The special of Chemical Review informs about studies conducted on single-electron transfer and single-electron transfer degenerative chain transfer living radical polymerization. Researchers have demonstrated that living radical polymerization (LRP) can be significantly effective for the synthesis of tailored polymers. The special issue aims at covering the latest progress in two related polymerization methodologies that rely on single-electron transfer (SET), single-electron transfer degenerative chain transfer living radical polymerization (SET-DTLRP), and single-electron transfer living radical polymerization (SET-LRP). It is demonstrated that SET-DTLRP proceeds through SET initiation and competition of SET activation, deactivation, and degenerative transfer (DT). SET-LRP proceeds exclusively through a SET initiation, activation, and deactivation. It is also revealed that the two techniques have arose from investigations into Cu-catalyzed LRP initiated with sulfonyl halides.

Single-Electron Transfer and Single-Electron Transfer Degenerative Chain Transfer Living Radical Polymerization

numerous polyethylene or polypropylene compounds have been synthesized by metal-catalyzed coordination-insertion polymerization. On the other hand, organometallic catalysts * To whom correspondence should be addressed. E-mail: nozaki@chembio.t.utokyo.ac.jp. Akifumi Nakamura (left) was born in 1984 in Kanagawa, Japan. He received his B.S. degree in 2007 and M.S. degree in 2009 from the University of Tokyo under the guidance of Professor Kyoko Nozaki. During that time he joined Professor Keiji Morokuma’s group at Kyoto University as a visiting student. In 2009, he started his Ph.D. study at the University of Tokyo under the guidance of Professor Kyoko Nozaki. He is also a research fellow of the Japan Society for the Promotion of Science. His research interests include synthetic organic chemistry, organometallic chemistry, computational chemistry, and polymer chemistry.

Coordination−Insertion Copolymerization of Fundamental Polar Monomers

A radiation sensitive resin composition comprising (A) a fluorine-containing copolymer of hexafluoropropylene, at least one compound selected from the group consisting of unsaturated carboxylic acids and unsaturated carboxylic anhydrides, and an unsaturated compound (B) an acid generating compound which generates an acid upon exposure to radiation; (C) a cross-linkable compound; and (D) an organic solvent. The composition suitable is useful for a negative resist for forming a mask for the production of a circuit such as a semiconductor integrated circuit or a thin film transistor circuit for liquid crystal displays as well as a material for forming a permanent film such as an interlaminar insulating film or a color filter protective film.

Radiation-sensitive resin composition

The effects of weight-average molecular weight (MW) and short and long chain branching on the linear viscoelastic behavior of polyethylene (and ethylene−α-olefin copolymers) are described. Short chain branching had no effect up to a comonomer (butene) content of 21.2 wt %. The zero shear viscosity of the linear polyethylenes scaled in the expected manner with MW. Using a high molecular weight, narrow molecular weight distribution (MWD), linear polyethylene, an estimate of the plateau modulus and molecular weight between entanglements (Me) was obtained. A solution property based technique for quantifying levels of long chain branching well below 1 LCB/104C in polyethylene is presented. Also, the applicability of 13C NMR for measuring such LCB levels is demonstrated. For metallocene polyethylene, long chain branching (LCB) increased the zero shear viscosity as compared to that of a linear material of the same molecular weight. LCB also broadened the relaxation spectrum by adding a long time relaxation mode ...

Effect of Molecular Structure on the Linear Viscoelastic Behavior of Polyethylene

Transition metal catalysts for controlled radical polymerization

Methods for the addition polymerization of cycloolefins using a cationic Group 10 metal complex and a weakly coordinating anion of the formula: [(R')zM(L')x(L')y]b [WCA]d wherein [(R')zM(L')x(L')y] is a cation complex where M represents a Group 10 transition metal; R' represents an anionic hydrocarbyl containing ligand; L' represents a Group 15 neutral electron donor ligand; L' represents a labile neutral electron donor ligand; x is 1 or 2; and y is 0, 1, 2, or 3; and z is 0 or 1, wherein the sum of x, y, and z is 4; and [WCA] represents a weakly coordinating counteranion complex; and b and d are numbers representing the number of times the cation complex and weakly coordinating counteranion complex are taken to balance the electronic charge on the overall catalyst complex.

Catalyst and methods for polymerizing cycloolefins

A single component ionic catalyst consists essentially of an organonickel complex cation, and a weakly coordinating neutral counteranion. The cation is a neutral bidentate ligand removably attached to a Group VIII transition metal in an organometal complex. The ligand is easily displaced by a norbornene-type (NB-type) monomer in an insertion reaction which results in an unexpectedly facile addition polymerization. A NB-type monomer includes NB or substituted NB, or a multi-ringed cycloolefin having more than three rings in which one or more of the rings has a structure derived from NB, and a ring may have an alicyclic alkyl, alkylene or alkylidene substituent. The insertion reaction results in the formation of a unique propagating species more soluble in a polar than in a non-polar solvent and devoid of an available β-hydrogen for termination. The ensuing propagation of a polymer chain proceeds without measurable unsaturation. The chain continues to grow until the insertion of a monoolefinic chain transfer reagent results in substantially all chains being terminated with the residue of the chain transfer reagent. This unique chain transfer reaction allows one to control the molecular weight in a relatively narrow range. The reaction mixture for controlling the mol wt of the polymer chains may contain any other catalyst which generates a propagating species by an insertion reaction in an essentially anhydrous solvent. Both, mol wt and glass transition temperature Tg are tailored to provide a weight average mol wt Mw>20,000 but preferably not greater than about 500,000, and a T g in the range from about 150° C. to about 400° C. or higher, if desired.

Process for making polymers containing a norbornene repeating unit by addition polymerization using an organo (nickel or palladium) complex

Catalytic Copolymerization of Ethylene and Norbornene in Emulsion

Silyl substituted polymers of polycycloolefins are provided as well as catalyst systems for their preparation. The polymers of the invention include polycyclic repeat units that contain pendant silyl functional groups represented by the following formulae: ##STR1## wherein A is a divalent radical selected from the following structures: ##STR2## R 9 independently represents hydrogen, methyl, or ethyl; R 10 , R 11 , and R 12 independently represent halogen, linear or branched (C 1 to C 20 ) alkyl, linear or branched (C 1 to C 20 ) alkoxy, linear or branched (C 1 to C 20 ) alkyl carbonyloxy, (C 1 to C 20 ) alkyl peroxy, and substituted or unsubstituted (C 6 to C 20 ) aryloxy; R 10 , R 11 , and R 12 together with the silicon atom to which they are attached form the group: ##STR3## n is a number from 0 to 5; and n' is 0 or 1; and n" is a number from 0 to 10.

Addition polymers of polycycloolefins containing silyl functional groups

The invention discloses methods of preparing copolymers from norbornene-type monomers and cationically polymerizable monomers or polymers from catalytically polymerizable monomers by employing Group VIII transition metal ion source in a solvent for said monomers at a temperature in the range from -100 °C to 120 °C. Also disclosed are copolymers from norbornene-type monomers and catalytically polymerizable monomers.

Brian L. Goodall

Papers

Catalyst and methods for polymerizing cycloolefins

Process for making polymers containing a norbornene repeating unit by addition polymerization using an organo (nickel or palladium) complex

Catalytic Copolymerization of Ethylene and Norbornene in Emulsion

Addition polymers of polycycloolefins containing silyl functional groups

Homopolymers and copolymers of cationically polymerizable monomers and method of their preparation