Impact of impregnation and bleaching on the surface hardness of oak (Quercus petraea L.) wood

• Published in: Journal of applied polymer science Vol. 93; no. 2; pp. 498 - 504
• Main Authors: Keskin, Hakan, Atar, Musa, Güçlü Yavuzcan, H.
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 15.07.2004; Wiley
• Subjects: Applied sciences; coatings; Exact sciences and technology; hardness; Physicochemistry of polymers; Polymer industry, paints, wood; surfaces; Technology of polymers; coatings; Coating material; Wood; Bleaching; surfaces; Polymer; Hardness
• ISSN: 0021-8995; 1097-4628
• DOI: 10.1002/app.20434

The impact of impregnation and bleaching on the hardness of varnish layers on oak (Quercus petraea L.) wood was investigated. A number of solutions [sodium hydroxide (NaOH) and hydrogen peroxide (H2O2); NaOH, calcium hydroxide, and H2O2; NaOH, magnesium sulfate, and H2O2; sodium bisulfate and H2C2O4 · 2H2; sodium silicate and H2O2; and potassium permanganate, sodium bisulfate, and H2O2] were applied at a concentration of 18% to bleach both impregnated [Tanalith‐CBC (T‐CBC) or Imersol‐WR 2000 (I‐WR 2000)] and unimpregnated (natural) wood panels. Subsequently, a water‐based varnish (WB) was coated over the samples, and the hardness of the varnished layers was determined in accordance with ASTM D 4366. Among the samples that were varnish‐coated without bleaching, T‐CBC/WB yielded the highest hardness (59.50), whereas I‐WR 2000/WB exhibited the lowest (49.17). However, among the samples varnish‐coated after bleaching, the highest (56.50) and lowest (40.83) varnish hardness values were obtained with T‐CBC/solution 2/WB and I‐WR 2000/solution 4/WB, respectively. All the chemicals used for the bleaching process reduced the surface hardness. However, after the varnish coating, except for solutions 4 and 6, all the solutions showed hardness values similar to those of varnish‐coated natural (control) samples. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 498–504, 2004