MWCNT Takviyeli Poliüretan Nanokompozitlerin Mekanik Özellikleri ve Hasar Davranışları

Öz

Nanomalzemeler sahip oldukları üstün mekanik özellikler, ısıl kararlılık ve hafiflik gibi özelliklerinden dolayı kompozit malzemelere alternatif olarak geliştirilmiştir. Bu çalışmamızda, ağırlıkça farklı oranlarda çok cidarlı karbon nanotüp (MWCNT) takviyeli/takviyesiz poliüretan nanokompozit malzemelerin statik yük altında çekme ve sertlik testleri yapılarak sonuçları incelendi. Ağırlıkça % 0.25 ,% 0.35 ve % 0.45 oranlarında MWCNT takviyeli poliüretan nanokompozit malzemeler ASTM D638 standardına göre hazırlanarak, elastiklik modülü, çekme dayanımı, tokluk, birim şekil değişimi ve sertlik değerleri saf poliüretan ile karşılaştırılmıştır. Sertlik ölçüm testleri Shore D skalasına göre yapılmıştır. Saf poliüretan malzemenin çekme dayanımı ve elastiklik modülü sırasıyla 20.94 MPa ve 0.601 GPa iken ağırlıkça % 0.45 oranında MWCNT ilave edilmiş poliüretan nanokompozit malzemelerde % 11.0 ve % 79.0 artış oranıyla çekme dayanımı 26.80 MPA ve elastiklik modülü 1.077 GPa elde edilmiştir. Ayrıca hasar mekanizmalarını belirlemek için kırık yüzeyler Taramalı Elektron Mikroskobu (SEM) ile incelenmiştir.

Anahtar Kelimeler

• MWCNT
• Poliüretan
• Nanokompozit
• Mekanik özellikler
• Hasar mekanizmaları

Mechanical Properties and Damage Behavior of MWCNT Reinforced Polyurethane Nanocomposites

Öz

Nanomaterials have been developed as an alternative to composites due to their superior mechanical properties, thermal stability and lightweight. In this study, tensile and hardness tests on different proportions of multi-walled carbon nanotube (MWCNT) reinforced/unreinforced polyurethane nanocomposite materials under static loading were investigated. They were prepared according to ASTM D638 standard and reinforced with MWCNT with the mass ratio of 0.25%, 0.35% and 0.45%. Their modulus of elasticity, tensile strength, toughness, elongation and hardness values were compared with those of pure polyurethane. The hardness measurements were carried out according to the Shore D scale. While the tensile strength and modulus of elasticity of the pure polyurethane materials were 20.94 MPa and 0.601 GPa, the values of the polyurethane nanocomposite materials reinforced with 0.35% MWCNT was 23.21 MPa and 1.077 GPa. The reinforced MWCNTs increased these values by 11.0% and 0.79, respectively. In addition, fractured surfaces were examined using a scanning electron microscope (SEM) to determine the damage mechanisms.

Anahtar Kelimeler

• MWCNT
• Polyurethane
• Nanocomposite
• Mechanical properties
• Damage mechanisms

Kaynakça

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