Polybenzoxazine/organoclay composite coatings with intercalated structure: Relationship between solubility parameters and corrosion protection performance

Two organoclays (Nanocor's nanomer I.44P and I.34TCN) were incorporated into polybenzoxazine (PBz) coatings to prepare composite coating with intercalated structure. XRD, AFM, water contact angle and electrochemical techniques were employed to assess the coatings' performance. Solubility parameters were calculated to evaluate the interaction between PBz and pillaring agents in organoclays, which can be used to well explain the composites' structure and performance. The system with the pillaring agent, which has better miscibility with PBz chains, exhibit denser layer structure as well as better corrosion resistance, leading to a reduction of 4 orders of magnitude on corrosion rate with respect to bare mild steel compared to the other system.