The Effect Of Alkyl Aryl Sulfonate Structure On The Phase Behavior

In this paper,seven kinds of alkyl aryl sulfonates(AAS)which have definite structure were finely synthesized from methylbenzene(or dimethylbenzene),decanoyl(or undecanoyl,dodecanoyl,tridecanoyl)chloride and(-bromoalkane(or heptyl bromide),The content of surfactant in the products were all more than 95.%.The complex system of the seven kinds of different structre alkyl aryl sulfonate(synthesized in the laboratory)/different alchol/n-decane/Nacl water microemulsions were investigated by Winsor phase diagram.The influences of molecular structure,temperature and alcohol were respectively discussed.The results show that as the the number of long alkyl carbon atoms in alkyl aryl sulfonate molecule increase,the value of S1,?S,S*decrease,the value of VM*,?*increase;as the aromatic rings shift from the edge to the middle of the long carbonic chains,the value of S1,S2,?S,S*decrease,the value of VM*??*a increase;With the increase of temperature,the value of S1,S2,?S,S*increase,the value of VM*,?*decrease,and at 25?,the Middle Phase Microemulsion can not be formed;The increase of carbon atom number of the alcohol cause the value of S1,S2,AS,S*decrease,the value of VM*,?*increase;We use dilution method to study the effect of AAS structure,temperature,short chain alcohol,water content and inorganic salt content on thermodynamic properties of microemulsion formed by these AAS.The results show that the increase of the number of long alkyl carbon atoms in alkyl aryl sulfonate molecule,the ?G0o?1 of the microemulsion systems decrease,the formation ability of the microemulsion increase,the ?S0o?i decrease also,the ?S0o?i and carbon atom number of alkyl chain are in linear relationship,the ?H0o ?i don't change.As the aromatic rings shift from the edge to the middle of the long carbonic chains,the ?H0o ?i of the microemulsion systems decrease,the formation ability of the microemulsion increase.the ?H0o ?i and ?H0o ?i decrease.With the increase of temperature,?H0o ?i of the microemulsion systems increase,the formation ability of the microemulsion decrease,The increase of carbon atom number of the alcohol cause ?H0o ?idecrease,the formation ability of the microemulsion increase,the value of ?H0o ?i and carbon atom number of the alcohol are in linear relationship.As the water content increase,?H0o ?i increase,the formation ability of the microemulsion decrease,the value of ?H0o ?i the volume of water are in linear relationship.The increase of salt concerLration cause1?H0o ?idecrease,the formation ability of the microemulsion increase.