Patent ID: 11859065
Assignee: KING FAISAL UNIVERSITY
Field: Basic materials chemistry (Chemistry)
Classification: CPC C | IPC C

Claim 10:
11. A freestanding superhydrophobic sheet produced according to a method comprising:
dissolving polypropylene (PP) isolated from plastic waste in a solvent to form a clear hot polypropylene solution;
pre-heating a solid substrate to a temperature below a boiling point of the solvent;
applying the clear hot polypropylene solution onto the heated solid substrate followed by spin casting for a time in the range of 30 seconds to 10 minutes, at a speed ranging from 300 to 3500 rpm, followed by annealing to a temperature above a melting point of the polypropylene to obtain a hot, strong, nonporous base layer having a thickness of about 3 μm to about 170 μm; and
applying another layer having a thickness of about 7 μm to about 170 μm of the clear hot polypropylene solution onto the hot, strong, nonporous base layer through spin casting for a time in the range of 30 seconds to 10 minutes, at a speed ranging from 300 to 3500 rpm without additional heating, thereby producing the superhydrophobic sheet which is peeled off from the solid substrate,
wherein the superhydrophobic sheet has a total thickness of about 10 μm to about 340 μm.