Controlled/living radical polymerization: Features, developments, and perspectives

http://wwwcourses.sens.buffalo.edu/ce435/Riess03.pdf

Micellization of block copolymers

Keywords: Fragmentation Chain-Transfer ; Self-Assembled Monolayers ; Walled Carbon Nanotubes ; Well-Defined Polymer ; Nitroxide-Mediated Polymerization ; Block-Copolymer Brushes ; Poly(Methyl Methacrylate) Brushes ; Transfer Raft Polymerization ; Quartz-Crystal Microbalance ; Poly(Acrylic Acid) Brushes Reference EPFL-REVIEW-148464doi:10.1021/cr900045aView record in Web of Science Record created on 2010-04-23, modified on 2017-05-10

Polymer Brushes via Surface-Initiated Controlled Radical Polymerization: Synthesis, Characterization, Properties, and Applications

Polymer brushes: surface-immobilized macromolecules

Since its inception just over a half century ago, the field of biomaterials has seen a consistent growth with a steady introduction of new ideas and productive branches. This review describes where we have been, the state of the art today, and where we might be in 10 or 20 years. Herein, we highlight some of the latest advancements in biomaterials that aim to control biological responses and ultimately heal. This new generation of biomaterials includes surface modification of materials to overcome nonspecific protein adsorption in vivo, precision immobilization of signaling groups on surfaces, development of synthetic materials with controlled properties for drug and cell carriers, biologically inspired materials that mimic natural processes, and design of sophisticated three-dimensional (3-D) architectures to produce well-defined patterns for diagnostics, e.g., biological microelectromechanical systems (bioMEMs), and tissue engineering.

BIOMATERIALS: Where We Have Been and Where We Are Going

Role of initiator‐transfer agent‐terminator (iniferter) in radical polymerizations: Polymer design by organic disulfides as iniferters

A model for living radical polymerization

Some examples for living radical polymerization in homogeneous solution by four organic sulfides as photoiniferters have been proposed. In the photopolymerization of styrene (St) with diphenyl disulfide (DPD), tetraethyl thiuram disulfide (TD), benzyl diethyldithiocarbamate (BDC) and 2-phenylethyl diethyldithiocarbamate (PEDC), both the yields and the average-molecular weights of the polymers were found to increase as a function of the reaction time. The results obtained suggested that these polymerizations proceeded via a living radical mechanism. When these photoiniferters except DPD were used, the propagating polymer chain end was confirmed to be always the diethyldithiocarbamate [(C2 H5)2NCSS] group, which can further photodissociate into a reactive propagating radical and a less reactive small radical[(C2H5)2NCSS·] in order to result in successive insertion of monomer molecules into the dissociated bond.

Living Radical Polymerizations in Homogeneous Solution by Using Organic Sulfides as Photoiniferters

To synthesize efficiently block copolymers, the radical polymerization of vinyl monomers with the polymers obtained by tetraethyl thiuram disulfide(TD) as polymeric photoiniferters has been investigated. These photopolymerizations were found to proceed via a living radical mechanism, i.e. both the whole polymer yields and the average molecular weight of the block copolymers increased with increasing of the polymerization time. By applying these living radical polymerizations, various block copolymers consisting of two, three and four component blocks were obtained in good yields, suggesting that these techniques are effective and useful for synthesizing multi component block copolymers through radical polymerizations of polar vinyl monomers.

Efficient synthesis of two or multi component block copolymers through living radical polymerization with polymeric photoiniferters

In contrast to diethyl fumarate (DEF), diethyl maleate (DEM) did not homopolymerize with 2,2′-azobisisobutyronitrile (AIBN), but was found to undergo radical polymerization in the presence of amines such as morpholine (Mor). From the results of radical polymerization of DEF with AIBN and isomerization of DEM with Mor, the radical polymerization of DEM in the presence of both AIBN and Mor is considered to proceed via a new monomer-isomerization radical polymerization mechanism, i.e., DEM is isomerized first to DEF which is then homopolymerized. The most efficient isomerization catalyst was Mor among the amines examined. The apparent activation energies for the monomer-isomerization radical polymerization of DEM was calculated to be 91.9 kJ mol−1 and that for this isomerization was also obtained as 24.7 kJ mol−1. Moreover, Mor also acted as a retarder of radical polymerization of DEF. The composition relation of the copolymer to the feed monomer mixture in the copolymerizations of DEM with styrene, isobutyl vinyl ether, and acrylonitrile in the presence of Mor was found to be similar to that of the respective copolymerizations of DEF.

/pdf/polymers-from-1-2-disubstituted-ethylenic-monomers-vi-5ddq0z06qj.pdf

Masatoshi Yoshida

Papers

Role of initiator‐transfer agent‐terminator (iniferter) in radical polymerizations: Polymer design by organic disulfides as iniferters

A model for living radical polymerization

Living Radical Polymerizations in Homogeneous Solution by Using Organic Sulfides as Photoiniferters

Efficient synthesis of two or multi component block copolymers through living radical polymerization with polymeric photoiniferters

Polymers from 1,2-Disubstituted Ethylenic Monomers VI. Monomer-isomerization Radical Polymerization of Diethyl Maleate