Polymerization of Trioxane

Abstract

A survey of the possible modes of' polymerization of trioxane is followed by a discussion of current ideas concerning the course of the polymerization. The polymerization, which involves ring cleavage, is characterized by a number of side reactions of the growing polyoxymethylene cations, such as chain transfer, transacetalization, and hydride shift.These reactions not only determine the nature of the endgroups and the molecular weight of the resulting polyoxyrnethylenes, but are also responsible for their chemical and molecular uniformity. Special emphasis is placed on the role of the monomeric formaldehyde formed during the polymerization of trioxane. The polyoxymethylenes obtained by the cationic polymerization of trioxane are similar in structure to those obtained by the cationic polymerization of formal- Polymerization of

Synthesis of copolymer from 1,3,5‐trioxane and 1,3‐dioxolane catalyzed by Maghnite‐H+

“…Several problems may occur during this bulk process. The heat of polymerization of TOX is close to 4.0 Kcal/mol 23 and this heat has to be removed.…”

“…One route is the polymerization of formaldehyde (acetal homopolymer), [1][2][3][4][5][6] and the other method is copolymerization of trioxane with cyclic ethers or acetals (acetal copolymer), preferably with 1,3-dioxolane [7][8][9][10] or ethylene oxide. [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28] The copolymerization of trioxane is of considerable industrial importance, because the acetal copolymer has better thermal properties and superior resistance to alkali than homopolymer and it is a commercially useful engineering plastic.…”

Kinetics and mechanism of the cationic polymerization of trioxane. II. Consideration of hydride transfer

“…The hydride ion in the transfer reaction may be from the middle of an adjacent polymer molecule, from the end of the same molecule, or even from trioxane. 1,4,6 Rate constants for these transfer reactions rarely have been published.…”

“…Only cationic polymerization takes place in trioxane, whereas formaldehyde can be polymerized either anionically or cationically. 1 Trioxane can be polymerized in the solid state, melt, gas phase, suspension, and solution. In solution polymerization (precipitation polymerization), polyoxymethylene does not dissolve in the reaction mixture, so that, after the induction period, phase separation accompanying crystallization occurs.…”

Future, Environmental Impact and Suppliers

“…Since the terminal structure derived from the comonomer significantly aff ects the heat stability of the copolymer, the examination of various comonomers has been reported. Although uses have been reported for an epoxy compound [15][16][17], cyclic formal [15][16][17][18][19], vinyl compound [18][19][20], lactone [21], and lactam [21] as the comonomer, ethylene oxide and cyclic ethers are generally manufactured on a commercial basis as the comonomers for trioxane, and the amount of comonomers is said to be about 2 mol% [22].…”