Synthesis And Properties Of Gemini Phosphates

Gemini surfactants possess two hydrophilic headgroup and two hydrophobic tails separated by a spacer chain.They had low critical micelle concentration values and high surface active.They were named of a new generation of surfactants,In this text,an explormance study had been instigated into the synthesis and performance of anionic gemini surfactants the hydrophilic headgroup was phosphate group and got concisions. The preparation process concluded three steps.The first step,the glycidyl ether was prepared by reaction of intiator long-chain alkyl alcohol with epichlorohydrin in the presence of phase transfer catalyst.Purification of reaction mixture was performed by reduced pressure and theproductivity was 70% above.Analyzing the IR and 1HNMR of aim product,thestructure was confirmed.The second step,the digomeric glycol-intermediate product of Gemini.surfactant was prepared by opening ring reaction of glycide ether in the presence of potassium as catalyst.The feedstock in the synthetic process was different from the report of foreign literature,so two process were different.The influences of the ratio of reactants,amount of catalyst,reaction temperature and reaction time were studied and technological conditions were optimized by orthogonal experiments.Analyzing its IR and 'HNMR,the structure wasconfirmed.Based on the optium process conditions series of digomeric glycol such as dioctyl digomericglycol,didecatyl digomericglycol and didodecyl digomeric glycol were synthesized,and the highest productivity could reachto 70% above.The third step,we composed the surfactant of two phosphate group and two long-chain alkyl groups with the material of digomericglycol and phosphatizing agent phosphoric anhydride by phosphatation and neutralization.In phosphatation,some factors which affect the productivity biggerly such as the input material ratio,the temperature and time of the reaction were discussed.The better technologicalcondition was got. In that technological conditions series of the Gemini surfactants of two phosphate groups and two long-chain alkyl groups which were octyl,decatyl and dodecyl were synthesized.We knowledge their structure information by analyzing their IR and 'HNMR.The difference of process condition between using phosphoric anhydride and documents' polyphosphoric acid were compared.We found that using phosphoric anhydride as phosphatizing agent would reduce reaction time,and in the absence of solvent ,the propertied of products were better.At last,some properties of all products were tested and the connection between structure and properties were discussed.The experiments result indicated that PGKs have lower CMC values,better wettability and better emulsifier.At the same time ,they also had better anti-static property .