organic phase by using n-dodecanethiol. The use of the Pd-NP/PEtOz-PCL micelle as a nanoreactor for Suzuki cross-coupling reaction was investigated.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.226-226
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• 2006

Ethylene was polymerized with a catalyst having sterically hindered pentamethylcyclopentadienyl ligand, $Cp^{\ast}_{2}ZrCl_{2}/MAO$, and the polymerization mixture were treated with dry oxygen (oxidative workup) to produce hydroxyl-terminated polyethylenes (PE-OH). Polyethylene-block-Poly (${\Box}-caprolactone$) was synthesized from PE-OH and ${\cdot}\^{A}-caprolactone$A by using stannous octoate as a catalyst for ring opening polymerization of ${\cdot}\^{A}-caprolactone$. Polyethylene-block-Poly(methyl methacrylate) was obtained by transforming the hydroxyl-terminated polyethylenes to macroinitiators for atom transfer radical polymerization (ATRP) and by reacting them with MMA.

• Textile Coloration and Finishing
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• v.22 no.3
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• pp.229-238
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• 2010

Poly($\varepsilon$-caprolactone) nano/microcapsules(nmcPCL) containing phytoncide oil were synthesized by emulsion diffusion method using ethyl acetate and poly(vinyl alcohol) (PVA) as an organic solvent and an emulsion stabilizer respectively. The influence of the degree of saponofication of the PVA and the weight ratio of core to wall materials was investigated to design nanocapsules in terms of particle size, morphology, and emulsion stability. The encapsulated nmcPCL were characterized by FT-IR spectrometry, particle size analyzer and scanning electron microscope. Mean size of nanocapsules prepared with PVA with a degree of saponofication of 87% was smaller than those of PVA with a degree of saponofication of 98.5% and the mean particle size of the capsules decreased with increasing core/shell ratio.

• Proceedings of the Korean Fiber Society Conference
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• 2001.10a
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• pp.341-344
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• 2001

Over the last 20 years, biodegradable materials in medical applications have been studied extensively. Among these materials, poly(ε-caprolactone) and poly(trimethylene carbonate)(PTMC) are attractive biopolymers to be used as biodegradable sutures, artificial skin, drug release system. It was known that PCL is a nontoxic biocompatible semicrystalline polymer with melting point of 63℃, and PTMC is an amorphous or little crystaline polymer. (omitted)

• Polymer(Korea)
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• v.36 no.2
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• pp.202-207
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• 2012

Biodegradable poly(${\varepsilon}$-caprolactone)(PCL) microcapsules containing pseudomonas were prepared by W/O/W emulsion system. The characteristics and release behaviors of the microcapsules were investigated as a function of manufacturing conditions. The morphology and particle distribution of the microcapsules were observed by a scanning electron microscope and a particle size analyzer. The release behaviors of the pseudomonas were determined using a cell culture method. It was found that smooth and spherical microcapsules were formed by W/O/W emulsion system and particle size was in the range of 10 to 60 ${\mu}m$. The release behaviors of the pseudomonas were influenced by the manufacturing conditions. It was indicated that the increase of the surfactant content and stirring rate led to an increased release rate, resulting from the high specific surface area of the smaller particle size, and the increase of the PCL content provided the sustained release behaviors by the delay effect of diffusion in the release medium.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2006.11a
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• pp.50-52
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• 2006

• Macromolecular Research
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• v.8 no.4
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• pp.186-191
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• 2000

Clay-dispersed nanocomposites have been prepared by simple melt-mixing of three components, i.e. poly (styrene co-acrylonitrile) copolymer (SAN), poly ($\xi$-caprolactone ) (PCL), and an organophilic clay(Cloisite(R) 30A). In the present study, poly($\xi$-caprolactone) was added in the mixtures in order to facilitate the intercalation of SAN into the gallery of silicate layers, and the molecular weight effects of PCL on the dispersion of silicate layers were compared by changing the amount of added PCL. The degree of dispersion of 10-$\AA$-thick silicate layers of clay in the nanocomposites was investigated by using an X-ray diffractometer and a transmission electron microscope. It was found that PCL added in the mixture facilitate the intercalation of SAN copolymers into the galleries of silicate layers modified with an organic intercalant, resulting in the better dispersion of clay. It was, also, observed that the processing temperature influences the degree of clay dispersion.

• Polymer(Korea)
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• v.27 no.4
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• pp.285-292
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• 2003

The compatibility of poly(lactic acid)/poly($\varepsilon$-caprolactone) (PLA/PCL) blends as a function of blend composition was studied and triphenyl phosphite (TPP) was applied to PLA/PCL blends as a reactive compatibilizer. Especially the effect of compatibility on the crystallization behavior in both PLA/PCL blends and PLA/PCL blends with TPP was considered. PLA/PCL blends were immiscible based on thermal characteristics of PLA/PCL blends and the miscibility was depend upon the blend composition. The enhancement of compatibility was found in PLA/PCL blends with TPP depend upon its content. The rate of crystallization in PLA/PCL blend varied with blend composition. This was understood as the development of nucleation at the interface of PLA-PCL due to the immiscibility. TPP was acting as a compatibilizer as well as an agent for the acceleration of spherulite growth In PLA. As a result, the crystallization rate increased and the size of spherulite became larger than that of PLA/PCL blend without TPP.

• Polymer(Korea)
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• v.27 no.5
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• pp.449-457
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• 2003

The purposes of this work were the producing of a biodegradable poly($\varepsilon$-caprolactone) (PCL) / poly(ethylene oxide) (PEO) microcapsule and the analyzing of form and features for the manufacturing conditions which could be observed in a prospective drug delivery systems through drug release. The effects of emulsifier, emulsifier concentration, and stirring rate for the diameter and form of the microcapsules were observed using image analyzer and scanning electron microscope. The role of interfacial adhesion between PCL/PEO and drug was determined by contact angle measurements, and the drug release test of the microcapsules was characterized by UV/vis. spectra. As a result, the microcapsules were made in spherical fonns with a mean particle size of 170 nm∼68 $\mu$m. And the work of adhesion between water and PCL/PEO increased with increasing the content of PEO, probably due to the increased the hydrophilicity. It was also found that the drug release rate from the microcapsules significantly increased with increasing the content of PEO, which could be also attributed to the increasing of the hydrophilic groups or the degree of adhesion force at interfaces.