The preparation and absorbing properties of controllable porous polymer microspheres @ MWCNTs absorber with lightweight characterization

Poly(styrene-sodium p-styrene sulfonate) microspheres with porous morphology were prepared by dispersion polymerization and seed swelling selecting two monomers of sodium p-styrene sulfonate and styrene, which are denoted as P(St-NaSS). The method is simple and easy to effectively control the pore structure microspheres. The SEM results showed that the surface morphology of P(St-NaSS) microspheres is in porous, and the diameter of pores is about 0.5 μm. In this paper, the influence of swelling time on the pore size was investigated. The SEM results indicated that the longer the swelling time, the larger the pore size of microspheres. The absorbing hybrids of swelled multi-porous P(St-NaSS) @MWCNTs and non-swelled P(St-NaSS)@MWCNTs with three-dimensional conductive network were assembled by π bond stacking effect, and study the strength of its absorption of electromagnetic waves. Compared with P(St-NaSS)@MWCNTs hybrids, the multi-porous P(St-NaSS) hybrids exhibited better absorbing performance, the reflection loss is -35.24 dB at 7.15 GHz at 2 mm thick, while the reflection loss of P(St-NaSS)@MWCNTs is -24.63 dB. The experimental results show that the existence of porous in wave-transparent microspheres played an important role in improving the impedance matching, increasing the path of multiple reflection scattering, which is beneficial to improve the absorption of MWCNTs.