Crosslinking titanium - and zirconium chelates and their use.

摘要

Water-soluble N,N-bis-(2-hydroxyethyl)-glycine/metal chelates represented by the formula: CHEM wherein R is H or alkyl (1-12C); M is Ti or Zr; k is a number in the range between 0 and 1, p is a number in the range between 1 and 2, and k + p = 2 (in particular embodiments: k = 1 and p = 1; k = 0 and p = 2; and k = 0.5 and p = 1.5). The chelates can be used as cross-linking agents in hydraulic fracturing fluids and in gels that are used for selectively plugging permeable zones in subterranean formations or for plugging subterranean leaks.