Bis-dendritic polyethylene prepared by ring-opening metathesis polymerization in the presence of bis-dendritic chain transfer agents

Telechelic polyethylene, poly(ethylene-co-vinyl acetate) and triblock copolymers based on ethylene and vinyl acetate by iodine transfer polymerization

Various iodo functionalized chain transfer agents (CTAs) were successfully employed in the iodine transfer polymerization (ITP) of ethylene conducted at 80 bars at 70°C in dimethylcarbonate. Comparative studies performed on...

Design and synthesis of a dual imageable theranostic platinum prodrug for efficient cancer therapy

Platinum-based chemotherapeutic agents are considered first-line treatments for various cancers but their application is limited by the lack of site specificity and severe side effects.

Advances in the synthesis of silyl-modified polymers (SMPs)

Silyl-modified polymers (SMPs) are being synthesized from chemical modification and olefin metathesis strategies.

Regioselective cross metathesis for block and heterotelechelic polymer synthesis

Cross metathesis of polymers made from 3-substituted cyclooctene derivatives produce regio- and stereoregular block and hetereotelechelic polymers.

α,ω-Bis(trialkoxysilyl) difunctionalized polycyclooctenes from ruthenium-catalyzed chain-transfer ring-opening metathesis polymerization

ROMP/CM of COE using bis(trialkoxysilyl)alkenes CTAs and Ru catalysts affords a series of bis(trialkoxysilyl) difunctionalized polyolefins.

Divinyl-end-functionalized polyethylenes: ready access to a range of telechelic polyethylenes through thiol-ene reactions

Telechelic α,ω-iodo-vinyl-polyethylenes (Vin-PE-I) were obtained by catalytic ethylene polymerization in the presence of [(C5 Me5 )2 NdCl2 Li(OEt2 )2 ] in combination with a functionalized chain-transfer agent, namely, di(10-undecenyl)magnesium, followed by treatment of the resulting di(vinylpolyethylenyl)magnesium compounds ((vinyl-PE)2 Mg) with I2 . The iodo-functionalized vinylpolyethylenes (Vin-PE-I) were transformed into unique divinyl-functionalized polyethylenes (Vin-PE-Vin) by simple treatment with tBuOK in toluene at 95 °C. Thiol-ene reactions were then successfully performed on Vin-PE-Vin with functionalized thiols in the presence of AIBN. A range of homobifunctional telechelic polyethylenes were obtained on which a hydroxy, diol, carboxylic acid, amine, ammonium chloride, trimethoxysilyl, chloro, or fluoroalkyl group was installed quantitatively at each chain end.

A dumbbell-like supramolecular triblock copolymer and its self-assembly of light-responsive vesicles

The work reports a dumbbell-like supramolecular triblock copolymer and its self-assembly of light-responsive monolayer vesicles.

Responsive linear-dendritic block copolymers

The combination of dendritic and linear polymeric structures in the same macromolecule opens up new possibilities for the design of block copolymers and for applications of functional polymers that have self-assembly properties. There are three main strategies for the synthesis of linear-dendritic block copolymers (LDBCs) and, in particular, the emergence of click chemistry has made the coupling of preformed blocks one of the most efficient ways of obtaining libraries of LDBCs. In these materials, the periphery of the dendron can be precisely functionalised to obtain functional LDBCs with self-assembly properties of interest in different technological areas. The incorporation of stimuli-responsive moieties gives rise to smart materials that are generally processed as self-assemblies of amphiphilic LDBCs with a morphology that can be controlled by an external stimulus. Particular emphasis is placed on light-responsive LDBCs. Furthermore, a brief review of the biomedical or materials science applications of LDBCs is presented.

Synthesis of telechelic olefin polymers via catalyzed chain growth on multinuclear alkylene zinc compounds

Multinuclear alkylene zinc (MAZ) compounds of the type EtZn-(R″-Zn)n-Et (R″ = ethyl and propyl branched alkylene groups) were synthesized by a simple one-step procedure in nonpolar hydrocarbon solvents from α,ω-dienes (e.g., 1,7-octadiene or 1,9-decadiene) and diethylzinc using a bis(salicylaldiminato)Zr(IV) complex, [(2-methylcyclohexyl)N═CH(2-O-C6H3-3,5-di-tert-butyl)]2ZrMe2, as a catalyst. The MAZ serves as a divalent reversible chain-transfer agent for olefin polymerization, resulting in telechelic Zn-metalated polyolefins whose molecular weights are controllable over a wide range. The Zn-terminated telechelics serve as a polymer precursor for further reactions and can be converted into a variety of telechelic functionalized polyolefins in high yield.

End-functionalized ROMP polymers for Biomedical Applications

We present two novel allyl-based terminating agents that can be used to end-functionalize living polymer chains obtained by ring-opening metathesis polymerization (ROMP) using Grubbs' third generation catalyst. Both terminating agents can be easily synthesized and yield ROMP polymers with stable, storable activated ester groups at the chain-end. These end-functionalized ROMP polymers are attractive building blocks for advanced polymeric materials, especially in the biomedical field. Dye-labeling and surface-coupling of antimicrobially active polymers using these end-groups were demonstrated.