The differences between LSR & ordinary rubber
Liquid silicone rubber (LSR) and conventional rubber differ significantly in several aspects, including chemical structure, performance characteristics, application areas, and cost. Here's a detailed comparison:
1. Chemical Structure
Liquid Silicone Rubber (LSR): Primarily composed of silicon (Si) and oxygen (O) elements, with siloxane bonds (Si-O-Si) dominating the molecular chain. This structure imparts unique physical and chemical properties to LSR. Additionally, LSR may contain other functional groups, such as vinyl or Si-H bonds, to facilitate specific crosslinking reactions and functionalities.
Conventional Rubber: Typically refers to polymers based on natural or synthetic rubber, with molecular chains primarily consisting of carbon (C) and hydrogen (H) elements, and often containing unsaturated bonds (like C=C double bonds). The main polymer backbone of conventional rubber is a -C-C- chain, which is markedly different from the siloxane bond structure of LSR.
2. Performance Characteristics
Temperature Resistance: LSR exhibits excellent resistance to both high and low temperatures, maintaining stable physical and chemical properties across a wide temperature range. In contrast, conventional rubber has a narrower temperature tolerance and tends to degrade or age quickly under high temperatures.
Weather Resistance: LSR has outstanding weather resistance, effectively resisting the degradation caused by UV rays, ozone, and other environmental factors. Conventional rubber, on the other hand, has relatively poor weather resistance and is more prone to aging due to environmental exposure.
Elasticity and Resilience: LSR offers high elasticity and excellent resilience, allowing it to quickly return to its original shape after being subjected to external forces. While conventional rubber also has some degree of elasticity, its resilience may not match that of LSR.
Chemical Stability: LSR has good chemical stability, resisting corrosion from various acids, bases, and organic solvents. Conventional rubber may swell, dissolve, or undergo crosslinking when exposed to certain chemical environments.
Biocompatibility: LSR is highly biocompatible with human tissue, not causing rejection or allergic reactions, making it valuable in the medical and healthcare sectors. Conventional rubber, in contrast, has relatively lower biocompatibility.
3. Application Areas
Liquid Silicone Rubber (LSR): Due to its unique physical and chemical properties, LSR is widely used in various fields. For instance, it is used in the electronics and electrical industries for making keypads and seals, in the healthcare industry for producing baby bottle nipples and medical devices, and in the automotive industry for making gaskets and vibration-damping layers.
Conventional Rubber: While conventional rubber is also widely used, its applications are generally in areas where the material's performance requirements are not as stringent. Examples include tires, hoses, and adhesive tapes.
4. Cost
Generally, the production cost of LSR is higher than that of conventional rubber. This is mainly due to the higher cost of raw materials, the more complex production processes, and the higher performance demands in its applications. However, with ongoing technological advancements and cost reductions, the cost-effectiveness of LSR is steadily improving.