A new chemical product, that is, photoreversibly switchable hydrophobic surface coating, was synthesized by atom transfer radical polymerization and graft-from method based on molecular design. Focusing on the strategy of new product development from the chemical product engineering perspective, the product characterization, switching mechanism analysis, performance evaluation, and model interpretation were carried out to confirm the new product manufacture and to ensure the product application with a following aging test. The results show that the product enables surfaces to have reversibly switchable wettability and excellent stability after a month-long test with eight irradiation cycles. Additionally, the wetting behavior of silicon surface can be tuned between hydrophilicity and hydrophobicity based on blank sample using the surface engineering technique (decorated with functional film and surface roughening). The product presented here can be utilized for constructing a hydrophobic surface with photo-induced controllable wettability in moisture-resistance, and it also offers a new technique for the manipulation of liquids in microfluidic devices. (c) 2014 American Institute of Chemical Engineers AIChE J 60: 4211-4221, 2014