• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.52-55
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• 2003

Poly (ethylene 2, 6-naphthalate) (PEN) has been used for a high performance engineering plastics such as fiber, film, and packaging, because of excellent physical properties and outstanding gas barrier characteristics [1-2]. However, the application of PEN is limited because PEN exhibits a relatively high melt viscosity. Recently, many researches for organic/inorganic composites by applying nano-particles to the polymer matrix have been carried out [3], and the nano-particles exhibited greatly improved mechanical and rheological properties [4]. (omitted)

• Proceedings of the Korean Fiber Society Conference
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• 2003.10a
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• pp.65-66
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• 2003

Ternary blend fibers (TBFs) based on melt blends of PEN, PET, and TLCP were prepared by melt blending and spinning to achieve high performance fibers. The reinforcement effect and the TLCP fibrillar structure resulted in the improvement of mechanical properties for TBFs. Molecular orientation was an important factor in determining the tensile strength and modulus of TBFs. Another part of this research is silica nano-particle filled PEN composites were melt-blended to improve mechanical and physicalproperties, and processability. The tensile modulus and strength were improved adding silica nano-particles to the PEN. The decreased melt viscosity by the fumed silica resulted in the improvement of the processability. The fumed silica may act as a nucleating agent in the PEN matrix.

• Proceedings of the Korean Fiber Society Conference
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• 2003.10a
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• pp.88-89
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• 2003

A series of novel spinning acrylic polymer containing silk protein were synthesized by copolymerization of acrylonitrile (AN) and silk fibroin peptide (SFP) modified by acryloyl chloride (AC) with vinyl groups. The viscosity values of these copolymers showed that the copolymers have good spinnability, which are synthesized under the condition of putting a micro amount of metal ions into synthesizing solvent. The fiber based on the poly (AN-co-SFP) was prepared and characterized by SEM, FTIR measurement of its shell and core flakes, and moisture absorption. The fiber appeared a smooth surface and could be assumed to have excellent adhesive between SFP and PAN. Furthermore, these fibers showed a shell-core structure and excellent moisture absorption.

• Macromolecular Research
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• v.17 no.12
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• pp.995-1002
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• 2009

Luminescent polynorbornene (PNB)/quantum dot (CdSe@ZnS; QD) composite nanorods and nanotubes were successfully prepared using anodic aluminum oxide (AAO) membranes of various pore sizes as templates. To protect QDs with high quantum yield from quenching during the phosphoric acid treatment used to remove the AAO templates, chemically stable and optically clear norbornene-maleic anhydride copolymers (P(NB-r-MA)) were employed as a capping agent for QDs. The amine-terminated QDs reacted with maleic anhydride moieties in P(NB-r-MA) to form PNB-grafted QDs. The chemical- and photo-stability of QDs encapsulated with PNB copolymers were investigated by photoluminescence (PL) spectroscopy. By varying the pore size of the AAO templates from 40 to 380 urn, PNB/QD composite nanorods or nanotubes were obtained with a good dispersion of QDs in the PNB matrix.

• Journal of Sensor Science and Technology
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• v.30 no.3
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• pp.185-189
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• 2021

Herein, we propose a functional polymer cantilever to enhance maturation and contractile force of cardiomyocytes. The proposed cantilever consists of a surface-patterned polymer substrate and silver nanowires (AgNWs). The AgNWs are transferred to the PDMS substrate using conventional molding techniques. This thin metallic surface significantly improves the adhesion of cardiomyocyte on the surface-patterned PDMS with the hydrophobic characteristics. In addition, the use of AgNWs improves the visibility of the conducting PDMS substrate for the observation of cardiomyocyte through an inverted microscope. The AgNWs also assist in synchronizing each cardiomyocyte to maximize its contractile force.

• Polymer(Korea)
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• v.31 no.1
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• pp.25-30
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• 2007

The characteristics of crosslinking and physical properties in partially crosslinked waste high density polyethylene (HDPE) were studied by introducing reactive melt processing with perbutyl peroxide (PBP). It was found that impurities in waste HDPE affected the crosslinking kinetics. Decrease in density and heat of fusion were observed in partially crosslinked HDPE while its melt viscosity increased. It was explained that impurities in waste HDPE enhanced the crosslinking compared to pure HDPE As a result, dramatic mechanical property improvement was achieved in the waste HDPE by crosslinking reaction.

• Elastomers and Composites
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• v.55 no.3
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• pp.167-175
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• 2020

Various studies have been conducted to improve silica dispersion of silica filled tire tread compounds; among them, silica wet masterbatch (WMB) technology is known to be suitable for manufacturing silica filled compounds that have high silica content and high dispersibility. Till now, the WMB study is focused on the natural rubber (NR) or emulsion styrene-butadiene rubber (ESBR) that does not have a silica-affinity functional group, and a study of NR or ESBR having a silica-affinity functional group is still not well known. Unlike the dry masterbatch technology, the WMB technology can solve the problems associated with the high Mooney viscosity when applied to silica-friendly rubber. However, a coagulant suitable for each functional group has not yet been determined. Therefore, in this study, different coagulant applied silica WMB was prepared by applying calcium chloride, sulfuric acid, acetic acid, and propionic acid by using a carboxyl group functionalized reversible addition fragmentation chain transfer ESBR. The evaluation of the WMB compounds revealed that the calcium chloride added WMB compound showed excellent silica dispersion, abrasion resistance, and rolling resistance.

• Macromolecular Research
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• v.11 no.1
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• pp.62-68
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• 2003

Thermotropic liquid crystalline polymer (TLCP)/poly(ethylene 2,6-naphthalate) (PEN)/poly(ethylene terephthalate) (PET) ternary blends were prepared by melt blending, and were melt-spun to fibers at various spinning speeds in an effort to improve fiber performance and processability. Structure and property relationship of TLCP/PEN/PET ternary blend fibers and effects of annealing on those were investigated. The mechanical properties of ternary blend fibers could be significantly improved by annealing, which were attributed to the development of more ordered crystallites and the formation of more perfect crystalline structures. TLCP/PEN/PET ternary blend fibers that annealed at 18$0^{\circ}C$ for 2 h, exhibited the highest values of tensile strength and modulus. The double melting behaviors observed in the annealed ternary blend fibers depended on annealing temperature and time, which might be caused by different lamellae thickness distribution as a result of the melting-reorganization process during the DSC scans.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.214-217
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• 2003

In recent years the focus of research in dye chemistry has largely changed from involvement in the traditional chemistry of dyes and pigments to investigations of functional dyes. With the development of the elcetronics and information industries, the importance of functional dyes has increased. Many research papers have been published concerning new synthetic methods and mechanicsm of functional dyes. Highly functionalized dicyanopyrazine derivatives can be used as fluorescent dyestuffs, emitters for electroluminescent devices tec. (omitted)

• Bulletin of the Korean Chemical Society
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• v.34 no.9
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• pp.2835-2838
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• 2013