Synthesis and characterization of biodegradable A–B–A triblock copolymers containing poly(ϵ‐caprolactone) A blocks and poly(trans‐4‐hydroxy‐L‐proline) B blocks

Abstract

were synthesized by ring-opening polymerization from dihydroxyl-terminated macroinitiator poly(trans-4-hydroxy-N-benzyloxycarbonyl-L-proline) (PHpr) and e-caprolactone (e-CL) with stannous octoate as the catalyst. The molecular weights were characterized with gel permeation chromatography and matrix-assisted laser desorption/ionization timeof-flight mass spectrometry. With an increase in the contents of e-CL incorporated into the copolymers, a decrease in the glass-transition temperature (T g ) was observed. The T g values of copoly(4-phenyl-e-caprolactone) and copoly(4-methyl-e-caprolactone) were higher than T g of copoly(e-caprolactone). Their micellar characteristics in an aqueous phase were investigated with fluorescence spectroscopy, dynamic light scattering, and transmission electron microscopy. The block copolymers formed micelles in the aqueous phase with critical micelle concentrations in the range of 1.00-1.36 mg L À1 . With higher molecular weights and hydrophobic components in the copolymers, a higher critical micelle concentration was observed. As the feed weight ratio of antitriptyline hydrochloride (AM) to the polymer increased, the drug loading increased. The micelles exhibited a spherical shape, and the average size was less than 250 nm. The in vitro hydrolytic degradation and controlled drug release properties of the triblock copolymers were also investigated. V V C 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: [4268][4269][4270][4271][4272][4273][4274][4275][4276][4277][4278][4279][4280] 2006

Mass Spectrometry of Synthetic Polymers

“…The characterization of possible shape-memory polymers containing short aramid hard segments and poly(3-caprolactone) soft segments was partially performed by MALDI-TOF MS . This MS technique was also used for monitoring the synthesis of poly[poly(ethylene glycol)- co -cyclic acetal]-based hydrogels , melt copolymers including polyesters , as well as in the microwave-assisted formation of poly(ether−ester)s of aliphatic isosorbide diols , in the synthesis of biodegradable A−B−A triblock copolymers containing poly(ε-caprolactone) A blocks and poly( trans -4-hydroxy- l -proline) B blocks , for structure analysis of amphiphilic poly(ethylene oxide)- graft -polystyrene and poly(ethylene oxide)- graft -poly(methyl acrylate) copolymer brushes , , for poly(styrene−vinylpyrrolidone) and poly(methyl methacrylate−vinylpyrrolidone) diblock copolymers , and for the characterization of poly(fluorooxetane- co -THF) . Furthermore, this technique was employed for the analysis of electrosynthezised poly[1-(thiophene-2-yl)benzothieno[3,2- b ]benzothlophene], which represents a novel fluorescent and conducting polymer .…”

Synthesis of amphiphilic pseudopolyamino acid‐containing ABC‐triblock copolymers and micellar characterizations

“…An earlier work of this study 14 reports the synthesis and micellar characterization amphiphilic ABA triblock copolymers based on hydrophilic dihydroxyl-terminated pseudo poly(trans-4-hydroxy-Nbenzyloxycarbonyl-L-proline) (PNZHpr) macroinitiators (B block) and hydrophobic PCL (A block). This article describes the synthesis of amphiphilic ABC triblock copolymers comprising methoxy poly(ethylene glycol) (MPEG) for its hydrophilicity, nontoxicity, biocompatibility and nonimmunogenitity (A block), pseudo poly (trans-4-hydroxy-L-proline) (PHpr) in which hydroxyproline is a natural and major constituent of collagen (B block), and hydrophobic PCL for its biocompatible, biodegradable, and high permeability to drugs (C block).…”

Proline‐based polymeric monoliths: Synthesis, characterization, and applications as organocatalysts in aldol reaction

“…Proline has also been modified to different proline‐based polymers for studies and applications other than polymer catalysts. These polymers include poly(proline),49 acryloyl‐ L ‐proline esters,50–57 poly(acryloyl‐ L ‐proline methyl ester/styrene),58 proline‐substituted acrylamide (AAm),59 and copolymers as poly(ester‐carbonate)60 or block copolymers and derived from proline derivatives 61–63…”