实验研究了酚醛树脂冻胶在搅拌剪切和振荡剪切条件下的动态成胶过程、动态成胶时间、临界成胶剪切速率及剪切对剪切后静置成胶粘度的影响,结果表明:不同剪切条件下酚醛树脂冻胶体系交联反应过程均经历了诱导、成胶、稳定、下降等4个阶段,与静态成胶相比多了下降阶段,并且相同配方的冻胶体系搅拌剪切作用强于振荡剪切；随着聚合物和交联剂用量增大,冻胶体系初始成胶时间和最终成胶时间均缩短,与静态成胶相比,冻胶体系初始成胶时间在低剪切速率下缩短,而在高剪切速率下延长；相同配方的冻胶体系在搅拌剪切下的临界成胶剪切速率小于其在振荡剪切下的临界成胶剪切速率；在诱导阶段剪切对静置后冻胶体系粘度没有影响,因此在现场注冻胶过程中注入时间应控制在诱导阶段之前.%Several aspects of phenolic resin gel were experimentally studied in the stirring and oscillatory shear modes,such as dynamic gelling process,dynamic gelation time,critical gelling shear rate and effects of shearing on standing gel viscosity after shearing.The results have shown that:(1) In different shear modes,there are four stages in the crosslinking process of phenolic resin gel systems,i.e.induction,gelation,stabilization and decline,with the decline stage being extra compared with the static gelation process,and the impact of stirring shear is stronger than that of oscillatory shear for the gel systems with the same formula; (2) With increasing the polymer and crosslinker,both initial and final gelation time of the gel system will decrease,and compared with the static gelation,the initial gelation time will decrease in a lower shear rate and increase in a higher shear rate; (3) For the gel systems with the same formula,critical gelling shear rate in the stirring shear mode will be lower than that in the oscillatory shear mode; (4) During the induction stage,there will be no impact of shearing on the standing viscosity of the gel system,and the gel injection time should be before the induction stage in any field operation.
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