Facile fabrication of hydrolysis resistant phosphite antioxidants for high-performance optical PET films via in situ incorporation

Phosphite antioxidants are extensively used in polyester industry due to extraordinary antioxidative and chromaticity protection capabilities. Unfortunately, they are highly susceptible to hydrolysis leading to reduced antioxidative activity, which remains unsatisfactorily addressed so far. In this work, we have demonstrated the fabrication of hydrolysis resistant hybridized phosphite antioxidants (PSLDH) by physically melt-blending with layered double hydroxides (LDH) based on the hydrolysis mechanism. X-ray diffraction measurements indicate that basically phosphite antioxidants are physically hybridized with the LDH. Accelerated hydrolysis results show that as-fabricated hybridized phosphite antioxidants show much superior anti-hydrolysis capability to the unmodified counterpart because the basic LDH can neutralize the phosphoric acid created during hydrolysis, thus effectively prohibiting the self-catalytic effect. High performance optical poly(ethylene terephthalate) (PET) materials are then synthesized by in situ adding PSLDH in the polycondensation process. Only adding 0.05   wt% of the PSLDH containing 10   wt% of LDH can remarkably improve the anti-oxidative and chromaticity performances of the resultant PET. This work provides an innovative methodology for developing high-performance value-added chemical additives via facile physical hybridization.