| 摘要 |
The invention relates to a process for preparing urea-formaldehyde adhesives with a low content, of 15% at the most, of free formaldehyde, employed in wood industry for manufacturing chipboards and plywood, consisting of the condensation of the formaldehyde with urea in three stages: the methylol stage in an alkaline medium, the methylene stage in an acid medium and the polycondensation stage in an alkaline medium.
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