Effect of rigid rod molecular structures on the properties of regenerated and virgin poly(ethylene terephtalate)

Duru, C. Zeynep
In recent years,the recycling of plastic waste incerased worldwide.The basic impetus for this increase is the public awereness regarding polltuion of the environment.Many different types of recycling processes are being used to reduce the use of raw materials and to reduce energy consumption.PET recycling is one of the most important recycling processes.addition of thermotropic liquid crystalline polymers has also become wide-spread in recent years to increase their mechanical properties and other selected properties.In this study,it is aimed to obtai a continous or discontinous fiber from the termotropic liquid crystalline copolyester and recycled PET blend.In this study X7G was used as a copolyester.In the polymer mixtures small amounts of liquid crystalline plymer phase resulted in significantr improvements in the mechanical properties of the fibers produced in the study.The blending method used gave an alost homogeneous poymer mixture which was unexpected tat needs further study to elaborate.The preliminary DSC,SEM, tensile testing and intrinsic viscosity measurements support this conclusion.The material obtained approached to fiber grade PET in terms of fiber forming properties which therefore can be used as a second grade fiber material.


Effects of chain extension and branching on the properties of recycled poly(ethylene terephtkalate)-organoclay nanocomposites
Keyfoğlu, Ali Emrah; Yılmazer, Ülkü; Department of Chemical Engineering (2004)
In this study, the effects of chain extension and branching on the properties of nanocomposites produced from recycled poly(ethylene terephthalate) and organically modified clay were investigated. As the chain extension/branching agent, maleic anhydride (MA) and pyromellitic dianhydride (PMDA) were used. The nanocomposites were prepared by twin-screw extrusion, followed by injection molding. Recycled poly(ethylene terephthalate), was mixed with 2, 3 and 4 weight % of organically modified montmorillonite. Du...
Effect of polymer additives on the physical properties of bitumen based composites
Doğan, Mehmet; Bayramlı, Erdal; Department of Polymer Science and Technology (2006)
Polymer modified bitumen is a binder obtained by the incorporation of various types of polymers in bitumen using mechanical mixing or chemical reactions. There are several factors affecting the properties of polymer modified bituminous composites such as; chemical composition of bitumen, kind of polymer and filler, compatibility of bitumen and polymer, amount of bitumen, polymer and filler, particle size of filler and process conditions. The main objective of this study is to determine the effects of polyme...
Synthesis and characterization of polystyrene clay nanocomposites
Özden, Gülsüm; Yılmazer, Ülkü; Department of Chemical Engineering (2004)
This study was undertaken to prepare polystyrene (PS)/montmorillonite (MMT) nanocomposites by different methods, including melt intercalation, in-situ polymerization and masterbatch methods. The in-situ polymerization method consisted of dispersing the styrene monomer into the galleries of MMT followed by subsequent polymerization. The PS/MMT nanocomposites formed by melt intercalation method were prepared on a twin-screw extruder. The masterbatch method was in fact a two-step process. As the first step, a ...
Preparation and characterization of thermally stable organoclays and their use in polymer based nanocomposites
Abdallah, Wissam; Yılmazer, Ülkü; Department of Chemical Engineering (2010)
The present study was aimed at exploring the purification and modification of montmorillonite rich Turkish bentonites by organic salts and their subsequent effects on the morphology (X-diffractometry, transmission electron microscopy, scanning electron microscopy), melt flow index, mechanical (Tensile, Impact) and especially thermal stability (thermal gravimetric analysis, differential scanning calorimetry) properties of polymer/organoclay nanocomposites with and without an elastomeric compatibilizer. The b...
Flame retardancy of polyamide compounds and micro/nano composites
Gündüz, Hüseyin Özgür; Kaynak, Cevdet; Department of Polymer Science and Technology (2009)
In the first part of this dissertation, glass fiber reinforced/unreinforced polyamide 6 (PA6) and polyamide 66 (PA66) were compounded with three different flame retardants, which were melamine cyanurate, red phosphorus and brominated epoxy with antimony trioxide, by using an industrial scale twin screw extruder. Then, to investigate flame retardancy of these specimens, UL-94, Limiting Oxygen Index (LOI) and Mass Loss Cone Calorimeter (MLC) tests were carried out. In addition to flammability tests, thermogra...
Citation Formats
C. Z. Duru, “Effect of rigid rod molecular structures on the properties of regenerated and virgin poly(ethylene terephtalate),” M.S. - Master of Science, Middle East Technical University, 2004.