In this study, blends of polypropylene (PP) with polylactic acid (PLA) and polyhydroxybutyrate (PHB) biopolymers and wood flour were prepared, and Fuzzy and Grey Multi-Criteria Decision-Making (MCDM) methods were used to determine the blends with the best properties. The physical, mechanical, thermal, structural, and morphological properties of the composites were determined. The obtained results showed that PLA and wood flour generally improved the mechanical properties of the PP composites. However, wood flour did not exhibit a homogeneous distribution in the matrix. The density of the composites generally increased with the addition of both PLA and PHB. X-ray diffraction analysis showed that the crystallinity index of the composites generally decreased due to the low crystallinity of biopolymers. Thermal stability did not change with the addition of PLA and PHB, but the addition of wood increased thermal stability. According to the MCDM analysis, both Fuzzy and Grey results were similar.

This study investigated the mechanical properties of blends and their nanocomposite blends (BNCs) of polyhydroxybutyrate (PHB) and polylactic acid (PLA) at different loadings (0.5, 1, and 2%) of cellulose nanofibrils (CNF) and nano titanium dioxide (n–TiO2), and parameter optimisation of the BNCs was conducted using a statistical technique such as Taguchi-grey relational and regressional analysis. The results showed that adding PLA to PHB increased the mechanical properties of the blends, and the mechanical properties increased more with the high loading of PLA. The reinforcement with n–TiO2 improved the mechanical properties of the blends; however, the presence of the CNF in the blends generally decreased the mechanical properties. The grey relational analysis showed that the best BNCs were 75% PHB /25% PLA with 0.5% CNF. However, Taguchi analysis found that 75% PHB / 25% PLA with 2% n–TiO2 has the best mechanical properties.

Çalışmada, Türkiye kâğıt ürünleri, orman ürünleri ve mobilya sektörlerinde yer alan on beş işletmenin finansal performansını belirlemek için Entropi temelli PROMETHEE yöntemiyle bir değerlendirme sistemi oluşturulmuş, değerlendirme göstergelerine göre işletmelerin Borsa İstanbul (BIST) hisselerinin pandemi dönemi ve öncesi mevcut gelişmelere gösterdikleri tepki yansıtılmaya çalışılmıştır. Finansal performans oranlarını kapsayan on bir kriter pandemi ve öncesi yıllar için birlikte değerlendirilmiştir. Ağırlıklandırılmış kriterlere göre hisselerin tercih sıralaması oluşturulmuştur. Bu sıralamada ALKA (K1) ve SUMAS (OM4) hissesinin pandemi ve öncesi dönemde en iyi performansı gösterdiği görülmüştür. Genel olarak orman endüstri sektöründe faaliyet gösteren firmaların pandemiden minimum etkilendiği tespit edilmiştir.

The aim of the paper is to determine the effects of nano fillers such as cellulose nanofibrils and nano-scaled titanium dioxide on some properties of polyhydroxybutyrate and polylactic acid biopolymers; it also determined the selection of biopolymer nanocomposites with the optimum properties by using multicriteria decision-making methods such as multi-attribute utility theory, simple additive weighting, and weighted aggregated sum product assessment. Test results showed that the mechanical properties of the biopolymer nanocomposites generally increased with the addition of the cellulose nanofibrils and nano-scaled titanium dioxide. However, the addition of nano-scaled titanium dioxide decreased the tensile modulus. The addition of the cellulose nanofibrils had a higher effect on the tensile and flexure modulus of elasticity than the addition of the nano-scaled titanium dioxide. Thermal properties were generally found to improve with the addition of the cellulose nanofibrils and nano-scaled titanium dioxide. Melting temperature (T_m) generally decreased with the addition of the nano fillers. The scanning electron microscopic images showed that the nano fillers were dispersed as white dots in the biopolymer matrix. After accelerated weathering and decay test, outdoor performance of the biopolymer nanocomposites was found to be improved with the addition of the nano fillers. Multicriteria decision-making methods were conducted to determine the biopolymer nanocomposites having the optimum properties, and all the methods showed that the best biopolymer nanocomposites was polylactic acid with 1% cellulose nanofibrils.