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Konjac glucomannan (KGM) and partially hydrolyzed polyacrylamide (HPAM) have good application prospects in the field of petroleum fracturing field, but few studies on the rheological properties of KGM and HPAM double polymer gel systems have been reported. Optimal conditions for the high temperature and shear resistant organozirconium crosslinked double polymer gel system for petroleum fracturing were explored through optimization experiments. The thickener contained a mass ratio of 2:1 of KGM to HPAM, while the organic zirconium crosslinking agent had controlled molar ratios of 1:4:3:3 of zirconium butoxide to ligand acetylacetone, triethanolamine, and glycerol. This work presents a systematic analysis of the chemical structure, microstructure, delayed crosslinking performance, temperature resistance, and shear resistance of the gel system. The study found that the crosslinking ratio of 100:2 resulted in a controllable delayed crosslinking time of the gel formed by the organic zirconium crosslinking agent and 4.0 g/L KGM/HPAM thickener within 5–25 min at room temperature. The viscosity remained above 81 mPa·s even after shearing for 100 min at 140°C and 170 s−1. These findings provide a useful reference for the application of organic zirconium crosslinked KGM/HPAM gel system in the petroleum fracturing field. [ABSTRACT FROM AUTHOR]

A novel bio‐based carbon forming agent (Mg@PA‐CS) containing P and N elements was were synthesized using the complexation characteristics of chitosan (CS) and phytate (PA). The flame retardant behavior of poly(lactic acid) (PLA)/Mg@PA‐CS/APP composites (addition of 20 wt% of different ratios of Mg@PA‐CS and APP to polylactic acid composites) were investigated by the limiting oxygen index (LOI), vertical burning test (UL‐94), cone calorimetry test (CCT), and thermogravimetric analysis (TGA). Due to the biphasic flame retardant and synergistic effect, since the 20 wt% flame retardant system (Mg@PA‐CS:APP = 1:2), PLA composites passed the UL‐94 test V‐0 rating, reached 34% LOI value. The peak heat release rate (PHRR) and total heat release rate (THR) were reduced to 1/2 of the pure PLA, char residue could be as high as 11.49% at 800°C. Moreover, the flame‐retardant mechanism of PLA composites during thermal decomposition was analyzed using a scanning electron microscope (SEM) and the coupling techniques of TGA linked with FT‐IR (TG‐FTIR). [ABSTRACT FROM AUTHOR]

Poly (styrene‐b‐(ethylene‐co‐butylene)‐b‐styrene) (SEBS) has been widely studied in the field of anion exchange membranes (AEMs) due to its superior flexibility and chemical stability, but the poor dimensional stability of functionalized SEBS restricts its further application. Thus, we adopt an effective strategy to reinforce AEMs based on SEBS via grafting poly (2,6‐dimethyl‐1,4‐phenylene oxide) (PPO) using Williamson ether synthesis reaction. With the addition of PPO, grafted membranes exhibit outstanding comprehensive properties, such as mechanical strength, chemical stability, especially dimensional stability. SEBS‐PPO‐QA‐1 grafted membrane with the highest content of PPO showed the best tensile strength (20.54 MPa), and restrained swelling behavior (swelling ratio of 4.81% at 25°C). Moreover, the conductivity retention of SEBS‐PPO‐QA‐1 grafted membrane is up to 92.71% at 80°C after 10 days alkaline treatment. The ion exchange capacity of SEBS‐PPO‐QA‐3 grafted membrane is 1.719 mmol/g, and the ionic conductivity of SEBS‐PPO‐QA‐3 grafted membrane reach 58.27 mS/cm at 80°C and 25.53 mS/cm at 20°C. Therefore, the SEBS‐PPO‐QA‐X grafted membranes, which combine the advantages of PPO and SEBS, are promising in AEM application. [ABSTRACT FROM AUTHOR]