Synthesis of well‐defined amphiphilic polymethylene‐b‐poly(ε‐caprolactone)‐b‐poly(acrylic acid) triblock copolymer via a combination of polyhomologation, ring‐opening polymerization, and atom transfer radical polymerization

Abstract

Well-defined amphiphilic polymethylene-b-poly(ecaprolactone)-b-poly(acrylic acid) (PM-b-PCL-b-PAA) triblock copolymers were synthesized via a combination of polyhomologation, ring-opening polymerization (ROP), and atom transfer radical polymerization (ATRP). First, hydroxyl-terminated polymethylenes (PM-OH; M n ¼ 1100 g mol À1 ; M w /M n ¼ 1.09) were produced by polyhomologation followed by oxidation. Then, the PM-b-PCL (M n ¼ 10,000 g mol À1 ; M w /M n ¼ 1.27) diblock copolymers were synthesized via ROP of e-caprolactone using PM-OH as macroinitiator and stannous octanoate (Sn(Oct) 2 ) as a catalyst. Subsequently, the macroinitiator transformed from PM-b-PCL in high conversion initiated ATRPs of tert-butyl acrylate ( t BA) to construct PM-b-PCL-b-P t BA triblock copolymers (M n ¼ 11,000-14,000 g mol À1 ; M w /M n ¼ 1.24-1.26). Finally, the PM-b-PCL-b-PAA triblock copolymers were obtained via the hydrolysis of the P t BA segment in PM-b-PCL-b-P t BA triblock copolymers. The chain structures of all the polymers were characterized by gel permeation chromatography, proton nuclear magnetic resonance, and Fourier transform infrared spectroscopy. Porous films of such triblock copolymers were fabricated by static breath-figure method and observed by scanning electron microscope. The aggregates of PM-b-PCL-b-PAA triblock copolymer were studied by transmission electron microscope.

Breath Figure: A Nature-Inspired Preparation Method for Ordered Porous Films

“…The BFA films were endowed with unique optical properties because of the photoactive moieties.Multiblock copolymers were also employed to prepare BFA films. 253,254 Our group investigated the formation of polystyrene-b-polybutylene-b-polystyrene (SBS, 46) and polystyrene-b-polyisoprene-b-polystyrene (SIS,47) …”

Synthetic of pH-Sensitive PEG-b-PHEMA(His) Polymers andthe Study of Micelle

“…一锅法作为公认的高效组合式聚合反应方法, 为特 殊功能高分子的聚合提供了有效的手段 [1,2] . 点击化学 具有反应条件温和、产率可控、无副产物等优点, 已逐 步成为化学合成的重要方法, 其中具有代表性的铜作催 化剂的叠氮-炔环加成反应目前已被用在多嵌段聚合 物、树枝状分子等聚合物的合成上 [3] .…”

Polymethylene‐Based Copolymers by Polyhomologation or by Its Combination with Controlled/Living and Living Polymerizations

“…After the ring‐opening polymerization, the reaction of the –OH end group with 2‐bromoisobutyryl bromide produced a macroinitiator for further ATRP. A triblock copolymer PM‐ b ‐PCL‐ b ‐PAA has been synthesized by sequential polyhomologation, ring‐opening polymerization, and ATRP (Scheme ) . From a PM‐OH with a molecular weight of 1100 g mol −1 , ε ‐caprolactone was polymerized in the presence of Sn(Oct) 2 .…”