Mesut KANDEMİR, İdris KARAGÖZ, Harun SEPETÇİOĞLU

Çekirdekleştirici Ajanın Enjeksiyonla Kalıplanmış İzotaktik Polipropilenin Mekanik ve Kristalizasyon Davranışı Üzerindeki Etkilerinin Deneysel Olarak İncelenmesi

Bu çalışmada, talk (magnezyum-silikat-monohidrat/3MgO.4SiO2.H2O) çekirdekleştirici ajanın (NA) izotaktik-polipropilenin (i-PP) termal ve mekanik özellikleri üzerindeki etkisi eriyik harmanlama yöntemi kullanılarak %0,5 ile %5 arasında değişen katkı oranlarına göre incelendi. Sonuçlar, NA/i-PP'nin saf i-PP'ye oranla önemli ölçüde geliştirilmiş mekanik performans sergilediğini gösterdi. Ek olarak, saf i-PP'nin erime ve kristalleşme davranışı üzerindeki NA konsantrasyonunun etkisi de DSC eğrileri aracılığıyla analiz edildi. NA konsantrasyonu arttıkça i-PP'nin gerilme ve eğilme özellikleri arttı. Ayrıca, taramalı elektron mikroskobu, NA/i-PP ve i-PP matrisi arasında kırılma yüzeyinde önemli bir fark olduğunu ortaya çıkardı. Sonuç olarak, bu çalışmada kullanılan NA'nın (talk) i-PP için iyi bir NA olduğu, ürünün mekanik ve termal özelliklerini iyileştirdiği, kristalleşme özelliklerini ve mikro yapıyı etkilediği ve kalıp çevrim süresini azalttığı belirlendi. Bunların yanı sıra, talk ile i-PP matrisi arasında arayüz özelliklerini iyileştirebilecek çeşitli katkı maddelerinin kullanılmasının, mekanik ve termal özellikleri çok daha yüksek olan yeni i-PP tasarımına alternatif bir yaklaşım olması beklenmektedir.

Anahtar Kelimeler:

polipropilen, kristalizasyon, çekirdekleştirici ajan, mekanik özellikler

Experimental Investigation of Effects of the Nucleating Agent on Mechanical and Crystallization Behavior of Injection-Molded Isotactic Polypropylene

In this study, we investigated the effect of talc (magnesium-silicate-monohydrate/3MgO.4SiO2.H2O) nucleating agent (NA) on the thermal and mechanical properties of isotactic-polypropylene (i-PP) at loadings ranging from 0.5 to 5% by weight using the melt compounding method. The results demonstrated that NA/i-PP exhibited significantly improved mechanical performance compared to neat i-PP. In addition, the influence of the concentration of the NA on the melting and crystallization behavior of neat i-PP was also analyzed through DSC curves. The tensile and flexural properties of i-PP enhanced as NA concentration increased. Furthermore, scanning electron microscopy revealed that there is a significant difference in the fracture surface between the NA/i-PP and the i-PP matrix. Consequently, it was determined that the NA (talc) used in this study was a good NA for i-PP, improved the mechanical and thermal properties of the product, affected the crystallization properties and the microstructure, and reduced the mold cycle time. Besides these, the use of various additives between talc and i-PP matrix that can improve interface features are expected to be an alternative approach to the new i-PP design with much higher mechanical and thermal properties.

Keywords:

polypropylene, crystallization, nucleating agent, mechanical properties polypropylene, crystallization, nucleating agent, mechanical properties,

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