HALS intercalated layered double hydroxides as an efficient light stabilizer for polypropylene

The thermal stability and migration resistance of light stabilizers are vital for their applications in plastics. Herein, a novel nano organic–inorganic hybrid light stabilizer with high thermal stability and low solubility was prepared by intercalating a synthesized hindered amine light stabilizer (HALS) with UV absorption capability into the interlayer galleries of MgAl layered double hydroxides (LDH) through co-precipitation method. The prepared HALS–LDH was characterized by XRD, FT–IR, SEM, TG–DTA and UV–vis, and was incorporated into the matrix of polypropylene (PP) via solvent casting method to prepare LDH/PP composite for light stability test. It was found that the synthesized HALS was successfully intercalated into the interlayer galleries of MgAl–LDH, forming an organic–inorganic hybrid material HALS–LDH with a mean size of 63 nm. HALS–LDH nanosheets were evenly dispersed in the matrix of PP, and the addition of HALS–LDH can retard the thermal decomposition of PP. Moreover, the incorporation of HALS–LDH significantly improved the light stability of PP and reduced the photo degradation of PP by about 83.2%. Therefore, the prepared novel HALS–LDH has potential application in the field of PP as an efficient and promising light stabilizer.