ionic polymerization

ionic polymerization

[ī′än·ik pə‚lim·ə·rə′zā·shən]
(organic chemistry)
Polymerization that proceeds via ionic intermediates (carbonium ions or carbanions) than through neutral species (olefins or acetylenes).
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
The eleven selections that make up the main body of the text are grouped in parts devoted to the basic structure and properties of silicones, silicone emulsions and microemulsions, ionic polymerization of silicones in aqueous media, silicone water-based elastomers, and a wide variety of other related subjects.
The behavior of molecular structure in PE coatings depends greatly on which polymerization mechanism predominates in the coatings formation, i.e., the free-radical polymerization or the ionic polymerization occurs in the polymerization reaction.
Controlled radical polymerization (CRP) combines the advantages of free-radical polymerization with those of living ionic polymerization: versatility in monomer type and process conditions, and control over polymer-chain microstructure.
Characterization, and Photoinitiated Cat ionic Polymerization of Silicon-Contain-Lug Epoxy Resins." J.
Elias, founding member of the Michigan Molecular Institute, bridges the gap between introductory texts and a collections of monographs to create a fundamental volume on the chemical structure and principles of synthesis of macromolecules, their constitution, characterization, configuration, conformation, general aspects of polymerization, the thermodynamics of polymerization, ionic polymerization, coordination polymerization, free-radical polymerization, polymerization by radiation or in ordered states, copolymerization, polycondensation and polyaddition, biological polymerization, reactions to macromolecules, and molecular engineering.
They also cover the application of polyhydroxyalkanoates from soybean oil and other vegetable oils; the synthesis and properties of soy-based biopolymeric composites; the preparation, properties, and applications of soy protein isolate bioplastics, soy protein isolate-based films, and soy protein-based blends; the use of inorganic nanofillers as reinforcement in the soy protein matrix; different methods used for the synthesis of soy polyol-based polyurethanes and their bioplastic applications; and the free radical and ionic polymerization of regular and conjugated soybean oil for sustainable bioplastics and biocomposites.
The previous section devoted to reaction kinetics has outlined how the intermediates species formed in the sol-gel process may interact with the course of vinyl ether ionic polymerization. However, an appropriate choice of film thickness (e [greater than or equal to] 2 [micro] m) was found to minimize the con-comitancy of both reactions in a way to induce first the "sensitive" cationic process and subsequently the sol-gel one.
International Union of Pure & Applied Chemistry, International Symposium on Ionic Polymerization, Goodyear Polymer Science Center, Akron, OH, Rubber Division (330) 972-7814; www.rubber.org--July 10-15.
26-31, International IUPAC Symposium on Ionic Polymerization
It is possible to distinguish the following principal situations in a polymerization process: polycondensation, ionic polymerization, and free-radical polymerization.
Unlike ionic polymerizations, termination still plays a significant role in these polymerizations producing some "dead" polymer and broadening the MWD (PDI TTOPS [approximately equal to] 1.14-1.24; final polymer PDI [approximately equal to] 1.3-1.8, depending on conditions).
This method works for condensation, free radical, and ionic polymerizations.