Atom Transfer Radical Polymerization of Solketal Acrylate Using Cyclohexanone as the Solvent

Abstract

Summary: Solketal acrylate (SA) was homopolymerized by atom transfer radical polymerization (ATRP) using CuBr/N,N,N′,N″,N″‐pentamethyldiethylenetriamine as the catalyst and cyclohexanone as the solvent with controlled molecular weights and low polydispersities. The prepared bromine‐terminated homopolymers, PSA, were used as macroinitiators to initiate polymerization of tert‐butyl acrylate (tBA) under similar ATRP conditions to produce diblock copolymers, PSA‐b‐PtBA, with controlled molecular weights and low polydispersities. ATRP of SA using bromine‐terminated PtBA as the macroinitiator was also carried out and diblock copolymers, PtBA‐b‐PSA, were obtained. The PSA block was selectively hydrolyzed by stirring for 3 h in 6 N HCl/THF (1/9, v/v) at room temperature to form a poly(glycerol monoacrylate) block. Both blocks of PSA and PtBA were hydrolyzed by stirring in anhydrous trifluoroacetic acid (TFA)/dichloromethane for 4 h, then adding water to the system and stirring for another 3 h to form corresponding diblock copolymers of glycerol monoacrylate and acrylic acid.Kinetic plot for the atom transfer radical polymerization of solketal acrylate at 90 °C.magnified imageKinetic plot for the atom transfer radical polymerization of solketal acrylate at 90 °C.

Synthesis of Y-shaped poly(solketal acrylate)-containing block copolymers and study on the thermoresponsive behavior for micellar aggregates

“…Poly(solketal acrylate) (PSA) as hydrophobic polymer can be hydrolyzed under acidic conditions to remove ketal groups and converted to water-soluble poly(2,3-dihydroxypropyl acrylate) (PHPA) bearing double hydroxyl groups in each repeating unit [24][25][26]. Compared to the intensive studies on PHPA in the field of magnetic nanocomposites and functional modification [27][28][29], PSA itself did not attract much attention but as PHPA polymer precursor.…”

Synthesis of Amphiphilic Block Copolymers Based on SKA by RAFT Polymerization

“…Scheme presents the synthetic strategy to target homo‐ and block copolymers based on SKA and NIPAAm by RAFT polymerization. Since only a few publications are currently available referring to the RAFT synthesis of PSKA, we looked for RAFT agents (CTA 1–3, Scheme ) to test their efficiency and find out the optimal polymerization conditions . The proper selection of the RAFT agent for SKA is crucial to target well‐defined polymers.…”

“…Since only a few publications are currently available referring to the RAFT synthesis of PSKA, we looked for RAFT agents (CTA 1-3, Scheme 2) to test their efficiency and find out the optimal polymerization conditions. [10,14,[16][17][18]20] The proper selection of the RAFT agent for SKA is crucial to target well defined polymers. Three trithiocarbonates (Scheme 2) were chosen as RAFT agents as they are more suitable for the solketal acrylate that belongs to "more active monomers" (MAMs).…”

“…For instance, highly stable aqueous magnetic fluids were prepared by coating Fe 3 O 4 nanoparticles with poly(glycerol monoacrylate) and its block copolymers. This procedure provided a good choice for preparing stable magnetic fluids with tailored surfaces and/or tailored functional groups on the surfaces of the magnetic nanoparticles . In copolymers of poly((ethylene glycol) methyl ether methacrylate) (PEGMA) and solketal acrylate (SKA), the dioxolane functional groups were deprotected to form 1,2‐diol groups and subsequently oxidized with HIO 4 to form reactive aldehyde groups.…”

Double hydrophilic block copolymers PEO‐b‐PGA: Synthesis, application as potential drug carrier and drug release via pH‐sensitive linkage

“…When THF was used as the solvent, the (co)polymerizations were quite slow and the polydispersity indexes of the homopolymers were high (1.32-1.52). Yan and coworkers 36 used cyclohexanone as polymerization solvent for ATRP of SA. The results they obtained were not so good probably because of the side reaction of cyclohexanone with ligand PMDETA.…”