Cracking the Code of Silicone Hardness
Silicone hardness is not a static property but rather a result of several dynamic factors spanning from the raw material composition to the molding process. Below, we delve into these pivotal components shaping silicone hardness:
Composition:
Silicone's chemical makeup, including elements like silicon, oxygen, carbon, and hydrogen, lays the foundation for its hardness. Manipulating silicone hardness involves precise control over raw material formulations. Additives like silicone resin, silicone oil, ethylene, and colloidal silica alter the chemical structure and crystallinity, demanding expert finesse to achieve desired results.
Curing Time:
The curing process, occurring either at ambient temperature or through heat application, plays a crucial role in determining silicone hardness. By adjusting curing time and temperature, manufacturers can finely tune the hardness of silicone products to meet specific requirements.
Crosslinking Density:
Crosslinking density refers to the tightness of chemical bonds within silicone material, akin to a molecular network. The denser the network, the harder the silicone. Factors such as heating temperature, duration, and pressure during manufacturing influence crosslinking density, offering avenues for tailoring silicone hardness.
Additives:
Additives wield significant influence during silicone molding, particularly in vulcanization processes. These compounds stabilize molecular structures, enhance hardness, and augment various silicone properties. With a spectrum of additives available—ranging from fillers and vulcanizing agents to modifiers and structure controllers—meticulous adjustment of proportions enables precise modulation of silicone hardness.
Measuring Silicone Hardness:
Silicone hardness evaluation typically employs hardness testers, with two prevalent standards:
Shore Hardness: Utilizing a probe and spring device, Shore hardness testing involves measuring the depth of probe penetration into the material under specific spring force. The resulting value indicates silicone hardness, with Type A and Type D variants catering to different material hardness ranges.
International Rubber Hardness Degrees (IRHD): IRHD employs a steel ball pressed onto the material to ascertain hardness based on indentation depth. Categorized into Micro, Low, Normal, and Hard, IRHD offers nuanced hardness assessment across various material types.
Understanding these factors and employing precise measurement techniques ensures optimal control and customization of silicone hardness to meet diverse application needs.
Ray Xian
Phone/Whatsapp: +8619902910431
Email/Skype: ray.x@siliconesupplier.com
