Cationic Ring Opening Polymerization of Glycolide Catalysed by a Montmorillonite Clay Catalyst

Comparison of the growth and degradation of poly(glycolic acid) and poly(ε-caprolactone) brushes

“…This explanation has been advanced for a very similar, observed decrease in the thickness of PLA brushes during polymerization at elevated temperatures . a Depolymerization has also been reported to be favored at elevated temperatures for PLA and PGA in solution …”

Influence of clay type on exfoliation, cure and physical properties of in situ polymerised poly(methyl methacrylate) nanocomposites

“…In order to study the possible effects of the clay on the cure process it was first desirable to ensure that the PMMA/MMA mixture was not susceptible to polymerisation by the clay over the typical period of the curometer measurements. It is well known that ultrasonication of polymers in solution can lead to degradation and hence the possibility of creating free radicals which could initiate polymerisation 22–24. Curometer measurements indicated that ultrasonically dispersed Cloisite 30B, Cloisite 20A, Cloisite 15A and Cloisite Na + did not cure perceptibility over a period of 16.7 h, indicating that the dispersion process did not create long‐lived species which can initiate polymerisation.…”

“…Cloisite 30B has 90 meq (100 g) −1 of a modifier which contains two hydroxyl groups on the head group which should bind the modifier tightly to the surface, Cloisite 20A has 95 meq (100 g) −1 of a modifier which only has alkyl groups and will be less effectively bound to the surface and Cloisite 15A has a higher level of substitution of the alkyl modifier at 125 meq (100 g) −1 . Previous work22–24 has demonstrated the use of proton‐exchanged montmorillonite as a catalyst in cationic polymerisation reactions. The apparent lack of reaction in the initial dispersions indicates that neither cationic nor anionic polymerisation appears to be initiated even in the case of the Cloisite Na + clay.…”

Polyglycolide–montmorillonite as a novel nanocomposite platform for biosensing applications

“…22 Also, different from our study, using the montmorillonite clay mineral as a catalyst for the polymerization of glycolide was reported. 23 Nanocomposites have some advantages for use in bio-related areas because of their flexibility, biocompatibility and higher mechanical stability. Furthermore, a Biochemistry Department, Faculty of Science, Ege University, 35100 Bornova-Izmir, Turkey.…”