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It is difficult to recycle classic thermosetting plastics. Although some of them can be reprocessed, the mechanical properties decline linearly after processing. In addition, most thermosetting plastics are not environmentally friendly and difficult to degrade, resulting in a lot of pollution and limiting their practical application potential. In this paper, the prepolymer is synthesized by using castor oil (CO), hydroxyl terminated polydimethylsiloxane (PDMS‐OH), and toluene diisocyanate (TDI). Using 4,4'‐diaminodiphenyl disulfide (ODD) as a chain extender with dynamic disulfide bond and aniline (An) as a blocking agent, polysiloxane‐aminoester (SiCPUO) with recyclable function under DMF induction was prepared. The effect of the amount of rigid chain extender (ODD) containing disulfide bond on the properties of SiCPUO was studied, its heat resistance will first increase and then decrease with the increase of ODD content, especially the mechanical properties are more obvious, this trend has never been reported before; the mechanical properties and recyclability of SiCPUO are tested, and the comprehensive performance of SiCPUO2 is the best, the tensile strength is 0.84 MPa and the elongation at break was 65.81%; the solubility test of different solvents showed that it has recyclability, recovery rate is 95%;the material has self‐healing function, the repair efficiency is up to 95%. [ABSTRACT FROM AUTHOR]

Self‐healing poly(siloxane‐urethane) materials have garnered significant interest among researchers, owing to their superior resistance to high and low temperatures, solvents, corrosion, and biocompatibility. Nevertheless, most existing self‐healing poly(siloxane‐urethane) materials face challenges, including limited repair conditions and the challenge of balancing mechanical properties with repair efficiency. In this research, we introduced hydrogen bonds, metal coordination bonds, π–π bonds, and reversible ring structures into the poly(siloxane‐urethane) system through molecular chain structure design, successfully developing a multi‐dynamic cross‐linked poly(siloxane‐urethane) (PU‐Si), a development rarely reported in prior studies. This study examines the impact of varying amounts of hydroxyl‐terminated polydimethylsiloxane (PDMS‐OH) on the properties of PU‐Si. The results indicate that PU‐Si, regardless of the amount of PDMS‐OH added, can self‐healing under conditions of heating at 60 °C, and exposure to ultraviolet and infrared radiation. Specifically, when the PDMS‐OH addition reaches 1.0 g, the material exhibits superior mechanical properties and self‐healing efficiency, achieving a mechanical strength of 9.68 MPa and a self‐healing efficiency of 86.6 %. This material shows significant application potential in areas such as electronic skins, flexible sensors, and brain‐computer interfaces. [ABSTRACT FROM AUTHOR]

To clarify the evolution of thermal maturity and pore structure in continental organic-rich shales, calcareous shales of the Liaohe Basin (China) were pyrolyzed, and examined using Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), nitrogen sorption isotherms, and nuclear magnetic resonance (NMR) spectroscopy. The increase in Raman G-D band separation and decrease in Raman ID/IG ratio with increasing thermal maturity indicate that these parameters provide superior thermal maturity indicators. This is also confirmed by the good linear correlation of G-D band shifts and ID/IG with vitrinite reflectance (VR) and maximum temperature (Tmax), respectively. The relative detection accuracy (DA), sampling requirements (SR), sample preparation (SP), detection time (DT), and equipment requirement (ER) of VR, G-D band shifts, ID/IG, Tmax, FTIR, and XPS indicate that Raman analysis is a simple, quick, and robust method to evaluate thermal maturity. The moderate SR, complex SP, and long DT suggest that VR and Tmax are less widely applicable for characterizing thermal maturity. The FTIR and XPS techniques provide semi-quantitative maturity indicators with poor DA and high ER. Pores observed within organic matter and minerals under SEM indicate that an increase in thermal maturity not only affects the development of organic pores but is also beneficial for the formation of mineral dissolution pores, such as those formed during the transformation of Na0 95Ca016Al1 16Si2 84O8 to Na0 84Ca0 02Al1 02Si2 98O8, a process confirmed by XRD. The BET and NMR data also indicate that the development of pore structure is closely related to the evolution of thermal maturity in calcareous shale . During the initial stage, primary pores are filled by bitumen generated from kerogen; this leads to a decrease in transition pores, mesopores, and shale porosity, and reduced pore connectivity. Then, secondary nanoscale pores, transition pores, and mesopores increase with increasing thermal maturity. The peak in secondary porosity is consistent with the liquid hydrocarbon production rate peak, a process that increases shale porosity and leads to improved pore connectivity. The dissolution of minerals induced by organic acids may also contribute to this secondary porosity. With a further increase in thermal maturity, secondary porosity at the microscale is further developed, while transition pores and mesopores collapse, resulting in reduced pore connectivity. The poor pore connectivity that occurs at both low and high VR values may be more conducive to the preservation of shale oil and gas. This study is significant for research into the evolution of thermal maturity and pore structure in continental organic-rich shales. [ABSTRACT FROM AUTHOR]

Polyurethane is the main matrix material of polymer damping materials, but the damping temperature range is narrow, the effective damping temperature range does not match the working temperature of the material, and the elastic modulus is sensitive to temperature during glass transition, which is not conducive to safe use in a wide temperature range. In this paper, the polyurethane gradient material with the hard segment content continuously changing along the length direction was designed and prepared by the reaction injection method. Dynamic mechanical analysis (DMA) shows that the gradient structure greatly influences the comprehensive damping performance of polyurethane. While maintaining no significant decrease in mechanical properties, the gradient material extends the effective damping temperature range (TR) from 40.7°C (−32.3 ~ 8.4°C) for component A and 66.6°C (59.5 ~ 126.1°C) for component B to 139.5°C (−20.6 ~ 118.9°C). At the same time, the damping peak remains high (0.48), which is close to the higher damping peak of the B component of 0.56. The elastic modulus (E′) decreases slowly with the increase in temperature, which can better ensure the safety of the material. [ABSTRACT FROM AUTHOR]

This paper takes the ultra-low permeability sandstone reservoir of Jingbian oilfield in Ordos Basin as the research object, analyzes the petrological characteristics, diagenesis, physical characteristics and pore structure characteristics of the reservoir, and carries out reservoir sensitivity evaluation by using rock casting thin sections, X-ray diffraction, and sensitive flow experiments. The research results show that the ultra-low permeability Chang 6 sandstone reservoir has weak velocity sensitivity, medium-weak water sensitivity, weak salt sensitivity, weak alkali sensitivity and strong acid sensitivity; the damage mechanism of reservoir sensitivity mainly depends on the composition of clay minerals and pore structure after diagenesis. The clay mineral content from high to low is chlorite, illite, a small amount of illite / smectite layer, and kaolinite, of which the chlorite content is as high as 75 %; the reservoir has poor physical properties, the types of small hole-thin throat and small hole-fine throat. The reservoir is prone to blockage such as bridge plugging. Therefore, ultra-low permeability sandstone reservoirs are prone to different degrees of sensitivity. The reservoir characteristics are consistent with the reservoir sensitivity evaluation results.

A 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO) derivative is prepared. At first, an intermediate 4,4'‐((triazole)bis(azaneylylidene)bis(2,6‐dimethoxyphenol)) (SGA) is obtained from the Schiff‐base reaction between syringaldehyde (S) and 3,5‐diamino‐1,2,4‐triazole (GA). The further product DOPO‐SGA is then introduced into epoxy by blending to improve flame retardancy and mechanical properties. The flammability evaluation is implemented by limited oxygen index (LOI), UL‐94, and cone calorimeter tests. The presence of 3wt.% DOPO‐SGA increases the LOI to 33.2%, upgrades the UL‐94 rating to V‐0, and reduces the release of smoke and heat of epoxy. The tensile strength and impact strength are also enhanced after the introduction of DOPO‐SGA. The addition of 5% DOPO‐SGA increases the tensile strength and impact strength by 47% and 42%, respectively, compared with that of the control EP sample. It is suggested that the mechanical strengthening is ascribed to the ternary cross‐linked network among epoxy monomer, curing agent, and DOPO‐SGA. This work provides a feasible solution to obtain flame‐retardant epoxy resin with enhanced mechanical performance. [ABSTRACT FROM AUTHOR]

Deep energy fields in the Tahe Oilfield are studied and the relationship between energy fields and hydrocarbon migration and accumulation is discussed through the comprehensive analyses of energy field characteristics. Multi-phase tectonic stresses are the main controlling factor of the developmental morphologies of the present fractures. The characteristics of the present regional tectonic stress indicate that the Tahe Oilfield is a favorable area for hydrocarbon collection. The present pressure field of the Ordovician is a slightly low abnormal pressure system. The fluid potential characteristics show that there are two hydrocarbon migration trends: one is from east to west in part of the eastern area, and the other is from south to north in the whole southern area. The present formation water is of typical CaCl2 type. According to the formation water geochemistry, the Tahe Oilfield has a good seal capability, favorable for hydrocarbon accumulation and preservation. Aqueous inclusions indicate that homogenization temperatures are mainly 80–100°C, 120–130°C, and 150–170°C, therein, 80–100°C and 120–130°C represent two large scale hydrocarbon accumulation phases, Early Hercynian and Himalayan, and 150–170°C is controlled by tectonic event and Permian magmatic activities, representing a partial hydrocarbon accumulation event. 摘 要: 以塔河油田深层能量场为研究对象，通过系统分析能量场特征来探讨其与油气运聚的关系。研究认为，多期构造应力作用是塔河油田现今断裂发育形态的主控因素，现今区域应力场特征表明塔河油田是油气运移的有利指向区；奥陶系现今压力场整体上属于略偏低异常的压力系统，流体势特征显示油气运移存在东部自东向西局部性运移趋势以及南部由南向北区域性运移趋势；奥陶系现今地层水离子构成符合典型的CaCl2型水特征，地层水地化指标显示塔河主油区具有良好的封闭性，是油气聚集保存的有利区；盐水包裹体均一温度测试结果主要集中在80～100 ℃、120～130 ℃和150～170 ℃等3个温度段，前两个温度段分别对应于塔河油田2次大规模的油气成藏期：海西早期和喜马拉雅期，而最后一个温度段主要受控于构造变动和二叠系岩浆活动，代表了一期局部油气成藏事件。图7参22 Key words: Tahe Oilfield, deep carbonates, energy field, hydrocarbon migration, hydrocarbon accumulation

In order to improve the flame retardancy and antistatic properties of polyamide 6 (PA6) at as low amount of additives as possible, an integrated‐functional additive was synthesized by 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO) and multiwalled carbon nanotubes (MWCNTs). The results showed 2 wt% of DOPO‐MWCNTs distributed in PA6 formed an electric network and decreased volume resistivity sharply to 3.1 × 108 Ω cm. In other words, it helped PA6 to get to the percolation threshold of semiconductor. By using of 3 wt% DOPO‐MWCNTs, the severe dripping in burning of PA6 was almost controlled. The possible reason was also ascribed to the network formed by evenly dispersed DOPO‐MWCNTs, which strengthened the char structure and held severe dripping of PA6. As a result, the heat and smoke release were also suppressed obviously. The most important is that CO release was about half cut in CONE test. [ABSTRACT FROM AUTHOR]