A series of amphiphilic co-networks (ACNs) is prepared in a straightforward way via thiolactone chemistry by crosslinking a multivalent thiolactone-functional poly(dimethylsiloxane) building block with poly(ethylene glycol) diacrylates. Formation of the networks is triggered by the addition of an amine, of which the nucleophilicity and steric bulk control the curing kinetics. Furthermore, some of the crosslinks can be sacrificed to introduce a fluorescent group or dye via a thia-Michael addition, without affecting the bulk mechanical properties and swelling capabilities. The obtained ACNs exhibit a unique set of properties because of their nanophase separation, resulting in hydrophilic PEG and hydrophobic PDMS phases. Hence, swelling in both water and organic solvents is observed, of which the extent can be tuned by varying the overall PEG content. (c) 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 322-333