Heat-resistant Foam Research Articles

Heat-Resistant CO2 Foam for Promoting Carbon Capture and Enhanced Oil Recovery

Investigation of methods to effectively block the high-permeability channel and displace the residual oil in the small pores in the old oilfields is an urgent research hotspot. The heat-resistant carbon dioxide (CO2) foam with high viscoelasticity and low interfacial tension, which is suitable for improving the oil recovery of old oilfields, and at the same time aids in carbon sequestration. In this study, a suitable heat-resistant foaming agent was selected by considering the temperature resistance, plugging, and profile control as the evaluation indicators, and the heat-resistant CO2 foam was prepared. Then, the two-dimensional (2D) plate model experiment was designed to verify the feasibility of the heat-resistant CO2 foam profile control process in order to solve the problems of small sweep range and uneven sweep degree in the reservoir. The results show that the selected foaming agent (RSB-IV) still maintained a foaming volume of 375 ml at 300°C, and the interfacial tension was only 0.008 mNm−1. The prepared heat-resistant CO2 foam exhibited the best profile control effect when the gas and liquid mixed injection, the gas-liquid ratio was 1:1, and the injection volume was 4.5–5.5 PV. In the 2D plate experiment, heat-resistant CO2 foam flooding promoted the recovery of the remaining oil in the matrix, and the oil recovery was increased to 61.01%. Furthermore, by designing the CO2 gas cap, it was verified that when the volume of the gas cap was large (above 1.5 PV), the injection of the CO2 gas cap could not only effectively improve the recovery rate, but also achieve effective CO2 capture.

Heat-Resistant Foam Concrete on the Basis of Two-Component Binder

The composition of dry mix on the basis of two-component cementing agent (aluminous cement and clay of the “Kustikha” field), mineral additives (a metakaolin, the RSAM sulfoaluminate modifier, waste of basalt fiber), Ufapore foamer and the accelerating and plasticizing “Citrate-T” additive is developed. When mixing “Citrate-T” additive with water at Water/Solid = 0.45–0.70, the subsequent mechanical binder and hardening of a foam mass heat-resistant foam concretes with a density of 300–650 kg/m3 are formed (depending on Water/Solid value). Foam concretes have strength on compression of 0.2–2.5 MPa before warming up when their initial strength depends on processes of hydration curing of aluminous cement that provides fixation of their porous structure. After annealing at 1000 °C foam concretes have final strength of 0.3–3.2 MPa due to processes of solid-phase agglomeration of clay with other components of dry mix at their heating. Foam concretes after annealing unlike foam concretes on the basis of a Portland cement and aluminous cement have big strength. Introduction of the accelerating and plasticizing “Citrate-T” additive into composition of the dry mix leads to an increase of rheological properties in expanded foam mass and time reduction of its drying and curing. It has been established that an essential role is played by the relation Water/Solid: at increase in the relation Water/Solid (with 0.45 to 0.70) occurs increase in volume of foam mass after a mechanical binder, and also heterogeneity of pores and their sizes increases that leads to reduction of density of foam concretes and strength on compression.

The price of fire safety

Straight out of college, Ted Schaefer’s first assignment at 3M Canada was to provide technical support and formulate firefighting foams. It was 1980, and 3M was the dominant producer of fluorosurfactant-containing foams used to quell hydrocarbon fires after aircraft crash landings and to put out fires at oil refineries, chemical plants, and storage-tank facilities. From the 1970s through the 1990s, 3M’s Light Water fire suppressant—and other fluorosurfactant-based firefighting foams like it—were the “highest performing” foams available, recalls Schaefer, who earned a degree in chemistry from the University of Waterloo. The foams seemed to have few, if any, drawbacks. A concentrated formula, diluted with water, forms a heat-resistant foam blanket that rapidly cools and smothers most hydrocarbon-fueled fires. The fluorine content helps create a low-surface-tension film that rapidly spreads across the surface of a flammable liquid. A foam’s quick action in a fire can mean the difference between life and death.

Nondestructive examination of polymethacrylimide composite structures with terahertz time-domain spectroscopy

THz reflective time domain spectroscopy (THz-RTDS) has been considered as an effective method to detect hidden objects with potential for supplementing other NDE technologies for foam composite adhesive structure debonding defects. PMI (Polymethacrylimide) is a heat-resistant foam material, with the highest strength and stiffness to weight ratio. It is widely used in various parts of airplanes, especially the wing leading edge and rudder, landing gear doors, wing-body/wingtip fairings and so on. We analyzed the features of adhesive debonding defect based mainly on the variation of the time-domain wave form and compared with the inclusion defect. The quantification of degrees of adhesive debonding can be readily achieved with THz-RTDS images based on the delay of the wave front and the main reflection time-domain waveforms. Typical accuracy of about 100 μm was achieved.

ПЕНООБРАЗУЮЩИЙ СОСТАВ ТЕРМОСТОЙКОЙ ПЕНЫ НА ОСНОВЕ ХМЕЛЯ

ПЕНООБРАЗУЮЩИЙ СОСТАВ ТЕРМОСТОЙКОЙ ПЕНЫ НА ОСНОВЕ ХМЕЛЯ

Study of Rigid Cross-Linked PVC Foams with Heat Resistance

Three heat resistant cross-linked PVC foam plastics were prepared and their performances were compared with universal cross-linked PVC structural foam. The results show that these three heat resistant foams have higher glass transition temperatures (close to 100 °C) than universal structural foam (83.2 °C). Compared with the universal structural foam, the three heat resistant foams show much higher decomposition temperature and better chemical stability due to the crosslinking of PVC macromolecular chains. The heat distortion temperature (HDT) values of the three heat resistant foam plastics are just a little higher than that of universal structural foam. The three heat resistant foam plastics have good dimensional stability at 140 °C, and when used as core material can closely adhere to the face plates in medium temperature curing processes. Compared with universal structural foam, the three heat resistant foam plastics have slightly better mechanical properties.

Preparation of New Polyimides by Diels–Alder Reaction of Various Bis-pyrones and Bismaleimide of Methylenedianiline (BMI-MDA)

The synthesis and characterization of novel polyimides obtained by Diels–Alder reaction of bis-pyrones and bismaleimides are studied. The present cycloadducts contain CO2 bridges, which can be eliminated by subsequent heat treatment, thereby generating stable aromatic systems. The CO2 released acts as blowing agent, leading to porous structures that are in high demand in the manufacture of heat-resistant foams. However, in this type of material, one should always seek a good compromise between the temperatures of polymerization and decarboxylation of early degradation. All polymers are analyzed with 13C-, solid-state NMR and coupling ATG/IR. The studies of their thermal behaviour, examined by thermogravimetric analysis and differential scanning calorimetric analysis, show that these polyimides have a good thermal stability and are mainly amorphous.

Sekisui Irradiates Acrylonitrile to Produce Strong Heat-Resistant Foam

Sekisui Irradiates Acrylonitrile to Produce Strong Heat-Resistant Foam