Ring-Opening Polymerization of Macrocyclic Acetals

Synthesis and polymerization of cyclic formals of oligooxyethylene diols

“…A similar effect is found in the enthalpies of fusion which may well reflect differences in the extent of crystallization of the samples. For both quantities, the lower values are associated with the polymers with odd values of m. Even‐odd effect was observed also by other authors although reported values of T m were different 32 …”

“…For both quantities, the lower values are associated with the polymers with odd values of m. Even-odd effect was observed also by other authors although reported values of T m were different. 32 It should be pointed out that there is a significant difference in the behavior of uniform polymers prepared by polymerization of The high-molecular-weight polymers prepared from PEG200 were noncrystalline at room temperature, while those prepared from 1,3,6,9-tetraoxaundecene, with a regular chain structure, were crystalline (T m 30 C). 17 The main disadvantage of POE as a solid polymer electrolyte is its inherent crystallinity thus there is a search for amorphous POE analogs.…”

Reversible Cationic Polymerization of Trioxepane Resulting in Establishment of Stationary Concentrations of Three Monomers. Calculation of the Stationary Concentrations and of the Frequency of Various Triads

“…al. 1 plotted In [trioxepane]st vs. 1/T and obtained "apparent" ASss = -18.9 J/(mol deg) and AHaa = -6.6 kJ/mol. With the same data, a plot of In ([trioxepane]9t/r(l r)) vs. 1/T gives the thermodynamic entropy and enthalpy for polymerization of trioxepane to uniform polymer,6 viz., AS = -31.5 J/(mol deg) AH = -6.9 kJ/mol…”

“…An interesting paper describing cationic polymerization of 1,3,5-trioxepane was published recently by Schulz et al1 The following conclusions were derived from their observations: E 1,3,5-trioxepane (1) The investigated polymerization proceeds without termination, i.e., it yields living polymers.…”