| 摘要 |
PURPOSE:To produce a soil conditioner exhibiting at least the same granulation effect as that of an acrylate slat, by compounding chitosan and tannin, optionally together with an amino acid, with polyvinyl alcohol. CONSTITUTION:A soil conditioner comprising polyvinyl alcohol, chitosan, and tannin. An amino acid is pref. added to the above compsn. to further increase the granulatability of the soil conditioner. The proportions of the components are pref. such that the compsn. contains 7-8wt.% polyvinyl alcohol, 0.1-0.3wt.% tannin, 0.5-2wt.% chitosan, and 0.1-0.6wt.% amino acid. This soil conditioner can be prepd., by e.g., the following method. First, an aq. soln. (A) is prepd. with contains polyvinyl alcohol and tannin (an amino acid added if desired) in the above proportions. Separately, a chitosan soln. (B) having a concn. of about 0.5-2wt.% is prepd. by dissolving chitosan in an acid soln. (e.g., hydrochloric acid, acetic acid, etc.). Then, the solns. A and B are mixed together in vol. proportions of above 8:1, and the pH value of the mixture is adjusted to about 6-8.
|
