EG bishemiformal

The addition of formaldehyde to ethyleneglycol = EG (1.13.) leads to EG-hemiformal (3.1.4a.) and EG-bishemiformal (3.1.4b.). Under acidic conditions water is eliminated from the EG-hemiformal and the formal 1,3-dioxolane (3.1.4c.) is formed (see Figure 8). 

The addition of formaldehyde to ethylene glycol leads to mono- and bishemiformal of ethylene glycol with microbicidal efficacy (Fig. 20). Under acidic conditions water is eliminated from the EG hemiformal and ethyleneformal is formed, the formaldehyde content of which is not detectable with the Tannenbaum method. Accordingly 1,3-dioxolane does not exhibit substantial antimicrobial effectiveness. 

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