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About: Polymerization is a(n) research topic. Over the lifetime, 147983 publication(s) have been published within this topic receiving 2711902 citation(s).
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01 Jan 1985-
Abstract: Cellular Materials Cellulose Cellulose, Biosynthesis Cellulose, Graft Copolymers Cellulose, Microcrystalline Cellulose Derivatives Cellulose Esters, Inorganic Cellulose Esters, Organic Cellulose Ethers Cement Additives Chain-Reaction Polymerization Chain Transfer Characterization of Polymers Charge-Transfer Complexes Chelate- Forming Polymers Chemical Analysis Chemically Resistant Polymers Chitin Chloroprene Polymers Chlorotrifluorethylene Polymers Chromatography Classification of Polymerization Reactions Coating Methods Coatings Coatings, Electrodeposition Cold Forming.

7,238 citations

Journal ArticleDOI
Abstract: This review aims at reporting on very recent developments in syntheses, properties and (future) applications of polymer-layered silicate nanocomposites. This new type of materials, based on smectite clays usually rendered hydrophobic through ionic exchange of the sodium interlayer cation with an onium cation, may be prepared via various synthetic routes comprising exfoliation adsorption, in situ intercalative polymerization and melt intercalation. The whole range of polymer matrices is covered, i.e. thermoplastics, thermosets and elastomers. Two types of structure may be obtained, namely intercalated nanocomposites where the polymer chains are sandwiched in between silicate layers and exfoliated nanocomposites where the separated, individual silicate layers are more or less uniformly dispersed in the polymer matrix. This new family of materials exhibits enhanced properties at very low filler level, usually inferior to 5 wt.%, such as increased Young’s modulus and storage modulus, increase in thermal stability and gas barrier properties and good flame retardancy.

5,682 citations

01 Jan 1981-
Abstract: Preface. 1. Introduction. 1.1 Types of Polymers and Polymerizations. 1.2 Nomenclature of Polymers. 1.3 Linear, Branched, and Crosslinked Polymers. 1.4 Molecular Weight. 1.5 Physical State. 1.6 Applications of Polymers. 2. Step Polymerization. 2.1 Reactivity of Functional Groups. 2.2 Kinetics of Step Polymerization. 2.3 Accessibility of Functional Groups. 2.4 Equilibrium Considerations. 2.5 Cyclization versus Linear Polymerization. 2.6 Molecular Weight Control in Linear Polymerization. 2.7 Molecular Weight Distribution in Linear Polymerization. 2.8 Process Condition. 2.9 Multichain Polymerization. 2.10 Crosslinking. 2.11 Molecular Weight Distributions in Nonlinear Polymerizations. 2.12 Crosslinking Technology. 2.13 Step Copolymerization. 2.14 High-Performance Polymers. 2.15 Inorganic and Organometallic Polymers. 2.16 Dendric (Highly Branched) Polymers. 3. Radical Chain Polymerization. 3.1 Nature and Radical Chain Polymerization. 3.2 Structural Arrangement of Monomer Units. 3.3 Rate of Radical Chain Polymerization. 3.4 Initiation. 3.5 Molecular Weight. 3.6 Chain Transfer. 3.7 Inhibition and Retardation. 3.8 Determination of Absolute Rate Constants. 3.9 Energetic Characteristics. 3.10 Autoacceleration. 3.11 Molecular Weight Distribution. 3.12 Effect of Pressure. 3.13 Process Conditions. 3.14 Specific Commercial Polymers. 3.15 Living Radical Polymerization. 3.16 Other Polymerizations. 4. Emulsion Polymerization. 4.1 Description of Process. 4.2 Quantitative Aspects. 4.3 Other Characteristics of Emulsion Polymerization. 5. Ionic Chain Polymerization. 5.1 Comparison of Radical and Ionic Polymerization. 5.2 Cationic Polymerization of the Carbon-Carbon Double Bond. 5.3 Anionic Polymerization of the Carbon-Carbon Double. 5.4 Block and Other Polymer Architecture. 5.5 Distinguishing Between Radical, Cationic, and Anionic Polymerizations. 5.6 Carbonyl Polymerization. 5.7 Miscellaneous Polymerizations. 6. Chain Copolymerization. 6.1 General Considerations. 6.2 Copolymer Composition. 6.3 Radical Copolymerization. 6.4 Ionic Copolymerization. 6.5 Deviations from Terminal Copolymerization Model. 6.6 Copolymerizations Involving Dienes. 6.7 Other Copolymerizations. 6.8 Applications of Copolymerizations. 7. Ring-Opening Polymerization. 7.1 General Characteristics. 7.2 Cyclic Ethers. 7.3 Lactams. 7.4 N-Carboxy-alphaAmino Acid Anhydrides. 7.5 Lactones. 7.6 Nitrogen Heterocyclics. 7.7 Sulfur Heterocyclics. 7.8 Cycloalkenes. 7.9 Miscellaneous Oxygen Heterocyclics. 7.10 Other Ring-Opening Polymerizations. 7.11 Inorganic and Partially Inorganic Polymers. 7.12 Copolymerization. 8. Stereochemistry of Polymerizaton. 8.1 Types of Stereoisomerism in Polymers. 8.2 Properties of Stereoregular Polymers. 8.3 Forces of Stereoregulation in Alkene Polymerization. 8.4 Traditional Ziegler-Natta Polymerization of Nonpolar Alkene Monomers. 8.5 Metallocene Polymerization of Nonpolar Alkene Monomers. 8.6 Other Hydrocarbon Monomers. 8.7 Copolymerization. 8.8 Postmetallocene: Chelate Initiators. 8.9 Living Polymerization. 8.10 Polymerization of 1,3-Dienes. 8.11 Commercial Applications. 8.12 Polymerization of Polar Vinyl Monomers. 8.13 Alehydes. 8.14 Optical Activity in Polymers. 8.15 Ring-Opening Polymerization. 8.16 Statistical Models of Propagation. 9. Reactions of Polymers. 9.1 Principles of Polymers Reactivity. 9.2 Crosslinking. 9.3 Reactions of Cellulose. 9.4 Reactions of Poly(vinyl) acetate). 9.5 Halogenation. 9.6 Aromatic Substitution. 9.7 Cyclization. 9.8 Other Reactions. 9.9 Graft Copolymers. 9.10 Block Copolymers. 9.11 Polymers as Carriers or Supports. 9.12 Polymer Reagents. 9.13 Polymer Catalysts. 9.14 Polymer Substrates. Index.

4,737 citations

Journal ArticleDOI
22 Jul 1998-Macromolecules
Abstract: mechanism involves Reversible Addition-Fragmentation chain Transfer, and we have designated the process the RAFT polymerization. What distinguishes RAFT polymerization from all other methods of controlled/living free-radical polymerization is that it can be used with a wide range of monomers and reaction conditions and in each case it provides controlled molecular weight polymers with very narrow polydispersities (usually <1.2; sometimes <1.1). Living polymerization processes offer many benefits. These include the ability to control molecular weight and polydispersity and to prepare block copolymers and other polymers of complex architecturesmaterials which are not readily synthesized using other methodologies. Therefore, one can understand the current drive to develop a truly effective process which would combine the virtues of living polymerization with versatility and convenience of free-radical polymerization.2-4 However, existing processes described under the banner “living free-radical polymerization” suffer from a number of disadvantages. In particular, they may be applicable to only a limited range of monomers, require reagents that are expensive or difficult to remove, require special polymerization conditions (e.g. high reaction temperatures), and/or show sensitivity to acid or protic monomers. These factors have provided the impetus to search for new and better methods. There are three principal mechanisms that have been put forward to achieve living free-radical polymerization.2,5 The first is polymerization with reversible termination by coupling. Currently, the best example in this class is alkoxyamine-initiated or nitroxidemediated polymerization as first described by Rizzardo et al.6,7 and recently exploited by a number of groups in syntheses of narrow polydispersity polystyrene and related materials.4,8 The second mechanism is radical polymerization with reversible termination by ligand transfer to a metal complex (usually abbreviated as ATRP).9,10 This method has been successfully applied to the polymerization of various acrylic and styrenic monomers. The third mechanism for achieving living character is free-radical polymerization with reversible chain transfer (also termed degenerative chain transfer2). A simplified mechanism for this process is shown in

4,324 citations

Journal ArticleDOI
01 Jan 1996-Advanced Materials
Abstract: Polymer nanocomposites with layered silicates as the inorganic phase (reinforcement) are discussed. The materials design and synthesis rely on the ability of layered silicates to intercalate in the galleries between their layers a wide range of monomers and polymers. Special emphasis is placed on a new, versatile and environmentally benign synthesis approach by polymer melt intercalation. In contrast to in-situ polymerization and solution intercalation, melt intercalation involves mixing the layered silicate with the polymer and heating the mixture above the softening point of the polymer. Compatibility with various polymers is accomplished by derivatizing the silicates with alkyl ammonium cations via an ion exchange reaction. By fine-tuning the surface characteristics nanodispersion (i. e. intercalation or delamination) can be accomplished. The resulting polymer layered silicate (PLS) nanocomposites exhibit properties dramatically different from their more conventional counterparts. For example, PLS nanocomposites can attain a particular degree of stiffness, strength and barrier properties with far less inorganic content than comparable glass- or mineral reinforced polymers and, therefore, they are far lighter in weight. In addition, PLS nanocomposites exhibit significant increase in thermal stability as well as self-extinguishing characteristics. The combination of improved properties, convenient processing and low cost has already led to a few commercial applications with more currently under development.

3,390 citations

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Topic's top 5 most impactful authors

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