Novel Biobased Polyamide Thermoplastic Elastomer with Medium Hardness

Abstract

Thermoplastic elastomers (TPEs) are useful in various engineering and healthcare applications. A new fully biobased polyamide TPE (PA36,9) with medium hardness is reported. The elastomer is synthesized using a fatty dimer amine and azelaic acid, via one-pot melt condensation polymerization. The resulting elastomer shows a melting temperature of 83.6 °C, a medium hardness (Shore A/Shore D = 90/35), a large elongation at break (1220%), good resilience, and impact resistance, while maintaining high tensile strength (31.8 MPa), low density (0.93 g cm −3 ), and hydrophobicity. The chemical structure of the repeating unit, together with the molecular weight and molecular weight distribution, of the polymer governs the properties of the resulting polyamide, which differ from those of conventional aliphatic polyamides. This biobased polyamide elastomer is a promising candidate to substitute some fossil fuel-based medium-hardness TPEs for applications, such as insulation, sealing, automotives, and construction.

Wholly Biobased Polyamide Thermoplastic Elastomer‐Cellulose Nanocomposites

“…The hysteresis ratio ( h r ) is calculated by the ratio of the energy dissipation ( e d ) to the energy absorption (i.e., the area below the loading curve, e a ), i.e., Equation () [ 43 ] $$\begin{equation}{h_{\rm{r}}} = \frac{{{e_{\rm{d}}}}}{{{e_{\rm{a}}}}}\end{equation}$$…”

“…[37,41] A higher energy dissipation is beneficial for these elastomer nanocomposites to be used in shock absorption applications. [42] The hysteresis ratio (h r ) is calculated by the ratio of the energy dissipation (e d ) to the energy absorption (i.e., the area below the loading curve, e a ), i.e., Equation (1) [43]…”

Wholly Biobased Polyamide Thermoplastic Elastomer‐Cellulose Nanocomposites

“…[42] The hysteresis ratio (hr) is calculated by the ratio of the energy dissipation (ed) to the energy absorption (i.e. the area below the loading curve, ea), i.e., equation (1) [43] .…”

Biobased Polyamide 4,36 Thermoplastic Elastomer and its Cellulose Nanocomposites

“…Recently, we prepared a couple of novel wholly biobased polyamide elastomers, PA36,36 [ 7 ] and PA36,9 [ 8 ] PA36,36 is an amorphous elastomer that shows excellent hydrophobicity, super stretchability (up to 2300%), a high toughness (17.3 MJ m −3 ), low hardness (Shore A/Shore D = 16/6), low glass transition temperature ( T g = 3.3 °C), and remarkable autonomous self‐healing efficiency. [ 7 ] PA36,9 is a semi‐crystalline elastomer that has a high tensile strength (31.8 MPa), large elongation at break (1220%), medium hardness (Shore A/Shore D = 90/35), T g of 17.6 °C, and a melting temperature ( T m ) of 83.6 °C, while maintaining high hydrophobicity.…”

“…[ 7 ] PA36,9 is a semi‐crystalline elastomer that has a high tensile strength (31.8 MPa), large elongation at break (1220%), medium hardness (Shore A/Shore D = 90/35), T g of 17.6 °C, and a melting temperature ( T m ) of 83.6 °C, while maintaining high hydrophobicity. [ 8 ] Despite excellent properties, these polyamide elastomers have been reinforced with cellulose nanocrystals (CNCs) to broaden their applications. [ 9 ] CNCs have a high aspect ratio (length 50–500 nm and diameter 3–5 nm), and high crystallinity (54–88%).…”