Hydrophobically associating water-soluble polymers (HPAP) have been synthesized from acrylamide(AM), acrylate (AA), 2-acrylamido-2-methyl propane sulfonic acid (AMPS) and hydrophobic monomer (AP) in aqueous solution...Hydrophobically associating water-soluble polymers (HPAP) have been synthesized from acrylamide(AM), acrylate (AA), 2-acrylamido-2-methyl propane sulfonic acid (AMPS) and hydrophobic monomer (AP) in aqueous solution by radical polymerization. New polymer drilling fluids are made up of HPAP, which is used as viscosifiers and encapsulation agents. Properties of this system are reported in this paper. Results indicate that this system has a high value of yield point to plastic viscosity (YP/PV≥0.7), high viscosity at a low-shear rate (LSRV≥30000mPa·s), excellent shear thinning behavior, good solid-carrying behavior, resistance to shear, good thermal stability (as high as 140℃) and salt resistance. The system has excellent behavior in high-density solution of NaCl and in calcium and magnesium rich saline solutions. Hence, HPAP also can be used in saltwater polymer drilling fluids.展开更多
In this article, the synthesis and characterization of a novel fluoromonomer and its copolymer with acrylamide is reported. 2-perfluoroamyl-4-hydroxylquinoline 2 was synthesized from ethyl 2, 2-dihydroperfluoroheptano...In this article, the synthesis and characterization of a novel fluoromonomer and its copolymer with acrylamide is reported. 2-perfluoroamyl-4-hydroxylquinoline 2 was synthesized from ethyl 2, 2-dihydroperfluoroheptanoate in high yields. The monomer 4 was then synthesized from 2 in two steps readily in high yields. Synthesis and characterization of copolymers of acrylamide (AM) and the fluoromonomer were investigated. The composition and intrinsic viscosity of these copolymers were studied. It was found that the rheological properties of aqueous solutions of polyacrylamide were modified significantly when a small proportion of the fluoromonomer 4 was incorporated on investigating the viscosity-concentration profiles, pseudoplasticity of these solutions and the effect of the presence of surfactant. These results could be explained by the hydrophobic association of the fluorocarbon segments in the aqueous solutions of these copolymers.展开更多
Acrylamide/2-acrylamido alkane sulfonic acid hydrophobic associating copolymers were synthesized by micellar copolymerization. Effects of hydrophobe content, polymer concentration, salinity and surfactant on rheologic...Acrylamide/2-acrylamido alkane sulfonic acid hydrophobic associating copolymers were synthesized by micellar copolymerization. Effects of hydrophobe content, polymer concentration, salinity and surfactant on rheological behavior of copolymers were investigated and the conformation of polymers in solution was studied by means of environmental scanning electronic microscopy and dynamic light scattering. The experimental results showed that in the dilute regime the hydrophobic parts could interact intramolecularly, while in the regime where the polymer concentration was higher than the critical association concentration, intermolecular hydrophobic association became predominant. Within the limit of the solubility, the critical association concentration of the polymer decreased with the increase of the salinity. The experimental results of the solution conformation indicated the presence of the three-dimensional network structure in deionized water and the size of the mesh in the network varied with the polymer concentration. In NaCl solution, above the critical association concentration, an increase in polymer concentration enhanced the intermolecular association and also enlarged the hydrodynamic radius. It would result in the improvement of the thickening power of polymers.展开更多
A temperature-resistant, salt-tolerant polyacrylamide, hydrophobically associating polymer (HAP), was synthesized in the State Key Laboratory of Heavy Oil Processing. The rheological behavior of HAP solution was inv...A temperature-resistant, salt-tolerant polyacrylamide, hydrophobically associating polymer (HAP), was synthesized in the State Key Laboratory of Heavy Oil Processing. The rheological behavior of HAP solution was investigated by means of flow experiments in porous media and by using a HAAKE RS600 rheometer. The results of Nuclepore membrane filtration showed that filtration time increased sharply when the critical association concentration was reached. Shear rate had a greater impact on viscosity and shear stress with increasing HAP concentration. The HAP solution with a concentration of 100 mg/L (salinity 32,868 mg/L) exhibited negative thixotropy. However, at the same salinity the HAP solution showed thixotropy and its viscosity became greater when the polymer concentration increased to 1,500 mg/L. The flow experiments in cemented core samples indicated that the resistance factor and residual resistance factor of the HAP solution were 31.8 and 12 when polymer concentration and salinity were 1,500 mg/L, 32,868 mg/L at 85℃ respectively, which is favorable for flooding application. Such factors of partially hydrolyzed polyaerylamide 3530S were merely 3.14 and 1.71, so it could not be applied to polymer flooding in the oilfield with high temperature and high salinity.展开更多
The capability of hydrophobic association polymer(HAPAM) to displace oil is different from that of hydrolyzed polyacrylamide(HPAM) because they have different rheological properties.The viscoelasticity of five polymer...The capability of hydrophobic association polymer(HAPAM) to displace oil is different from that of hydrolyzed polyacrylamide(HPAM) because they have different rheological properties.The viscoelasticity of five polymers was measured using Physica MCR301 rheometer and was compared.The five polymers include three HAPAMs with relative molecular mass of 1 248×104(TypeⅠ),750×104(TypeⅡ),and 571×104(Type Ⅲ) separately and two HPAMs with relative molecular mass of 1 200×104 and 3 800×104 respectively.The experiment results indicate that the viscoelasticity of HAPAM is better than that of HPAM.The storage modulus G' and the loss modulus G″ for HAPAM solutions are also larger than those for HPAM.Comparing the rheological curves of different HAPAM types,it is found that the viscosity of typeⅡ and type Ⅲ is almost same at different shear rates while the viscosity of type I is the lower than that of Types Ⅱ and Ⅲ.The storage modulus G' and the loss modulus G″ for three types of HAPAM were measured in low oscillation frequency range,and the results show that G' is greater than G″ for all three different types of HAPAM,but their loss modulus is almost same,and the G' is in the order of type Ⅱ>type Ⅲ>type I.In addition,the G' and G″ increase with aging time for all three HAPAM solutions were stayed at different days.The viscoelasticity of type Ⅰ reaches the highest value when aging time is 9 d at 45 ℃,but it is 7 d for type Ⅱ and type Ⅲ.The different viscoelasticity properties can be attributed to self-organization supermolecule networks which is formed by hydrophobic association of HAPAM molecular and molecular chain entanglement.展开更多
To determine the template effect of hydrophobically associating copolymers(HACPs) on the morphology of nano/micro structures, six HACPs were synthesized and used as templates to biomimetically synthesize cuprous ox...To determine the template effect of hydrophobically associating copolymers(HACPs) on the morphology of nano/micro structures, six HACPs were synthesized and used as templates to biomimetically synthesize cuprous oxide(Cu2O), an important semiconductor. This experiment showed a clear relationship between the associating state of the HACP molecules and the morphology of the Cu2O particles. Cu2O hollow spheres were preferentially prepared when the HACP molecules were in an intramolecular associating state. Furthermore, a Cu2O hexapod was easily obtained when the HACP molecules were in an intermolecular associating state. The morphologies of the Cu2O crystals prepared in the presence of the HACPs also confirmed this result.展开更多
文摘Hydrophobically associating water-soluble polymers (HPAP) have been synthesized from acrylamide(AM), acrylate (AA), 2-acrylamido-2-methyl propane sulfonic acid (AMPS) and hydrophobic monomer (AP) in aqueous solution by radical polymerization. New polymer drilling fluids are made up of HPAP, which is used as viscosifiers and encapsulation agents. Properties of this system are reported in this paper. Results indicate that this system has a high value of yield point to plastic viscosity (YP/PV≥0.7), high viscosity at a low-shear rate (LSRV≥30000mPa·s), excellent shear thinning behavior, good solid-carrying behavior, resistance to shear, good thermal stability (as high as 140℃) and salt resistance. The system has excellent behavior in high-density solution of NaCl and in calcium and magnesium rich saline solutions. Hence, HPAP also can be used in saltwater polymer drilling fluids.
基金Project supported by National Natural Science Foundation,Grant approval numbers 29472074 and 29632003
文摘In this article, the synthesis and characterization of a novel fluoromonomer and its copolymer with acrylamide is reported. 2-perfluoroamyl-4-hydroxylquinoline 2 was synthesized from ethyl 2, 2-dihydroperfluoroheptanoate in high yields. The monomer 4 was then synthesized from 2 in two steps readily in high yields. Synthesis and characterization of copolymers of acrylamide (AM) and the fluoromonomer were investigated. The composition and intrinsic viscosity of these copolymers were studied. It was found that the rheological properties of aqueous solutions of polyacrylamide were modified significantly when a small proportion of the fluoromonomer 4 was incorporated on investigating the viscosity-concentration profiles, pseudoplasticity of these solutions and the effect of the presence of surfactant. These results could be explained by the hydrophobic association of the fluorocarbon segments in the aqueous solutions of these copolymers.
基金Supported by the State Key Laboratory of Heavy Oil (No. 200013).
文摘Acrylamide/2-acrylamido alkane sulfonic acid hydrophobic associating copolymers were synthesized by micellar copolymerization. Effects of hydrophobe content, polymer concentration, salinity and surfactant on rheological behavior of copolymers were investigated and the conformation of polymers in solution was studied by means of environmental scanning electronic microscopy and dynamic light scattering. The experimental results showed that in the dilute regime the hydrophobic parts could interact intramolecularly, while in the regime where the polymer concentration was higher than the critical association concentration, intermolecular hydrophobic association became predominant. Within the limit of the solubility, the critical association concentration of the polymer decreased with the increase of the salinity. The experimental results of the solution conformation indicated the presence of the three-dimensional network structure in deionized water and the size of the mesh in the network varied with the polymer concentration. In NaCl solution, above the critical association concentration, an increase in polymer concentration enhanced the intermolecular association and also enlarged the hydrodynamic radius. It would result in the improvement of the thickening power of polymers.
文摘A temperature-resistant, salt-tolerant polyacrylamide, hydrophobically associating polymer (HAP), was synthesized in the State Key Laboratory of Heavy Oil Processing. The rheological behavior of HAP solution was investigated by means of flow experiments in porous media and by using a HAAKE RS600 rheometer. The results of Nuclepore membrane filtration showed that filtration time increased sharply when the critical association concentration was reached. Shear rate had a greater impact on viscosity and shear stress with increasing HAP concentration. The HAP solution with a concentration of 100 mg/L (salinity 32,868 mg/L) exhibited negative thixotropy. However, at the same salinity the HAP solution showed thixotropy and its viscosity became greater when the polymer concentration increased to 1,500 mg/L. The flow experiments in cemented core samples indicated that the resistance factor and residual resistance factor of the HAP solution were 31.8 and 12 when polymer concentration and salinity were 1,500 mg/L, 32,868 mg/L at 85℃ respectively, which is favorable for flooding application. Such factors of partially hydrolyzed polyaerylamide 3530S were merely 3.14 and 1.71, so it could not be applied to polymer flooding in the oilfield with high temperature and high salinity.
基金Project(20873181) supported by the National Natural Science Foundation of ChinaProject(2007AA06Z214) supported by the High-tech Research and Development Program of ChinaProject(ts20070704) supported by Taishan Scholars Construction Engineering
文摘The capability of hydrophobic association polymer(HAPAM) to displace oil is different from that of hydrolyzed polyacrylamide(HPAM) because they have different rheological properties.The viscoelasticity of five polymers was measured using Physica MCR301 rheometer and was compared.The five polymers include three HAPAMs with relative molecular mass of 1 248×104(TypeⅠ),750×104(TypeⅡ),and 571×104(Type Ⅲ) separately and two HPAMs with relative molecular mass of 1 200×104 and 3 800×104 respectively.The experiment results indicate that the viscoelasticity of HAPAM is better than that of HPAM.The storage modulus G' and the loss modulus G″ for HAPAM solutions are also larger than those for HPAM.Comparing the rheological curves of different HAPAM types,it is found that the viscosity of typeⅡ and type Ⅲ is almost same at different shear rates while the viscosity of type I is the lower than that of Types Ⅱ and Ⅲ.The storage modulus G' and the loss modulus G″ for three types of HAPAM were measured in low oscillation frequency range,and the results show that G' is greater than G″ for all three different types of HAPAM,but their loss modulus is almost same,and the G' is in the order of type Ⅱ>type Ⅲ>type I.In addition,the G' and G″ increase with aging time for all three HAPAM solutions were stayed at different days.The viscoelasticity of type Ⅰ reaches the highest value when aging time is 9 d at 45 ℃,but it is 7 d for type Ⅱ and type Ⅲ.The different viscoelasticity properties can be attributed to self-organization supermolecule networks which is formed by hydrophobic association of HAPAM molecular and molecular chain entanglement.
基金Supported by the National Natural Science Foundation of China(No. 51102219) and the Fundamental Research Funds for the Central Umversities of China(Nos.201113024, 41404010204).
文摘To determine the template effect of hydrophobically associating copolymers(HACPs) on the morphology of nano/micro structures, six HACPs were synthesized and used as templates to biomimetically synthesize cuprous oxide(Cu2O), an important semiconductor. This experiment showed a clear relationship between the associating state of the HACP molecules and the morphology of the Cu2O particles. Cu2O hollow spheres were preferentially prepared when the HACP molecules were in an intramolecular associating state. Furthermore, a Cu2O hexapod was easily obtained when the HACP molecules were in an intermolecular associating state. The morphologies of the Cu2O crystals prepared in the presence of the HACPs also confirmed this result.