In FIG. 8A, the TGA result of silica micro capsules shows that the residual amount is 82.5%. After hetero-coagulation of poly-NIPAM latex particles with silica capsules, it is shown in FIG. 8B that the residual amount decreased to 6 1%. Therefore, this indicated that the content of poly-NIPAM latex adsorbed on the silica capsules is approximately 20%. Scanning electron microscopy of sub-20 micron hetero-coagulated silica capsules with poly-NIPAM latex particles To further prove that the hetero-coagulation was successfully achieved, the inventors performed synthesis of sub-20 micron silica capsules using CTAB as the surfactant, which are not breakable under SEM, i.e. able to withstand the vacuum condition used for SEM imaging. SEM images were obtained at various stages of the polymer coating process (see FIG. 9A, FIG. 9B and FIG. 9C). Based on the SEM images, it is shown very clearly that the inventors were able to coat a uniform layer of polymer around the silica capsules. Analysis of the silica capsules vs. poly-NIPAM coated silica capsules using dark field microscopy and TGA proved that the hetero-coagulated silica capsules with poly-NIPAM latex particles synthesized in the examples are spherical micro- capsules having uniform size distribution with approximately 20% temperature responsive poly-NIPAM coating. Poly-NIPAM is also reported to be salt- responsive. Example 5: Fletero-coagulation of Organic Polymer Latex Particles (i.e. polvcaprolactone) with Primary Capsule(s) In this example, hetero-coagulation experiments were carried out using polycaprolactone particles as the organic polymer latex particles and silica capsules as the primary capsule(s).