A novel degradable sealing material for the preparation of dissolvable packer rubber barrel

Abstract

To develop dissolvable packer rubber barrel is a key technology for realization of green oil drill engineering. During this experiment, a novel degradable rubber sealing material from MPUR/HNBR composite was prepared by physical mixing and chemical cross-linking with different parts of HNBR. The effect of blending ratio on the vulcanization characteristics, mechanical properties, compatibility, thermal stability, and dissolution characteristics of the composites were investigated. The results showed that when the MPUR/HNBR blend ratio changed from 80/20 to 60/40, the cross-linking degree of composites decreased gradually and the mechanical properties decreased. MPUR and HNBR have compatibility properties in a certain blending range, and the addition of HNBR led to an improvement in the thermal stability of composites. When immersed in a water medium at 100 °C, the tensile strength of pure MPUR decreased sharply in 12 h from 30 MPa to 3 MPa, its short service life time didn’t meet the need of engineering. After composed by HNBR, the tensile strength retention increased from 27.0% to 52.1% immersion for 24 hours. In addition, the composite can maintain high tensile strength between 48 and 168 h, its superior long service life time fully meet the sealing requirements. The possible degradable mechanism in water medium was offered.