A one-pot strategy for the preparation of fire-retardant poly(propylene carbonate) by terpolymerization of CO2, propylene oxide and chlorendic anhydride

A functional monomer chlorendic anhydride (CA) with flame retardancy was added to the polymerization reaction between CO 2 and propylene oxide (PO) to form a terpolymer plastic polycarbonates (PPCCA) for the first time. Compared with conventional poly(propylene carbonate) (PPC), the synthesized PPCCA exhibited excellent thermal properties, mechanical properties , dimensional stability, high degradation and flame retardant (FR) properties. When the CA content was increased to 5 mol% (with respect to PO, except specially stated), the 5% weight-loss degradation temperatures ( T d , - 5%), the maximum weight-loss degradation temperatures ( T d , max ) and the glass transition temperature ( T g ) of PPCCA were increased to 235 ℃, 345 ℃ and 44 ℃, respectively. Additionally, in the CA content range of 0–5 mol%, the tensile strength of PPCCA increased to 26.7 ± 1.4 MPa and the elongation at break decreased to 144.4 ± 1.2%. Furthermore, within the same content range (0–5 mol%) of CA, the hot-set elongation (Δ L h ) and permanent deformation (Δ L p ) were reduced to 95% and 50%, respectively. The PPCCA exhibited good degradability as well. In terms of FR properties, the limiting oxygen index (LOI) of PPCCA (with 5 mol% CA, PPCCA5) was 33.5%, with which the vertical combustion test level turned out to be at the highest level (V-0), which truly improved the flame retardancy of the polymer.