New organic-inorganic hybrids as multifunctional additives to improve ethylene-norbornene (EN) composite stability

In this study, new multifunctional organic-inorganic pigments were synthesized by the complexation of carboxlic azo dyes (D1, D2) with aluminum-magnesium hydroxycarbonate (LH) and were applied as colorants in ethylene-norbornene copolymer (EN). The structures of the hybrid pigments were analyzed by X-ray diffraction (XRD), secondary ion mass spectrometry (TOF-SIMS), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). X-ray diffraction revealed that the hybrid pigments had developed new crystalline structures and showed the presence of additional peaks on their diffraction patterns. Moreover, TOF SIMS confirmed that the modification had been successful, with the formation of dye-metal complexes embedded in the LH structure. The EN composites with hybrid pigments were subjected to accelerated UV aging. Alterations were monitored by Fourier transform infrared spectroscopy (FT-IR), spectrophotometry, differential scanning calorimetry (DSC) and mechanical tests. It was found that the EN composites containing hybrid pigments showed approximately 4 times higher tensile strength than both EN and an EN sample with unmodified LH under 250 h of UV irradiation. Adding 2 %wt of the multifunctional hybrid pigments to EN copolymer significantly enhanced the aging resistance and thermal stability of the resulting composites.
Source: Polymer Degradation and Stability - Category: Chemistry Source Type: research