The wet-laid forming system is one of nonwoven manufacturing techniques to produce ideally isotropic webs from the specialty fibers having brittle and high strength properties such as glass, carbon and oxidized carbon fibers. To make the high performance wet-laid nonwovens, the fibers have to be easily dispersed in water with no defects (i. e., log, rope, dumbbell). In this study, we have theoretically suggested the mechanism of fiber dispersion behavior in water under the assumption of dispersion kinetics theory. And then we have experimentally evaluated the effects of processing factors, such as aspect ratio, fiber consistency, dispersing agent and mixing time, on the visibly perceived dispersion of the carbon and oxidized carbon fibers in water. As the results, the water dispersion of carbon fibers is poor with increasing aspect ratio and fiber content, while it does not show any difference when mixing time is increased. The nonionic surfactants on the dispersion of fibers in water are remarkably effective, however the anionic surfactants are not as evident as the nonionic ones. The oxidized carbon fibers are more uniformly dispersed than the carbon fibers in all processing conditions.

Cotton fabric was treated with chitosan-silane mixed solution by pad-dry-cure process to improve the performance properties as well as antimicrobial activity and its washing durability. 98% deacethylated chitosan of 38$\times$10$^4$ molecular weight was selected as antimicrobial agent and methyltrimethoxysilane and gamma-glycidoxypropyltrimethoxysilane were used as flexible binder. Cotton fabric was impregnated with 0.5% chitosan and silane of various concentration. Percent add-on of chitosan and silane increased as the concentration of silane increased resulting in improved antimicrobial activity and washing durability. An application of silane into chitosan finishing bath improved the performance properties of cotton fabric. Tear strength and crease resistance, softness, and whiteness of cotton fabric treated with chitosan-silane composite solution were efficiently improved without significant loss of tensile strength as compared with those treated with chitosan alone. In addition, further improvement of thermal stability of cotton was achieved with silane application.

This paper discussed the assessment of hand of polyester fabrics changed by alkaline hydrolysis. The subjective hand and preference of alkaline hydrolized polyester fabrics were evaluated using the scale developed. The factors affecting consumer's taste for polyester fabrics were analyzed by the statistical technique. The effects of alkaline hydrolysis on the properties of polyester fabrics were evaluated by subjective and objective hand measurements. The results are as follows; As the weight loss increased, evaluators thought that fabrics become lighter, more flexible, more refined, thinner, flossier, and surface property is smoother, finer, softer, and sleeker. They didn't catch the change of moisture related properties. They also thought fabrics became warmer, more flexible, and more spongy as the weight loss increased. As the weight loss increased, the fabric was more preferred. The limited weight loss which changes the preference from 'dislike' to 'like' was 18.6%. The most preferred fabric was that with 58.Seyc of weight loss. The least preferred fabric was the untreated fabric. It is supposed that the preference of fabric was related to the terms such as 'ka-byup-da'(가볍다), 'food-rup-da'(부드럽다), 'pooh-shin-ha-da'(푹신하다), 'moi-ku-rup-da'(매끄럽다), 'hu-mul-geo-ri-da'(흐물거리다), 'chem-chom-ha-da' (촘촘하다), 'ha-nul-ha-nul-ha-da'(하늘하늘하다), 'mi-ku-rup-da'(미끄럽다), 'sum-se-ha-da'(섬세하다), 'tun-ri-goe-ri-ji-an-da'(끈적거리지 않다), 'yon-yon-ha-da'(유연하다), 'ta-tut-ha-da'(따뜻하다), 'too-bak-ha-ji-an-da'(투박하지 않다), 'ya-dul-ya-dul-ha-da'(야들야들하다), 'bo-song- bo-song-ha-da' (보송보송하다), 'yap-da'(얇다).

Polyester filament sewing thread was treated with wax. The sewability was evaluated from the maximum speed of the sewing machine, with which the T/C woven fabric could be sewn over four meters long without thread breakage. The frictional coefficient measured by Capstan method. The frictional coefficient depended on the wax content, the frictional speed, and the temperature of frictional body. It decreased abruptly in the 0~0.3% range of the wax content, and kept the increasing according to the wax content increment. The sewability was improved very much in the 0~0.3% range, and kept the highest level at 1.3% of the wax content. It was suppressed with the excessive wax content.

To evaluate comfort factors of the fabrics, yarn contact angles have been measured. The measurement was made by using a microscope attached with a newly developed specimen mounting device. Variables examined in the experiment were fiber type, yarn twist level, and fluid type. All produced a significant effect on the contact angle of twisted yarn, and the results could be rationalized on the basis of the known concepts related to the contact angle with fibrous materials. The methodology used and the results obtained were discussed in detail.

It was confirmed that the concentration of potassium carbonate in discharging agents with benzaldehyde sodium bisulfite (BASB) was a very important factor affecting the dischargeabilities of vinylsulfonyl reactive dyes such as C.I. Reactive Orange 16 (0-16), C.I. Reactive Blue 19 (B-19) and C.I. Reactive Black 5(Bl-5). Putting colors, C. 1. Reactive Orange 13 (0-13) and C.I. Reactive Blue 15 (B-15), in discharging pastes with potassium carbonate were generally stable but showed a little decrease of color strength of 0-13 resulting from alkaline hydrolysis. When putting color and ground color were in the relationship of complementary color, lightness and saturation of putting color were decreased because of slight residue of ground color in spite of high whiteness. The putting color differences between discharge printing and direct printing decreased with increasing the concentration of potassium carbonate, and it was expected that the dyes of putting colors could contribute to the dischargeability. On the other hand, colored discharge printing of Bl-5 showed large color differences of putting colors due to its poor dischargeability. It was also found that steaming conditions greatly affected the dischargeability of Bl-5.

Poly(trimethylene terephthalate)(PTMT), which is expected to be used as a new polyester fiber, was polymerized from terephthalic acid and 1,3-propanediol and its basic thermal roperties such as glass transition temperature(Tg), melting temperature(Tm) and non-isothermal crystallization behaviors were investigated by differential scanning calorimetry(DSC). Tg of PTMT was 39.5 ℃, which is much lower than that of PET. The equilibrium melting temperature of 244.1 ℃ was obtained from Hoffman-Weeks plots. Multiple melting curves were observed both in isothermally and non-isothermally crystallized samples. In non-isothermal crystallization, the Aramid exponent of about 2.7 and the activation energy of 165 kl/mol were obtained by using 03awa's modified Aramid equation.

In order to manufacture high modulus PPTA fiber, dry-jet wet spinning was carried out at various spinning-speeds, and the fibers obtained were heat-treated at various temperatures and tensions. Morphological properties obtained were investigated corelated with the tensile loads, spinning-speeds and heat-treatment conditions. Initial modulus of PPTA fiber was efficiently increased with right combinanations of spinning-speed and heat-treatment conditions. The initial modulus was more predominately dependent upon the crystallinity than upon the orientation. In addition, the increase of initial modulus was found to be reached to practical maximum in the range of 80~88% of crystallinity, determined by W. Ruland method with WAXD. Consequently, it was investigated experimentally that the process condition could be recommended to be higher than 3.5 of spinning stretch ratio (S.S.R), 3.5 g/d of heat treatment tension, and 470 $^{\circ}C$ of heat-treatment temperature, for the sake of obtaining 80~88% of crystallinity in the spinning and heat-treatment process.

Blends of poly(butylene terephthalate) (PBT) and thermotropic liquid crystalline polymer (LCP) containing 60 mol% p-hydroxybenzoic acid and 40 mol% poly(ethylene terephthalate) were investigated in terms of mechanical, morphological and rheological properties. Mechanical property of PBT/LCP blends was affected by their compositions and fibril formations. Tensile and impact strengths of the PBT/LCP (95/5) blend were one and half times higher than those of PBT itself. Improvement of mechanical properties was obtained by LCP reinforcing effect in the PBT matrix with excellent dispersity and with partial miscibility between PBT/LCP as observed by Scanning Electron Microscope (SEM). Fracture surface of the injection molded samples showed that the LCP formed finely dispersed spherical domains in the PBT matrix, and the LCP domains were the larger spherical droplet with increasing LCP content. However, PBT/LCP (95/5) blend showed tHe smallest LCP droplets in the whole compositions. Addition of 5~10 wt% of LCP slightly increased the melt viscosity of PBT/LCP blends. However, above 10 wt% of LCP content effectively affected a reducing melt viscosity of the PBT/LCP blends, and sharp shear thinning was shown at high shear rate.

The effects of surface treatment of high strength carbon fibers on the impact properties of 2D and 3D carbon fiber reinforced composites and carbon/carbon composites are studied. It is found that air oxidation of carbon fibers deteriorates the impact property of the composites because of declined fiber/matrix interfacial strength due to creation of micro-pore on the carbon fiber surface. The impact property of heat treated (HT700 and HT950) carbon composites is superior to that of any other treated composites because of increased effective surface area of carbon fibers. The 3D structure is suitable for carbon/carbon composite in toughening aspect.