Investigation on the mechanical and optical properties of kraft paper coated with a combination of pectin, polyvinyl alcohol and nano titanium dioxide

In this research, at the first stage of the study, the Pectin was reinforced with Polyvinyl Alcohol (PVA), and at the second stage, a combination of PVA reinforced Pectin and Nano Titanium dioxide (TiO2) was used to coat the packaging paper. After the coating process, the mechanical and optical properties of the samples were studied. Results showed that the second stage coating mixture enhanced the mechanical strength parameters of the papers (Tear from 16.55 to 17.85 KPa.m2/g, Tensile from 56.38 to 69.97 Nm/g and, Burst from 2.806 to 4.037 mNm2/g). In the brightness test, the paper samples coated with the first stage mixture showed a brightness decrease, while samples coated with the second stage mixture showed a brightness increase (the minimum brightness was 16.99% and the maximum brightness was 20.09%). On the other hand, the opacity of the papers coated with the second stage mixture was increased (from 97.88% to 98.67%).