Cationic Polymerization of Cyclic Ethers Initiated by Macromolecular Dioxolenium Perchlorate

Cyclic Oligomers in the Cationic Polymerization of Heterocycles

The cationic polymerization of heterocyclic monomers may lead to polymers containing substantial, yet Variable amounts of cyclic oligomers. This review gives a survey of the systems where such oligomers have been found. Oligomer formation is generally observed in the polymerization of oxiranes and thiiranes. The most frequently observed oligomers are the cyclic dimers and cyclic tetramers but o...

Polymerization of cyclic esters initiated by carnitine and tin (II) octoate.

Low-molecular weight poly(epsilon-caprolactone), polylactides and copolymers of epsilon-caprolactone and lactides were obtained by the polymerization of cyclic esters in the presence of a carnitine/SnOct(2) system. Their structures were proven by means of MALDI-TOF, IR and NMR studies. Effects of temperature, reaction time and carnitine dosage on the polymerization process were examined.

Well-controlled ring-opening polymerization of cyclic esters initiated by dialkylaluminum β-diketiminates.

A series of aluminum alkyl complexes nacnacRAlMe2 (2a-2h) bearing aliphatic N-substituted β-diketiminate ligands (nacnacRH = N,N'-dialkyl-2-amino-4-iminopent-2-enes), were prepared from the reaction of trialkyl aluminum and the corresponding β-diketimines. All these aluminum complexes were characterized by NMR, elemental analysis and HRMS spectroscopy. The molecular structures of complexes 2a, ...

Macromolecular engineering by atom transfer radical polymerization.

This Perspective presents recent advances in macromolecular engineering enabled by ATRP. They include the fundamental mechanistic and synthetic features of ATRP with emphasis on various catalytic/initiation systems that use parts-per-million concentrations of Cu catalysts and can be run in environmentally friendly media, e.g., water. The roles of the major components of ATRP--monomers, initiato...

Cationic polymerization of glycidyl ethers and furans: improved electron beam and UV cured epoxy networks