A new multifunctional initiator system for the living cationic polymerization of vinyl ethers

Abstract

Combination of hexa(chloromethyl)melamine (HCMM) and zinc chloride was found to be a multifunctional initiator system for the living cationic polymerization of isobutyl vinyl ether. HCMM was synthesized by reaction of hexa(methoxymethyl)melamine and boron trichloride. Characterization of the polymers by means of GPC and 1H NMR showed that initiation was rapid and quantitative and that the initiator is hexafunctional, leading to six‐armed star‐shaped polymers.

Benzylic triflates prepared in-situ: novel initiators for mono-, bi- and trifunctional living poly(THF)s

“…Thus, new initiators of three and more functionalities can provide an additional and attractive means to produce novel telechelics having star-shaped architectures. In this connection, a variety of multifunctional initiator systems has been recently proposed for anionic, [4] cationic, [5][6][7][8] radical, [9][10][11][12][13] as well as ring-opening processes. [14][15][16] In case of the cationic ring-opening polymerization of THF, mono-and bifunctional living poly(THF)s can be readily prepared by methyl triflate and by triflic anhydride as an initiator, respectively.…”

Well-Defined Star-Shaped Aromatic Polyamides from Chain-Growth Polymerization of Phenyl 4-(Alkylamino)benzoate with Multifunctional Initiators

“…Among a variety of synthetic approaches to star polymers, living polymerization is the most appropriate for the synthesis of well-defined star polymers, which can be divided into three methods: (1) living polymerization with a multifunctional initiator, (2) coupling reaction of linear living polymers with a multifunctional coupling agent, and (3) linking reaction of linear living polymers with a divinyl compound. Method 1 can yield star polymers with a determined number of arms and has been successfully employed in various living polymerizations, including anionic, cationic, radical polymerization, and ring-opening processes . However, polycondensation is not applicable to this method for the synthesis of well-defined star-shaped polymers because polycondensation does not proceed in a chain polymerization manner.…”

Star-Shaped Poly(tetrahydrofuran) with Reactive End Groups: Design, MALDI-TOF Study, and Solution Behavior

“…For ionic polymerizations, these are often difficult to prepare due to the poor solubility and stability of the multiply charged complexes. [8][9][10][11] Recent developments in atom-transfer radical polymerization (ATRP) and reversible additionfragmentation chain-transfer polymerization (RAFT) have made it possible to use radical polymerization for the controlled synthesis of star polymers. With these techniques, a variety of multifunctional initiators have been developed and successfully used.…”

“…The central core can be built upon reaction of short living chains with a bifunctional monomer, but stars with a large fluctuation of their functionalities are obtained. , For other core first approaches, the synthesis of a well-defined multifunctional initiator is required. For ionic polymerizations, these are often difficult to prepare due to the poor solubility and stability of the multiply charged complexes. − Recent developments in atom-transfer radical polymerization (ATRP) and reversible addition−fragmentation chain-transfer polymerization (RAFT) have made it possible to use radical polymerization for the controlled synthesis of star polymers. With these techniques, a variety of multifunctional initiators have been developed and successfully used. − …”