Difunctional carboxy-terminated poly(2-cyano-1,4-phenylene terephthalamide)(CT-CyPPDT) was prepared by low temperature solution polymerization of 2-cyano-1,4-phenylenediamine(CyPPD) with calcualted excess amounts of terephthaloyl chloride(TPC) in N-methyl-2-pyrrolidone(NMP) and was identified by UV-Vis spectrophotometry. CT-CyPPDT was fractionated by isotropic/anisotropic phase separation using triangular cross-fractionation method ; 10 fractions were obtained. Mark-Houwink relation of unfractionated and fractionated CT-CyPPDT was found to be [η]=2.51${\times}$$10^{-4}M_{n}^{1.02}$ and [η]=1.10${\times}$$10^{-4}M_{n}^{1.05}$ respectively in 97% $H_{2}SO_{4}$ and dimethylacetamide(DMAc) containing 5 wt.% LiCl at 30 $^{\circ}C$. The Mark-Houwink relation for CyPPDT indicates that the conformation is an intermediate worm-like chain between a coil and a rod-like particle. This is confirmed by the formation of anisotropic polymer solution above critical concentrations in 97% $H_{2}SO_{4}$ and DMAc and/or NMP containing inorganic salts such as LiCl.

Difunctional amino-terminated poly(m-phenylene isophthalamide)(AT-PMIA) and poly(2-cyano-1,4-phenylene terephthalamide)(AT-CyPPDT) telechelics were prepared by low temperature solution polymerization of isophthaloyl chloried (IPC) and terephthaloyl chloride(TPC) with calculated excess amounts of m-phenylenediamine(MPD) and 2-cyano-1,4-phenylenediamine(CyPPD) in dimethylacetamide(DMAc) and N-methyl-2-pyrrolidone(NMP), respectively. Purity of amino groups of the telechelics was determined by measuring the molar extinction coefficient(${\varepsilon}_{\lambda}{max}$) of a protonated bis-Schiff base which was formed from the reaction of 4-(dimethylamino) benzaldehyde(DMBA) with diamines in the presence of p-toluenesulfonic acid(TA) in dimethylacetamide(DMAc) containing 2%(wt.) LiCl; the number average moles of amino groups in the telechelics was calculated from their $M_{n}$ using the Mark-Houwink equations for carboxy-terminated PMIA(CT-PMIA) and CyPPDT(CT-CyPPET), i.e., [η]=7.96${\times}$$10^{-4}M_{n}^{0.71}$ and [η]=2.51${\times}$$10^{-4}M_{n}^{1.02}$, respectively. It decreased as reactant mole ratio (${\gamma}$) approached 1.0. It increased, however, as expected on reaction with further excess diamine after the polymerization reaction. Reactivity of amino groups of the telechelics was confirmed by change in intrinsic viscosity([η]) and numberaverage molecular weight($M_{n}$) with the coupling reaction of IPC and TPC.

The crystal structure and isothermal crystallization behavior of random copolyesters based on ethylene terephthalate(ET) and caprolactone(CL) units were investigated by melting point depression, X-ray diffraction and polarizing microscope equipped with a hot stage. The melting point depression begavior of P(ET/CL) random copolyesters with increasing contents of CL units was closest to that predicted by the Baur equation rather than the Flory equation. Therefore P(ET/CL) random copolyesters appear to exhibit pseudoeutectic type crystal structure where the melting point depression depends not only on the composition but also the segment lengths. In the X-ray analysis, the diffraction angle and d-spacing values of P(ET/CL) random copolyesters were changed. It appears that the unit cell structure has been deformed slightly. Thus small amounts of CL unit appear to have been incorporated into the crystal as defects. The crystallization rate of the P(ET/CL) random cololymers depended on the segment length and composition of ET units, and incorporation of CL units generally decreased the crystallization rate of P(ET/CL) copolymers. However, the copolymer containing 13 mole % CL units exhibited an increase in the crystallization rate. This appears to be due to the enhanced mobility of the copolymer chain and the sufficiently long ET segments which insures anchoring of the segments to the growing crystal.

An attempt was made to synthesize an adsorbent by the photo-induced grafting of acrylic acid(AA) onto polypropylene nonwoven using benzophenone(BP) as a photosensitizer in an $CH_{3}OH-H_{2}O$ medium. As BP concentration was increased, the gragt yield was increased up to a specific value and then decreased, and the effect of AA concentation showed the same tendency. it was also found that the graft yield increased with reaction time and reaction temperature. The amount of ammonia gas absorbed by AA grafted polypropylene(PP-g-AA) nonwoven was dependent on the graft yield, adsorption time and ammonia gas pressure. The adsorption capacity of ammonia gas by the PP-g-AA nonwoven with graft yield of 11.6% was 5.68 mmole/g, which is much higher than that of active carbon or silica gel.

Composite materials reinforced with fabric preforms made by weaving, braiding or knitting yarns are currently being considered as alternatives to tape laminates. Such fabric reinforced "textile" composites have potential for improved impact and delamination resistance. In this study, braid composites of 2${\times}$2 and 2D triaxial fabricated under different braid angle by using parallel yarns. Middle-end yarns were inserted between the braider yarns and axial yarn were inserted in circular braids. The tensile properties decreased with the increase in the braid angle. The tensile strength of inlaid axial yarn composites was higher than that of inlaid middle-end yarn composites. The tensile strength of 2D triaxially braided composites could be calculated by using braid parameters such as braid structure, yarn size, yarn spacing, and crimp.

A new evenness evaluation method was developed in order to analyze short-termirregularity of spun yarns. The diameters of a spun yarn were measured at every 2 mm segments by using the G-580\ulcorner tester produced by Zweigle Ltd. Simultaneously, the analog signals from the instrument were captured and then converted into the digital signals with the digital signal processing system specially developed for this study by using Lab-PC+\ulcorner. In order to analyze the periodicity of the signals, Short-Time Fourier Transform(STFT) and Discrete Fourier Transform(DFT) were applied. The results from STFT were compared with those from DFT. It was found that STFT was more effective in analyzing the short-term irregularity of spun yarns than DFT and in detecting frequency content changes with time.

Using Peirce's model of plain woven fabrics, mathematical equations that can be used to predict the structure and mechanical behaviors were derived and their solutions were obtained. The structure of woven fabrics was defined in terms of the yarn number, fabric density, and yarn crimp, and the effects of these variables on the fabric structure were investigated. The boundary of structure of fabrics where Peirce's geometrical model could still be successfully applied was determined and the Poisson's ratio under uni-axial extension was obtained. The energy method was employed in order to derive mathematical equations for estimating mechanical properties of fabrics from the mechanical properties of yarns and the structural parameters of fabrics. Furthermore, the effects of intial modulus and bending rigidity of yarns on the load-extension relationships of woven fabrics were investigated.

Reaction of 2,3-dichloro-5,6-dicyanopyrazine with various Fisher's base type enamines gave the corresponed 2-chloro-5,6-dicyanopyrazine derivatives. The reactive-disperse dye showed large differences in ${\lambda}_{max}$ from solution to solid state resulting from strong intermolecular π-π interactions. These dyes have rather small molecular size but have a strong intermolecular charge-transfer chromophoric system. The absorption maxima of these compounds were observed at 463∼560 nm. The electronic character of the substituents in dyes strongly after their absorption spectra, producing bathochromic shifts depending on both the basicity of the heterocyclic moiety and the enlargement of the π-conjugated system. The dyeability of the two dyes toward polyester and nylon fiber were generally good. Wash, perpiration and rubbing fastness were excellent, while light fastness was poor probably due to the oxidation of the enamine moity.