Chemistry Reference
In-Depth Information
1,3-trioxopane, a product of condensation of trioxane with ethylene oxide, can be polymerized by
cationic mechanism both in solution and in bulk [
84
]:
O
O
OO
O
n
O
Polymerizations, carried out with boron trifluoride catalyst in dichloroethane solvent result in
several reactions that occur simultaneously [
84
]:
O
O
O
O
OO
+
O
n
O
O
O
O
+
copolymer
HH
At low temperatures the amount of dioxolane that forms in the above reaction decreases consider-
ably and can become zero.
Ring-opening polymerizations of trioxocane result in the following polymer [
84
,
85
]:
O
OO
O
n
O
O
So far, the nature of the end groups has not been established. Nor has it been shown that a
macrocyclic structure does not form.
1,3,6,9-tetraoxacycloundecane (triethylene glycol formal) can be polymerized can be polymerized
by several cationic initiators in solution or in bulk at varying temperatures from
30 to +150
C[
84
]:
O
O
O
O
3
n
O
O
5.8 Polymerization of Lactones
Polymerization of lactones can be carried out by three mechanisms, namely, cationic, anionic, and
coordinated one. Often, the mechanism by which a specific lactone polymerizes depends upon the
size of the ring.
5.8.1 Cationic Polymerization
Cationic polymerizations of lactones has been carried out with the help of alkylating agents, acylating
agents, Lewis acids, and protonic acids. Various reaction schemes were proposed to explain the
