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A new synthetic approach to thiol functional, well-defined amphiphilic block copolymers, which can be used to prepare multifunctional polymers and polymeric nanoparticles, is presented. Starting with a hydrophilic macroRAFT transfer agent and hydrophobic (meth)acrylate monomers that possess protected thiol groups, amphiphilic block copolymers are prepared in high yield. It is proven that the protected...
Anionic polymerization of EEGE with alkali metal based initiators has been shown to yield polyglycidol with low polydispersity indices for molecular weights up to M n ≈30,000. Higher molecular weights have not been obtained due to the occurrence of a chain transfer reaction to the monomer. Chain transfer to the monomer leads to P(EEGE) with an alcohol end group and an allylic alcoholate, which...
The synthesis of alternating poly(amide urethane)s 5a–d was performed in three steps using ε-caprolactone, diamines, and diphenyl carbonate as starting materials. The microstructure and nature of the end groups of the poly(amide urethane)s were determined by means of 1 H NMR spectroscopy, which reveals an alternating sequence of amide and urethane linkages in a linear chain with hydroxy and...
Several poly(urea urethane) oligomers 14a–e were prepared by polycondensation of N-(hydroxyalkyl)-2-oxo-1,3-diazepane-1-carboxamides 11a–e in bulk. The latter compounds were obtained under mild reaction conditions from a novel type of activated urethane/intramolecular blocked isocyanate 8 and a homologous series of amino alcohols. The influence of several catalysts (DABCO, Sn(octoate) 2 ,...
Alternating poly(amide urethane)s from ε-caprolactam, amino alcohols H 2 N-(CH 2 ) x -OH (x=2-6), and diphenyl carbonate were prepared by polycondensation of α-hydroxy-ω-O-phenylurethanes 4a-e. The degree of oligomerization was adjusted by the conversion. Oligomers with two or three O-phenylurethane end groups and predetermined molecular weight were prepared by polycondensation...
Monofunctional poly(ethylene oxide) macroinitiators with a molecular weight of 2000, 5000, 10 000, 20 000 and bifunctional poly(ethylene oxide) macroinitiators with a molecular weight of 20 000 were used for the atom transfer radical polymerisation (ATRP) of hydroxyethyl methacrylate (HEMA) in ethylene glycol as a solvent. The polymerisation proceeds in a controlled way up to high conversions. The...
Monofunctional PEO-macroinitiators (mPEO-F) were prepared from monohydroxyfunctional poly(ethylene oxide)s and 2-chloro-2-phenylacetylchloride. In order to synthesise poly(ethylene oxide)-block-poly(styrene) (PEO-b-PS) the macroinitiators were applied to the atom transfer radical polymerisation (ATRP) of styrene in the bulk. Well-defined block copolymers were obtained with predetermined molecular...
The copolymerization of 5-[(4-fluorophenyl)sulfonyl]-2-fluorobenzoic acid with bis(4-hydroxyphenyl)sulfone in 1,1-dioxothiolane with sodium carbonate as a base results in carboxylated poly(ether sulfone)s. The polycondensation polymerization, however, is associated with partial decarboxylation. Conversely, the copolymerization of 2,5-dihydroxybenzoic acid (hydroquinone carboxylic acid) with bis(4-fluorophenyl)sulfone...
The atom transfer radical polymerization (ATRP) of styrene and methyl methacrylate with differently substituted model and macroinitiators was performed, in order to evaluate qualitatively the structural features which affect the efficiency of the initiation step. It was found that substituents which stabilize radicals enhance the dissociation of the halogen atom and lead to high initiation efficiencies...
Copolymerization of equimolar amounts of 2,2-dimethyltrimethylene carbonate (DTC) with tetramethylene urea (TeU) results in a copolymer the microstructure of which depends on the reaction conditions and on the catalyst used. With sec-butyllithium, dibutylmagnesium and diethylzinc as a catalyst a nearly alternating copolymer, i.e. a polyurethane, was obtained. With dibutyldimethoxytin, tris(sec-butoxyaluminium),...
The dissolution of alkali metal salts, e.g. LiClO 4 , LiCF 3 SO 3 , NaSCN, NaI, NaCF 3 SO 3 and KSCN in poly(2,2-dimethyltrimethylene carbonate)-block-poly(ethylene oxide)-block-poly(2,2-dimethyltrimethylene carbonate) (PDTC-b-PEO-b-PDTC) results in solid polymeric electrolytes. Depending on the nature of the salt, differential scanning calorimetry (d.s.c.)...
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