Linalool Derivatives for Natural Product-Based 4D Printing Resins

Abstract

The use of green alternatives to petrochemicals from renewable feedstocks is of great interest globally, especially within additive manufacturing efforts. To this end, the utilization of the terpenoid linalool is presented for photopolymer resins 3D printed using digital light processing (DLP) with thiol-ene click chemistry. Linalool derivatives are made from single-step modifications, providing multiple greener alternatives to current acrylate photopolymers, and are characterized based upon rheology, thermomechanical, and shape memory properties. The use of aliphatic and aromatic diisocyanates to produce tetra-functional monomers is demonstrated to provide tunability to the photoreactivity/gelation time as well as significantly enhancing the tensile properties (2–3 orders of magnitude increase in elastic modulus) and thermal properties (glass transition temperature increase from ∼12 °C for linalool to 75 °C for the isophorone diisocyanate-containing linalool urethane derivative) and 4D behavior, in this case shape memory response. Ultimately, the derivatives are shown to be better candidates for DLP-type 4D printing of complex prototypes, using a porous cubic structure to demonstrate the additive manufacturing potential of this simple material platform.

Biobased and degradable thiol–ene networks from levoglucosan for sustainable 3D printing

“…Due to its many advantages, thiol-ene photopolymerization is also gradually being explored in additive manufacturing resins. [25][26][27][28][29] For example, Weems et al employed naturally sourced terpenes such as linalool, limonene, and β-myrcene to synthesize a variety of photopolymerizable resins that were successfully 3D printed into porous scaffolds with a commercial tetra-functional thiol crosslinker. 28,29 The 3D printing techniques most commonly utilized to print the above reported biobased thermosets are vat photopolymerization systems such as digital light processing (DLP) and stereolithography (SLA).…”

Ring-Opening Copolymerization of Four-Dimensional Printable Polyesters Using Supramolecular Thiourea/Organocatalysis

“…Similar to other studies of polyesters and polycarbonates, the complex, 4Dprinted prototypes could be deformed into a secondary, temporary shape and "frozen" below the T g . 1,2,45,51,52 Strain fixation of the samples was found to be >99% under ambient conditions, and the strain recovery was found to exceed 99% as well (see Figure 26 in the Supporting Information). This 4D behavior was exploited for producing shape-changing 3D porous structures, and could find applications in minimally invasive medical devices, self-fitting keys or negatives, or shapechanging airfoils, among many other applications that require complex part geometries.…”

Facile and fast preparation of a tung oil-based bendable transparent electrode with mechanical strength and environmental stability via infiltration of silver nanowires into oxygen-inhibited surface layers

“…6b). 34,38,[46][47][48][49][50][51][52][53] The dynamic mechanical properties of the PAMETs were also characterized. As shown in Fig.…”