| 摘要 |
A polymer viscosifying agent for wellbore fluids, is formed through polymerisation of at least two pre-polymers, "A" preferably being a polysaccharide containing chemically reactable primary and secondary groups (which may be hydroxyl, amino, aldehyde, formyl, epoxy, ester or amide groups), an example of such a polysaccharide is depolymerised guar gum, and "B", preferably being poly(ethyleneadipate) tolyene 2-4-diisocyanate, polyethylene glycol bismethacrylate. The polymer viscosifying agent preferably degrades into soluble fragments after initiation of a breaking process, and wherein sub-chains of the pre-polymer "A" provide more than 50% of the molecular mass of the polymer. |
