Validation of an Image Analysis Method for Evaluating the Chemical Resistance of Glass Fibers to Alkaline Environments.

Martina Ryvolová,Lucie Svobodová,Totka Bakalova

doi:10.3390/ma15010161

Abstract

This article is focused on the comparison of the reliability of the results obtained by image analysis (newly proposed evaluation method) with well-known methods of evaluation of long-term corrosion resistance of glass fibers in an alkaline environment (pH > 12). The developed method is based on the analysis of scanning electron microscopy images (diameter and structures on the fiber surface). An experiment (52 weeks) was performed to evaluate two types of glass fibers: anticorrosive glass fibers (ARGFs) and E-glass fibers (EGFs). Three media were used to treat the fibers (23 ± 2 °C): H2O, Ca(OH)2, and K2SiO3. The ARGFs’ tensile strength did not reduce; a decrease by 68% was observed for EGFs in H2O. Tensile strength decreased by 32% and 85–95% in K2SiO3; by 50% and 64% in Ca(OH)2 for the ARGF and EGF, respectively. Statistical analysis was performed to validate the reliability and plausibility of the developed method. ARGFs and EGFs did not show any relationship between the fiber diameter and weight in H2O; however, the linear trends may predict this relationship in Ca(OH)2 and K2SiO3. For the ARGF and EGF, the cubic trend was suitable for predicting the change in fiber weight and diameter over time in Ca(OH)2 and K2SiO3.

Highlights

Mineral fibers include a range of glass and basalt fibers, and they have good mechanical properties such as high tensile strength, high tensile modulus, non-flammability, dimensional stability, and good resistance to heat, fungi, and microorganisms
(Figure 1a), the tensile strength of the anticorrosive glass fibers (ARGFs) increased by 32% compared with the reference sample after W2
For the E-glass fibers (EGFs) in H2 O (Figure 9a), only the linear trend may predict the changes in the fiber weight and diameter over time. These results show that the ARGFs lost weight at a rate about eight times slower than EGFs, and the diameter increased at a rate about seven times slower than EGFs

Summary

Introduction

Mineral fibers include a range of glass and basalt fibers, and they have good mechanical properties such as high tensile strength, high tensile modulus, non-flammability, dimensional stability, and good resistance to heat, fungi, and microorganisms. They are commonly used as reinforcement or dispersed in composites where the matrix material has low tensile strength, such as polymers, ceramics, concrete, and aluminosilicate mixtures. The chemical resistance of glass and basalt fibers varies according to the fiber composition (elements/oxides), temperature, solution concentration, and exposure time

Methods

Results

Conclusion