Table 2.
Physicochemical characteristics of selected poloxamer block copolymers.
Copolymer | Molecular massa | Average no. EO units (x)b | Average no. PO units (y)c | Hydrophilic-lipophilic balance (HLB)c | Critical micelle concentration (CMC), % w/vd |
---|---|---|---|---|---|
Pluronic L61 | 2000 | 4.6 | 31.0 | 3 | 0.02 |
Pluronic P85 | 4600 | 52.3 | 39.7 | 16 | 0.03 |
Pluronic F127 | 12600 | 200 | 65.2 | 22 | 0.004 |
Pluronic F68 | 8400 | 153 | 29.0 | 29 | 0.4 |
Average molecular weights provided by the manufacturer (BASF, Wyandotte, Michigan)
The average number of ethylene oxide (EO) and propylene oxide (PO) units
Hydrophilic-lipophilic balance (HLB) values of the copolymers and the cloud points were determined by manufacturer (BASF, Wyandotte, Michigan)
CMC values were determined previously using pyrene probe [48].