CPC C09K 8/588 (2013.01) [C09K 8/508 (2013.01); C09K 8/512 (2013.01); C09K 8/516 (2013.01); E21B 33/138 (2013.01); E21B 43/20 (2013.01); C09K 2208/10 (2013.01)] | 19 Claims |
1. A controlled-release delivery particle comprising:
an outer shell defining an interior core, the outer shell being at least partially formed of a degradable polymer selected from the group consisting of polyureas, polyurethanes, and combinations thereof; and
one or more materials present in the interior core and releasable from the controlled-release delivery particle;
wherein the controlled-release delivery particle has an average size of about 50 nm to about 900 nm; and
wherein the controlled-release delivery particle is configured for delivery to a site of use exhibiting one or more conditions effective to cause the outer shell to degrade from the outside-in and release the one or more materials from the interior core, the one or more conditions effective to cause the outer shell to degrade comprising one or more of pH, temperature, pressure, salinity, shear, and oil content.
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