Omer Berk Berkalp

Effects of Different Structural Parameters on Carpet Physical Properties

This paper deals with some of the physical properties of face-to-face woven carpets with different structural parameters. Based on appearance retention, abrasion resistance, and tuft withdrawal tests, effective parameters of carpet quality are determined by variance and regression analyses, and the changing characteristics are emphasized in order to direct attention to weaknesses, which are important for total carpet performance.

The effect of hybridization on significant characteristics of jute/glass and jute/carbon-reinforced composites

In this study, four plied jute, carbon, E-glass fabric-reinforced and their hybridized composites are manufactured. Nine composite laminates with different stacking sequences are manufactured by vacuum infusion technique. In order to understand the structure of the composites, fiber weight and fiber volume ratios in the laminate system are initially figured out. Furthermore, void fractions of samples are calculated by using theoretical and experimental densities of the composite samples to examine the impact of amount of fiber content on the void fraction. The effect of hybridizing jute fabric-reinforced polyester composite with E-glass fabric and carbon fabric and also the effect of stacking sequence of fabric layers on the mechanical properties (tensile strength, impact strength) of composite laminates are investigated. According to the outcomes of this investigation, it is realized that incorporating high impact resistant fibers to the outer layers of the composites leads to higher impact resistance, and placing high tensile strength fibers at the inner layers results in higher tensile strength at the hybrid composite laminates.

Utilization of various non-woven waste forms as reinforcement in polymeric composites

In this study, various forms of non-woven waste were recycled for the manufacture of composites by the extrusion technique. The performance of the composites, as well as the effect of the reprocessing steps, was investigated with regards to the mechanical and thermal properties. A reinforcement material of polyester non-woven waste in differing forms (cut piece, fiber and particle) and a matrix of polypropylene (PP) and low-density polyethylene (LDPE) were used. Performance tests were evaluated based on the type of reinforcement material. Particle form reinforced composites were subjected to reprocessing and tested for their performance. Results indicate that particle type reinforcement maintained better mechanical performance, whereas reinforcements using cut pieces and fibers showed enhanced thermal insulation with lower densities. The effect of the reprocessing of the particle forms has been observed positively on the tensile characteristics, especially up to the second stage.

A new approach for the development of textile waste cotton reinforced composites (T-FRP): laminated hybridization vs. coupling agents

Abstract This paper presents two separate methods to improve the tensile strength (TS) of textile waste cotton reinforced polymer composites (T-FRP) as prospective functional materials with respect to environmental concerns. Two very different methods were designed in order to improve the TS of the composite. In the first method, maleated anhydride polyethylene was added as the coupling agent into the composite composition, whereas in the second method, a totally new glass fiber and glass fabric laminated hybrid composite structure was designed. In this first study, the coupling agent was mixed up to 5 wt% into the composite structure in order to improve the bonding interface between low density polyethylene (LDPE) matrix and cotton waste fibers. The effect of the coupling agent was evaluated and compared with the unmodified one. By contrast, chopped glass (CG) fibers and woven biaxial glass fabrics were introduced into the composite layers with the intention of designing a new hybrid composite structure as a second study. The TS of the materials was evaluated and the fracture surface was assessed with an optical microscope. Consequently, an improvement in TS of 50% and 230% was achieved by the addition of the coupling agent and the creation of a new hybrid composite, respectively.

Analysis of the effects of fabric reinforcement parameters on the mechanical properties of textile-based hybrid composites by full factorial experimental design method:

In this study, the effect of some fabric reinforcement parameters (fabric direction, yarn type and stacking sequence) on the mechanical properties of textile based hybrid composites are analysed by using full factorial experimental design method. The analysis of the results is achieved by using Minitab 17 software program. One factor (fabric reinforcement direction) with two levels (warp direction and weft direction) and two factors (yarn type and stacking sequence) with three levels (jute/glass, jute/carbon, glass/carbon and consecutive, low strength inside, high strength inside) are selected as the reinforcement design. Full factorial experimental design analysis results indicate that, the highest tensile and impact strength values among the experimental design are realised when samples are taken from the warp direction and E-glass/carbon combination is chosen as the yarn (material) type. Moreover, it is verified that while higher tensile strength is achieved by placing higher strength fabrics to the inner layers, higher impact strength is achieved by placing high strength fabrics to the outer layers of hybrid composite structures. Analysis of variance tables also show that at 95% confidence level, the effects of the factors are statistically significant (p < 0.05).

THE EFFECT OF REPROCESSING ON THE TENSILE PROPERTIES OF COMPOSITES

In this study, waste cotton fabric reinforced polymer matrix composite material has been manufactured by a custom made recycling extruder. Composites with different reinforcement ratios as 12,5%wt ( 12,5%wtRPE ) and 25%wt ( 25%wtRPE ) were tested for their mechanical properties such as tensile strength and young’s modulus. The material was then granulated down to the size enough to be used in the extrusion process in order to observe the effects of reprocessing. Reprocessing leads to improve Tensile Strength of composite materials and slows down the reduction of tensile strength of polyethylene. It was observed that composite materials were highly affected by the fiber orientation and acts as anisotropic material under the load.