Synthesis of amphiphilic heteroarm star‐shaped polymer via free radical polymerization using polyfunctional chain transfer agent and its self‐assembly behavior

Abstract

Amphiphilic heteroarm star-shaped polymers have important theoretical and practical significance. In this work, amphiphilic heteroarm star-shaped polymer was synthesized by the use of polyfunctional chain transfer agent via sequential free radical polymerization in two steps. First, conventional free radical polymerization of methyl methacrylate (MMA) initiated by 2,2 0 -azobis (isobutyronitrile) (AIBN) was carried out in the presence of polyfunctional chain transfer agent, pentaerythritol-tertrakis (3-mercaptopropinate) (PETMP). At appropriate monomer conversion, about two-arm s-PMMA having two residual thiol groups at the chain center was obtained. Second, the s-PMMA obtained above was used as macro-chain-transfer agent for free radical polymerization of acrylic acid (AA). The heteroarm star-shaped polymer with the hydrophobic PMMA segment and the hydrophilic PAA segment was obtained. The successful synthesis of heteroarm star-shaped polymers, (PMMA) 2 (AA) 2 , was confirmed by 1 H-NMR and its self-assembly behavior in different solvents.

Synthesis of cholic acid-core poly(ε-caprolactone-ran-lactide)-b-poly(ethylene glycol) 1000 random copolymer as a chemotherapeutic nanocarrier for liver cancer treatment

“…30 Branched polymers with useful rheological and mechanical properties, such as star-shaped polymers, hyperbranched polymers and dendrimers, have attracted a great deal of attention by research groups all over the world. [31][32][33] With several branches extending from a single point, 34 star-shaped polymers applied in drug carriers have advantages such as a lower solution viscosity, a smaller hydrodynamic radius, a higher encapsulation efficiency and loading content compared with linear polymers in a drug delivery system. 32,[35][36][37] Therefore, star-shaped block copolymers based on PCL, PLA, PEG 1k and CA could potentially be used to prepare excellent biodegradable drug-carriers.…”

“…[31][32][33] With several branches extending from a single point, 34 star-shaped polymers applied in drug carriers have advantages such as a lower solution viscosity, a smaller hydrodynamic radius, a higher encapsulation efficiency and loading content compared with linear polymers in a drug delivery system. 32,[35][36][37] Therefore, star-shaped block copolymers based on PCL, PLA, PEG 1k and CA could potentially be used to prepare excellent biodegradable drug-carriers. 38,39 In this study, we successfully synthesized a star-shaped random copolymer CA-(PCL-ran-PLA)-b-PEG 1k with three branch arms for docetaxel (DTX) delivery.…”