Selective Reactivity of Myrcene for Vat Photopolymerization 3D Printing and Postfabrication Surface Modification

Abstract

Biosourced materials are gaining interest industrially, but there are still limitations on the library of available materials suitable for advanced manufacturing, especially using photopolymerization-based processing techniques. Terpenes, such as myrcene, are naturally produced materials possessing structural features, specifically alkenes, that avail themselves for such techniques. Free-radical and anionic polymerization techniques were used to explore molecular architecture, such as branching, as well as molecular weight and dispersity on physical properties prior to the production of 3D printing photopolymer resins. The polymyrcene resins were printed into dogbones and mold templates for soft materials. Model reactions with monofunctional thiols were used to demonstrate the potential for postpolymerization and fabrication functionalization, accompanying a physical demonstration where the surface hydrophobicity of polymyrcene could be tuned from superhydrophobic when using an alkyl chain monothiol (greater than 100°water contact angle) to a hydrophilic surface displaying a water contact angle of less than 45°compared with that of the unmodified surface (∼60°). Tunable bulk and surface properties are a unique feature for 3D printing materials and demonstrate the potential of polymyrcene and other biosourced photopolymers to a wide range of research applications.

Anionic polymerization of dienes in ‘green’ solvents

“…with no or marginal amounts of chain coupling products (from coupling of carbanions with oxygen during the termination with methanol). Just the polymyrcene prepared in bulk exhibited a multimodal distribution, due to an as yet unidentified side reaction (see also Supporting Information) which, however, could be suppressed by lowering the reaction temperature from room temperature to 10 °C 16 . The polyisoprenes and polymyrcenes exhibited number‐average molar masses, as determined by 1 H NMR end group analyses, close to the targeted ones (Table 1), indicating a high initiator efficiency of sec ‐butyllithium for both monomers in all solvents.…”

“…Attractive renewable feedstocks are, among others, terpenes, especially monoterpenes (limonene or β‐myrcene) and also sesquiterpenes (β‐farnesene) 3–5 . Among these, β‐myrcene is a hydrocarbon 1,3‐conjugated diene, like butadiene, isoprene or β‐farnesene, which can be readily converted into a fully bio‐based elastomer by free‐radical, 6,7 controlled radical, 8,9 anionic, 10–17 cationic 18 or coordination polymerization techniques 19–21 . Polymyrcene with a high content of cis ‐1,4 units, resembling natural rubber ( cis ‐1,4‐polyisoprene), can be obtained by anionic or controlled radical polymerization, whereas highly trans ‐1,4‐ or isotactic 3,4‐polymyrcene is produced by coordination polymerization.…”

Multiacrylated Cyclodextrin: A Bio‐Derived Photocurable Macromer for VAT 3D Printing

“…Over the last years, some natural products have been (meth)acrylated or acrylated to become printable by means of SLA or DLP and most of them are specifically conceived for the preparation of hydrogels. [14][15][16][17][18][19][20][21][22][23][24][25] Among bio-derived molecules, cyclodextrins (CDs) are interesting candidates. Cyclodextrins are macrocyclic oligosaccharides obtained via the degradation of starch catalyzed by the glycosyl transferase enzyme.…”

Moving Towards a Finer Way of Light-Cured Resin-Based Restorative Dental Materials: Recent Advances in Photoinitiating Systems Based on Iodonium Salts

“…The dynamically developing printing industry is a different direction of the application of photopolymerization, which enables printing on plastic or metal materials. Moreover, in recent years, a particular emphasis has been put on the use of photopolymerization processes for 3D-printing technology [ 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 ], including stereolithography in the design and formation of three-dimensional models [ 34 ].…”