Copolymerization Of Cyclic Ethers Research Articles

Update and Challenges in Carbon Dioxide-Based Polycarbonate Synthesis.

The utilization of carbon dioxide as a comonomer to produce polycarbonates has attracted a great deal of attention from both industrial and academic communities because it promises to replace petroleum-derived plastics and supports a sustainable environment. Significant progress in the copolymerization of cyclic ethers (e.g., epoxide, oxetane) and carbon dioxide has been made in recent decades, owing to the rapid development of catalysts. In this Review, the focus is to summarize and discuss recent advances in the development of homogeneous catalysts, including metal- and organo-based complexes, as well as the preparation of carbon dioxide-based block copolymer and functional polycarbonates.

Recent Progress in the Copolymerization of Cyclic Ethers and Cyclic Anhydrides via Organocatalysts

Recent Progress in the Copolymerization of Cyclic Ethers and Cyclic Anhydrides via Organocatalysts

Effect of the reaction medium on the kinetics and mechanism of the cationic polymerization and copolymerization of cyclic ethers

The effect of the reaction medium on the kinetics and mechanism of cationic polymerization and copolymerization of cyclic ethers is considered. It is shown that a change in the conditions of solvation of reaction sites by the components of the system, leading to a substantial effect on the characteristics of the course of the process, may be achieved not only by a change in the nature of the solvent, but also by the introduction into the reaction mixture of small additions of substances that preferentially solvate the cation or anion or both the oppositely charged ends of the active site that exists as a cyclic zwitter ion pair.

The role of water in the copolymerization of cyclic ethers

The general mechanism of action of water in the cationic polymerization of cyclic ethers on the molecular weigth (mol.wt.), composition and polydispersity of the products has been investigated. Water was found not to participate in the production of an active catalyst up to a certain concentration, not to cause decay, but to be utilized in the production of the hydroxyl end groups of the copolymer.

Copolymerization of cyclic ethers with vinyl compounds. V. Reaction of polyethers in cationic polymerization of styrene

AbstractPolymerization of styrene was carried out in presence of polyethers at 30°C in benzene solution using borontrifluoride etherate as a catalyst. The polymerization was retarded in the presence of polyethylene oxide. At the same time, the degradation of polyethylene oxide and chain transfer reaction were found to undergo under our conditions.The chain transfer constants of polyethers were determined and the contribution of each functional group of the chain was estimated.

Copolymerization of cyclic ethers with vinyl compounds. II. Effects of copolymerization conditions on cationic copolymerization of epichlorohydrin with styrene

AbstractCationic copolymerization of epichlorohydrin with styrene was carried out under various conditions. The copolymer obtained was fractionated into two fractions: one was a methanol‐soluble liquid, and the other was a methanol‐insoluble solid polymer. The liquid polymer was found to be very rich in epichlorohydrin and the solid one was on the contrary very rich in styrene. The effects of catalysts, catalyst concentration, polymerization temperature and some other conditions on the copolymerization were investigated.

Copolymerization of cyclic ethers with vinyl compounds. I. Copylymerization of epichlorohydrin, with styrene

AbstractThe copolymerization of epichlorohydrin with styrene borontrifluoride etherate was studied in benzene solution. The copolymer is a white solid completely soluble in common organic solvents. The epichlorohydrin content in the copolymer decreases rapidly at the initial stage of copolymerization and then gradually with polymerization time. It is considered that epichlorohydrin at first reacts rapidly with the catalyst to form a soluble polymer rich in epichlorohydrin. When the concentration of epichlorohydrin becomes low, the styrene takes part in the reaction owing to its increasing concentration. Although formation of homopolymeric polyepichlorohydrin must be considered, free polystyrene could not be found; this was confirmed by turbidity investigations of the copolymers.

Preparation of alternating copolymer, by copolymerization of cyclic ethers which have no homopolymerizability

Preparation of alternating copolymer, by copolymerization of cyclic ethers which have no homopolymerizability

Cationic copolymerization of cyclic ethers which have no homopolymerizability

Cationic copolymerization of cyclic ethers which have no homopolymerizability

Copolymerization of cyclic ethers by alkylaluminum catalysts

AbstractCopolymerization of cyclic ethers was carried out with triethylaluminum (AlEt3) or AlEt3:H2O = 1:1 catalysts. The monomer combinations are 3,3‐bis(chloromethyl) oxacyclobutane (BCMO) — totrahydrofuran (THF) and epichlorhydrin (ECH) —THF. For BCMO — THF promoters such as propylene oxide or ECH or cocatalysts such as acetyl chloride or α‐chlorodimethyl ether were required in order to perform the copolymerization over a wide range of monomer composition. In both cases, the formation of copolymers was established by solubility characteristics and analysis of the product. In the case of ECH — THF, however, a considerable amount of crystalline ECH homopolymer was formed; and this observation was taken to suggest that the catalyst species of this copolymerization were not of uniform character.