Study of Modified LDHs as UV Protecting Materials for Polypropylene (PP)

摘要

The degradation and color loss of different polymer products which are being used in open environment is mainly due to Ultraviolet (UV) light. In this work the possibility of using different UV light absorbing Layered double hydroxides (LDHs) for the protection of polypropylene (PP) against UV light degradation is explored. First, possible transition metal containing LDH were synthesized and organomodification with ion exchange method were performed. Successfully, Zn-Ti LDH was synthesized and organically modified by Dodecylbenzene sodium sulfonate (SDBS) and Lauric acid (LA). Four combinations of Zn-Ti, Zn-Sn, Zn-Ti SDBS and Zn-Ti LA LDHs were used in PP composite preparation. Decomposition, UV absorption properties and photooxidation of all four composites and pure PP were detemined. Most significant results were obtained by the addition of Zn-Ti-SDBS LDH in PP. Thermal stability of PP was increased by 70 °C by the addition of only 5 % Zn-Ti-SDBS LDH.