How to check the quality of silicone products?

How to check the quality of silicone products? Due to their unique physical and chemical properties, silicone products are widely used in various fields such as medical, maternal and child care, kitchen, electronics, and industry. However, the quality of silicone products in the market varies greatly, and how to scientifically check their quality has become a focus of consumer attention. This article will systematically analyze the quality inspection methods of silicone products from four dimensions: appearance, physical properties, chemical safety, and adaptability to usage scenarios, combined with industry testing standards and daily practical skills.

Appearance inspection: intuitive judgment of basic quality
Appearance is the first threshold for the quality of silicone products. The surface of high-quality silicone products should be smooth and flat, without defects such as bubbles, cracks, missing glue, impurities, etc. For example, food grade silicone tableware needs to be visually inspected for uniform color and clear and firm printing patterns to avoid health risks caused by pigment migration.
In the medical field, the appearance inspection of silicone sealing rings is more stringent. It is necessary to use a magnifying glass or microscope to inspect the surface for burrs and burrs, as these small defects may affect the sealing performance and cause liquid or gas leakage. In addition, the dimensional accuracy of silicone products also needs to be measured using tools such as calipers and micrometers to ensure that the error with the design requirements is within the allowable range.

Physical performance testing: quantitative evaluation of core indicators
The physical properties of silicone directly determine its applicable scenarios and service life.
Hardness testing: Measure the hardness value (Shore A) of silicone gel using a Shore hardness tester, with different hardness ranges corresponding to different applications. For example, kitchen silicone shovels need to be soft and heat-resistant (with a hardness of about 30-40A), while sealing rings need to have a higher hardness (50-70A) to ensure sealing.
Tensile and tear strength: The tensile strength of high-quality silicone should be ≥ 8MPa, and the tear strength should be ≥ 25kN/m. The tear resistance can be tested by stretching the sample to twice its original length, observing whether it quickly rebounds without deformation, or simulating the shear force in actual use.
Temperature resistance: The temperature range of silicone is usually -40 ℃ to 230 ℃. You can observe its flexibility by boiling it in boiling water for 30 minutes or freezing it for 24 hours. High quality silicone should be kept without deformation or brittleness.
Wear resistance: For high-frequency usage scenarios (such as silicone phone cases), friction testing can be used to simulate daily wear and observe whether there are scratches or discoloration on the surface.

Chemical safety testing: strict control of health risks
The chemical safety of silicone products is of utmost importance in quality inspection, especially for food grade and medical grade products.
Hazardous substance detection: Professional institutions need to be used to detect whether silicone contains harmful substances such as heavy metals (such as lead and cadmium), plasticizers (such as phthalates), bisphenol A (BPA), etc. For example, the VOC (volatile organic compound) content of food grade silicone should be less than 0.5% and certified by international organizations such as FDA and LFGB.
Migration substance test: Soak silicone products in a specific solvent (such as simulated gastric acid solution) to detect the precipitation of harmful substances. This test is particularly important for products that come into direct contact with food, such as baby pacifiers and tableware.
Odor and combustion test: High quality silicone has only a slight raw material odor and no pungent chemical odor. When burning, white smoke should be emitted, and the residue is white powder; If combustion produces black smoke or irritating odors, it may contain inferior additives.

Application scenario adaptation detection: precise matching of functional requirements
The quality of silicone products needs to be comprehensively evaluated based on specific usage scenarios.
Sealing performance: For products such as sealing rings and bottle caps, their sealing effect can be tested by water or air pressure testing. For example, install the silicone seal ring on the container and apply pressure to observe for any leakage.
Anti slip performance: For silicone foot mats, anti slip pads and other products, their anti slip coefficient can be measured by sliding tests on different material surfaces (such as glass, wood).
Biocompatibility: Medical grade silicone gel needs to undergo biocompatibility tests such as cell culture and skin irritation testing to ensure that it is non-toxic and harmless when in contact with the human body.
Aging resistance: Simulate long-term outdoor use environment through ultraviolet aging test to observe whether silicone products change color, become brittle or have decreased performance.