Guar gum needs to be thin enough to make it easier to pump. Then as it flows down the pipe, the fluid needs to gel up to support the proppant and flush it deep into the fractures. After that process, the gel has to break down so we can flow back and recover the fracking fluid, but leave the proppant behind. This requires a chemical process which produces then breaks the gel cross-linking at a predictable rate. Guar+boron+proprietary chemicals can accomplish both of these goals at once. Guar gum retards ice crystal growth nonspecifically by slowing mass transfer across the solid/liquid interface.
Guar Guar The Guar or cluster bean, with the botanical name Cyamopsis tetragonoloba, is an annual legume and the source of guar gum. It is also known as Gavar, Guwar, or Guvar bean. The origin of "Cyamopsis tetragonoloba" is unknown, since it has never been found in the wild. It is assumed to have developed from the African species "Cyamopsis senegalensis". It was further domesticated in India and Pakistan, where it has been cultivated for many centuries. Guar grows well in semiarid areas, but frequent rainfall is necessary. This legume is a very valuable plant within a crop rotation cycle, as