A Comparative Study on the Mechanical Properties of Different Natural Fiber Reinforced Free-Rise Polyurethane Foam Composites

Abstract

The goal of this study was to improve tailored mechanical properties of foam by incorporating different filler types. Flexible polyurethane foam thermosets with varying wt % of natural fibers were tested and characterized according to their mechanical, morphological, and thermal properties. The fillers used included lignin, chitin, chitosan, hazelnut shells, and polysaccharide, and the results were investigated to compare the effects of fillers on the foam properties. A morphological analysis showed good overall dispersion of chitin and hazelnut fillers and consequent improvements in tensile and tear strength of polyurethane foam. Additionally, these fillers helped increase resiliency while reducing foam hardness. Polysaccharide showed similar improvements in tensile results, while the tear strength decreased. However, lignin and chitosan reduced foam mechanical properties, which suggested low compatibility of these fillers (in pretreated form) with polyurethane foam. Based on the results, these fillers can be incorporated into polyurethane foam to fabricate more sustainable and ecofriendly thermoset polyurethane foams for industrial applications, such as the production of mattresses, car seats, and insulating material in construction or textile products, as well as in the cosmetic industry.

Rigid Polyurethane Biofoams Filled with Chemically Compatible Fruit Peels

“…The SEM micrographs ( Figure 4 ) also suggest a good chemical affinity of the fillers in the RPUF cellular structure since no agglomerates were founded. Similar behaviors have been found in the literature for other chemically compatible fillers, such as fillers based on different polysaccharides [ 5 , 11 , 25 ]. These later PU systems again seem to be affected by urethane linkages between NCO groups from the p-MDI and OH groups from the bergamot peel.…”

“…Cellulose-based fibers, micro/nanofibers, nanocrystals, paper and powder, wood flour, lignin particles, natural macro-fibers, silica-based micro/nanoparticles, and domestic and industrial solid residues are some already studied fillers for RPUF [ 7 , 8 , 9 , 10 ]. These vegetable resources provide a higher cost benefit compared to synthetic fibers and also represent an increase in sustainable appeal [ 11 ]. The main advantages conferred by the introduction of natural fillers into RPUF include increases in thermal, mechanical, and hygroscopic properties and biodegradability, as well as decreases in consumption of oil-based raw materials, emissions of greenhouse gas, and production costs [ 5 ].…”

Fabrication strategy for long‐chain branched polypropylene foams with high resilience and compressive strength

“…The excellence resilience performance of the material after deformation is conducive to the repeated use of the material. Therefore, rebound material is widely used in safety helmet, 1,2 car seats, 3 and mattresses and pillows 4,5 . In oil–water separation foam materials, 6–8 where the oil is desorbed from the foam by compressive deformation.…”

“…Therefore, rebound material is widely used in safety helmet, 1,2 car seats, 3 and mattresses and pillows. 4,5 In oil-water separation foam materials, [6][7][8] where the oil is desorbed from the foam by compressive deformation. As a result, the excellence resilience performance can extend the life of the foam materials.…”

A fluorescent polyurethane foam based on rhodamine derivative as Fe(III) sensor in pure water

“…Fluorescent molecules can be easily introduced into the PU chains through chemical bonding during the synthesis, which can limit their migration during application 25 . Particularly, PU foam has the unique property of adjustable pore structure, which provides a large specific surface area, 26–28 increasing the contact area between metal ions and fluorophores. Thereby, this can effectively improve the sensitivity of fluorescent chemical sensors.…”