An Efficient Route to Well-Defined Macrocyclic Polymers via “Click” Cyclization

Abstract

Polystyrene macrocycles have been prepared from ATRP precursors by modification of the terminal bromide to an azide, followed by "click" cyclization with a pendant alkyne from the initiator. This route offers exceptional control over the size and polydispersity of the macrocyclic polymers, as well as providing tolerance to a number of functional groups.

Synthesis of a Novel Kind of Amphiphilic Graft Copolymer with Miktoarm Star-Shaped Side Chains

“…This behavior could be attributed to the smaller hydrodynamic volume of the graft copolymer with the high branched structure than the linear polymer with same molecular weight. In order to further verify this complex structure, attempts were made to hydrolyze the ester of the graft copolymer 9 using KOH in THF/CH 3 OH system, but it failed, and a similar result was reported by Laurent et al 43 In summary, an amphiphilic graft copolymer with welldefined star-shaped side chains was synthesized by the "grafting onto" method via combination of anionic polymerization and click reactions. The azide group functionality of the main chain and the alkyne group functionality at PEEGE chain end of the miktoarm star side chains were very high.…”

Synthesis of Amphiphilic Tadpole-Shaped Linear-Cyclic Diblock Copolymers via Ring-Opening Polymerization Directly Initiating from Cyclic Precursors and Their Application as Drug Nanocarriers

“…[1][2][3] It has been well-established that the topological structures and chemical composition of nonlinearshaped block copolymers can exhibit dramatic effects on the solution properties and self-assembling morphologies as compared with their linear counterpart. [4][5][6][7][8][9] It is worthy of noting that the developments of a variety of controlled radical polymerization techniques 10 such as atom transfer radical polymerization (ATRP), [11][12][13] reversible addition-fragmentation chain transfer (RAFT) polymerization, [14][15][16] and nitroxide-mediated polymerization (NMP) 17,18 have facilitated the synthesis of nonlinear-shaped polymers with varying chain architectures such as cyclic, 8,9,[19][20][21][22][23] (miktoarm) star, [24][25][26] star block copolymers, 27,28 comb, [29][30][31][32] sun-shaped, [33][34][35] H-shaped, [36][37][38] and θ-shaped 39,40 polymers. Among these nonlinear chain topologies, tadpole-shaped linearcyclic diblock copolymers [41]…”

Polyethylene‐Based Tadpole Copolymers

“…A solution of NaOH in methanol (5 mL of 1 m solution) was added to the polymer solution and the mixture was refluxed for 24 h. The cleaved polymer was precipitated in methanol, followed by washing with acetone and drying in vacuum overnight. A similar procedure was followed for the cleavage of (c-PE 813 )-b-PS 19 . [42] …”

“…[1][2][3][4][5][6][7] To date, cyclic polymers with different structures such as diblock, [8] triblock terpolymer, [9] eight-shaped, [10] and tadpole copolymers [11][12][13][14][15] have been synthesized either by end-to-end linking or ring-expansion process. [16][17][18][19][20] Among them, tadpole homo/copolymers consisting of a ring polymer as a head and one linear polymer as a tail, are very interesting for rheology and self-assembly studies, since they combine two topologies in the same molecule.…”