What Are The Cosmetic Properties of Fiberglass? （part 1）

  Usually glass fibers have a smooth cylindrical appearance with a complete circular cross-section. This is due to the fiber forming process, molten glass is drawn and cooled into a solid state before the fiber, under the action of surface tension contraction into the smallest surface area due to round. It differs from organic fibers, which have a non-circular surface structure due to deeper wrinkles on the surface. Microscopic observation of the glass fiber and other organic fiber shape differences. The surface of glass fibers is smooth, so the holding force between fibers is very small, which affects the composite effect with resin. The smooth surface, however, offers little resistance to the passage of gases and liquids, making it ideal for making filtration materials.

  The density of glass fibers is higher than organic fibers, but lower than most metals, roughly similar to aluminum glass fiber density is generally in the 2.50 ~ 2.70g/cm' or so, mainly depends on the glass composition. Certain special glass fibers, such as quartz glass fibers, high silica glass fibers and low dielectric glass fibers, etc., their density is even lower, only 2.0-2.2g/m', and contains a large number of heavy metal oxides of high-modulus glass fibers density of up to 2.70 ~ 2.90g/cm'. The density of glass fibers is lower than that of block glass of the same composition.The results of W. Otto and F. Preston show that the density of aluminum borosilicate glass fibers is 2.52g/cm', while the density of block glass of the same composition is 2.58g/m, which is 2.35% smaller. This is due to the fact that the glass fiber retains the structural state of the high temperature glass liquid, while the block glass tends to be densely arranged molecules during the cooling and annealing process, so it has a higher density value compared to the fiber.

  The strength of glass fiber is not only to be higher than the block glass strength of several 10 times, but also far more than other natural fibers, synthetic fibers and a variety of alloy materials, so it is the ideal reinforcing material, the impact of glass fiber strength of the factors are also many. Glass composition is different, with their made of fiber strength is also different, NazO-CaO-SiO, the system of C glass 5 # fiber strength is the lowest, CaO-AlzO: - Si0, the system of E glass fibers in the middle, and MgO-AzO: - Si0, the system of S glass fibers is the highest. This may be related to the structure of the glass, which is composed of MgO, AlO3, and SiO: with a compact structure, and therefore has the highest strength.

  One of the main uses of e-glass fiber is in the electrical industry as a variety of electrical insulating materials, radome wave-transparent materials and so on. This is because it has good electrical insulation properties and dielectric properties. At the beginning of the glass fiber is for the use of electrical insulation and development. China's alkali-free glass also belongs to the E glass series, at room temperature, its volume resistivity and surface resistivity are greater than 101Ω-cm, at a frequency of 10Hz when the dielectric loss angle tg8 is 1.1x10-3, dielectric constant e is 6.6.

  The chemical stability of glass fiber refers to its resistance to water, acid, alkali and other media erosion. Usually by the media before and after the erosion of weight loss, precipitation of alkali and into the erosion of the amount of glass composition in the liquid, the erosion of the loss of strength and fiber diameter reduction rate and other indicators to measure. On the chemical stability of glass, there has been a lot of research, no less than thousands of monographs in this area. Glass fibers and the same species of glass, compared with a large surface area, and therefore more intense erosion by the medium, but in terms of its erosion mechanism is the same as glass.