| 摘要 |
<p>A delayed crosslinking agent for polysaccharides is a dry granular composition containing a borate source and a water-soluble polysaccharide. The borate source is preferably borax, boric acid or sodium tetraborate. Guar gum, carboxymethylhydroxypropylguar, and hydroxypropylguar are suitable water-soluble polysaccharides. The borate source, calculated as B2O3, is present in an amount of from 5 to 30% by weight of the water-soluble polysaccharide.</p> |
