Synthesis And Solution Properties Of Microblock Amphiphilic Polymers With High Content Of Surfmer Units

Amphipilic polymers have become an important research field due to their unique physicochemical properties in solution. In this thesis, according to the development of research about the amphiphilic polymers applied in enhanced oil recovery, three kinds of novel microblock amphiphilic polymers with high content of surfmer units were designed and synthesized. These novel microblock polymers were synthesized by 2-(acrylamido)-2-methyl propanesulfonic acid sodium (NaAMPS) and surfmers in aqueous solution through free radical random polymerization. The solution properties and aggregation behaviors of the polymers were also explored. The research results show that these novel microblock polymers both have the characteristics of associative polymers and the surfactant activities of polymeric surfactant. The research results are shown in detail as follows.1. Copolymer NaAMPS/AA-TX-100 series bearing high nonionic surfmer units were synthesized and characterized by IR and 1H-NMR. The cac values of copolymer NaAMPS/ AA-TX-100 series are increased with the decrease of surfmer units in the fluorescence spectroscopy test and concentration vs viscosity test, as the introduced surfmer units AA-TX-100 along polymer chain can lead to strong intermolecular hydrophobic association in water. Copolymer NaAMPS/AA-TX-100 series show better salts tolerance than poly-(2-acrylamido-2-methyl propanesulfonic acid sodium) (P(NaAMPS)). The shearing resistance test shows that copolymers solutions have shear thicken ability at low shear rate, which may be due to the susceptible intramolecular association formed by copolymers with high content hydrophobic groups (more than 1mol%). Copolymers can reduce the interfacial tension between n-heptane/water and the IFT values are around at 100mN·m-1 level and have good ability to form emulsions with good stability in water. The environmental scanning electron microscope tests show that copolymer NaAMPS/AA-TX-100 series can form tight networks than P(NaAMPS) that confirms the characteristics of associative polymers and the transmission electron microscope show that copolymer NaAMPS/AA-TX-100 series can form spherical micelles that indicate the properties of polymeric surfactant. The viscosity reducing effect for heavy oil was investigated and the results of copolymer NaAMPS/AA-TX-100 series are unsatisfied, which is due to the W/O emulsion type that can cause high viscosity of emulsion.2. Copolymer NaAMPS/C18DMAAB series bearing high cationic surfmer units (more than 2mol%) were synthesized and characterized by IR and’H-NMR. The fluorescence spectroscopy test and concentration vs viscosity test both show that the cac values of copolymer NaAMPS/C18DMAAB series are decreased with increment of surfmer units. Copolymer NaAMPS/C18DMAAB series show good salts tolerance and thermal stability at high temperature. The shearing resistance test shows that copolymers solutions have shearing thickening ability at low shear rate, which may be due to the susceptible intramolecular association formed by copolymers with high content hydrophobic groups. Copolymers can reduce the interfacial tension between n-heptane/water and the IFT values are at 100mN·m-1. The emulsions formed by copolymers have good ability to form emulsions with good stability in water and brine. The environmental scanning electron microscope tests show that copolymer NaAMPS/C18DMAAB series can form tight networks than P(NaAMPS) that confirms the characteristics of associative polymers and the transmission electron microscope show that copolymer NaAMPS/C18DMAAB series can form spherical micelles that indicate the properties of polymeric surfactant. The viscosity reducing effect for heavy oil was investigated and the results of copolymer NaAMPS/C18DMAAB series are good. The viscosity reducing rate can be both achieved above 95% in water and brine, when the concentration of copolymers was 5000mg/L. AC18-2.5 has better ability to reduce the viscosity of heavy oil than the other two copolymers due to the highest molecular weight it owned in copolymer NaAMPS/C18DMAAB series.3. A novel zwitterionic surfmer was designed and synthesized by acrylonitrile, C18DMAAB and oleum. The structure of this zwitterionic surfmer was characterized and confirmed by IR,1H-NMR, 13C-NMR and MS. Copolymer NaAMPS/AMSC18DMAB series bearing high zwitterionic surfmer units (more than 2mol%) were synthesized and characterized by 1H-NMR and GPC. The fluorescence spectroscopy test and concentration vs viscosity test both show that the cac values of copolymer NaAMPS/AMSC18DMAB series are decreased with increment of surfmer units. However, copolymer with high content surfmer units could just achieve a low viscosity that may be due to their low molecular weight. Copolymer NaAMPS/AMSC18DMAB series show excellent salts tolerance in high salinity brine and thermal stability at high temperature. The shearing resistance test shows that copolymers solutions have shearing thickening ability at low shear rate, which may be due to the susceptible intramolecular association formed by copolymers with high content hydrophobic groups. Copolymers can reduce the interfacial tension between n-heptane/water and the IFT values are at 100mN·m-1. The emulsions formed by copolymers have good ability to form emulsions with good stability in water and high salinity brine. The environmental scanning electron microscope tests show that copolymer NaAMPS/AMSC18DMAB series can form tighter networks than P(NaAMPS) that confirms the characteristics of associative polymers and the transmission electron microscope show that copolymer NaAMPS/AMSC18DMAB series can form spherical micelles that indicate the properties of polymeric surfactant. The viscosity reducing effect for heavy oil was investigated and the results of copolymer NaAMPS/AMSC18DMAB series are good. The viscosity reducing rate can be both achieved above 95% in water and high salinity brine, when the concentration of copolymers was 5000mg/L. These copolymers all have good abilities to reduce the viscosity of heavy oil due to the high and closed molecular weights they owned.