segments decreases, which results in an increase of the fractional area occupied by the PEO

segments and, as a consequence, in a more pronounced pseudoplateau.



 E o5 H 3.0
 Z t = 10 his





 E 31IlilII

 U52 40000-~- 800 100
 Mea Moecla Area(A
 Figure~ 5-7 ufc rsueM Aiohrso he(B0--E363Sa lc ooye
 an ~of h orsodn yrslltd(BS(~))bPO3Sa lc ooye
 before~~~P an afe cos-ikig





Fgreorded forfc Pesr-M otherm hydoslylte (PB(SiO0)3-b-PEO32)3 Star block copolymerafediern




reaction times (pH = 3.0) as shown in Figure 5-18A. Fresh monolayers were spread for every

isotherm and the barrier compression speed was set to 100 mm/min to prevent additional cross-

linking during compression. As the reaction proceeds, the isotherms shift toward the low MMA

region because of a more compact cross-linked material, with the PEO pseudoplateau becoming

more and more pronounced because of the PEO fractional area influence mentioned above. The

reappearance of the PEO pseudoplateau is better shown by plotting monolayer compressibility

versus MMA for different reaction times as shown in Figure 5-18B, where the maximum in