Wang Xiaoliang, Xu Mingbiao, Qin Yi, Song Jianjian, Chen Rongyao, Yin Zhong
School of Petroleum Engineering, Yangtze University, Wuhan 430100, China.
National Engineering Research Center for Oil and Gas Drilling and Completion Technology (Yangtze University), Wuhan 430100, China.
Polymers (Basel). 2023 Jul 23;15(14):3130. doi: 10.3390/polym15143130.
The integrity of oil well cement sheaths is closely related to the long-term production safety of oil and gas wells. The primary material used to form a cement sheath is brittle. In order to reduce the brittleness of oil well cement and improve its flexibility and resistance to stress damage, nano-silica was used to modify polymer elastic particles, and their properties were analyzed. The influence of the modified polymer particles on the properties of oil well cement-based composite materials was studied, and the microstructure of the polymer particle cement sample was analyzed. The results showed that nano-silica effectively encapsulates polymer particles, improves their hydrophilicity, and achieves a maximum temperature resistance of 415 °C. The effect of the modified polymer particles on the compressive strength of cement sample is reduced. Polymer particles with different dosages can effectively reduce the elastic modulus of cement paste, improve the deformation and elasticity of cement paste, and enhance the toughness of cement paste. Microstructural analysis showed that the polymer particles are embedded in the hydration products, which is the main reason for the improvement in the elasticity of cement paste. At the same time, polymer particle cement slurry can ensure the integrity of the cement sample after it is impacted, which helps to improve the ability of oil well cement-based composite materials to resist stress damage underground.
油井水泥环的完整性与油气井的长期生产安全密切相关。用于形成水泥环的主要材料是脆性的。为了降低油井水泥的脆性，提高其柔韧性和抗应力损伤能力，采用纳米二氧化硅对聚合物弹性颗粒进行改性，并对其性能进行了分析。研究了改性聚合物颗粒对油井水泥基复合材料性能的影响，并对聚合物颗粒水泥样品的微观结构进行了分析。结果表明，纳米二氧化硅有效地包裹了聚合物颗粒，提高了其亲水性，实现了最高415℃的耐热性。改性聚合物颗粒对水泥样品抗压强度的影响降低。不同用量的聚合物颗粒能有效降低水泥浆的弹性模量，改善水泥浆的变形和弹性，增强水泥浆的韧性。微观结构分析表明，聚合物颗粒嵌入水化产物中，这是水泥浆弹性提高的主要原因。同时，聚合物颗粒水泥浆在受到冲击后能保证水泥样品的完整性，有助于提高油井水泥基复合材料在地下抵抗应力损伤的能力。
