Studies on the effects of kaolin filler concentrations on the thermal and mechanical performance of furan–lignin foam formulations

Alaba Joseph Adebayo; Ilemobayo Ifedayo Oguntimehin

doi:10.46481/jnsps.2026.3355

Authors

Alaba Joseph Adebayo
[email protected]

Department of Chemical Sciences, Olusegun Agagu University of Science and Technology, P.M.B. 353, Okitipupa, Nigeria
Ilemobayo Ifedayo Oguntimehin
Department of Chemical Sciences, Olusegun Agagu University of Science and Technology, P.M.B. 353, Okitipupa, Nigeria

Keywords:

Kaolin, Furan–lignin foam, Bio-based foam, Thermal stability, Compressive strength

Abstract

Plant-based furan--lignin foams (FLFs) offer several advantages over petroleum-based foams, including abundant and affordable feedstocks, fire resistance, thermal performance, environmental compatibility, and renewable origin. In this work, rigid plant-derived furan--lignin foams were synthesized by incorporating kaolin filler into the formulation. The effects of kaolin concentration (0, 0.5, 1.0, 1.5, 2.0, and 2.5 g, corresponding to foams KF1--KF6) on the thermal and mechanical properties of the foams were evaluated. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), density measurement, compressive strength testing, thermogravimetric analysis (TGA), and derivative thermogravimetry (DTG) were used to characterize the kaolin-reinforced furan--lignin bio-based foams. The foams were high-density materials, and KF4, containing 1.5 g of kaolin, showed the best overall performance, with a density of 0.256 gcm³ and a compressive stress of 26.63 MPa. KF4 also exhibited promising thermal stability up to about 588.39 ^oC and a residue content of 19.48% at 863 ^oC. SEM analysis showed both open- and closed-cell morphologies, with cell sizes ranging from 40 to 250 \mu\m. The results indicate that optimum kaolin loading can enhance the mechanical efficiency and thermal stability of rigid bio-based foams.

Dimensions

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