The methylol urea compounds referred to earlier are truly, if only slightly water soluble, that is to say, the more solvent (water) that is added, the greater the weight of solute dissolved. On the other hand, the resinous liquids used as adhesives are not true solutions but colloidal dispersion, and although it is possible to produce dispersion that are infinitely compatible with water, the reaction products used as adhesives are not generally of this type.
The extreme case of a resin having infinite compatibility with water at all temperatures is an indication that the resin having infinite compatibility with a high ratio of formaldehyde (and probably smells strongly of it), or that it has been relatively under reacted. Formaldehyde also have common name as formalin, this substance is very smell and can irritate our respiratory system. The smell of formalin still hard even have convert into urea formaldehyde resin.
More about Water Toleration for UF
No comments:
Post a Comment