A Novel Route to Thermosensitive Polymeric Core–Shell Aggregates and Hollow Spheres in Aqueous Media

Poly(e-caprolactone)/poly(N-isopropylacrylamide) (PCL/PNIPAM) core–shell particles are obtained by localizing the polymerization of NIPAM and crosslinker methylene bisacrylamide around the surface of PCL nanoparticles. The resultant particles are converted to hollow PNIPAM spheres by simply degrading the PCL core with an enzyme. The hollow spheres are thermosensitive and display a reversible swelling and de-swelling at ∼ 32 °C.

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