Synthesis And Properties Of Nonylcyclohexanol Polyoxyethylene Ether

Nonylphenol polyoxyethylene ether?NPEO_n?with excellent properties of wettability,emulsification,solubilization and detergency,was used to be the second-largest nonionic surfactant in the world,and was widely used in various fields of industry and agriculture.However,NPEO_n has already been banned or restricted to use worldwidely due to its poor biodegradability,high accumulation in the environment,and high biotoxicity,which makes the research of its green alternatives an urgent problem to be solved in nonionic surfactants and related application fields.Several alternatives have been developed to alternate NPEO_n in partial performances,however,few researches are focused on the overall alternation of NPEO_n in terms of the structure-property relationship.Nonylcyclohexanol polyoxyethylene ether?NCEO_n?which has the similar molecular structure to NPEO_n was designed and synthesized by replacing phenolic oxide block with cyclohexanol block from the perspective of structure,and the structure-property relationships were also investigated.In order to evaluate whether the NCEO_n that was designed and synthesized in this thesis could be the green alternative to NPEO_n,the primary biodegradability and the properties of NCEO_n especially the emulsifing capacity of silicone oil were investigated by comparing with those of NPEO_n.An NP HPLC program was proposed for rapidly determining the residual NC in NCEO_n by combining an Inertsil NH₂ column,a refractive index detector with the eluent of ethyl acetate on the basis of five preliminary experiments of NP HPLC and reversed phase HPLC.The optimum results were obtained with a recovery of 91.77%?107.6%,a relative standard deviation?RSD?of 1.59%?4.46%and a limit of detection?LOD?9.8?g·mL^-1 were got.Therefore,the demand of the quick determination of NC residue amount in NCEO_n synthesized in this thesis was well met by this program.Fourty one catalysts in eight series of metal hydroxide,metal alkoxide,metal oxide,metal hydride,fatty acid salt,metal hydride,Lewis acid and Lewis acid ionic liquid were screened with catalytic activity,NC residual and product selectivity as the main indicators,and NaH was selected out as a sutable catalyst for the synthesis of NCEO_n.NCEO₇ was obtained with the catalytic activity of 0.519 g EO·g^-1 Cat·min^-1,the NC conversion of 99.6%,PEG content of 7.2%and polydispersity index?PDI?of 85%under the optimized reaction conditions of catalyst amount of 0.5 wt.%of NC,reaction temperature of 120?and EO pressure of 0.40 MPa,which indicates that the NCEO_n products have good qualities with a low NC residue,a low PEG content and a narrow distribution.A series of NCEO_n?n=5,7,9,11?were synthesized with NaH as catalyst,and the structures of these products were characterized by Fourier transform infrared spectroscopy?FT-IR?,electrospray ionization mass spectrometry?ESI-MS?and nuclear magnetic resonance spectroscopy?¹H-NMR?.The structure-property relationship was invrestegated based on the primary biodegradability of NCEO₇,surface activity and property of NCEO_n,then the molecular configuration of NCEO₁ were optimized.The results show that the primary biodegradation of NCEO₇ is almost complete based on the seven-day activated sludge assessment,which is obviously superior to that of NPEO_n.The results of structure-property relationship show that the cloud point?CP?,the critical micelle concentration?cmc?,the saturated adsorption area?a_m?and the foamability were increased and the saturated adsorption amount??38?_m?and the emulsifing capability of silicone oil were decreased with the increase of average EO adduct number?n?of NCEO_n.The wettability and emulsification were increased first and then decreased with the increase of n,and NCEO₉ was selected as the optimum one.The surface activity property of NCEO₉ is close to or even better than that of NPEO₉,and NCEO₉ is also better than that of NPEO₉ in terms of emulsification of silicone oil and detergency of carbon-black swatches.NCEO_n has better low foam property than that of NPEO₉,while the wettability is slightly less than that of NPEO₉.All the excellent properties of NCEO_n should be attributed to the similar structure between NCEO_n and NPEO_n.All in all,NCEO_n could be a green alternative for NPEO_n thanks to the results of synthesis,primary biodegradation and properties including emulsification of silicone oil.