In the presented work, the two-phase copolymer microspheres based on divinylbenzene (DVB) and the second comonomers with functional groups of different polarity: MMA (methyl methacrylate), NVP (N-vinyl-2-pyrrolidone), and TMVS (trimethoxyvinylsilane) were synthesized in the suspension polymerization method. The 1:1 M ratio of the monomer mixture was applied as a representative and balanced composition to obtain polymers with well-developed porosity. The study aimed to investigate how the structure of the comonomer influences the morphological, textural, structural, acid-base, and thermal properties of the resulting polymer material in the form of microspheres. For this purpose, low-temperature nitrogen sorption, small-angle X-ray scattering (SAXS), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) and Raman spectroscopies, potentiometric titration, and thermal analysis were performed. The results showed that the structural and thermal properties of novel polymers significantly depend on the type of the second phase. The adsorption efficiency of the polymer adsorbents: DVB-co-MMA, DVB-co-NVP, and DVB-co-TMVS towards aqueous solutions of phenol (P), 4-nitrophenol (4-NP), and nitrobenzene (NB) was investigated. The selected adsorbates allowed to reveal adsorption mechanisms in the investigated systems: π–π interactions, hydrogen bonding, and dipole interactions. The effectiveness in sorption processes towards organic aromatic substances was the lowest for DVB, whereas, for bi-phase copolymers, an improvement in adsorption properties was found. The relative adsorbate losses from aqueous solutions confirm the highest adsorption for nitrobenzene. Phenol revealed the weakest affinity to all polymers (am = 0.62–0.75 mmol/g), and nitrobenzene was favorably adsorbed on all materials (am = 1.21–1.36 mmol/g). For the studied bi-polymer-aromatic organic compound systems, a dual nature of adsorption processes was observed. Physical adsorption in the porous space was dominated by π–π interactions between the aromatic rings of the adsorbates and adsorbents. Furthermore, some adsorbate molecules were adsorbed through functional group interactions. The presence of surface groups in the polymers also increases the selectivity of these materials in the adsorption process.