Use of preceramic polymers for magnesium diboride composites

► We used polysiloxane copolymers for improving transport properties of MgB2. ► Polysiloxane-co-vinyl-ferrocene was used to insert magnetic nanoparticles. ► Cyclic polysiloxane-co-styrene leads to the best critical properties. ► Magnetic pinning is visible at high temperatures in samples with ferrocene.