Epoxide monomers, physical properties

He concluded that this remarkable difference in physical properties resulted from identical configuration of all the asymmetric centers in the crystalline polymer. The liquid polymer from racemic monomer, on the other hand, was evidently a stereorandom atactic polymer (4). Both polymers were later shown to be formed almost exclusively by head-to-tail polymerization. Vandenberg, Price, and others later showed that addition of each epoxide unit to the polymer chain occurs with inversion of configuration at the carbon atom where ring opening occurs. The asymmetry in this case is not disturbed, however, because the bond between the oxygen and the asymmetric carbon is never broken. 

A premium family of fire retardants is based on reactive compounds that are able to enter into the polymer chain during the polymerization process (mainly polyesters, epoxides and polyurethanes), or monomers that contain fire-retardant groups (like bromo-styrene). Due to their relative physical stability (regarding diffusivity to the atmosphere), the advantage over additives is clear. In this case, it is also important to study the effects on mechanical and optical properties and mainly on weather resistance. 

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