## 2 Experimental Section  
### General  
All solvents and reagents, unless otherwise indicated, were purchased from commercial sources and used directly as supplied. Tyvek(r) polyethylene nonwoven fabric was obtained from E. I. du Pont de Nemours and Company, Wilmington, DE, and Kolon(r) gsm70 spun-bonded polyester fabric was obtained from Korea Vilene, Inc. 1H and 19F NMR spectra were recorded on a Bruker DRX 400 or 500 spectrometer. Chemical shifts are reported in ppm relative to an internal reference (CDCl\({}_{3}\), CFCl\({}_{3}\) or TMS). All melting points reported are uncorrected. Contact angle (CA) measurements for both water and hexadecane on a surface were performed according to procedures in the manufacturer's manual using a Rame-Hart Standard Automated Goniometer Model 200 employing DROP image standard software and equipped with an automated dispensing system with a 250 \(\mu\)L syringe and an illuminated specimen stage assembly. 2\(H\),2\(H\),3\(H\),3_H_-perfluorononyl chloride, 2\(H\),2\(H\),3\(H\),3_H_-perfluoroheptanoyl chloride, 1\(H\),1\(H\),2\(H\),2_H_-perfluorooctyl isocyanate and 1\(H\),1\(H\),2\(H\),2_H_-perfluorohexyl isocyanate were synthesized from the corresponding perfluoroalkylethyl iodides [34]. Synthesis of 2\(h\),2\(h\),3\(h\),3_h_-Perfluorononyl Chloride and 1\(h\),1\(h\),2\(h\),2_H_-Perfluorooctyl Isocyanate  
A four-neck reactor fitted with a stirrer, thermocouple, nitrogen purge, addition funnel and jacketed condenser was purged with nitrogen and charged with magnesium turnings (4.86 g, 202.5 mmol) and anhydrous ether (300 mL). To this suspension was slowly added a solution of 1\(H\),1\(H\),2\(H\),2_H_-perfluorooctyl iodide (94.8 g, 200 mmol) in ether (100 mL) over a 2 h period. After the addition of about 10 mL of iodide, the mixture was heated to 35 \({}^{\circ}\)C, and when the reaction was initiated the rest of the iodide was added, keeping the temperature below 35 \({}^{\circ}\)C. The mixture was stirred for 2 h at room temperature (RT) and cooled to 5-10 \({}^{\circ}\)C. Excess dry ice (\(\sim\)15 g) was added in small portions with  
Figure 2: General structure of partially fluorinated amide and urea-amide derivatives described in this study. constant stirring. After 15 min, the mixture was quenched with H\({}_{2}\)SO\({}_{4}\) (25%) and the ether phase was separated. The aqueous phase was extracted with ether (2 \(\times\) 100 mL). Combined ether phases were washed with NaOH solution (25%, 3 \(\times\) 75 mL). The combined alkaline phases were heated at 100 \({}^{\circ}\)C for 10 min and neutralized using H\({}_{2}\)SO\({}_{4}\) (50%) after cooling to ice temperature. The precipitate formed was filtered and washed with water to obtain 2\(H\),2\(H\),3\(H\),3_H_-perfluorononoic acid as a white crystalline solid (56.5 g, 14.1 mmol, 72%). mp. 61-63 \({}^{\circ}\)C.  
The 2\(H\),2\(H\),3\(H\),3_H_-perfluorononoic acid (44.4 g, 113.2 mmol) was heated with PCI\({}_{5}\) (35.4 g, 169.8 mmol) at 110 \({}^{\circ}\)C for 3 h and the resulting mixture fractionally distilled to obtain 2\(H\),2\(H\),3\(H\),3_H_-perfluorononoyl chloride as a colorless liquid (44.5 g, 107.5 mmol, 95%). bp. 129 \({}^{\circ}\)C _@_ 85 mm Hg. A 3-necked flask fitted with a stirrer, an addition funnel and a condenser with N\({}_{2}\) purge was charged with freshly distilled 2\(H\),2\(H\),3\(H\),3_H_-perfluorononoyl chloride (16.26 g, 39.6 mmol). Trimethylsilyl azide (TMSN\({}_{3}\), 4.57 g, 39.61 g) was added dropwise via the addition funnel, keeping the temperature about 5-10 \({}^{\circ}\)C. The mixture was then stirred at 10 \({}^{\circ}\)C for 30 min and heated at 75 \({}^{\circ}\)C for 1.5 h. After the reaction was complete (GC analysis), trimethylsilyl chloride was distilled off at atmospheric pressure and then the product was fractionally distilled under vacuum to produce 1\(H\),1\(H\),2\(H\),2_H_-perfluorooctyl isocyanate as a colorless liquid (11.9 g, 30.6 mmol, 77%) bp.100-103 \({}^{\circ}\)C _@_ 30 mm Hg.