Uyumlaştırıcı Kimyasalla Güçlendirilmiş Nanoselüloz-Polipropilen Nanokompozitleri

Öz

Nanoselüloza olan talep giderek artmasıyla, bu önemli materyal uyumlaştırma kimyasallarıyla polipropilen matrikslerin güçlendirilmesinde kullanılmaktadır. Polipropilen (PP)-selüloz nanofibril (CNF) ve Fusabond Hibrit kompozitler çift vidalı ekstruder kullanılarak hazırlanmıştır. Ticari uyumlaştırıcı kimyasal PP/CNF kompozitlerinin mekanik özelliklerini iyileştirmek için kullanılmıştır. Buradaki esas zorluk, PP ve CNFs arasında uyumlu bağları oluşturmak ve polimer matriks içerisinde CNFs iyi bir dağılımını elde etmektir. Çeşitli oranlarda uyumlaştırma kimyasalı PP ve CNFs arasında yüzeyler arası bağlanmayı iyileştirmek için incelendi. Kompozitlerin FTIR karekterizasyonu polipropilen ve selüloz nanfibrilin yüzeyler arası yapışmasını belirlemek için gerçekleştirildi. Polipropilen/selüloz nanofibril kompozitlerinin mekanik ve morfolojik özellikleri üzerinde uyumlaştırıcı kimyasalın etkisi sırasıyla çekme testi, dinamik mekanik analiz ve SEM resimleriyle çalışıldı. En Kompozitlerin en iyi mekanik özellikleri, saf polipropilen (14.45 MPa, 0.570 GPa) ile karşılaştırıldığında 19.99 MPa (çekme direnci) ve yaklaşık %87 iyileşme gösteren 1.067 GPa (Young’s modülü) idi. Kırılma morfoloji incelemesi PP matriks içerisinde uyumlaştırıcı kimyasal ilavesi (0.1 wt%) durumunda CNFs’nin iyi dağılımı sağlandı. TGA sonuçları PP/CNF kompozitlerinin termal kararlılığını değiştirmediğini gösterdi, buna karşın muamelesiz PP/CNF Kompozitleriyle karşılaştırıldığında muamele edilmiş kompozitlerde hafif artış kaydedildi.

Anahtar Kelimeler

• Polipropilen,Nanoselüloz,Nanokompozitler

Nanocellulose-Polypropylene Nanocomposites Enhanced With Coupling Agent

Abstract

As the growth of the nanocellulose is evident, this important material was used to reinforce polypropylene matrix with a coupling agent. Polypropylene (PP) - cellulose nanofibril (CNF) and Fusabond hybrid composites were prepared using twin screw extrusion technique. The commercial coupling agent was used to improve mechanical properties of PP/ CNF composites. The main challenges were to obtain well-dispersed CNFs in the polymer matrix and to establish compatible linkages between the CNFs and PP. The various loadings of coupling agent were examined to improve the interfacial adhesion between PP and CNFs. FTIR characterization of the composites were performed to confirm the interfacial adhesion of polypropylene and cellulose nanofibrils. The effect of coupling agent on the mechanical and morphological properties of polypropylene/ cellulose nanofibrils hybrid composites was studied by tensile testing, dynamic mechanical analysis, and SEM images, respectively. The best mechanical properties of the composite were 19.99 MPa (tensile strength), 1.067 GPa (Young's Modulus), which represented about 87% improvement, respectively, compared to that of pure polypropylene (14.45MPa, 0.570 GPa). Fracture morphology examination indicated good dispersion of CNFs in the PP matrix was achieved in the case of loading coupling agent (0.1 wt %). TGA results show that thermal stability of PP/CNF composites did not change much but slightly increased in the treated composites compare to that of the untreated PP/CNF composite.

Keywords

• Polypropylene,Nanocellulose,Nanocomposites

Kaynakça

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