. First compression
cI First expansion
o Second compression
* Second expansion


* PEO2000 2
a PEO core pHI=5.5 20


40 60
ylene
(M)"


 20 -
 ~-oPEO core pH=1 3 15 -
 ~4 -s- PEO2670 10E~l
 ~15 -

 E 0 20
 10 Area per eth
 ~t oxide unit






 0 500 1000 1500 2000
 MMA (AZ2)

Figure 4-3. Isotherms of the PEO homopolymers. (Inset) Same
 respect to the number of ethylene oxide units.


I


 2500 3000



isotherms normalized with


300


600 900
 MMA (AZ2)


1200


1500


Figure 4-4. Compression-expansion hysteresis plot of the PEO core (target pressure = 2 mN/m).