| 摘要 |
A process of preparing beads of urea-formaldehyde resin in which disperse particles of an aqueous urea-formaldehyde syrup are converted to hard polymer and azeotropically dehydrated. The aqueous syrup must have a solids content of at least 65% by weight and the mol ratio of formaldehyde to urea must be within the range of 1.9 - 2.3 to 1. |
