{"id":1242,"date":"2026-04-03T08:05:11","date_gmt":"2026-04-03T08:05:11","guid":{"rendered":"https:\/\/meitu-engelhardt.com\/?p=1242"},"modified":"2026-04-03T08:19:34","modified_gmt":"2026-04-03T08:19:34","slug":"silicone-vs-rubber","status":"publish","type":"post","link":"https:\/\/meitu-engelhardt.com\/pt-br\/silicone-vs-rubber\/","title":{"rendered":"Silicone vs Borracha: principais diferen\u00e7as para engenheiros e equipes de compras"},"content":{"rendered":"
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Silicone vs Rubber: Key Differences for Engineers & Procurement Teams<\/strong><\/p>\n

Engineers and procurement professionals encounter the silicone vs rubber dilemma every time a new sealing, gasket, or flexible component specification hits the books. Both materials are elastomers, meaning they deform under stress then return to their original shape, but they have radically different performance profiles in terms of temperature, chemical compatibility, longevity, and economics. Choose unwisely, and you’ll face expensive early part failures or a costly material rebuild.<\/p>\n

This primer explains the true distinctions between silicone and rubber on a line-by-line basis. Every property is backed up with standard specification data as well as guidance based on decades of manufacturing experience, enabling you to identify the best material for your application without conjecture.<\/p>\n

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In This Guide<\/strong><\/p>\n

    \n
  1. What’s the difference between silicone and rubber?<\/li>\n
  2. Property-by-Property Comparison<\/a><\/li>\n
  3. When should I choose silicone over rubber?<\/li>\n
  4. Industry Applications<\/a><\/li>\n
  5. Cost, Lifespan, and Total Value<\/a><\/li>\n
  6. How Compression Molding Produces Both<\/a><\/li>\n
  7. FAQ<\/a><\/li>\n<\/ol>\n<\/div>\n

    <\/p>\n

    What Is Silicone and What Is Rubber?<\/a> Clearing Up the Confusion<\/h2>\n

    \"What<\/p>\n

    What is a silicone rubber? Although “silicone” is often used as a synonym for “silicone rubber,” the two materials are not identical. Silicone rubber is a type of elastomer\u2014a member of the same class of materials as rubber\u2014that is made of synthetic polymers with silicon-oxygen as its fundamental component. This gives silicone rubber different properties than rubber derived from natural sources. Historically, the term “rubber” was first applied to natural latex and polyisoprene, which are derived from the sap of rubber trees. Over time, the term has come to encompass synthetic variants as well.<\/p>\n

    Natural rubber is obtained by collecting latex sap from Hevea brasiliensis trees. This juice is then refined into polyisoprene, a naturally occurring polymer based on carbon and hydrogen -carbon-hydrogen carbon-hydrogen chains. Since the dawn of manufacturing, this material has been used extensively and, as a result, remains a common elastomer.<\/p>\n

    Silicones are a class of man-made polymers composed primarily of silicon and oxygen -silicon-oxygen -silicon-oxygen -chain, also known as a polysiloxane or siloxane. Because of the silicon-oxygen backbone, silicones demonstrate one of the broadest ranges of chemical inertness and thermal stability. It’s important to recognize the distinction: silicon is a chemical element represented as Si with atomic number 14. Silicone describes the synthetic polymer that includes silicon among its composition.<\/p>\n

    What is a type of synthetic rubber? An umbrella term for rubbers derived from petrochemical sources, these include styrene-butadiene rubber (SBR), nitrile, ethylene-propylene-diene monomer (EPDM), and neoprene. Every variation is formulated to achieve intended properties like oil or weather resistance.<\/p>\n

    \n\n\n\n\n\n\n\n\n
    Feature<\/th>\nNatural Rubber<\/th>\nSilicone Rubber<\/th>\nSynthetic Rubber (general)<\/th>\n<\/tr>\n<\/thead>\n
    Origin<\/td>\nRubber trees (latex)<\/td>\nSynthetic (siloxane polymer)<\/td>\nPetroleum-derived<\/td>\n<\/tr>\n
    Backbone<\/td>\nCarbon\u2013carbon (C\u2013C)<\/td>\nSilicon\u2013oxygen (Si\u2013O)<\/td>\nCarbon\u2013carbon (C\u2013C)<\/td>\n<\/tr>\n
    Classification<\/td>\nNatural or synthetic elastomer<\/td>\nSynthetic elastomer<\/td>\nSynthetic elastomer<\/td>\n<\/tr>\n
    ASTM D2000 Type<\/td>\nAA (NR), BF\/BG (SBR)<\/td>\nFC\/FE\/GE (VMQ)<\/td>\nVaries by compound<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n
    \n
    \ud83d\udca1<\/span> Pro Tip<\/strong><\/div>\n

    Occasionally, the job of specification writer is tainted by a simple typo\u2014”silicon” mistakenly written where “silicone” should be. While many scientists know the obvious departure between a metalloid element and flexible polymer, the resulting confusion may lead to ordering the wrong part.<\/p>\n<\/div>\n

    <\/p>\n

    Silicone vs Rubber \u2014 Property-by-Property Comparison<\/h2>\n

    In most circumstances, the real distinction between silicone and rubber is revealed when the material’s measurable engineering data is presented side by side. Below is a collection of the most relevant specifications influencing component selection for gasketing, sealing, and flexible assemblies.<\/p>\n

    \n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
    Property<\/th>\nSilicone (VMQ)<\/th>\nNatural Rubber (NR)<\/th>\nEPDM<\/th>\n<\/tr>\n<\/thead>\n
    Temperature Range<\/td>\n-60\u00b0C to +230\u00b0C<\/td>\n-30\u00b0C to +80\u00b0C<\/td>\n-50\u00b0C to +150\u00b0C<\/td>\n<\/tr>\n
    Tensile Strength<\/td>\n5\u201312 MPa<\/td>\n20\u201330 MPa<\/td>\n7\u201321 MPa<\/td>\n<\/tr>\n
    Tear Resistance<\/td>\nLow\u2013moderate (10\u201350 kN\/m)<\/td>\nHigh (80\u2013120 kN\/m)<\/td>\nModerate (20\u201340 kN\/m)<\/td>\n<\/tr>\n
    Hardness (Shore A)<\/td>\n10\u201380<\/td>\n30\u201390<\/td>\n30\u201390<\/td>\n<\/tr>\n
    UV \/ Ozone Resistance<\/td>\nExcellent<\/td>\nPoor (degrades)<\/td>\nExcellent<\/td>\n<\/tr>\n
    Chemical Resistance<\/td>\nGood (acids, bases); poor with oils\/fuels<\/td>\nPoor (oils, solvents, ozone)<\/td>\nGood (water, steam, glycols); poor with oils<\/td>\n<\/tr>\n
    Oil \/ Fuel Resistance<\/td>\nPoor (swells)<\/td>\nPoor<\/td>\nPoor (use nitrile instead)<\/td>\n<\/tr>\n
    Electrical Insulation<\/td>\nExcellent (insulating properties)<\/td>\nGood<\/td>\nGood<\/td>\n<\/tr>\n
    Compression Set<\/td>\nLow (retains seal over time)<\/td>\nModerate<\/td>\nLow\u2013moderate<\/td>\n<\/tr>\n
    FDA \/ Food Contact<\/td>\nYes (food-grade, odorless, non-toxic)<\/td>\nLimited<\/td>\nSome grades<\/td>\n<\/tr>\n
    Approx. Cost ($\/kg)<\/td>\n$5\u2013$50 (grade-dependent)<\/td>\n$1.50\u2013$2.50<\/td>\n$2.50\u2013$3.00<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

    Data sourced from Shin-Etsu Silicone technical datasheets<\/a> and the ASTM D2000 classification system<\/a> for automobiles.<\/p>\n

    A clear pattern emerges from these numbers. In order of performance capability, silicone is high in heat endurance, UV and ozone performance, compression set, and neutral in food and medical compliance. Conversely, natural rubber is stronger in terms of tensile strength, tear strength, resilience, and raw materials cost. Neither would be suitable in petroleum environments\u2014in that case, NBR or FKM would take the assignment.<\/p>\n

    Based on our experience with silicone and organic rubber compounds we encounter the largest performance difference under operating conditions at the temperature extremes. An organic rubber gasket that performs well at 60 C, will fracture and lose its seal above 100 C, whereas a silicone gasket will withstand 200 C without deformation or hardening.<\/p>\n

    \u2014 Engelhardt Engineering Team<\/cite><\/p><\/blockquote>\n

    <\/p>\n

    When to Choose Silicone Over Rubber<\/a> (and Vice Versa)<\/h2>\n

    \"When<\/p>\n

    Selecting the appropriate material involves considering how well the elastomer is suited to its real-world application; not necessarily choosing the lowest or highest cost material. Here is a decision framework based on typical application situations.<\/p>\n

    Choose Silicone When:<\/h3>\n