Data for: Development of Antibacterial Powder Coatings Using Single and Binary Ion-exchanged Zeolite A Prepared from Local Kaolin
Description
Antibacterial electrostatic powder paint coating with intended esthetic criteria was specially formulated for industrial applications using single (Ag+) and binary exchanged (Ag+ and Zn2+) zeolite A, which was prepared from local kaolin resources. Optimization studies on reaction parameters were conducted to obtain the most crystalline zeolite A from kaolin. The silver and zinc exchanged zeolite A samples prepared from kaolin were introduced as filler into the paint matrix during the electrostatic powder coating process. The antibacterial coatings were produced with thermosetting polymers through electrostatic spray deposition process, in which powder paint mixture was adhered onto metal substrate by spraying electrostatically. The antibacterial thermosetting powder paint was preparedinitially in a dry form by mixing metal exchanged zeolite with the powder paint raw materials. Color analysis was also performed to these coatings in order to meet the least discoloration criteria, which is relevant to judge the quality of the coatings for industrial use. Accordingly, for any produced powder paint to be in an acceptable esthetic scale, the ∆E value was set to be in the range of 0 and +1. For this purpose, ∆E values of all prepared coatings for silver and zinc ion-exchanged zeolite samples were measured. Upon comparing the paint coatings that contain only Ag+ ion (A1-C and A3-C), it was seen that the ∆E value for A3-C was around +1.53 taking this particular zeolite formulation (0.8 wt.% zeolite loading with 6 wt.% Ag+) to out of pre-established esthetic range. For the sake of clarity, a coated sample with significantly higher Ag+ content was also examined. Upon increasing the Ag+ content to 23 wt.% (0.8 wt.% zeolite loading), significant deterioration was observed whose ∆E value was measured to be +3.81. Another test sample was prepared keeping Ag+ content constant at 6 wt.% but increasing zeolite loading amount to 3.2 wt.% in the paint formulation. This protocol caused even a more significant deterioration in color with a ∆E value of +7.47. These two samples showed remarkable yellowish dark colors. Accordingly, increasing Ag+concentration in zeolite and also zeolite concentration in the paint formulation for single Ag+ ion-exchanged zeolites lead to higher ∆E values and ruined visual inspection of these coatings. Thus, obtaining antibacterial efficacy in composites with increased Ag+ content or Ag+-containing matrix materials may not meet the industrial criteria and should be assessed with special care. ∆E values of binary ion-exchanged samples were observed to be close to zero with much improved coloring qualities similar to the sample that includes no zeolite. It was seen that addition of Zn2+ ions besides Ag+ ions into zeolite framework enhanced the visual appearance of the coatings (A2-C and A4-C).