formaldehyde - Sciencemadness Dot Org

Introduction
Formaldehyde chemistry is complicated by the fact that, although formaldehyde
is well known in the form of its aqueous solution? and solid
polymers, it is seldom encountered in pure monomelic form. Substances
with which the chemist must deal divide mainly in two groups: (I) compounds
with the type formula. (CHsOjn and (II) addition compounds or
solvates of which the most important are the simple hydrate, methylene
glycol (CH^OHV- and the hydrated linear polymers or polyoxymethylene
glycols whose type formula is HO-t'CHsOja-H. Group I includes formaldehyde
monomer itself, the relatively little known cyclic polymers,
trioxane—1.CH2OJ3 and tetraoxymethylenc—(CHsO)^ and the anhydrous
polyoxymethylene which is produced when monomelic formaldehyde
polymerizes. Group II includes (A) methylene glycol and the low molecular
weight polyoxymethylene glycols present in formaldehyde solutions,
(B'l the mixture of solid polyoxymethylene glycols known commercial^ as
paraformaldehyde, and (C) the so-called alpha-polyoxymethylenes,
HO-(CH^Ojn-H in which n is greater than 100- The anhydrous high
molecular weight polymer may be regarded as the end product of this
series. Polymeric compounds which are functional derivatives of polyoxymethylene
glycols are also occasionally encountered. All of these
hydrates, polymers, and polymer derivatives are reversible and react as
formaldehyde, differing only in the readiness with which they split up or
hydrolyze to yield formaldehyde or its simple reactive solvates.
In discussing formaldehyde chemistry, we shall first give attention to
the methods by which it is normally produced. Following this, we shall *
deal with the physical and thermodynamic properties of the various formaldehyde
substances: the simple monomer (Chapter II), formaldehyde
solutions (Chapters III-VI), and polymers (Chapter VII). Chapters
YIII-XV are devoted to the chemical properties of formaldehyde and its
reactions with various types of inorganic and organic chemicals. Chapters
XVI and XVII deal with formaldehyde detection and analysis.
Hexamethylenetetramine (Chapter XVIII), which is produced by the
reaction of formaldehyde and ammonia, must receive special consideration
in any discussion of formaldehyde substances. Although this compound,
(CH-2)eX4, is a distinct chemical entity, it plays an important industrial
role as a special form of formaldehyde. Chemically it'is an ammono analogue
of the cyclic formaldehyde polymers in which trivalent nitrogen has
replaced bfralent oxygen.
The industrial applications of commercial formaldehyde substances, viz.
formaldehyde solution, paraformaldehyde, and hexamethylenetetramine
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