黏度法研究聚丙烯酰胺与聚乙二醇在水中的相互作用

VISCOMETRIC STUDIES ON THE INTERACTION BETWEEN POLYACRYLAMIDE AND POLY(ETHYLENE GLYCOL) IN WATER

采用黏度法研究了聚丙烯酰胺(PAM)与聚乙二醇(PEG)在水中的相互作用,发现当聚合物浓度较高时,PAM与PEG存在疏水作用、氢键以及相互缠结.两者间的相互作用随着聚合物浓度、PEG分子量以及PAM分子量的升高而增大;随着温度的升高,其相互作用先减小后增大;盐、乙醇以及丙烯酰胺的加入使相互作用减弱.

In order to clarify the interaction between the continuous phase and the dispersion phase rich in polyacrylamide（PAM）,the interaction between PAM and PEG in water was studied by viscosity method.In a dilute aqueous solution of PAM,the segments of PAM molecular chains prefer to combine with water molecules through hydrogen bonding.However,the hydrogen bonding between PAM molecular chains increased with increasing concentration of PAM in water.Because the aqueous PEG solution is a poor solvent for PAM,the PAM molecular chains aggregated with each other and formed compact spherical clews.PEG molecular chains were then congregated around the PAM clew through the hydrophobic interaction,and entwisted on the surface of the PAM clew through hydrogen bonding between PAM and PEG.It was found that the interaction was strengthened with increasing the total polymer concentration,and the molecular weight of PEG or PAM.The strength of the interaction between PAM and PEG in water seems to be not changed markedly with rising temperature.The interaction was a little stronger at higher or lower temperatures.Raising the temperature destroyed the hydrogen bonding between PAM and PEG chains at first.However,the hydrogen bonding between PAM chains and water molecules was also reduced while raising the temperature sequentially.Therefore,the hydrophobic interaction between PAM and PEG in water was increased.The addition of ethanol,salt,acrylamide or urea reduced the hydrogen bonding between the PAM and PEG,and therefore the interaction between PAM and PEG in water was weakened whereas the hydrophobic interaction between PAM and PEG was increased.