Glass steel has been widely used in many spheres due to its high performance.Glass steel has been widely used in the food industry in countries such as the United States, the United Kingdom, Italy, and Japan for the manufacture of containers for brewing industry, high-level water tanks, milk containers, microwave discs, mounting coolers, etc. However, the polyester resin and glass steel used in the country's food industry are in the stage development and regulatory and supervisory issues have yet to be resolved, so their effective implementation will give a strong boost to our glass and steel industry.
Glass and steel products used in the food industry are generally in contact with food and the presence of hazardous substances in glass products will directly affect human health and safety. Therefore, it is necessary first of all to rationally select raw materials to produce&"food grade GG" resins, and in the process of forming steel glass products, apply a rigorous technological system and technical measures to ensure that glass products meet the requirements of safety, hygiene and no bacteriological infection.
Requirements and selection of raw materials
In order to ensure that chemicals and hazardous substances in glass and steel products are not diverted into rich foods for degradation, the raw materials used in resin production must be rigorously selected, which is a prerequisite for ensuring that the resin meets the requirements of&"food grade GG".
In theory, the reaction of the double keys of the phenylacetic monolithic polyester resin by decomposition of peroxides, which occurs as a catalyst agent, in the phenylene monobutyl polyester polyester resin is converted into a large, insoluble molecular structure, of stable and non-toxic nature.But influenced by the purity of raw materials, it contains unwanted impurities.In addition, as the cascade reaction of the system proceeds, the molecular mass increases and the viscosity of the system increases, especially when the temperature environment solidifies, the response is not complete, so in glass steel with polyester ester there are still small amounts of insulators and phenylacetic monomers, with some residues of low toxicity substances. This is the main source of toxicity of the polyester glass steel.
Post-solidification is the ideal method to achieve a complete reaction in the polyester molecular chains and the styrene transition, as well as to optimize the physical and chemical properties of the products. Post-solidification temperature is normally 24 hours at room temperature (20 ° C), followed by a temperature of 80 to 100 ° C and a solidification of 8 hours. Styrene residues on glass steel were 0.3,0.5%. In addition, it must be treated for two hours with steam before be used, that is, for more than two hours in a detergent solution of 80 ° C and 1% and then in potable water. In this way, styrene residues could be reduced to 0.1% .Reprocessing of the Solidification and cleaning of steel glass products is an essential process, according to the FDA regulations of the United States and the Italian Association for Food Sciences.