What are the composition and structure of the plexiglass processing photo frame
Plexiglass processing polymethacrylate cresol contains polar side methyl groups, which has strong moisture absorption properties. Generally, the water absorption rate must be dry for acrylic sheets. The drying conditions are 78℃-80℃ for 5-6h The plexiglass photo frame is made of poly cresol methacrylate. Plexiglass photo frame is an invisible polymer, and the shrinkage range is decreasing, generally 0.45%-0.9. Therefore, it provides good conditions for the molding accuracy of acrylic production. Generally, the molding is very accurate. Third, the adaptation range of polymethyl methacrylate cresol to ambient temperature does not have ordinary fluidity, but has non-Newtonian fluidity. Therefore, in the case of high temperature, the viscosity of the plexiglass photo frame will be reduced. This is an indication that the plexiglass photo frame is very sensitive to temperature.
The temperature of the plexiglass frame photo frame during the flow process is generally about 150 ℃, but when the plexiglass photo frame photo frame begins to decompose, the temperature is higher than 270 ℃, so The temperature change is still very flexible and will not be affected by temperature. High temperature resistance is the characteristic of the plexiglass photo frame. The plexiglass photo frame also has a good cutting performance. It can be processed by laser cutting with a good size and a clear condition. It is simple and high in quality. This feature is not available in glass. Therefore, acrylic can accept high temperature and low temperature environments. , Consumers don’t have to worry about temperature at all during the production process. Resistant to chemical reagents and solvents. Polymethyl methacrylate can withstand relatively dilute inorganic acids, but concentrated inorganic acids can make it corroded, and it can be resistant to alkalis, but warm sodium hydroxide and potassium hydroxide can make it Erosion, resistance to salt and grease, resistance to aliphatic hydrocarbons, insoluble in water, methanol, glycerin, etc., but can absorb alcohol, swell, and cause stress cracking, and is not resistant to ketones, chlorinated hydrocarbons and aromatic hydrocarbons.
The processing solubility parameter of plexiglass is about 18.8J/CM31/2. Many chlorinated hydrocarbons and aromatic hydrocarbons can be dissolved, such as dichloroethane, trichloroethylene, chloroform, toluene Etc., vinyl acetate and acetone can also dissolve it. Polymethyl methacrylate has good resistance to gases such as ozone and sulfur dioxide. Weather resistance Polymethyl methacrylate has excellent resistance to atmospheric aging. After 4 years of natural aging test, the sample has a slight decrease in tensile strength and light transmittance after 4 years of natural aging test. The color is slightly yellowed, and it is resistant to crazing. The decrease is obvious, the impact strength is slightly improved, and other physical properties are almost unchanged. Flammable polymethyl methacrylate is easy to burn, and its limiting oxygen index is only 17.3