Affiliation:
1. College of Materials Science and Engineering Beijing University of Chemical Technology No. 15 Beisanhuan Road East Chaoyang District Beijing 100029 China
2. Beijing National Innovation Institute of Lightweight LTD, China Academy of Machinery Science and Technology Group Yard 10, Yanqihe West 1st Road Yanqi Economic Development Zone Huairou District Beijing 101407 China
3. State Key Laboratory for the High‐Efficient Development of Offshore Oil CNOOC Research Institute Co., Ltd Building 1, Courtyard 6, Taiyanggong South Street Chaoyang District Beijing 100028 China
Abstract
AbstractLost circulation is a critical issue in drilling. This work reports the investigations on shape memory epoxy polymers (SMEPs) with high switching temperatures, and good thermal, mechanical and shape memory properties for plugging in deep drilling. The SMEPs are produced by curing diglycidyl ether of bisphenol A (DGEBA) and castor oil glycidyl ether (COGE) with a flexible poly(oxypropylene) diamine (D230) and a rigid 4, 4′ ‐diaminodiphenyl methane (DDM). Increasing D230 contents or using COGE, glass transition temperature (Tg, 93–163 °C, DMA analyses) and crosslink density of SMEPs are reduced, shape recovery rate is increased, while tensile strength, elongation at break and impact strength are improved. Further, shape memory epoxy syntactic foams (SMEFs) with high‐temperature adhesion are developed by introducing polymer microspheres into SMEPs. The SMEFs have compression ratio of 52–58%, and expansion ratio of 100% by adding 2% wt. microspheres. They retain the Tg and thermal stability of SMEPs, and show a delayed, slower recovery than SMEPs. Long fracture plugging experiments exhibit that a pressure‐bearing capability of 8.99–9.81 MPa is achieved with SMEFs in sealing fracture slots at a high temperature.
Subject
Materials Chemistry,Polymers and Plastics,Organic Chemistry,General Chemical Engineering