ABSTRACT
VariationsofthenormalizedratioQ~(O)/Q~areillustratedinFig.10asa functionoftheweightratio¢oH.Astraightlinecanbedrawnthroughexperimental pointswithaslopeequalto-4.7.Thisresultisanalyzedinthefollowingway.Asa consequenceoftheuniformoccupancyofthesilicasurface,thenumberoffree silanolgroupsreplacedwithhydroxylatedendsofshortchainsis
4MoH (36)
whereMoHisthemolarweightofanhydroxylgroup;thenumberofchainswhich cannotbeadsorbedisthusequaltonsioHI-INonaverageandthenormalized amountofadsorbedlongchainsisexpressedas
Q~(O)_I_¢oH0.05.•/v'lVim.JMn Q~- 4MoHQ~(37)
Thenumericalvalueoftheslopeis-4.9forM 11=115,000gjmol,inreasonable agreementwiththeexperimentalvalue.
