title: Azide/alkyne-"click"-reactions of encapsulated reagents: toward self-healing materials.
abstract: The successful encapsulation of reactive components for the azide/alkyne-"click"-reaction is reported featuring for the first time the use of a liquid polymer as reactive component. A liquid, azido-telechelic three-arm star poly(isobutylene) (M(n) = 3900 g · mol⁻¹) as well as trivalent alkynes were encapsulated into micron-sized capsules and embedded into a polymer-matrix (high-molecular weight poly(isobutylene), M(n) = 250,000 g · mol⁻¹). Using (Cu(I)Br(PPh₃)₃) as catalyst for the azide/alkyne-"click"-reaction, crosslinking of the two components at 40 °C is observed within 380 min and as fast as 10 min at 80 °C. Significant recovery of the tensile storage modulus was observed in a material containing 10 wt.-% and accordingly 5 wt.-% capsules including the reactive components within 5 d at room temperature, thus proving a new concept for materials with self-healing properties.
authors: Chair of Macromolecular Chemistry, Faculty of Natural Sciences II, Institute of Chemistry, Martin-Luther-University Halle-Wittenberg, von-Danckelmannplatz 4, D-06120 Halle, Germany.
authors: Maria
authors: M
authors: Gragert
authors: Marlen
authors: M
authors: Schunack
authors: Wolfgang H
authors: WH
authors: Binder
mesh_terms: D000480:Alkynes / Q000737:chemistry*; D001386:Azides / Q000737:chemistry*; D002384:Catalysis; D057930:Click Chemistry; D003500:Cyclization; D015394:Molecular Structure; D011090:Polyenes / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D000480:Alkynes; D001386:Azides; D011090:Polyenes; D011108:Polymers; C008967:polyisobutylene