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The synthesis and characterization of poly(glycidol-co-glycidyl amine), poly(glycidol)-block-poly(glycidyl amine), and poly(glycidol) end-capped with a glycidyl amine unit is reported. Copolymerization of ethoxyethyl glycidyl ether with epichlorohydrin using tetraoctylammonium bromide/triisobutylaluminium as catalyst leads to statistical or block copolymers. Sequential addition of the monomers to the initiator leads to block copolymers while simultaneous copolymerization of the monomers results in statistical copolymers. The resulting polyethers with protected hydroxymethyl and chloromethyl side groups were converted in three steps to poly(epoxide)s with hydroxymethyl and aminomethyl side chains. These polymers have a high potential for the preparation of multifunctional polymers since amine and alcohol groups can be addressed selectively by electrophiles. An intermediate in the synthesis of these functional poly(epoxide)s are polyethers with hydroxymethyl and azidomethyl side chains. The azide group of these copolymers was further functionalized via a click reaction with propargyl alcohol proving the reactivity of the polymer bound azide group. Furthermore, preparation of poly(glycidol)s bearing a glycidyl amine end group is reported. [ABSTRACT FROM AUTHOR]

Copolyesters of pentadecalactone (PDL) with γ-methacryloyl--caprolactone (McrCL) and γ-benzoyl--caprolactone (BenzCL) were successfully prepared by means of enzymatic copolymerization using Novozyme 435 as catalyst and were characterized by means of NMR, SEC and DSC analyses. With γ-acetyl--caprolactone (AcetCL) and γ-acryloyl--caprolactone (AcrCL) as comonomers for PDL enzymatic copolymerization failed. Under polymerization conditions AcetCL and AcrCL rearrange into the thermodynamically more stable butyrolactones. An enantiomeric excess of BenzCL, not of McrCL, was found in the corresponding copolymer (poly(PDL-co-BenzCL)). DSC results prove clearly that by introducing functional caprolactone units along the PPDL backbone, the crystallinity of PPDL decreases. PDL based copolymers with double bonds, epoxide and amide groups in the main chain were obtained viaenzymatic copolymerization of PDL with Ambrettolide (Am), the corresponding epoxide (AmE) and 1-oxa-8-aza-cyclotetradecan-9,14-dione a 14-membered cyclic ester amide (cEA). The presence of these functional groups in the PPDL backbone allows tuning of the composition and consequently the properties of PPDL by lowering its crystallinity. [ABSTRACT FROM AUTHOR]

Linear and star-shaped polyglycidols were prepared using ethoxy ethyl glycidyl ether (EEGE) as monomer and 3-phenyl-1-propanol and dipentaerythritol as initiator, respectively. These polymers were treated with 2-chloroethylsulfonyl chloride to form reactive vinyl sulfonate end groups. The high reactivity of the vinyl sulfonate end groups toward amines, alcohols, and amino acids was investigated. All polymers were characterized by nuclear magnetic resonance and size exclusion chromatography. [ABSTRACT FROM AUTHOR]

When a linear or a four arm star-shaped polyglycidol is used as macroinitiator, densely grafted poly(glycidol- graft-ϵ-caprolactone) and poly(glycidol- graft- l-lactide) and loosely grafted poly[(glycidol- graft-ϵ-caprolactone)- co-glycidol] copolymers have been synthesized by chemical or, in the latter case, by enzymatic catalyzed ring-opening polymerization of ϵ-caprolactone and l-lactide. The well-defined copolymers possess similar molecular weights, but differ in their architecture, microstructure and chemical composition. The hydrolytic degradation behavior was studied in a phosphate buffer solution at pH 7.4 and 37 °C for up to 90 days. After different time periods, the mass loss was determined and the degraded copolymers were analyzed by means of NMR, size exclusion chromatography, and scanning electron microscopy. Compared to linear poly(ϵ-caprolactone), poly[(glycidol- graft-ϵ-caprolactone)- co-glycidol] shows a change of the degradation mechanism and a tremendous enhancement of polymer degradation. As this effect is attributed to the high concentration of hydroxy groups at the polyglycidol backbone, this work points out a new possibility to tailor the degradation profiles of polyesters by the introduction of functionality into the polymeric material. [ABSTRACT FROM AUTHOR]

Heterografted molecular bottle brushes, i.e., poly(glycidol-graft--caprolactone-acetyl)-co-(glycidol-graft-methyl methacrylate) P(G-graft-CLAC)-co-(G-graft-MMA) and poly(glycidol-graft--caprolactone-acetyl)-co-(glycidol-graft-n-butyl methacrylate) P(G-graft-CLAC)-co-(G-graft-BMA) were prepared in two steps starting with a linear polyglycidol. In the first step an approximately 50% homografted polymer poly(glycidol-graft--caprolactone-acetyl)-co-glycidol P(G-graft-CLAC)-co-G was obtained via ring-opening polymerization of -caprolactone using polyglycidol as a multifunctional macroinitiator and Novozyme 435 (Lipase B from Candida antarctica(CALB) immobilized on a macroporous resin) as a catalyst. Selective acetylation of the hydroxy groups at the graft ends was achieved via enzymatic acetylation with vinyl acetate, and the hydroxy groups at the backbone were acylated with 2-bromo-2-methylpropionyl bromide. Finally poly(methyl methacrylate) or poly(n-butyl methacrylate) grafts were attached by atom transfer radical polymerization. The heterografted molecular bottle brushes show monomodal elution curves in gel permeation chromatographic analyses. Differential scanning calorimetry confirms the existence of phase separated domains for both polymers. [ABSTRACT FROM AUTHOR]

Primary amine groups of branched poly(ethylene imine) (PEI) were functionalized with quaternary ammonium groups, alkyl chains of different length, allylic and benzylic groups in a one-step reaction, using a carbonate coupler. The structure of the obtained amphiphilic polymers was determined by means of 1H and 13C NMR spectroscopy. Depending on their hydrophilic/hydrophobic balance, the obtained polymers can be used as water-soluble disinfectants and for antimicrobial coating materials. The bactericidal properties of some of the amphiphilic polymers against Gram-negative and Gram-positive bacteria were investigated. Minimal inhibitory concentrations (log 4 reduction of bacterial growth) against Escherichia coliand Bacillus subtiliswere determined in the range of 0.3−0.4 mg/mL and 0.03−0.04 mg/mL for water-soluble polymers. Glass slides coated with functionalized PEIs showed a reduction of colony forming units of at least 95%, at best 99.9%, against E. coliand B. subtilis. [ABSTRACT FROM AUTHOR]

Anionic ring-opening polymerization and copolymerization of allyl glycidyl ether (AGE), tert-butyl glycidyl ether (tBuGE), and ethoxyethyl glycidyl ether (EEGE) was performed using potassium 3-phenyl-1-propanol as initiator. The polymers poly(AGE), poly(tBuGE), poly(EEGE) as well as poly(AGE-co-tBuGE), poly(AGE-co-EEGE), and poly(EEGE-co-tBuGE) were obtained with controlled degree of polymerization, narrow molecular weight distribution and a predetermined ratio of repeating units. First-order kinetics with respect to the glycidyl monomers were found for homo- and copolymerization. The removal of protection groups from the homopolymers was achieved using trifluoroacetic acid for poly(tBuGE), aqueous hydrochloric acid for poly(EEGE), and a palladium catalyst for poly(AGE); in all cases a linear poly(glycidyl ether) (poly(GE), 1) was obtained. The following conversions were achieved by selective removal of only one protection group:  using aqueous hydrochloric acid, poly(AGE-co-EEGE) was converted to poly(AGE-co-GE) 4; using trifluoroacetic acid, poly(AGE-co-tBuGE) was converted to poly(AGE-co-glycidyl trifluoroacetate), 5; and by using Pd/C and p-toluenesulfonic acid poly(AGE-co-tBuGE) was converted to poly(GE-co-tBuGE), 3. A selective removal of only one protection group from poly(EEGE-co-tBuGE) was not possible. Treatment with aqueous hydrochloric acid or with trifluoroacetic acid lead to poly(GE), 1, and poly(glycidyl trifluoroacetate), 2, respectively. Finally free hydroxymethyl groups of the polymers poly(GE-co-tBuGE), 3, and poly(AGE-co-GE), 4, were partially converted in a polymer analogous reaction using propargyl bromide to the corresponding polymers with glycidyl propargyl ether (GPE) repeating units. In a model reaction one of these polymers with GPE repeating units was successfully converted with an azido sugar moiety in a (2 3) cycloaddition reaction. [ABSTRACT FROM AUTHOR]

First‐generation dendritic macromonomers with a methacryloyl end group on one side, long alkyl chains on the other side, and a biuret system with two urethane groups in the core have been synthesized. The synthesis comprises three steps with hexamethylene diisocyanate uretdione as the starting material. The branching points were introduced via biuret groups and the prepared macromonomers were polymerized by free and controlled radical polymerization. Depending on the reaction conditions linear dendronized polymers as well as branched dendronized polymers and microgels with long alkyl chains were obtained. Scanning force microscopy was used to visualize high molecular weight molecules spincoated on highly oriented pyrolytic graphite. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 614–628, 2007 [ABSTRACT FROM AUTHOR]