• Fibers and Polymers
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• v.1 no.2
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• pp.111-115
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• 2000

The effects of nitrile group substitution onto aromatic polyamide backbone on the gas permeability and permselectivity of the polymers are examined. The gas permeability of aromatic polyamides increase with increasing the content of nitrile group substitution, whereas the permselectivity decreases with increasing the nitrile group contents. The effects of chain linrearity on the permeability and permselectivity are also examined. The non-linearity of the polymers increases the permeability. These behaviors are interpreted in terms of chain packing and crystallinity of the aromatic polyamides.

• Journal of Biomedical Engineering Research
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• v.8 no.2
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• pp.135-144
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• 1987

Polyamide microcapsules were designed for a sustained drug release. As a model, riboflavin was e no apsulated in polyamide microcapsules. Polyamide microcapsules were prepared from thiamines and acid bichlorides by the interfacial polycondensation reaction. The diamines used in ttlis works were ethylenediamine and 1, 6-hexamethylenediamine. Sebacoylchloride and teruphthaloylchloride were employed as acid bichlorides. The following parameters were studied; the release of several kinds of polyamide microcapsules , the various concentrations of diamines and acid dichlorides ; the various concentrations of surfactants : the various pH range of sink solution during the dissolution test. The release amount of riboflavin from aromatic polyamide micrcapsule was higher than that of aliphatic polyamide microcapsule The release rate of riboflavin from the polyamide microcapsule was decreased with increase of concentration of thiamines, arid dichlorides and surfactants which is used for preparing polyamide microcapsule. Release riboflavin from polyamide microcapsule was lower at pH 7 than pH 2 in sink-solution for dissolution test.

• Polymer(Korea)
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• v.29 no.6
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• pp.571-574
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• 2005

The aromatic hyperbranched polyamide was synthesized from 5-aminoisophthalic acid by direct polycondensation with triphenylphosphite (TPP) catalyst as a condensing agent. The modification of end-groups in the resulting hyperbranched polymer (HBP) with various alkyl alcohols were conducted. The modification of end-groups of HBP by alkyl groups resulted in an improved solubility in the THF comparing to that of the carboxylic acid-terminated aromatic HBP, Also, 10 wt$\%$ weight loss temperature decreased by increasing the length of alkyl group.

• Journal of the Korean Applied Science and Technology
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• v.25 no.2
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• pp.144-150
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• 2008

The polyamide-amide-imide (PAAI) was synthesized by reacting 4,4'-diaminobenzanilide (DBA) with trimellitic anhydride chloride using a two-stage heating. The precursor of polyamide-acids was formed at first stage and followed by the formation of imide of PAAI. Two polyamide-imides (PAIs) were prepared from benzidine (BZ) or 4,4'-diaminodiphenylether (DPE) with trimellitic anhydride chloride. These three polymers had glass transition temperature in the temperature range of $240-250^{\circ}C$. X-ray data were obtained on thin film specimens cured at $250^{\circ}C$. There was a minimal kind of short-range order consisting of the most probable distances between neighboring chains. The average segmental spacing of short-range order decreased in the order of polymers obtained from 4,4'-diaminobenzanilide (DBA), polyamide-imide, and 4,4'-diaminodiphenylether (DPE). The imidization of three polyamide-imides was confirmed by $^{15}N$ MAS NMR and FT-IR spectroscopy. $^{15}N$ NMR spectrum of cured polyamide-imide showed imide $^{15}N$ peak, thereby providing an evidence for the imidization of three polyamide-imides.

• Applied Chemistry for Engineering
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• v.3 no.4
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• pp.694-700
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• 1992

Aromatic polyamides and polyesters with fexible spacers are prepared by Heck reaction with palladium catalysts In presence of carbon monoxide gas. Dichlorobis(triphenyl phosphine) plladium(II) ($PdCl_2(PPh_3)_2$) and palladium chloride ($PbCl_2$) are used as catalysts. Polyamides and polyesters prepared by his polymerization system have similar transition temperatures. Flexible spacer substituted on phenylene units are varied from hexyl to hexadecyl, the length of spacers effected on transition temperatures of substituted polymers.

• Proceedings of the Korean Fiber Society Conference
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• 1987.06a
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• pp.21-21
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• 1987

• Proceedings of the Korean Fiber Society Conference
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• 1993.06a
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• pp.69-69
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• 1993

• Proceedings of the Korean Fiber Society Conference
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• 1995.10a
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• pp.107-107
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• 1995

• Journal of Adhesion and Interface
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• v.17 no.4
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• pp.136-140
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• 2016

In this study, a series of dimer acid-based polyamides with different diamines were synthesized by condensation polymerization and the polyamides were characterized by Fourier transform infrared spectroscopy (FT-IR). Effects of diamine structures on mechanical and thermal properties of polyamides were investigated. The tensile strength and lap shear adhesion strength of aromatic-based polyamide (DAP) were higher than those of aliphatic-based polyamide (DAH). In DSC thermogram, DAP has a high $T_g$ and $T_m$ compared with DAH. DAP's and DAH's softening point were $112-115^{\circ}C$ and $98-121^{\circ}C$, respectively.

• Proceedings of the Korean Fiber Society Conference
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• 1991.06b
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• pp.83-84
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• 1991