Biobased chiral semi-crystalline or amorphous high-performance polyamides and their scalable stereoselective synthesis

Abstract

The use of renewable feedstock is one of the twelve key principles of sustainable chemistry. Unfortunately, bio-based compounds often suffer from high production cost and low performance. To fully tap the potential of natural compounds it is important to utilize their functionalities that could make them superior compared to fossil-based resources. Here we show the conversion of (+)-3-carene, a by-product of the cellulose industry into ε-lactams from which polyamides. The lactams are selectively prepared in two diastereomeric configurations, leading to semi-crystalline or amorphous, transparent polymers that can compete with the thermal properties of commercial high-performance polyamides. Copolyamides with caprolactam and laurolactam exhibit an increased glass transition and amorphicity compared to the homopolyamides, potentially broadening the scope of standard polyamides. A fourstep one-vessel monomer synthesis, applying chemo-enzymatic catalysis for the initial oxidation step, is established. The great potential of the polyamides is outlined.

β‐Pinene‐Derived Polyesteramides and Their Blends: Advances in Their Upscaling, Processing, and Characterization

“…In addition, PPA is difficult to handle and due to the additional step of quenching also not very convenient. [ 23 ]…”

“…[ 18–20 ] For this reason, terpene‐based polymers are a main aim in modern polymer chemistry, since they are not only non‐food‐based, sustainable, environmentally friendly but also have a wide range of structures and property profiles. [ 21–28 ]…”

From terpenes to sustainable and functional polymers

“…The syntheses of both monomers were scaled up to molar amounts. 180 In the same work, the crystal structure of poly-k5 was reported, and this polyamide was shown to have a T g and T m of 105 and 280°C, respectively.…”

Sustainable Chemistry – An Interdisciplinary Matrix Approach

“…Hence, the respective values for PA6 ( T g 50 °C and T m 60 °C) were significantly surpassed [29c] . Moreover, the synthesis of PA6‐ and PA12‐type copolymers using caprolactam or laurinlactam with either (3 R )‐caranlactam or the (3 S )‐caranlactam at different ratios resulted in a set of transparent amorphous copolymers indicating the potential of the new monomer class for tuning optical properties of polyamides in a broader context [29b,d] . These examples demonstrate how a yet underexploited raw material could be used to introduce disruptive molecular pattern into a class of established polymers and can be a game changer because of its natural origin.…”