Investigation of Mechanical and Microstructural Properties of Polyolefin Rubber and Glass Beads Filled Polypropylene Composites

Abstract

In the automotive industry and many industries, parts are expected to meet certain requirements with regards to their tensile strength, stiffness, and high impact strength. For this reason, polypropylene homopolymer, which is a fragile polymer widely used in the automotive industry, is combined with additives to reduce its fragility. In this study, the mechanical and microstructural properties of polyolefin rubber and glass bead filled polypropylene composites have been investigated. Polypropylene (PP) was combined with polyolefin rubber (POE) and glass beads (GB) at different weight rates to create the composites and pure polypropylene was compared to the three prepared PP composites; 8% polyolefin rubber by weight, 8% glass bead by weight, and 8% polyolefin rubber and 8% glass bead by weight. The fracture surface examinations of the pure polypropylene (PP), and the polyolefin rubber added PP, glass bead added PP, and polyolefin rubber and glass bead added PP composites were carried out using Scanning Electron Microscopy (SEM). In addition, Energy Dispersive Spectroscopy (EDS) analysis was also performed for the characterization. It was observed that the tensile strength values of the PP composites (PP-8%POE, PP-8%GB, and PP-8%POE-8%GB) showed a slight decrease relative to the pure PP. When rigid glass beads were added to the pure PP polymer main matrix (8% by weight), the stiffness of the composite increased and the modulus of elasticity increased by approximately 8% relative to pure PP. In addition, it was observed that the % elongation at break values of the PP composites (PP-8%POE, PP-8%GB, and PP-8%POE-8%GB) increased significantly relative to the values for pure PP.

Keywords

• Polypropylene
• Polyolefin rubber
• Glass beads
• Mechanical properties

Cam Bilya ve Termoplastik Poliolefin Elastomer Katkılı Polipropilen Kompozitlerin Mekanik ve Mikroyapı Özelliklerinin İncelenmesi

Öz

Otomotiv endüstrisinde ve birçok uygulama endüstrisinde, parçaların çekme mukavemeti, rijitliği ve yüksek darbe mukavemeti ile ilgili belirli gereksinimleri karşılaması beklenir. Bu nedenle otomotiv endüstrisinde yaygın olarak kullanılan kırılgan bir polimer olan polipropilen homopolimer, kırılganlığını azaltmak için katkı maddeleri ile birleştirilir. Bu çalışmada, poliolefin kauçuk ve cam bilya dolgulu polipropilen kompozitlerin mekanik ve mikroyapısal özellikleri araştırılmıştır. Polipropilen (PP), kompozitleri oluşturmak için poliolefin kauçuk (POE) ve/veya cam bilyalar (GB) ile farklı ağırlık oranlarında birleştirildi ve saf polipropilen hazırlanan üç PP kompoziti ile karşılaştırıldı; Ağırlıkça %8 poliolefin kauçuk, ağırlıkça %8 cam bilya ve ağırlıkça %8 poliolefin kauçuk ve %8 cam bilya. Saf polipropilen (PP) ve poliolefin kauçuk katkılı PP, cam bilya katkılı PP ve poliolefin kauçuk ve cam bilya katkılı PP kompozitler üzerinde çekme testleri yapılarak elde edilen çatlak kırılma yüzeylerinin görüntüleri Taramalı Elektron Mikroskobu (SEM) ve mikro yapı incelemeleri için Enerji Dağılım Spektroskopisi (EDS) alınmıştır. PP kompozitlerin (PP+%8POE, PP+%8GB ve PP+%8POE+%8GB) çekme mukavemet değerlerinin saf PP'ye göre hafif bir düşüş gösterdiği gözlemlendi. Saf PP polimer ana matrisine (ağırlıkça %8) sert cam bilyalar eklendiğinde, kompozitin sertliği arttı ve elastisite modülü, saf PP'ye göre yaklaşık %8 arttmıştır. Ayrıca PP kompozitlerin (PP+%8POE, PP+%8GB ve PP+%8POE+%8GB) kopma anındaki uzama yüzdesinin saf PP değerlerine göre önemli ölçüde arttığı gözlemlenmiştir.

Anahtar Kelimeler

• Polipropilen
• Poliolefin kauçuk
• Cam bilya
• Mekanik özellikler

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