Titanat bağlayıcı ajanının odun tozu katkılı sert poliüretan köpük kompozitlerin özelliklerine etkisinin araştırılması
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Tarih
2024
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Yayıncı
Bursa Teknik Üniversitesi, Lisansüstü Eğitim Enstitüsü
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
Poliüretan, kauçuğa alternatif bir malzeme olarak keşfedilmiş olup, iki ana madde olan poliol ve izosiyanatın reaksiyonuyla oluşmaktadır. Zaman içerisinde poliüretan malzemeler çeşitlenmiş ve özellikle yalıtım amacıyla sert poliüretan köpük sistemleri (PU) üretilmiştir. Genel yapılarında köpük hücreleri kapalıdır. Kimyasal yapılarından dolayı yanma dirençleri düşük ve termal bozunma eğilimleri yüksek olduğundan uygulama alanları sınırlıdır. Soğutucular, iç ve dış yalıtım gibi amaçlarla kullanılabilirler. Bu çalışmada PU köpük kompozit yapı içerisinde en az bir biyomalzeme kullanarak biyokompozit malzeme üretilmesi amaçlanmaktadır. Bu anlamda, odun tozu katkılı sert poliüretan köpük kompozit elde edilmesi planlanmaktadır. Bu amaçla, odun tozu olarak ıhlamur, kayın ve orta yoğunluklu lifli levha (MDF) tozlarının kullanılması hedeflenmiştir. Ayrıca, elde edilen köpük kompozit yapıların özellikle daha yüksek mekanik özelliklere sahip olabilmesi açısından titanat (Ti) bağlayıcı ajan ile odun tozları kaplanacaktır ve böylece çift aşamalı üretim gerçekleştirilecektir. Titanat bazlı bağlayıcı maddeler, titanyum içeren organometalik ara yüzey kimyasallarıdır ve polimerik kompozitleri güçlendirmek için kullanılırlar. Kompozitlerin mekanik özelliklerini geliştirirler ve kompozitlerin nem direncini arttırabilirler. Elde edilen ürünlerin kimyasal yapıları, mikroyapıları, ısıl özellikleri ve mekanik özellikleri incelenecektir. Elde edilen numunelerin test sonuçları değerlendirildiğinde FTIR sonuçlarında titanat ile kaplanmış ıhlamur, kayın ve MDF tozu katkılı PU köpük kompozitlerin spektrumları katkısız sert PU köpük ile benzer pikler sergilediği görülmektedir. PU köpüğe eklenen katkıların köpük ile etkileşime girmediği anlaşılmaktadır. Ayrıca, kaplama yapılmadan eklenen ıhlamur ve kayın tozları PU köpük yapısını daha iletken hale getirirken, titanat kaplı ıhlamur ve kayın tozlarının PU köpük yapısını daha yalıtkan hale getirmiştir. Buna karşın, MDF katkısı PU köpük yapısını daha iletken hale getirmiştir. İlaveten, ıhlamur katkılı PU köpük numunelerin çekme değerleri incelendiğinde yapıya katkı eklendiğinde değerlerde düşüş olduğu, kopma uzaması değerinde ise ağırlıkça %20 ve %30 numunelerde artış gözlenmiştir. Özellikle, titanat kaplı ıhlamur katkılı PU köpük numunelerde kopma uzaması değerindeki artış ağırlıkça %20 ve %30 numunelerde önemli ölçüde yükselmiştir. Kayın katkılı PU köpük numunelerin çekme değerleri incelendiğinde yapıya kaplamasız katkı eklendiğinde değerlerde %5-%20 bandında artış olduğu gözlenmiştir. Kopma uzaması değerinde ise kaplamasız ve Ti kaplı kayın katkılı numunelerde özellikle ağırlıkça %20 ve %30 numunelerde belirgin oranda artış gözlenmiştir. MDF katkılı SPK numunelerde yapıya kaplamasız katkı eklendiğinde değerlerde ağırlıkça %5 katkı oranında artış olduğu ancak katkı miktarı arttıkça düşüş yaşandığı, Ti kaplamada kaplamasız numunelere göre çekme değerlerinde artış olduğu gözlenmiştir. Katkılar genel olarak katkısız PU köpüğe kıyasla hücre çapının düşmesine sebep olmuştur ancak Ti kaplamalı numunelerde kaplamasız numunelere oranla çapının daha stabil kaldığı görülmüştür. Köpük içerisine eklenen katkılar çekirdeklenme noktası olarak görev almış ve bu nedenle oluşan gözenek sayısının artmasına sebep olmuştur.
Polyurethane was first discovered as a result of an alternative material to rubber. These materials were formed by the reaction of two main substances, polyol and isocyanate. Rigid polyurethane foam systems (PU) are produced for insulation. In their general structure, foam cells are closed. Due to their chemical structure, they have low burning resistance and high tendency to thermal decomposition, therefore their application areas are limited. They can be used such as coolers, interior and exterior insulation. In this study, it is aimed to produce biocomposite material by using at least one biomaterial in the rigid polyurethane foam composite structure. In this sense, it is planned to obtain rigid polyurethane foam composite with wood powder additives. For this purpose, it is aimed to use linden, beech and medium density fibreboard (MDF) powders as wood powder. In addition, wood powders will be coated with titanate (Ti) coupling agent in order to ensure that the resulting foam composite structures have higher mechanical properties, and thus two-stage production will be carried out. Titanate-based agents are titanium-containing organometallic interfacial chemicals and are used to strengthen polymeric composites. They improve the mechanical properties of composites and can increase the moisture resistance of composites. The chemical structures, microstructures, thermal properties and mechanical properties of the resulting products will be examined. When the test results of the samples obtained are evaluated, it is seen that the FTIR spectra of linden, beech and MDF powder filled PU foam composites coated with titanate in the FTIR results exhibit similar peaks as the pure PU foam. It is understood that the additives introduced to PU foam do not interact with the foam. Linden and beech powders added without coating made the PU foam structure more conductive, but titanate-coated linden and beech powders made the PU foam structure more insulating. On the other hand, MDF additive made the PU foam structure more conductive. Furthermore, when the tensile values of linden-added PU foam samples were examined, a decrease was observed in the values when fillers were added to the structure, and an increase in the elongation at break value was observed in the samples with 20% and 30% by weight. Especially, the increase in the elongation at break value for titanate-coated PU foam samples is noticeably higher in 20% and 30% by weight filled samples. When the tensile values of PU foam samples with beech filler were examined, it was observed that there was an increase in the values in the range of 5%-20% in the case of uncoated fillers filled to the structure. A significant increase in the elongation at break value was observed for uncoated and titanate-coated samples, especially in the case of 20% and 30% by weight filled samples. It was observed that in MDF reinforced PU foam samples, when uncoated filler was added to the structure, there was an increase in the values for the sample filled at 5% by weight, but as the amount of filler increased, a decrease was observed and compared to the uncoated samples in Ti coating, there was an increase in the tensile values. Fillers generally caused the cell diameter to decrease compared to pure PU foam, but the cell diameter remained more stable for titanate-coated samples compared to uncoated samples. The fillers added into the foam served as nucleation points and therefore caused an increase in the number of cells formed.
Polyurethane was first discovered as a result of an alternative material to rubber. These materials were formed by the reaction of two main substances, polyol and isocyanate. Rigid polyurethane foam systems (PU) are produced for insulation. In their general structure, foam cells are closed. Due to their chemical structure, they have low burning resistance and high tendency to thermal decomposition, therefore their application areas are limited. They can be used such as coolers, interior and exterior insulation. In this study, it is aimed to produce biocomposite material by using at least one biomaterial in the rigid polyurethane foam composite structure. In this sense, it is planned to obtain rigid polyurethane foam composite with wood powder additives. For this purpose, it is aimed to use linden, beech and medium density fibreboard (MDF) powders as wood powder. In addition, wood powders will be coated with titanate (Ti) coupling agent in order to ensure that the resulting foam composite structures have higher mechanical properties, and thus two-stage production will be carried out. Titanate-based agents are titanium-containing organometallic interfacial chemicals and are used to strengthen polymeric composites. They improve the mechanical properties of composites and can increase the moisture resistance of composites. The chemical structures, microstructures, thermal properties and mechanical properties of the resulting products will be examined. When the test results of the samples obtained are evaluated, it is seen that the FTIR spectra of linden, beech and MDF powder filled PU foam composites coated with titanate in the FTIR results exhibit similar peaks as the pure PU foam. It is understood that the additives introduced to PU foam do not interact with the foam. Linden and beech powders added without coating made the PU foam structure more conductive, but titanate-coated linden and beech powders made the PU foam structure more insulating. On the other hand, MDF additive made the PU foam structure more conductive. Furthermore, when the tensile values of linden-added PU foam samples were examined, a decrease was observed in the values when fillers were added to the structure, and an increase in the elongation at break value was observed in the samples with 20% and 30% by weight. Especially, the increase in the elongation at break value for titanate-coated PU foam samples is noticeably higher in 20% and 30% by weight filled samples. When the tensile values of PU foam samples with beech filler were examined, it was observed that there was an increase in the values in the range of 5%-20% in the case of uncoated fillers filled to the structure. A significant increase in the elongation at break value was observed for uncoated and titanate-coated samples, especially in the case of 20% and 30% by weight filled samples. It was observed that in MDF reinforced PU foam samples, when uncoated filler was added to the structure, there was an increase in the values for the sample filled at 5% by weight, but as the amount of filler increased, a decrease was observed and compared to the uncoated samples in Ti coating, there was an increase in the tensile values. Fillers generally caused the cell diameter to decrease compared to pure PU foam, but the cell diameter remained more stable for titanate-coated samples compared to uncoated samples. The fillers added into the foam served as nucleation points and therefore caused an increase in the number of cells formed.
Açıklama
Anahtar Kelimeler
Kayın odunu, Beech wood, Kompozit malzemeler, Composite materials, Polimer kompozitler, Polymer composites, Poliüretan köpük, Polyurethane foam, Rijit poliüretan, Rigid polyurethane
