The invention relates to a preparation method of a
formaldehyde-
free water-resistant
protein adhesive. The main preparation steps are as follows: 1) activating a
protein raw material: adding the
protein-containing
raw material and absolute
ethanol, stirring, further adding an alkaline solution, and heating to 45-80 DEG C for reaction; cooling to
room temperature and adding a
reducing agent; and adjusting to neutral, and evaporating to
dryness to obtain activated protein
powder; and 2) preparing the protein
adhesive: adding the activated protein
powder prepared in the step 1, water, an acid-adjusting
reagent, an
enhancer and a
preservative into a reactor, reacting at the temperature of 30-50 DEG C, and reducing to
room temperature to obtain the protein
adhesive. The preparation method is characterized in that a special
protein activation process is adopted to enable proteins to
expose active groups thereof and utilize a variety of active functional groups of the proteins to the greater extent; the preparation process of the adhesive is simple and has the advantages of good reproductivity, low cost, no
formaldehyde and good
water resistance; and a
hot pressing process is the same with an existing
urea-
formaldehyde resin pressure plate process, on the basis of not changing and increasing the
hot pressing process and equipment, the production of formaldehyde-free artificial plates can be realized, and the market prospects are greater in comparison with the existing protein adhesive in industrial production.