Although silicone foam and memory foam have different chemical natures, they both have porous structures, so they show some similarities on a macroscopic level.
First of all, the core functions of both are energy absorption and buffering. Their interiors are filled with a large number of tiny holes. When subjected to external pressure or impact, these hole structures will effectively disperse and absorb energy through deformation, thereby playing a role in shock absorption and protection. This feature makes them all widely used in fields that require comfort and safety, such as padding materials, protective gear, packaging, etc.
Secondly, they all belong to lightweight materials. The foaming process significantly reduces its density and makes it very light in weight, which is crucial for applications that require a reduction in overall weight, such as wearable devices, aerospace or transportation vehicles.
Finally, both have certain heat insulation and sound insulation properties. The still air inside the material is a good insulator of heat and sound, so these two types of foams are also often used in situations where heat preservation or noise reduction is required.
Despite the above-mentioned similarities, silicone foam and memory foam are worlds apart in terms of chemical nature and core performance, which determines their completely different application fields.
1. Chemical nature and rebound mechanism: This is the most fundamental difference. Memory foam is a special type of polyurethane (PU), and its molecular chain has unique "viscoelasticity". Its response to external forces is slow and time-dependent. When under pressure, molecular chains move slowly and entangle with each other to absorb energy. After the pressure is removed, they rebound to their original state very slowly, and during this process, part of the energy is dissipated in the form of heat. This is the origin of its "slow rebound" and "temperature-sensing" (softening when heated) characteristics. Silicone foam, on the other hand, is an inorganic-organic hybrid structure composed of stable silicon-oxygen bonds (Si-O). Its rebound is a pure, rapid and efficient elastic deformation, similar to a super spring that never deforms. After the pressure is removed, instantly returns to its original state with almost no energy dissipation, so its compression set is extremely low.
2. Temperature stability and flame retardancy: This is the most significant gap in performance between the two. Silicone foam has extremely excellent heat resistance and can maintain stable performance within a wide range of -60℃ to 250℃ without softening or becoming brittle. It is an excellent flame-retardant material that self-extinguishes when removed from the fire source and is widely used in fields with extremely high fire protection requirements. On the contrary, memory foam has very poor heat resistance. Its characteristics are highly sensitive to temperature. When exposed to heat, it becomes softer (temperature-sensitive). Ordinary memory foam is prone to aging when exposed to an environment above 70℃ for a long time. It is flammable. When burning, it will melt and produce toxic smoke. Flame retardants must be added to meet certain flame retardant standards.
3. Environmental friendliness and durability: Silicone foam is renowned for its chemical inertness, being non-toxic and odorless, and having excellent biocompatibility, which can pass the most stringent medical tests