Walk into any baby-products store, pick up a silicone nipple, and flip it over: there is a good chance the packaging will say “Platinum-Cured Silicone.” The same applies to medical products such as infusion tubing, respiratory masks, and surgical instrument handles—most of them are made from platinum-cured silicone.

Why are food-grade and medical-grade silicone products so strongly associated with platinum catalysts? This article explains the logic behind it, from safety principles and certification requirements to real-world applications.

1. The Core Reason: Platinum Curing Is “Clean”

As discussed in the previous comparison, the fundamental difference between platinum curing (addition cure) and peroxide curing (free-radical crosslinking) is that platinum curing does not generate small-molecule by-products during the reaction.81622

During peroxide curing, the catalyst decomposes and can produce volatile residues such as benzoic acid, acetone, and tert-butanol. These residues not only create a noticeable “rubber odor,” but more importantly, they may migrate out of the silicone product and into food or human tissue.

In platinum-cured systems, the only reaction product is the crosslinked silicone network itself. There are no small-molecule by-products, no acidic or alkaline residues, and no volatiles that require secondary baking to remove. This means:

No odor: The finished silicone product is virtually odorless.

No leaching: After curing, there is minimal migration of chemicals into food or body fluids.

High purity: The product contains no peroxide decomposition residues, giving it exceptionally high purity.3523

For materials that contact the human body, cleanliness is the basic prerequisite.

2. Food-Grade Silicone: How Platinum Curing Meets Strict Certifications

Major food-contact certification standards

Key global standards for food-contact materials include:

U.S. FDA 21 CFR 177.2600: Covers rubber articles intended for repeated food contact.61417

German LFGB: One of the strictest food-contact material standards in the EU.20

China GB 4806 series: National standards for food-contact materials in China.

EU Regulation 1935/2004/EC: The overarching framework for food-contact materials in Europe.

Why platinum-cured silicone has a certification advantage

Platinum-cured silicone products can meet all of these stringent standards, mainly because:

No harmful migration products. Platinum curing does not generate organic small-molecule by-products, so volatile organic compound (VOC) levels are very low in standard migration tests. Published test data indicate that platinum-cured silicone typically shows VOC migration around 0.02 mg/cm², well below common limits such as 0.5 mg/cm².17

Platinum residues are extremely low and chemically stable. Platinum catalysts are used at ppm levels, and platinum remains in the silicone as a stable complex. FDA-related studies on platinum-cured silicone breast implants indicate that platinum exists mainly as zero-valent platinum (Pt⁰), which differs from more toxic chloroplatinate forms.

No peroxide residues. Peroxide-curing residues, such as 2,4-dichlorobenzoic acid, are one of the biggest obstacles in food-grade certification. Platinum curing avoids this issue entirely.823

Typical applications

Silicone tableware: spoons, bowls, plates, straws

Baking molds: cake molds, chocolate molds, ice trays

Kitchen seals: pressure cooker gaskets, thermos seals

Food packaging:保鲜 lids, food-grade silicone bags

Drinking-water equipment: coffee machine tubing, water dispenser seals

3. Medical-Grade Silicone: Why Platinum Curing Is Often Irreplaceable

Medical-grade silicone places even higher demands than food-grade silicone. Beyond being non-toxic and odorless, it must meet strict biocompatibility requirements—the material must not cause cytotoxicity, skin sensitization, genotoxicity, or other adverse reactions.

Key certification standards

ISO 10993 series: International standard for biological evaluation of medical devices, covering cytotoxicity, sensitization, irritation, genotoxicity, implantation response, and more.1521

USP Class VI: U.S. Pharmacopeia Class VI plastic biological reactivity testing.

GB/T 16886 series: China’s national standard for biological evaluation of medical devices.

Why platinum-cured silicone can meet medical-grade requirements

Excellent biocompatibility. In vitro cytotoxicity tests (ISO 10993-5 MTT method), platinum-cured silicone often achieves cell viability above 90%, well above the 70% pass threshold.215 Skin irritation indices are typically below 0.4, outperforming the 0.8 limit.

Stable performance after repeated sterilization. Medical silicone parts often undergo repeated autoclaving (121°C for 30 minutes). Platinum-cured products have a uniform, dense crosslink network and maintain mechanical properties and elasticity after repeated sterilization. Peroxide-cured products are more prone to yellowing, hardening, and residue release under the same conditions.923

Long-term implantation safety. For implantable devices such as pacemaker encapsulation or artificial joint spacers, the chemical inertness and low migration of platinum-cured silicone are critical safety guarantees.1223

Typical applications

Disposable medical consumables: infusion tubing, drainage tubes, blood-collection tube seals

Implantable devices: pacemaker encapsulation, intraocular lens spacers, CSF shunts

Respiratory equipment: breathing masks, CPAP circuit seals

Surgical instruments: instrument handle overmolding, hemostat pads

Drug delivery: transdermal patch substrates, controlled-release carriers

In vitro diagnostics: microfluidic chip seals, culture dish gaskets

4. Platinum vs. Peroxide: Real Differences in Medical Applications

One case illustrates the difference clearly: a medical device supplier received two orders for medical silicone tubing—one specifying platinum curing, the other choosing the cheaper peroxide-cured option.

After three months, the peroxide-cured product began receiving complaints about yellowing, hardening, and a “plastic” odor. The cause was that peroxide decomposition residues gradually migrated out during repeated high-temperature sterilization, leading to material degradation. The platinum-cured product remained stable under the same conditions.

More importantly, peroxide-cured products frequently struggle with cytotoxicity and sensitization tests in biocompatibility evaluations, requiring repeated re-testing and causing delays.

5. Baby Products: A Must-Have Application for Platinum Curing

Baby silicone products are among the most typical applications for platinum curing. Silicone nipples, teethers, feeding bowls, and sippy cups must meet both food-grade safety and long-term durability requirements.

Characteristics of platinum-cured baby silicone products include:

No odor after boiling for 120 minutes, supporting repeated high-temperature disinfection.

No whitening during long-term use, due to a more uniform crosslink network and slower aging.

Low migration, halogen-free, and no heavy-metal leaching, meeting child-product safety regulations worldwide.

High transparency, allowing caregivers to visually check cleanliness.

6. Cost Considerations: Why Platinum Curing Is “More Expensive”

Platinum-cured products are typically 30% to 100% more expensive than peroxide-cured ones. But this price difference is not just material cost—it reflects compliance and safety costs:

Platinum catalysts are more expensive than peroxides.

Platinum curing requires higher-purity raw materials (low-impurity fillers, high-purity silicone oils).

Production environments must meet higher cleanliness standards.

Certification testing costs are significant, especially for full ISO 10993 testing.51319

For products targeting food, medical, and infant markets, this “compliance cost” is unavoidable. Peroxide curing may have lower raw-material costs, but if biocompatibility tests fail, the time and expense of re-validation can be even higher.

Summary

Platinum catalysts have become the standard for food-grade and medical-grade silicone because the addition-cure reaction they catalyze produces no by-products, resulting in exceptionally high product purity. This enables compliance with the strictest FDA food-contact standards and ISO 10993 biocompatibility requirements.11123 In these markets, safety is not a bonus—it is the entry threshold. Platinum curing is not merely a “better” choice; in many cases, it is the only viable choice.


Diethylenetetramethyldisiloxane platinum complex (platinum catalyst) MY 8113-Mingyi Silicone