PHOTOCHROMIC POLYPROPYLENE COMPOSITE, PREPARATION METHOD FOR SAME, AND APPLICATIONS THEREOF

摘要

Disclosed is a photochromic polypropylene composite, comprising the following components in terms of parts by weight: a polypropylene resin 96.5-98.5 parts and a photochromic microcapsule 0.5-2.5 parts. The core material of the photochromic microcapsule is a spiropyran, the wall material is a melamine formaldehyde resin, the wall material is formed by polymerizing formaldehyde and melamine, and the molar ratio of formaldehyde/melamine is 2.5/1-3/1. First, melamine and formaldehyde undergo an addition reaction in an environment of pH 7.5-8.5 to produce a hydroxymethyl melamine prepolymer, then a photochromic material spiropyran compound is dispersed in sodium dodecyl sulfate aqueous solution of a concentration of 0.2-1.0 wt%, then the hydroxymethyl melamine prepolymer is added to the solution, and the solution is regulated to a pH of 5.5-6.5 to produce a microcapsule emulsion, which is reacted at 80-90 °C for 3 h, rinsed, suction-filtered, and dried to produce the photochromic microcapsule. The photochromic polypropylene composite is capable of withstanding long-term exposure to sunlight, steadily changes colors back and forth, has great long-term weather resistance, and is widely applicable in interior and exterior decorative accessories for a vehicle.