Three reasons that affect the unqualified hygiene and safety testing of exported silicone products
The hygiene and safety of exported silicone products are highly valued by European and American countries, and it has been found multiple times this year that the pre inspection and sampling of exported silicone products are not qualified. The hygiene indicators of exported silicone products are not up to standard, and we need to address the following three reasons and make improvements
Poor quality control of raw materials. Some factories do not pay enough attention to the raw materials used for kitchen utensils. They use silicone materials with low quality levels for food tool products without testing the raw materials, or use unqualified color adhesives and additives for coloring during the production process, resulting in substandard product hygiene.
The production process is not standardized. Due to the special safety requirements of silicone tableware, food silicone products have very strict production process requirements. After the product is formed, sufficient time is required to remove volatile substances. Some factories have not achieved sufficient processing time for their products in pursuit of efficiency
The company's product usage conditions are not satisfactory. The European Union and other countries require product testing to be carried out in accordance with their foreseeable strictest usage methods. Most factories only produce based on customer samples, without understanding the purpose and usage conditions of the products. They are also relatively blind when dealing with third-party testing, and even have obvious inconsistencies with the foreseeable usage conditions of the products.
Secondary vulcanization of silicone products
Secondary vulcanization is also known as post vulcanization. The effect of secondary vulcanization: When silicone rubber is vulcanized with peroxide, the decomposition of peroxide triggers a polymer reaction, resulting in the formation of low molecular compounds (such as benzene and benzoic acid) that exist in the rubber and affect the mechanical properties of the rubber. In addition, the crosslinking density of silicone rubber is not enough after the first stage of heating molding, and the density of silicone rubber can only be increased by further vulcanization The tensile strength, resilience, hardness, swelling degree, density, and thermal stability are all greatly improved compared to primary vulcanization. If secondary vulcanization is not carried out, the performance of the produced silicone may be affected to some extent, and better performance products cannot be obtained. The parameters of primary vulcanization and secondary vulcanization may be different, which is related to actual operation! There are various types of silicone vulcanization, including high temperature and room temperature. Taking high-temperature silicone as an example, before vulcanization, it is commonly referred to as raw rubber. Blending rubber is the process of refining many additives such as vulcanizing agents, release agents, etc. with raw rubber. It can be seen from the appearance. It breaks easily when pulled by hand, without elasticity. If the mixed adhesive is vulcanized and formed at a certain temperature, a product can be obtained, such as the silicone phone case we usually see. As for whether it is toxic or not, as long as the manufacturer can provide food certification, it is generally non-toxic.
Silica gel is a kind of amorphous silicon dioxide, and the dust content in the workshop should be controlled to be no more than 10 mg/m3. Air exhaust should be strengthened, and masks should be worn during operation.
The superior performance, coupled with the fact that silicone is a non petroleum product and does not rely on increasingly scarce petroleum resources, has made silicone products a substitute for similar plastic products.
Ratio of silicone vulcanizing agent. Silicone rubber is the most common two component vulcanized silicone rubber.
Viscosity. Explanation of technological terms: The volume characteristic of a liquid, quasi liquid, or quasi solid substance that resists flow, that is, the internal friction or flow resistance between molecules when flowing under external forces. Usually, viscosity is directly proportional to hardness.