الفهرس 
Chapter 1 General Introduction, Experimental Techniques and Theoretical Consideration for Polymer Fibres InvestigationOnly 14 pages are availabe for public view
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Abstract
This thesis represents a study on the influence of grafting nylon-6 with Poly(methyl methacrylate) PMMA on the optical, structural, mechanical and morphological properties of nylon-6 fibres. The acquired results can lead to new applications and enhance the properties of the blank fibre. Two- and multiple- beam interferometric techniques were used to determine the intrinsic optical, structural, dispersion and optomechanical properties of the two samples. Laser diffraction and computed tomography techniques were used to investigate the geometrical and morphological properties of the two fibres. These studies are presented in details in five chapters throughout the thesis. A general introduction is given in chapter (1) with a review of the previous work devoted to the investigation of nylon-6 polymeric fibre. Moreover, this chapter also introduces a description of the experimental set-up and theoretical considerations of the interferometric techniques used in this work. Grafting is an effective method to enhance the polymers by adding new properties to polymers and overcoming its drawbacks. In the second chapter, Mach-Zehnder interferometer is used to evaluate the grafting effect on the refractive indices and birefringence along the fibre axis of the two fibres. These parameters are keys for other structure-dependent parameters such as polarizability per unit volume, dielectric constant and the surface reflectivity. The results are used to estimate the influence of the grafting process on the blank fibre. Moreover, the laser diffraction technique is utilized to evaluate the geometrical properties of the two fibres. The intrinsic refractive index and birefringence are fundamental optical properties of polymers. They can be used to provide more information about the structural properties. Mechanical drawing is highly related to the molecular chains arrangement and the variation of the drawing can rearrange these chains. In the third chapter, a method was given to determine the intrinsic optical properties, such as the maximum birefringence and maximum refractive indices, depending on measuring the maximum draw ratio of the blank and the grafted fibres. These intrinsic properties allow determining the optical orientation function, orientation angle and the structural constant of the grafted sample. The results reflect the grafting influence on the molecular arrangement of the blank fibre. Dispersion behaviour is a fundamental property in describing the behaviour of the polymeric fibres toward the visible light spectrum. The relation between the incident light wavelength and the refractive index gives the dispersion behaviour. In the fourth chapter, the dispersion properties of nylon-6 blank and nylon-6 grafted with PMMA fibres were investigated using multiple-beam Fizeau fringes and fringes of equal chromatic order (FECO) techniques both in transmission. The Cauchy’s dispersion relation was verified and their constants with the natural wavelength of the samples were calculated. The dispersion and oscillation energies were determined using Sellmeier’s equation. The results showed that the grafting process has changed the dispersion properties of nylon-6 blank fibre. Computed tomography is a non-destructive technique to evaluate the sample internal features. Thus, it is used to characterise the morphology and the influence of grafting on nylon-6 fibres. Pluta polarising interference microscope is a direct tool for rapid determination of the birefringence for polymer fibres. Birefringence distribution investigation can provide valuable information about the structure of the polymer chains. In the fifth chapter, a hybrid technique using Pluta polarising interference microscope and optical computed tomography is suggested to estimate the influence of grafting process of nylon-6 with poly (methyl methacrylate) polymer by determining simultaneously the variations of birefringence values with its morphology at each point across the samples.