Given the demand for plastic products, solving the problem of plastic waste is urgent. To alleviate this, biodegradable plastics are replacing conventional plastics; however, their biodegradation rates are often low. While engineering plastics with low-surface-energy silicon-containing lubricants provide broad liquid repellency, the limited moisture permeability slows biodegradation. A long-standing challenge is to combine the conflicting requirements of waterproofness and breathability within a single platform. Here, for the first time, we propose a new class of self-lubricative, omniphobic, covalently attached liquid coating that harnesses the dual mechanisms of both physical and chemical cross-linking. This coating was achieved by the cohydrolysis and co-condensation of linear polydimethylsiloxane (PDMS) blocks and silicone oil onto noncommercial plastics via a facile, cost-effective, and industrially feasible spray-coating technique. The superior smoothness and the interfacial slippage arising from the synergistic lubrication effects between the PDMS and silicone oil enable a wide range of both polar and nonpolar liquids to slide easily. Diffusion of silicone oil into the porous PDMS skeleton improved the breathability (180 g m-2 per day) and led to pronounced biodegradation (33% mass loss in 10 weeks). This work provides proof-of-concept data for constructing biodegradable coatings on plastics, which may have significant applications in biomedical settings.
Ghasemlou et al. (Wed,) studied this question.