Chemical Durability and Structural Proprieties of the Vitreous Part of the System xCaO-(40-x)ZnO-15Na<sub>2</sub>O-45P<sub>2</sub>O<sub>5</sub>

Abstract

The influence of CaO on the glass forming characteristics and properties of Na2O-CaO-ZnO-P2O5 glasses has been investigated. According to the studies that we performed on phosphate based glass within system xCaO-(40-x)ZnO-15Na2O-45P2O5 (10 ≤ x ≤ 30; mol%), it was found that the increase of CaO and substitution of ZnO can give a good chemical durability. Both Cristallographies X-ray and IR spectroscopy have confirmed the structure change when the CaO content increases in the glass. This change results in the formation of metaphosphate and/or rings of metaphosphate groups at the expense of pyrophosphate. So it indicates the formation of Ca-O-P bonds in the network glass that replaces hydrated P-O-Na and P-O-P bands. The phosphate chains units can be bonded together in rings forming meta-phosphate groups. These rings likely lead to the formation of agglomerates of crystalline phases, which is the main cause of the increase in the chemical durability of the glasses when the CaO content increases. The latter may lead to wider use of these materials, especially in the biomedical field.

Correlation between Chemical Durability Behaviour and Structural Approach of the Vitreous Part of the System 55P<sub>2</sub>O<sub>5</sub>-2Cr<sub>2</sub>O<sub>3</sub>-(43-x) Na<sub>2</sub>O-xPbO

“…The chemical durability of the glass series 55P 2 O 5 -2Cr 2 O 3 -(43-x) Na 2 O-xPbO (with 8 ≤ x ≤ 38 mol %) was de-termined by measuring the dissolution rate (D R ) of glasses immersed for 20 consecutive days in 100 ml of distilled water heated to 90˚C [6] [10]. The dissolution rate is defined as the loss of weight of the glass expressed in g•cm −2 •min −1 .…”

Reduction of Hygroscopicity in Zinc-Calcium-Phosphate Glass via Iron-Oxide Incorporation

“…This is mainly due to the fact that glass possesses interesting physical properties and good in ultraviolet protection capacity. On top extraordinary chemical, thermal, structural, and optical properties of glass make them greatly suitable for broad range of applications [3]. However, over prolonged duration the useful properties of glass such as appearance, strength, and chemical stability degrade due to the exposure of various environmental stresses and temperature.…”

mCharacteristics of Carbon Tetrafluoride Plasma Resistance of Various Glasses

“…Also, plasma resistant characteristics have been comparatively evaluated by selecting zinc aluminum phosphate glass based on consideration of plasma resistant characteristics and thermal expansion coefficient, alkali-free aluminosilicate glass, boric acid glass having chemical stability and Y 2 O 3 -containing yttrium aluminosilicate system known to have high plasma resistant characteristics as the glass material to be coated onto the damaged alumina surface. [14][15][16]…”