N-acylurea and O-acylisourea derivatives of hyaluronic acid
申请人:THE RESEARCH FOUNDATION OF
STATE UNIVERSITY OF NEW YORK
公开号:EP0416250A2
公开(公告)日:1991-03-13
N-Acylureas and O-acylisoureas prepared by the reaction of a carbodiimide or a biscarbodiimide with hyaluronic acid are useful as vitreous replacements, joint cushions or adjuncts in wound healing.
Compositions containing water control treatments and formation damage control additives, and methods for their use
申请人:Dawson C. Jeffrey
公开号:US20060065396A1
公开(公告)日:2006-03-30
The present invention relates to compositions of aqueous compositions comprising relative permeability modifier (RPM) macromolecules and one or more formation damage control additives, for use in treating hydrocarbon-producing wells, formations, and equipment, as well as methods for the use of such compositions. Such compositions, comprising the RPM macromolecule and the one or more formation damage control additive, such as a scale control agent, can result in the formation of a composition wherein the components exhibit a “synergistic” effect, whereby the ability of the formation damage control additive to prevent formation damage is enhanced relative to the use of the same additive separately.
Methods and compositions for stimulating single and multiple intervals in subterranean wells by diverting well treatment fluids into a particular direction or into multiple intervals using water soluble coated diverting agents are described. The water soluble coating of the diverting material is preferably a collagen, poly(alkylene) oxide, poly(lactic acid), polyvinylacetate, polyvinylalcohol, polyvinylacetate/polyvinylalcohol polymer or a mixture thereof applied as a coating on any number of proppants. The method allows for the diverting of the flow of fluids in a downhole formation during a well treatment, such as during a fracturing process. Following completion of a treatment such as a hydraulic stimulation, the soluble diverting agent can be dissolved and removed by the water component of the well production.