Preparation and characterization of a high molecular weight UV‐stabilizer based on a derivative of 2,4‐dihydroxybenzophenone and its application in polymer materials

In this study, a polymerizable UV‐stabilizer, 2‐hydroxy‐4‐(3‐methacryloxy‐2‐hydroxylpropoxy)benzophenone (BPMA), was synthesized using 2,4‐dihydroxybenzophenone (UV‐0) and glycidyl methacrylate (GMA). It was copolymerized with methyl methacrylate (MMA) to prepare poly(MMA‐co‐BPMA) by emulsion polymerization. The composition and characteristics of poly(MMA‐co‐BPMA) were determined by using proton nuclear magnetic resonance (1H‐NMR), gel permeation chromatography (GPC), and ultraviolet‐visible absorption spectroscopy (UV–vis). Further, the obtained poly(MMA‐co‐BPMA) was used as a high molecular weight UV‐stabilizer and was blended with PVC to prepare PVC/poly(MMA‐co‐BPMA) films. These films were presented under UV light, using PVC film as standard substance. Insoluble substance, GPC, and color difference were used to characterize UV degradation. The results show that poly(MMA‐co‐BPMA) is an effective high molecular weight UV‐stabilizer. To detect the migration of poly(MMA‐co‐BPMA), water extraction and heat migration test were used to accelerate the movement of poly(MMA‐co‐BPMA). As a reference, these tests were also carried out on PVC/UV‐0 film. The results show that poly(MMA‐co‐BPMA) has very small migration, while nearly 80% UV‐0 migrated out from the plastic matrix after the experiments.