The Use of Waste from the Production of Rapeseed Oil for Obtaining of New Polyurethane Composites

Abstract

This article presents the results of research on obtaining new polyurethane materials modified by a by-product from vegetable oils industry—rapeseed cake. The chemical composition of rapeseed cake was examined. Rigid polyurethane-polyisocyanurate (RPU/PIR) foams containing a milled rapeseed cake in their composition were obtained as part of the conducted research. Biofiller was added in amount of 30 wt.% up to 60 wt.%. Effects of rapeseed cake on the foaming process, cell structure and selected properties of foams, such as apparent density, compressive strength, brittleness, flammability, absorbability, water absorption, thermal resistance and thermal conductivity are described. The foaming process of RPU/PIR foams modified by rapeseed cake was characterized by a lower reactivity, lower foaming temperature and decrease in dielectric polarization. This resulted in a slowed formation of the polyurethane matrix. Apparent density of RPU/PIR foams with biofiller was higher than in unmodified foam. Addition of rapeseed cake did not have a significant influence on the thermal conductivity of obtained materials. However, we observed a tendency for opening the cells of modified foams and obtaining a smaller cross-sectional area of cells. This led to an increase of absorbability and water absorption of obtained materials. However, an advantageous effect of using rapeseed cake in polyurethane formulations was noted. Modified RPU/PIR foams had higher compressive strength, lower brittleness and lower flammability than reference foam.

Implementation of Circular Economy Principles in the Synthesis of Polyurethane Foams

“…Cellular structure has a significant influence on the physical and mechanical properties of porous materials and thus is one of their most important properties [ 3 ]. The cell structure parameters such as cell size and cell type (closed or open) depend on the foaming process.…”

“…In order to reduce the consumption of petrochemical components in the synthesis of polyurethanes, both plant and waste fillers are also introduced. The literature describes the influence of such waste as rapeseed cake [ 3 ], basalt powder [ 4 ], thermoset polyester-glass fiber composite [ 5 ], eggshells [ 6 ], wheat straw lignin [ 7 ], brewers’ spent grain and ground tire rubber [ 8 ], buffing dust generated in leather industry [ 9 ] on the properties of polyurethane foams. Most results confirm that waste fillers can be successfully used as low-cost and environmentally friendly components for PUR foam modification.…”

Bio-Based Polyurethane Composite Foams with Improved Mechanical, Thermal, and Antibacterial Properties

“…Besides numerous favorable properties of such prepared PU composites, the application of the fillers obtained from natural sources has attracted much more attention. Incorporating bio-fillers into PU foams improves the environmentally friendly character and the mechanical properties of PU foams [29][30][31][32]. Until now, many different natural fillers have been investigated.…”

Rigid Polyurethane Foams with Various Isocyanate Indices Based on Polyols from Rapeseed Oil and Waste PET

“…Rapeseed is an especially important oil plant in the temperate climate region. Its production is showing a growing trend, both in Europe and around the world [15,16].…”