Thermally stable high molecular weight polyoxymethylenes

Abstract

In this, the first of a series of five papers, the historical development of formaldehyde polymers, beginning with the work of Butlerov and continuing through the investigations of Staudinger and his collaborators, is reviewed. Recent studies in these laboratories have led to thermally stable high polymers of formaldehyde. Initiators and the role of impurities in the polymerization are described. An explanation is offered to account for differences in thermal stabilities between old and new polymers. Esterification, by which further increases in thermal stability are achieved, is described. It is proposed that the generic term “acetal resin” be used to described high polymers that are composed of repeating oxymethylene units.

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

“…There are two routes for the production of polyacetal resin. 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.…”

Investigation of the thermal decomposition properties of polyoxymethylene

“…Because of excellent friction and wear property, dimensional stability and chemical stability, POM is widely used to produce self-lubricating mechanical parts in auto, electronic and precision machine industries [1][2][3] . However, the thermal stability of POM is not good and the processing condition is harsh, therefore the ageing resistance of POM is focussed on and many progresses have been reported [4][5][6][7] .…”

Polyoxymethylenes

“…In particular esterification with acetic anhydride has become industrially important [2]. The reaction can, for example, be carried out in the presence of small amounts of sodium acetate as catalyst in boiling acetic anhydride.…”

“…Terminal-group-stabilized homopolymers of formaldehyde with adequate thermal stability were first developed by DuPont [2,[48][49][50].…”