Rapid Self‐Expansion Behavior of the PMMA‐Based Bone Cement with P(MMA‐AA)‐GO Nano‐Units

The volume shrinkage of polymethylmethacrylate (PMMA) bone cement is typically addressed by incorporating additives into the matrix. However, the maximum water absorption and swelling capacity of the composite bone cement are not sufficiently improved due to its rapid solidification. In this work, poly(methyl methacrylate‐acrylic acid)‐grafted graphene oxide [P(MMA‐AA)‐GO] nano‐units with the microsphere‐lamellar structure are synthesized, and then P(MMA‐AA)‐GO bone cement (PGBC) is fabricated. The rate of absorption and swelling of PGBC are significantly promoted by the microsphere–lamellar structure of P(MMA‐AA)‐GO nano‐units, achieving maximum absorption and swelling capacity of PGBC before its solidification. PGBC 4 exhibits the maximum equilibrium simulate body fluid (SBF) absorption ratio and equilibrium swelling ratio of 90.2% ± 1.7% and 92.5% ± 4.5%, respectively. Interestingly, the maximum compression strength of the composite before immersion is also observed in PGBC 4 with a value of 77.2 ± 1.1 MPa. The enhanced compression strength of PGBC overcomes the bottleneck of the decreased compression strength resulting from the enhanced absorption behavior. Therefore, PGBC with rapid self‐expansion behavior and improved mechanical properties can not only reduce the injection volume to avoid leakage in the clinic but also provide sufficient mechanical support, which has promising application potential in the clinical setting. The poly(methyl methacrylate–acrylic acid)‐grafted graphene oxide [P(MMA‐AA)‐GO] nano‐units with the microsphere–lamellar structure are synthesized, and water‐absorption and swelling capacity are maximally developed before solidification of composite bone cement. Meanwhile, there is enhanced compression strength of PGBC as the introduction of P(MMA‐AA)‐GO nano‐units overcomes the bottleneck of the decreased compression strength resulting from the improved absorption behavior.