Ring-opening polymerizations commercially important

Cyclic ether and acetal polymerizations are also important commercially. Polymerization of tetrahydrofuran is used to produce polyether diol, and polyoxymethylene, an excellent engineering plastic, is obtained by the ring-opening polymerization of trioxane with a small amount of cycHc ether or acetal comonomer to prevent depolymerization (see Acetal resins Polyethers, tetrahydrofuran). 

Ring opening polymerization produces a small number of synthetic commercial polymers. Probably the most important ring opening reaction is that of caprolactam for the production of nylon 6 ... 

In addition to step and chain polymerizations, another mode of polymerization is of importance. This is the ring-opening polymerization (ROP) of cyclic monomers such as cyclic ethers, acetals, amides (lactams), esters (lactones), and siloxanes. Ring-opening polymerization is of commercial interest in a number of systems, including the polymerizations of ethylene oxide... 

The ring-opening polymerizations of heterocyclic compounds are important, not least because of the number of commercial polymers produced in this way. The best-known examples include Nylon 6, which is produced from e-caprolactam as shown in Scheme 16 poly(ethylene oxide) produced by ring-opening polymerization of ethylene oxide (or oxirane), a route to which is described in Protocol 14 (Scheme 17), and poly(dimethylsiloxane) which is formed from a cyclic tetramer produced on hydrolysis of dimethyl-silyldichloride in a way similar to that described in Protocol 15. 

Some Commercially Important Ring Opening Polymerizations... 

Table 10.1 Commercially Important Polymers Prepared by Ring-Opening Polymerization...

The most important limitation related to commercial applications is relatively low reactivity of epoxide-based resins, commonly used in coatings, compared to acrylate based systems. Therefore, most works have been effort to accelerate ring-opening polymerization of epoxides. There are four different strategies to speed up the polymerization ... 

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