Properties of Biobased Rigid Polyurethane Foams Reinforced with Fillers: Microspheres and Nanoclay

Abstract

The effect of incorporating 1–7% microsphere and nanoclay fillers on the physical properties of polyurethane (PU) foams containing 15% soybean oil-based polyol was investigated. Increasing filler percentage reduced the PU foam density. The compressive strength of PU foams decreased slightly when increasing the microsphere content from 1 to 3% and then increased. At 7% microsphere content, the foams displayed the same compressive strength as the control foams made from 100% petroleum polyol. For PU foams reinforced with nanoclay, their compressive strength changed little from 1 to 5%, but decreased at 7% due to a lower density and weaker matrix structure. Foams containing 5 to 7% microspheres or 3 to 7% nanoclay had density-compressive strength comparable or superior to the control. Foams reinforced with fillers had more cells and smaller cell size than foams made from 15% soy-polyol but without fillers. During the foaming process, the maximal temperatures reached by PU foams were not affected by the presence of 1 to 7% of microspheres or nanoclay, but slightly lower than the control. In addition, foams with fillers displayed roughly the same thermal conductivity as soy-polyol based foams without fillers.

Characterization of polyurethane foams prepared from liquefied sawdust by crude glycerol and polyethylene glycol

“…The PU foams were kept for 48 h at room temperature before cutting and further testing. Foam 1 as a foam obtained from polyol of sawdust liquefaction by CG and other foams (2,3,4) as foams obtained from polyol of …”

“…Today, these foams are produced from polymeric methylene diphenyl diisocyanate (polymeric MDI) and either polyether or polyester polyols that are petro-chemical derived chemicals. Increasing cost of petrochemical feed stocks, concern of future shortage in petroleum supplies and public desire for environmentally friendly green products have encouraged many research projects to explore the polymers from sustainable and renewable resources [3]. Interest in the use of lignocellulosic biomass for preparing PU foams is increasing now.…”

Nanoki̇l Ve Kabaran Alev Geci̇kti̇ri̇ci̇ İlavesi̇ni̇n Ri̇ji̇t Poli̇üretan Köpük Malzemeleri̇n Isil Bozunma Ve Yanma Davranişlarina Etki̇leri̇ni̇n İncelenmesi̇

“…Ayrıca, artan nanokil ile hücre duvarlarında kalması gereken partiküllerin hücre duvarlarını yıkarak hücre boyutunun artmasına da sebep olduğu bilinmektedir [37]. Köpük malzemelerin ısı iletim katsayılarının zamana bağlı olarak artış gösterdiği bilinmektedir [37,38].…”

“…Köpük malzemelerin ısı iletim katsayılarının zamana bağlı olarak artış gösterdiği bilinmektedir [37,38]. Üretilen köpük malzemelerde genel olarak yaklaşık 50 gün içerisinde belirli artışlar olur iken, 50'inci günden sonra artış oranı oldukça düşük seviyelere inmiştir.…”

“…Poliüretan köpük malzeme içerisine dolgu maddesi olarak ilave edilen kil oranının artmasıyla köpük malzemenin hücre duvarları arasına yerleşen kil nedeniyle hücre duvarları daha zayıf ve ince hale gelerek daha kolay kırılmaktadır. Bunun sonucunda artan dolgu oranıyla kapalı hücre sayısı düşmekte ve köpük malzemenin ısı iletim katsayısında artışa neden olmaktadır [37]. …”