PNIPAM-MAPOSS Hybrid Hydrogels with Excellent Swelling Behavior and Enhanced Mechanical Performance: Preparation and Drug Release of 5-Fluorouracil

Poly(N-isopropylacrylamide) (PNIPAM) is a widely-studied polymers due to its excellent temperature sensitivity. PNIPAM-MAPOSS hybrid hydrogel, based on the introduction of acrylolsobutyl polyhedral oligomeric silsesquioxane (MAPOSS) into the PNIPAM matrix in the presence of polyethylene glycol, was prepared via radical polymerization. The modified hydrogels exhibited a thick, heterogeneous porous structure. PEG was used as a pore-forming agent to adjust the pore size. MAPOSS reduced the swelling ratios of gels, and decreased the LCST, causing the hydrogels to shrink at lower temperatures. However, its hydrophobicity helped to improve the temperature response rate. The incorporation of rigid MAPOSS into the polymer network greatly increased the compressive modulus of the hydrogel. It is worth noting that, by adjusting the amount of MAPOSS and PEG, the hydrogel could have both ideal mechanical properties and swelling behavior. In addition, hydrogel containing 8.33 wt % MAPOSS could achieve stable and sustained drug release. Thus, the prepared PNIPAM-MAPOSS hybrid hydrogel can serve as drug carrier for 5-fluorouracil and may have potential application in other biomedical fields.