Crystallization kinetic of blends of thermotropic liquid crystalline polymer p-hydroxybenzoate-ethylene terephthalate copolyester (PHB-80 PET20) with PET or poly(ethylene 2, 6-na-phthalate)(PEN) was investigated to understand crystallization behavior of (PHB80-PET20)/PEN/PET ternary blend. Non-isothermal and isothermal crystallization processes of the blends were investigated on a differentail scanning calorimeter (DSC). The crystallization kinetic was calculated by using Avrami and Ozawa equations as a function of time or temperature. The calculated Avrami exponents revealed three-dimensional growth of crystalline regions for each blend. The rate of crystallization of each blend was increased with the decrease in crystallization temperature, and the rate of crystallization of (PHB80-PET20)/PEN blend was faster than that of (PHB80-PET20)/PET. Spherulitic morphology exhibiting maltese cross was confirmed by the Avrami exponent. Spherulite size of binary blends was smaller than that of pure PET and PEN.

The effect of aqueous ammonia treatment on th physical properties and structure of PET tire cord fiber having different long periods was investigated. It was found that degradation occurred mainly in the amorphous region in the initial stage, and then occurred in the crystalline region. The tenacity decreased with increase in aqueous ammonia treatment time and temperature. Molecular relaxation seems to be a dominant process during the initial stage of aqueous ammonia treatment. As the treatment time increases, chain scission appears to occur remarkably at the later stage. Aqueous ammonia treatment exhibited stronger effects on the change of physical properties and fine structure of a sample having a smaller long period than on samples having larger long periods. From these results, it is found that the chemical treatment of PET tire cord is quite different from the result observed through physical treatment (repeated extensional fatigue) in physical properties and structure.

In order to study the relationship between fiber structure and physical properties during the drawing process, undrawn and drawn polypropylene multifilaments were manufactured on a spin-draw melt spinning machine and tested with a universal tester equipped with a temperature cabinet. The birefringence, density, and crystallinity of undrawn polypropylene multifilaments increased in the lower spinning temperature range with higher take-up velocity. In the case of drawn polypropylene multifilaments, the values of birefringence, density, crystallinity, tenacity, and elongation increased in the range of low take-up velocity until it was drawn to maximum ratio. For example, when drawn at a rate of 200 m/min, the maximum values of tenacity, elongation, and Young's modulus of the multifilaments were 8.5 g/d, 18.4%, and 48.8 g/d, respectively.

The effects of needle design parameters (total number of barbs, barb spacing and kick-up size), needling density and fiber web basis weight on the mechanical properties (breaking energy, tear strength and puncture resistance index) of the needle-punched fabrics were studied. The total number of barbs and the barb spacing showed significant effects on the needle-punched fabric's properties while the kick-up size did not. The breaking energy increased as the needling density was increased up to a certain level of needling density. The tear strength was decreased as the needling density increased. Due to the sizes of the clamp, the probe and the samples, the puncture resistance index did not show significant difference with the needling density. The fiber-web basis weight enhanced the mechanical properties of the fabrics.

Although many papers have been published on the mechanical properties of nonwoven fabrics, there is no report on the relationship between tensile and puncture properties. For the further application of lightweight nonwoven products in uses such as protective materials, the complete understanding of this relationship should be needed when they are subjected to puncture force. The objectives of this research are to assess the tensile properties with different tensile test methods and to compare the theoretical puncture force calculated by tensile property and experimental puncture force. In the our work, two test methods were used for the tensile properties: uniaxial and biaxial tests. The tensile strength of MD and CD direction. If the condition of tensile test was similar to puncture test, the test method would be in good agreement for predicting the puncture forces. A good correlation between calculated and experimental puncture forces was obtained in the order of biaxial, wide width strip, cut strip, and grab methods.

The effects of temperature in fiber drawing process on two different polyesters, undrawn yarn (UDY) and partially oriented yarn (POY), were investigated. Drawing temperature was varied from the glass transition temperature ($T_{g}$) of polyester (7$0^{\circ}C$) by 4$^{\circ}C$ intervals up to 94$^{\circ}C$ to study the relationship with structural variations, such as initial modulus, orientation, crystallization, and fiber evenness. Furthermore, we also tried to delineate the dyeing properties of polyester fibers which had been drawn at different temperature. results indicated that the increase in drawing temperature enhanced fiber evenness in drawing of POY, while the opposite trend was shown in the case of UDY. In both cases, the dye exhaustion was not varied and the dyeing rate was slightly increased with the drawing temperature.

Alkaline hydrolysis was carried out on PTMT fibers and the changes in the properties of the hydrolyzed PTMT fiber were investigated. PTMT fibers were hydrolyzed in LiOH, NaOH, and KOH solutions, and the hydrolysis rates of PTMT fibers were in the order of LiOH, NaOH, and KOH. The weight loss increased proportionally with increase in treatment time. In general, the hydrolysis rate of PTMT fiber was lower than PET under the same treatment conditions. Intrinsic viscosity, melting temperature, and density data of the hydrolyzed PTMT fibers indicated that the hydrolysis occurred mainly at the fiber surface. The hydrolysis rate constants of the PTMT fibers were calculated and the hydrolysis activation energy of PTMT fiber obtained from Arrhenius plot was 24 kcal/mol, which was lower than that of PET, 15~19 kcal/mol. Addition of diols such as ethylene glycol and 1,3-propanediol in NaOH solution had little effect on hydrolysis rate, but the presence of n-alcohol increased the hydrolysis rate. The hydrolysis rate was influenced by varying the n-alcohol and its concentrations At 10% (v/v) concentration, the hydrolysis rate increased in the order of methanol, ethanol, n-propanol, and n-butanol. Further increase in the number of carbon did not increase the rate. Thus, the hydrolysis rates of n-hexanol and n-pentanol were even slower than that of n-butanol.

Liquid ammonia is known to be effective in improving the soft hand of cotton fabrics. In this study, desized and scoured cotton fabric is treated with liquid ammonia ($NH_{3}$) and sodium hydroxide(NaOH)/liquid ammonia ($NH_{3}$) and subsequently hot water and high pressure steam processing. Washing shrinkage, crease resistance, moisture regain, water absorbency, dyeability, and KES mechanical properties and tensile properties are measured. Excellent shrinkage resistance is obtained by hot water processing, but not by high pressure steam processing. Crease resistance and water absorbency shows almost no change with hot water and high pressure processing. Dyeing rate increases a little and equilibrium dye uptake decreases with hot water, while both parameters decrease remarkably with high pressure steam. Shearing modulus G, bending modulus B, and their hysteresis width 2HG, 2HG5, 2HB are calculated on the basis of the curves. B and 2HB decrease with the hot water processing after the treatment with $NH_{3}$ and NaOH/$NH_{3}$. Softness of hand is not improved by high pressure steam processing.