## Abstract Composite electrodes based on iron(III) oxide, Fe~2~O~3~, carbon powder and epoxy resin have been prepared and characterized using electrochemical methods and X‐ray photoelectron spectroscopy (XPS). Initially composite electrodes were made by mixing micron sized carbon powder surface wi
The application of hydrogen peroxide in composite repair
✍ Scribed by Federica Papacchini; Francesca Monticelli; Ivana Radovic; Nicoletta Chieffi; Cecilia Goracci; Franklin R. Tay; Antonella Polimeni; Marco Ferrari
- Publisher
- John Wiley and Sons
- Year
- 2007
- Tongue
- English
- Weight
- 297 KB
- Volume
- 82B
- Category
- Article
- ISSN
- 1552-4973
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✦ Synopsis
Abstract
This study examined the influence of different surface conditioning methods on composite‐to‐composite microtensile bond strength. Thirty two‐year old composite resin discs were randomly divided into three groups according to the different mechanical/chemical surface pretreatment tested: (1) 38% hydrogen peroxide (H~2~O~2~)‐treatment; (2) 50‐μm aluminum oxide sandblasting; (3) no treatment. Depending on the intermediate agent applied, two subgroups were created: (A) three‐step adhesive system; (B) prehydrolyzed silane coupling agent + three‐step adhesive system. Microtensile bond strength measurements were performed and the data were statistically analyzed with Kruskall–Wallis Analysis of Variance and Dunn's multiple range test for post hoc comparisons (p < 0.05). Failure mode was evaluated with a scanning electron microscope. Changes in composite surface topography after H~2~O~2~ treatment were also investigated. Composite repair strength did not benefit from H~2~O~2~ treatment and adhesive application. Preliminary sandblasting significantly improved interfacial bond strength regardless of the intermediate agent applied. No changes in surface texture were produced after H~2~O~2~ treatment. An atypical fracture pattern was detected at the interfacial level between H~2~O~2~‐treated composite surfaces and the overlying adhesive and composite. H~2~O~2~ treatment affected the composite‐to‐composite repair strength: a compromised resin polymerization may occur, resulting in a poor interfacial quality and a weak bond. Sandblasting still remains a reliable technique for composite repair. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2007
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