Münir Taşdemir

Properties of Polypropylene Composite Produced with Silk and Cotton Fiber Waste as Reinforcement

The importance of polymer composites among industrial materials is due to their improved mechanical properties. In recent researches, mechanical and physical properties have been improved by way of making composites with fiber reinforcement. Silk and cotton fibers used in the textile industry have good physical and mechanical properties. In this study, composite structures were produced by using recycled Poly Propylene, PP, polymer with silk and cotton waste as fiber reinforcement in different ratios. The fiber dimensions of silk and cotton wastes were between 1 mm, 2.5 mm, and 5 mm. They were mixed in the ratios of PP/silk and cotton waste 97%/3 and 94%/6. The mixture of polymer composite was prepared with double screw extruder. The sample was tested for tensile strength, elongation, yield strength, elasticity modulus, izod impact strength, melt flow index (MFI), heat deflection temperature (HDT), and vicat softening temperature. Thermal transitions of the materials were determined with Differential Scanning Calorimeter (DSC) and micro-structure properties were observed with a Scanning Electron Microscope (SEM).

Characterization of PP/Mg(OH)2 and PP/Nanoclay Composites with Supercritical CO2 (scCO2)

In this article, supercritical carbon dioxide (scCO2) is used to form a high density microcellular foam structure to reduce the polymer use and facilitate dispersion of Mg(OH)2 and Nanoclay fillers. A twin-screw extruder system was used to predistribute the inorganic filler from the PP polymer, resulting composite PP/filler pellets. This followed by the use of a single-screw extruder wherein supercritical carbon dioxide is introduced in the formulation. Finally the resulting foam PP/filler/CO2 pellets are injection molded into test samples. The structure and properties of the composites are characterized using a scanning electron microscopy (SEM), Differential scanning calorimetry (DSC), and density measurements. Furthermore, PP/Clay/Mg(OH)2 polymer composites are subjected to examinations to obtain their yield and tensile strengths, elasticity modulus, % elongation, Izod impact strength, hardness, Heat deflection temperature (HDT), Vicat softening point and Melt flow index (MFI).

Investigation of Sound Absorption and Impedance Ratio of SBR/HIPS Polymer Blends

A sound absorption material composed of styrene butadiene rubber and high impact polystyrene blend has been developed. With the increased amount of HIPS in SBR/HIPS polymer blends, hardness and Izod impact strength values of the resultant material increased. Sound-absorbing characteristics of SBR/HIPS polymer blends were investigated in the impedance tube, according to transfer function method. The sound absorption coefficients are generally above 0.2 with the maximum of 0.5. It reveals that soft blends have good sound absorption ability in 4000 Hz frequency range. For all groups the least sound absorption rate was seen in the area of 315 Hz at the rate of 0.01. With the increase of frequency for all groups impedance ratio decreased. With addition of SBR rubber to the HIPS, the adhesion and distribution of the present phases were considerably enhanced as well.

Mechanical, Morphological and Thermal Properties of SEBS, SIS and SBR-type Thermoplastic Elastomers Toughened High Impact Polystyrene

In this article the effect of PS on the mechanical, thermal and morphological properties of SEBS, SIS and SBR type elastomers –based material was investigated in flow direction 0o and flow direction 90o. The structure and properties of the composites are characterized using a scanning electron microscopy (SEM), Differential scanning calorimeter (DSC) and Energy dispersive X-ray spectroscopy (EDS). Furthermore, SEBS/PS, SIS/PS and SBR/PS polymer blends were subjected to examinations to obtain their elasticity modulus, yield strengths, strength at break, elongation at break, hardness, Izod impact strength, wear rate, melt flow index (MFI), vicat softening point and heat deflection temperature (HDT). In two directions, with the increased amount of HIPS in SEBS/HIPS/CaCO3, SIS/HIPS/CaCO3 and SBR/HIPS polymer blends, the elasticity modulus, yield strengths, strength at break, hardness, Izod impact strength, MFI, HDT, vicat value and wear rate of the resultant material increased, whereas the elongation at break decreased.

Effects of HIPS on the Sound Absorption and Impedance Ratio of SEBS/HIPS/CaCO3 Polymer Composites

A sound absorption material composed of styrene ethylene butadiene styrene, high impact polystyrene and CaCO3 has been developed. Its sound absorbing characteristic was investigated in the impedance tube, according to transfer function method. Measurements show that HIPS ratios have effect on the absorption performance of the blend because of their microstructures and features. The structure and properties of the blend is characterized using a scanning electron microscopy (SEM). Furthermore, styrene ethylene butadiene styrene and high impact polystyrene polymer blend was subjected to examinations to obtain their hardness and Izod impact strength. When the sound absorption characteristics of the materials are examined, a unsteady behaviour is observed up to the level of 1600 Hz. It is determined that sound absorption characteristics of all materials increase after this point. A high and steady behaviour is observed, particularly after 4800 Hz.

Physical and Mechanical Properties of Iron Powder Filled Polystyrene Composites

This article reports on an experimental study of the physical and mechanical properties of Polystyrene (PS) and Fe-PS polymer composites containing 5, 10, and 15 vol.% of Fe powder. After mixing Fe powder and PS in a twin-screw extruder, an injection-molding machine was used to prepare unfilled PS and Fe-PS polymer composite samples. After that, the material properties were experimentally determined for each sample. The investigated material properties included the modulus of elasticity, yield and tensile strength, % elongation, Izod impact strength (notched), hardness (Shore D), melt flow index (MFI), heat deflection temperature (HDT), Vicat softening point, and glass transition temperature (T g ). The results indicated that, compared to the unfilled PS, an addition of Fe into PS decreases the yield and tensile strength, % elongation, and Izod impact strength. Furthermore, it was determined that the Fe particles increase the modulus of elasticity, hardness, MFI, Vicat softening point, and HDT values.

Dynamically vulcanized EPDM/PP (40/60) blends

Dynamically vulcanized thermoplastic elastomer (TPE) blends were first described by Fisher. In the 1960s, the usage of TPE was low. However, the consumption of TPE is increasing today. Due to hard and soft polymer phases in its structure, TPE replaced a lot of materials. TPE materials are preferred today due to their good thermal properties, oxidation resistance, transparency, adhesion, compatibility with other polymers etc. As a result of the studies that were done in 1975, TPV—vulcanized thermoplastic elastomers were developed. In this study, TPV elastomers were produced by forming crosslinks with peroxide from different ratios, of EPDM and PP. Mixing was done with twin screw extruder. After that yield and tensile strength, the modulus of elasticity, % elongation, Izod impact strength, hardness, Melt Flow Index (MFI), Vicat Softening Point, Heat Deflection Temperature (HDT), and density of crosslinks were determined. Thermal transition temperatures and microstructure were determined with DSC and SEM, respectively.

Extrusion with Carbon Dioxide (CO2) and Characterization of ABS/Mg (OH)2/Nanoclay Composites

In this paper, carbon dioxide (CO2) is used to form a high-density microcellular thermoplastic foam structure in order to reduce polymer consumption and facilitate dispersion of Mg (OH)2 and nanoclay fillers. A twin-screw extruder system was used to predistribute inorganic fillers into the ABS polymer, resulting in composite ABS/filler pellets. This is followed by the use of a single-screw extruder wherein supercritical carbon dioxide is introduced into the formulation. Finally, the resulting foam ABS/filler/CO2 pellets are injection- molded into test samples. The structure and properties of the composites are characterized using scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). Furthermore, ABS/Mg(OH)2/nanoclay polymer composite samples are tested to obtain their yield and tensile strengths, elastic moduli, yield and tensile elongations, izod impact strengths, hardness values, heat deflection temperatures (HDT), Vicat softening points, and melt flow indices (MFI). These tests reveal that for the overall reduction in the amount of polymer in the samples, material properties did not generally deteriorate and even showed improvements in some areas. Moreover, resulting injection-molded samples have been shown to possess dimensional integrity due to the continued expansion of CO2 during the molding operation.

Mechanical Properties of Polymers Filled with Iron Powder

Mechanical properties of metal-polymer matrix composites were investigated experimentally. High density polyethylene (HDPE), polypropylene (PP), and polystyrene (PS) were used as the polymer matrix and Fe powder in 5, 10, and 15 vol% was used as the metal. The modulus of elasticity, yield and tensile strength, % elongation, Izod notched impact strength, Shore D hardness, and fracture surfaces of the composites were determined. It was found that vol% Fe reduced the Izod impact strength of HDPE much more than that of PP and PS, while Fe powder increased the hardness of HDPE more than that of PP and PS. Among the composites, PS-Fe composites had higher yield, tensile strength and modulus of elasticity than HDPE-Fe and PP-Fe composites. However, % elongation of PS-Fe composites was lower than that of the other composites. In addition, HDPE- and PP-based composites exhibited ductile type fracture, while PS-Fe composites exhibited brittle type fracture.

Effects of Olive Pit and Almond Shell Powder on Polypropylene

The outgrowing ecological and socio-economic awareness, high consumption of petroleum resources and new environmentally strong regulations especially in European countries have prompted researchers to investigate on green materials compatible with the environment. As replacements for conventional synthetic fibers like aramid and glass fibers, natural fibers are increasingly used for reinforcement in thermoplastics due to their low density, good thermal insulation and mechanical properties, reduced tool wear, unlimited availability, low price, and problem-free disposal. The purpose for the addition of cellulose-based fillers to thermoplastics is to reduce the cost per unit volume and to improve stiffness.In the present work I have prepared a series of filled Polypropylene (PP) composites with olive pit and almond shell flour loading (between 0–40 wt %), to study the effect of the filler content on the mechanical and morphological properties of polypropylene polymer composites.