Making plastics from carbon dioxide: salen metal complexes as catalysts for the production of polycarbonates from epoxides and CO2.

Most synthetic polymers are made from petroleum feedstocks. Given the non-renewable nature of these materials, there is increasing interest in developing routes to polymeric materials from renewable resources. In addition, there is a growing demand for biodegradable polymeric materials. Polycarbonates made from CO(2) and epoxides have the potential to meet these goals. Since the discovery of catalysts for the copolymerization of CO(2) and epoxides in the late 1960's by Inoue, a significant amount of research has been directed toward the development of catalysts of improved activity and selectivity. Reviewed here are well-defined catalysts for epoxide-CO(2) copolymerization and related reactions.

Discrete Metal-Based Catalysts for the Copolymerization of CO2 and Epoxides: Discovery, Reactivity, Optimization, and Mechanism

Kinetic of crystallization from the melt and chain folding in polyethylene fractions revisited: theory and experiment

http://petrops.com/files/article_pdf/article1.pdf

Recycling of PET

Carbon dioxide is an important carbon source in the atmosphere and is “problematic” toward the activities of human beings. Although carbon dioxide is a cheap, abundant and relatively nontoxic C1 source, its chemical transformations have not been widely developed so far and are still far from synthetic applications, especially in the construction of the C–C bond. This critical review summarizes the recent advances on transition-metal-catalyzed C–C bond formation through the fixation of carbon dioxide and their synthetic applications (124 references).

Transition-metal-catalyzed C–C bond formation through the fixation of carbon dioxide

The γ-phase of high molecular weight isotactic polypropylene: III. The equilibrium melting point and the phase diagram

The γ-phase of high molecular weight isotactic polypropylene. II: The morphology of the γ-form crystallized at 200 MPa

A homologous series of aliphatic polycar- bonates with different side-chain lengths was synthesized by ring-opening polymerization of terminal epoxides with CO2 using zinc adipionate as catalyst (patented process of Empower Materials (formerly PAC Polymers Inc.)). Addi- tionally, a polycarbonate was made having a cyclohexane unit in its backbone, together with a terpolymer having both cyclohexane and propylene units. After characterization of thermal properties the aliphatic polycarbonates were found to be completely amorphous. Polycarbonates derived from long-chain epoxides showed a glass-transition temperature (Tg) below room temperature, whereas polycarbonates de- rived from cyclohexene oxide showed a Tg of 105°C, the highest yet reported for this class of polymers. The initial decomposition temperature of the polymers in air and ni- trogen atmospheres was found to be less than 300°C. The mechanical properties and the dynamic mechanical relax- ation behavior of the polymers were also reported. The effect of the chemical structure on the physical properties of ali- phatic polycarbonates was discussed. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1163-1176, 2003

Physical properties of aliphatic polycarbonates made from CO2 and epoxides

The gamma phase of high-molecular-weight polypropylene: 1. Morphological aspects

This book is an introduction to polymers and focuses on the synthesis, structure and properties of the individual molecules that constitute polymeric materials. It approaches polymeric materials from a molecular basis on the belief that there is a common core of knowledge and principles concerning polymer molecules that can be set out in an introductory work. Subjects treated include an introductory overview of synthesis, an introduction of the concept and definition of molecular weight and its distribution, experimental methods for measuring molecular weight, a more detailed view of polymerization including kinetics and mechanism, and the three-dimensional architecture of polymers as determined by conformation and stereochemistry. The statistical description of the conformational disorder of the molecules is covered and then built upon in treating rubber elasticity and polymer solutions.

Paul J. Phillips

Papers

The γ-phase of high molecular weight isotactic polypropylene: III. The equilibrium melting point and the phase diagram

The γ-phase of high molecular weight isotactic polypropylene. II: The morphology of the γ-form crystallized at 200 MPa

Physical properties of aliphatic polycarbonates made from CO2 and epoxides

The gamma phase of high-molecular-weight polypropylene: 1. Morphological aspects

The Science of Polymer Molecules