The current domestic and foreign common material is LSR (Liquid Silicone Rubber), Chinese translation: liquid silicone. Liquid silicone is a relatively solid high-temperature vulcanized silicone rubber. It is a liquid adhesive that has good fluidity, fast vulcanization, and is safer and more environmentally friendly. It can fully meet food-grade requirements. According to the structure of the functional groups (ie cross-linking points) contained in the molecular structure, liquid rubbers with functional groups are often divided into two categories: one is that the functional groups are at the two ends of the molecular structure called telechelic liquid rubber; the other is The reactive functional groups are randomly distributed in the main chain, that is, so-called functional groups within the molecular structure, and are called non-telechelically-type liquid rubbers.