The application of polycarboxylic acid as a fluid loss additive for cement(i.e.,a substance specifically designed to lower the volume of filtrate that passes through the cement)can prolong the thickening time of cemen...The application of polycarboxylic acid as a fluid loss additive for cement(i.e.,a substance specifically designed to lower the volume of filtrate that passes through the cement)can prolong the thickening time of cement slurries.Given the lack of data about the effects of carboxylic acid monomers as possible components for the additives traditionally used for oil-well cement,in this study different cases are experimentally investigated considering different types of these substances,concentrations,temperatures,and magnesium ion contamination.The results demonstrate that itaconic acid has a strong retarding side effect,while maleic and acrylic acids have similar influences on the thickening time of the cement slurry.The rheological properties of the cement slurry tend to deteriorate when the carboxylic acid monomer content in the fluid loss additive is increased to 40%.If the temperature exceeds 80°C,there is a significant decrease in the related impact on the thickening duration.With an increase in the intrusion of magnesium ions to>0.5%,both the rheological properties of the cement slurry and the thickening time are affected in a negative way.展开更多
Complex of rare earth with carboxylic acid was prepared by precipitation and direct method. It was copolymerized with such monomers as acrylic acid and other ones to synthesize ionomer of rare earth and organic polyme...Complex of rare earth with carboxylic acid was prepared by precipitation and direct method. It was copolymerized with such monomers as acrylic acid and other ones to synthesize ionomer of rare earth and organic polymer with different rare earth contents. Its glass-transition temperature and heat stability were analyzed by TG and DTA. Infra-red detector was used to show its structure. The effect of rare earth complex prepared by different methods on copolymerization and properties of copolymers was also discussed.展开更多
Copolymer of acrylic acid grafted polyethylene is used as membrane of ion exchanger.Its preparation and application were reported in many articles. However, its characterization was reported by only a few. In the pres...Copolymer of acrylic acid grafted polyethylene is used as membrane of ion exchanger.Its preparation and application were reported in many articles. However, its characterization was reported by only a few. In the present work, the copolymer is studied with X-ray photoelectron spectroscopy （XPS）. It is shown from the shift of the carboxyl group position in the spectra of C1s level that there are hydrogen-bonds in the copolymer. The grafting degree was characterized by the ratio of different carbon peak areas in the C1s spectra. Therefore, this method is very useful for the qualitative and quantitative展开更多
文摘The application of polycarboxylic acid as a fluid loss additive for cement(i.e.,a substance specifically designed to lower the volume of filtrate that passes through the cement)can prolong the thickening time of cement slurries.Given the lack of data about the effects of carboxylic acid monomers as possible components for the additives traditionally used for oil-well cement,in this study different cases are experimentally investigated considering different types of these substances,concentrations,temperatures,and magnesium ion contamination.The results demonstrate that itaconic acid has a strong retarding side effect,while maleic and acrylic acids have similar influences on the thickening time of the cement slurry.The rheological properties of the cement slurry tend to deteriorate when the carboxylic acid monomer content in the fluid loss additive is increased to 40%.If the temperature exceeds 80°C,there is a significant decrease in the related impact on the thickening duration.With an increase in the intrusion of magnesium ions to>0.5%,both the rheological properties of the cement slurry and the thickening time are affected in a negative way.
文摘Complex of rare earth with carboxylic acid was prepared by precipitation and direct method. It was copolymerized with such monomers as acrylic acid and other ones to synthesize ionomer of rare earth and organic polymer with different rare earth contents. Its glass-transition temperature and heat stability were analyzed by TG and DTA. Infra-red detector was used to show its structure. The effect of rare earth complex prepared by different methods on copolymerization and properties of copolymers was also discussed.
文摘Copolymer of acrylic acid grafted polyethylene is used as membrane of ion exchanger.Its preparation and application were reported in many articles. However, its characterization was reported by only a few. In the present work, the copolymer is studied with X-ray photoelectron spectroscopy （XPS）. It is shown from the shift of the carboxyl group position in the spectra of C1s level that there are hydrogen-bonds in the copolymer. The grafting degree was characterized by the ratio of different carbon peak areas in the C1s spectra. Therefore, this method is very useful for the qualitative and quantitative
