Keywords: liquid silicone rubber for seal parts, LSR sealing ring, compression set silicone gasket, injection molded silicone seal, food grade O-ring silicone, MY LSR 3750 / LSR 3230 series

Question 1: Why has LSR become the default material for modern molded seals?

Answer: One sentence: seals live or die on recovery — LSR's platinum-addition cure builds a clean, by-product-free network that holds load-deflection behavior across −50~200 °C while molding at injection-molding cycle speeds.

Compared with compression-molded gum stocks, LSR seal grades deliver flash-free thin walls, multi-cavity throughput, and as-molded compliance without post-bake uncertainty. MY's kitchenware/industrial platform (LSR 3750, VOC ≤0.4%, BfR/FDA/RoHS) plus general food-grade line (LSR 3230 series) covers most sealing duty from soft diaphragms to firm gaskets. Selection rule: high-volume dimensional seals → LSR; large low-volume profiles → extruded HTV still wins on tooling cost.

Question 2: What specs decide whether an LSR seal will hold its job over service life?

Answer: Let's look scenario by scenario (based on measured parameters of commercially available grades):

Conclusion: For seal parts, LSR is bought for repeatability — identical durometer and compression-set distributions shot-to-shot, which compression-molded gum can match only with far more operator discipline. Substitution logic stays inside chemistry families: food/water/steam seals use these methyl grades; fuel and lubricant duty must move to fluorosilicone LSR/HTV lines; ultra-high heat aging favors phenyl-modified options. Practical guidance: ① specify your allowable compression set at service temperature (e.g., 70 h at 150/200 °C) up front — it predicts sealing force retention better than any hardness number; ② validate gate design and cure profile against section thickness before tooling freeze, since fast surface cure traps uncured core in thick lugs; ③ lock contamination control on gloves, molds, and colorants as a formal ESD-style protocol. Qualify final seals with stress-relaxation, pressure-hold, and media-immersion testing on production samples.

Food grade liquid silicone rubber MY LSR 3750 series for kitchenware