Biobased Polyamide 4,36 Thermoplastic Elastomer and its Cellulose Nanocomposites

Abstract The search for fossil fuel‐based polymer alternatives has attracted significant attention over the past few decades. A biobased polyamide elastomer, namely PA4,36, is synthesized through a facile polycondensation of fatty acid‐based monomer and 1,4‐butanediamine. The chemical structure and molecular weight distribution of the polymer are characterized by Fourier infrared spectroscopy and gel permeation chromatography. PA4,36 displays a medium hardness (Shore A/Shore D = 97/50), a high stretchability (1116%), ease of melt processing, and hydrophobicity. The introduction of cellulose nanocrystals (CNCs) to the elastomer reduces the melting temperature and crystallization temperature due to the disturbance of CNCs on polymer crystallization, and influences its thermal degradation. It improves the glass transition temperature by up to 5.1 °C because of the restriction of the molecular mobility of the polymer by CNCs. It increases the storage modulus significantly from 1.5 GPa at 25 °C for neat PA4,36, to up to 10.8 GPa for the nanocomposite with 10 wt.% CNCs. The biobased elastomer and its CNC nanocomposites can be promising alternatives to some fossil fuel‐based elastomers with medium hardness.