{"id":1823,"date":"2026-04-21T06:05:58","date_gmt":"2026-04-21T06:05:58","guid":{"rendered":"https:\/\/meitu-engelhardt.com\/?p=1823"},"modified":"2026-04-21T06:05:58","modified_gmt":"2026-04-21T06:05:58","slug":"lsr-vs-tpe","status":"publish","type":"post","link":"https:\/\/meitu-engelhardt.com\/de\/lsr-vs-tpe\/","title":{"rendered":"LSR vs. TPE: Wann sollte man Silikon gegen\u00fcber thermoplastischen Elastomeren w\u00e4hlen"},"content":{"rendered":"
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LSR vs TPE is the elastomer-selection question that dooms most product teams before a single part is tooled. Both liquid silicone rubber (LSR) and thermoplastic elastomer (TPE) displace natural rubber in the most demanding precision applications, yet they occupy opposite extremes of polymer chemistry \u2014 one is a permanently vulcanized thermoset, the other a re-heatable thermoplastic. Choose unwisely and you’ll either be footing 3\u00d7 the tooling bill or watching a precision rubber part creep out of spec in the field. This guide walks through chemistry, temperature, cost, and process factors that drive the pick, then hands you a no-jargon decision rule grounded in production economics \u2014 not supplier marketing.<\/p>\n

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Quick Specs: LSR vs TPE at a Glance<\/h3>\n\n\n\n\n\n\n\n\n\n\n
Polymer class<\/td>\nLSR: thermoset \u00b7 TPE: thermoplastic<\/td>\n<\/tr>\n
Continuous service temp<\/td>\nLSR: \u221260 to +200 \u00b0C \u00b7 TPE: \u221240 to +100 \u00b0C (typical)<\/td>\n<\/tr>\n
Shore hardness range<\/td>\nLSR: Shore A 5\u201380 \u00b7 TPE: Shore OO 20 \u2013 Shore A 95<\/td>\n<\/tr>\n
Molding tolerance<\/td>\nLSR: \u00b10.025\u20130.05 mm \u00b7 TPE: \u00b10.05\u20130.10 mm<\/td>\n<\/tr>\n
Cycle time<\/td>\nLSR: 30\u201390 s \u00b7 TPE: 15\u201340 s<\/td>\n<\/tr>\n
Recyclable?<\/td>\nLSR: No (crosslinked) \u00b7 TPE: Yes (regrind accepted)<\/td>\n<\/tr>\n
Tooling cost<\/td>\nLSR: $15K\u2013$80K \u00b7 TPE: $10K\u2013$50K<\/td>\n<\/tr>\n
Volume fit<\/td>\nLSR: 10,000+ parts\/yr \u00b7 TPE: 5,000+ parts\/yr<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

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What Are LSR and TPE? \u2014 Thermoset vs Thermoplastic in One Chart<\/h2>\n

\"What<\/p>\n

Decide the chemistry first. The thermoplastic elastomer vs silicone comparison rests on how each polymer responds to heat. Silicone-based LSR is a thermoset: heating a two-part liquid silicone through a platinum catalyst drives an irreversible cross-linking reaction \u2014 a vulcanization process that locks molecules into a permanent elastic network. Once cured, the part will not soften again \u2014 even at 250 \u00b0C it stays rubbery rather than melting.<\/p>\n

TPE runs the opposite way. It is a copolymer that melts when heated, fills the mold, and hardens on cooling \u2014 no chemistry change. Reheat the part and it turns liquid again, which is why TPE scrap can be reground and reused like any thermoplastic.<\/p>\n

What Is the Difference Between TPE and LSR?<\/h3>\n

Short answer: LSR crosslinks permanently under heat (thermoset), while TPE softens and re-hardens repeatedly (thermoplastic). That single chemistry difference cascades into every downstream decision \u2014 temperature ceiling, recyclability, tooling cost, cycle time, and which sterilization methods the part can survive. TPE covers seven commercially important families: styrenic block copolymers (SBS and hydrogenated SEBS), thermoplastic vulcanizates (TPV), thermoplastic polyurethane (TPU), thermoplastic polyolefin (TPO), copolyester elastomers (COPE), and copolyamide elastomers (COPA). According to the British Plastics Federation plastipedia<\/a>, the specific family selected drives roughly 80 % of the final mechanical behavior. LSR, by contrast, is a single-chemistry material varied mainly by durometer grade and filler package.<\/p>\n

For manufacturers realistically evaluating both materials on a given program, our LSR injection molding services<\/a> team runs side-by-side DFM reviews to flag the crossover point where either material makes rational sense.<\/p>\n

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Material Properties Compared: TPE vs Silicone Rubber Head-to-Head<\/h2>\n

\"Material<\/p>\n

Once the decision moves from concept to specification, five properties determine the eventual tpe vs silicone rubber outcome: temperature limits, hardness range, tear strength, chemical compatibility, and compression-set recovery. A comparison table below summarizes values cross-referenced from Avient’s material knowledge base, the BPF plastipedia<\/a>, and ASTM D2240 durometer standards.<\/p>\n

\n\n\n\n\n\n\n\n\n\n\n\n\n
Property<\/th>\nLSR<\/th>\nTPE<\/th>\n<\/tr>\n<\/thead>\n
Continuous temp range<\/td>\n\u221260 to +200 \u00b0C<\/td>\n\u221240 to +100 \u00b0C (grade-dependent)<\/td>\n<\/tr>\n
Shore hardness<\/td>\nA 5 \u2013 A 80<\/td>\nOO 20 \u2013 A 95<\/td>\n<\/tr>\n
Specific gravity<\/td>\n~1.12<\/td>\n~0.89<\/td>\n<\/tr>\n
Elongation at break<\/td>\nUp to 950 %<\/td>\nUp to 700 % (SEBS grades)<\/td>\n<\/tr>\n
Tear strength<\/td>\nRelatively low \u2014 small tears propagate<\/td>\nFormulable to film-level 3-mil stretch<\/td>\n<\/tr>\n
Compression set (22 h @ 100 \u00b0C)<\/td>\n10\u201325 %<\/td>\n25\u201355 %<\/td>\n<\/tr>\n
UV\/ozone resistance<\/td>\nInherent (no additives)<\/td>\nAdditive-dependent<\/td>\n<\/tr>\n
Biocompatibility<\/td>\nInherent (platinum-cured)<\/td>\nGrade-dependent (medical TPE available)<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

Is LSR an Elastomer?<\/h3>\n

Yes \u2014 LSR is an elastomer, but a thermoset one. An elastomer is any polymer that recovers elastically after deformation, and LSR’s platinum-cured network hits that behavior across its full service temperature window. Where it falters is tear propagation: once a crack initiates in LSR, it tends to run.<\/p>\n

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“Although fillers may improve properties somewhat, tear and tensile strengths remain relatively low [in LSR]. Even a small tear can lead to catastrophic failure.”<\/p>\n