Biomass Origin Waste as Activators of the Polyurethane Foaming Process

Abstract

Rigid polyurethane foams (RPUFs) are characterized by their excellent viable properties; thus, these materials can be successfully used as thermal insulation materials. The main problem, the solution of which is partly indicated in this paper, is that the products for the synthesis of RPUFs are produced from petrochemicals. Due to this, the use of natural fillers in the form of waste biomass is introduced for the synthesis of RPUFs. The biodegradable biomass waste used in the RPUF production process plays multiple roles: it becomes an activator of the RPUF foaming process, improves selected properties of RPUF materials and reduces the production costs of insulating materials. The paper presents the results of the foaming process with the use of six different fillers: sunflower husk (SH), rice husk (RH), buckwheat husk (BH), sunflower husk ash (SHA), rice husk ash (RHA) and buckwheat husk ash (BHA). In all cases, composites of rigid polyurethane foam with 10 wt.% of filler were produced. New foams were compared with polyurethane materials without the addition of a modifier. Moreover, the paper presents the results of the fillers’ analysis used in the tests and the effects of the fillers’ addition as activators of the RPUF foaming process. Promising results were obtained for two of the fillers, BHA and SHA, as activators of the foaming process and confirmed by the volumetric results, where the named samples reached their maximum value in half the time compared to the remaining samples. In addition, the expansion rate for PU_10BHA was a maximum of approximately 11 cm3/s and PU_10SHA was a maximum of approximately 9 cm3/s, whereas the remaining samples showed this parameter at about 3cm3/s. During the research, the scanning electron microscopy method and infrared camera technique were used.

Optimizing the preparation parameters of eco‐friendly flexible polyurethane foams derived from a corn‐based bio‐polyol

“…Polyurethane (PU) foam has been widely used in diverse industrial applications such as automotive interior, furniture, construction, packaging, and manufacturing, due to its excellent strength, low thermal conductivity, and lightweight properties. 1 However, the conventional preparation of commercial PU foam, utilizing non-renewable petroleum-based isocyanate and polyol, leads to the emission of volatile organic compounds, resulting in environmental concerns and regulatory emission policies. 2,3 Hence, there is a growing demand for exploring and implementing sustainable bio-based materials that are eco-friendly for development and utilization.…”

Synthesis and Morphology of Flexible Polyurethane Foams Containing Neem Oil and Clove Powder

“…Generally, the structure, properties, and applications of polyurethane foams (PUF) are primarily influenced by the chemistry of the main starting materials (isocyanate and polyol), additives, and isocyanate index [11]. For instance, incorporating additives in the formulation of PUF, especially fillers, influences the kinetics of foam formation and the chemical equilibrium of the foaming reaction in addition to enhancing/reinforcing the properties of the resulting PUF composite [12,13]. To corroborate this finding, Zieleniewska et al explored using a halogen-free additive (fryol) and keratin fibres to improve the flammability of viscoelastic polyurethane foams.…”

Valorization of waste biomass for the fabrication of isocyanate-free polyurethane foams

“…are available on a large scale and low cost, and some of them were incorporated into conventional PU foam formulations. [34][35][36] However, their valorization for isocyanate-free self-foaming processes exploiting the partial cyclic carbonate decarboxylation has never been explored.…”