Urea → Phenol-Formaldehyde Urea

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Samples of phenol-formaldehyde resole (herein referred to as “Comparative Example 3a”) and phenol-formaldehyde resole modified with urea-formaldehyde condensate prepared according to Example 2 (herein referred to as “Example 3b”) were made to premix solutions in the following manner: To each of these solutions, a 50% solids solution of urea was added to give a final ratio of about 37 wt % added urea to about 63 wt % resin solids, for a total of about 240 g of both the Comparative Example 3a resin mix and the Example 3b resin. Each was mixed until the urea dissolved. Each of these solutions was then seeded with a catalytic amount (0.15 g) of isolated tetradimer, and the solutions were slowly agitated at 75-77° F. (24-25° C.) to simulate a customer's mix tank.

Herkunft & Nachweise