Well‐defined polyolefin/poly(ε‐caprolactone) diblock copolymers: New synthetic strategy and application

Abstract

A new synthetic strategy, the combination of living polymerization of ylides and ring-opening polymerization (ROP), was successfully used to obtain well-defined polymethylene-b-poly(e-caprolactone) (PM-b-PCL) diblock copolymers. Two hydroxyl-terminated polymethylenes (PM-OH, M n ¼ 1800 g mol À1 (PDI ¼ 1.18) and M n ¼ 6400 g mol À1 (PDI ¼ 1.14)) were prepared using living polymerization of dimethylsulfoxonium methylides. Then, such polymers were successfully transformed to PM-b-PCL diblock copolymers by using stannous octoate as a catalyst for ROP of e-caprolactone. The GPC traces and 1 H NMR of PM-b-PCL diblock copolymers indicated the successful extension of PCL segment (M n of PM-b-PCL ¼ 5200-10,300 g mol À1 ; PDI ¼ 1.06-1.13). The thermal properties of the double crystalline diblock copolymers were investigated by differential scanning calorimetry (DSC). The results indicated that the incorporation of crystalline segments of PCL chain effectively influence the crystalline process of PM segments. The low-density polyethylene (LDPE)/PCL and LDPE/polycarbonate (PC) blends were prepared using PM-b-PCL as compatibilizer, respectively. The scanning electron microscopy (SEM) observation on the cryofractured surface of such blend polymers indicates that the PM-b-PCL diblock copolymers are effective compatibilizers for LDPE/PCL and LDPE/PC blends. Porous films were fabricated via the breath-figure method using different concentration of PM-b-PCL diblock copolymers in CH 2 Cl 2 under a static humid condition. V C 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 49: 511-517, 2011

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

“…A hydroxyl‐terminated PM has served as macroinitiator for the ring‐opening polymerization of cyclic ester monomers such as ε ‐caprolactone and lactide leading to the corresponding PM‐based copolymers. PM‐ b ‐PCL (PCL: polycaprolactone) has been successfully synthesized by sequential polymerization and ring‐opening polymerization (Scheme ) . The ring‐opening polymerization of ε ‐caprolactone required high temperature (80 °C), which helped the dissolution of the PM initiator, resulting in a homogeneous solution.…”

“…Scanning electron microscope (SEM) images of polymer blends: a) binary blends with LDPE/PCL = 70/30 (weight ratio); b) and c) ternary blends with LDPE/PCL/(PM‐ b ‐PCL) = 70/30/5 and 70/30/10 (weight ratio), respectively. Reproduced with permission . Copyright 2011, Wiley.…”

Well-defined polymethylene-based block co/terpolymers by combining anthracene/maleimide diels–alder reaction with polyhomologation

“…[16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32] This method is a general one opening new horizons for the synthesis of well-defined PE-based polymeric materials with different macromolecular architectures.…”

Novel polyethylene‐b‐polyurethane‐b‐polyethylene triblock copolymers: Facile synthesis and application

“…Block or graft copolymers containing PE segments are widely considered as high‐performance compatibilizers for the blends of polyethylene with other materials. Various types of polyethylene‐based block or graft copolymers have been synthesized and proven to be very impactful compatibilizers, such as polyethylene‐ b ‐poly(ε‐caprolactone) (PE‐ b ‐PCL), poly(methyl methacrylate)‐ b ‐polyethylene‐ b ‐poly(methyl methacrylate) (PMMA‐ b ‐PE‐ b ‐PMMA), polyethylene‐ b ‐poly(ethylene glycol) (PE‐ b ‐PEG), polyethylene‐ b ‐poly(lactic acid) (PE‐ b ‐PLA), polyethylene‐ b ‐poly(dimethylsiloxane) (PE‐ b ‐PDMS), polymethylene‐ b ‐polystyrene (PM‐ b ‐PS), polyethylene‐ g ‐poly(methyl methacrylate) (PE‐ g ‐PMMA), and polyethylene‐ g ‐polystyrene (PE‐ g ‐PS) …”