Recent growth of stage count of hydraulic fracturing has led to the increase in time and cost for a well completion. Simplifying time consuming process is a key for economic success. The use of degradable materials for components of downhole tools could provide several attractive advantages, such as eliminating or simplifying the recovery process of the tools. Polyglycolic acid (PGA), a hydrolyzable polymer, is a material suitable for such components and has already used in some applications including frac balls because of its high mechanical strength and appropriate degradation characteristics. In low-temperature wells close to the glass transition temperature of PGA however, there may be the potential risk, such as tool breakage during installation or stimulation due to the changes in the mechanical properties of PGA at low temperatures. This paper will focus on the improvement of the impact strength of PGA. Through an extensive study of modifiers, an elastic additive with high compatibility to PGA has been identified. Morphological studies of mixtures showed finely dispersed domains of the additive within a PGA matrix. The impact strength of the mixture was 2 times higher than that of neat PGA. A formulation was found optimizing this impact strength versus other mechanical properties of the mixture, while leaving degradability, processability and machinability basically equivalent with neat PGA. The improvement of the impact strength would broaden the applicability of PGA tooling and help to reduce the cost and time in well completion process at low temperature wells.
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