The transition of polymers into a network of polymers alters per se the water activity.
We have found that polyacrylamide gels cross-linked with bisacrylamide induce a larger macromolecular osmotic pressure than the non cross-linked gels. This means also that in the cross-linked gels hydration water is held more tightly to the polymer, i.e., more work is needed to remove water, than in the non cross-linked gel. Since the chemical nature of the two gels is extremely similar, we propose that the formation of the network alters per se the water activity.
Trombetta
Giorgio
G
Dipartimento di Biochimica e Biologia Molecolare, Università di Ferrara, via Borsari 46, 44100 Ferrara, Italy.
Di Bona
Cristina
C
Grazi
Enrico
E
D020106:Acrylamide / Q000737:chemistry; D000180:Acrylic Resins / Q000737:chemistry; D003432:Cross-Linking Reagents / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D046911:Macromolecular Substances / Q000737:chemistry*; D015233:Models, Statistical; D009997:Osmotic Pressure; D011108:Polymers / Q000737:chemistry*; D011312:Pressure; D014867:Water / Q000737:chemistry*
D000180:Acrylic Resins; D003432:Cross-Linking Reagents; D046911:Macromolecular Substances; D011108:Polymers; C016680:polyacrylamide gels; D014867:Water; D020106:Acrylamide