Effect of Modified Carbon Black on the UV/IR Screening Ability of Poly(ethylene terephthalate) Transparent Films

摘要

The mixed solution of poly (ethylene terephthalate) (PET)/carbon black (CB) and PET/modified CB (m-CB) were coated on glass substrates to fabricate light screening films. m-CB was prepared using a solid phase modification method through mechanical blending of CB and 2-(2'-Hydroxy-5'-methyIphenyl)-benzo-triazole (UV-P) in weight composition of 50 : 50. The results of dynamic light scattering (DLS), optical microscopy, and scanning electron microscopy (SEM) showed that the modification of CB obviously reduced the particle and aggregate sizes of CB, leading to better dispersion of m-CB in PET films. Fourier transform infrared spectroscopy (FTIR) proved that UV-P was grafted on CB after blending and changed the molecular structure of CB. Ultraviolet-visible-lnfrared (UV-vis-IR) spectrophotometer tests showed that the UV/IR absorption property of the films improved obviously while the visible light transmittance reduced gradually with the increase of m-CB content from 0.5 to 6 wt%. Differential scanning calorimeter (DSC) results showed the addition of 4 wt% m-CB decreased the crystallinity of PET matrix, which effectively inhibited the destruction of the film transparency with the addition of more CB.