Reinforcement of bio‐based network polymer with wine pomace

Abstract Polymer materials prepared using renewable resources such as agricultural and food wastes would lead to a sustainable society. Our target was a synthesis of fiber‐reinforced network polymer derived from citrus oil and wine pomace. Lignocellulose nanofiber (LCNF) was successfully prepared from wine pomace by mechanical fibrillation using disk mill grinder under wet condition, followed by freeze‐drying. The resultant LCNF with coarse powder‐like (the untreated LCNF) enabled to reinforce bio‐based network polymer derived from limonene oxide even though heterogeneously dispersed LCNF was observed in the polymer matrix. Polymer/LCNF composite material with almost homogeneously dispersed LCNF was obtained using LCNF prepared from alcohol‐exchange process prior to freeze‐drying (the alcohol‐exchanged LCNF). Tensile strength of the network polymer reinforced by 2% of alcohol‐exchanged LCNF was around 3.2 times higher than that of the polymer without any LCNF. Dynamic mechanical analysis measurement exhibited that cross‐link density of the network polymer reinforced by 2% of alcohol‐exchanged LCNF was around 1.4 times higher than that of the neat polymer. It is noted that the cross‐linker for bio‐based network polymer, branched polyethyleneimine, likely acted as a dispersing agent for LCNF.