Peroxide-cured EPDM Deodorizer

Product Introduction

In the high-end rubber industry, peroxide cross-linking systems (e.g., DCP, BIPB) grant EPDM excellent heat resistance and extremely low compression set. However, during high-temperature cleavage and cross-linking, they release highly pungent oxygenated volatile organic compounds (VOCs), primarily acetophenone, cumyl alcohol, and other aldehydes, ketones, and alcohols. Traditional metal zinc salt deodorizers lack the chemical capture capability for these oxygenated odor molecules and can cause system instability due to polarity conflicts.

This product is a reactive, odorless deodorizer specially developed for peroxide-cured EPDM systems. It completely reconstructs the odor elimination logic using a solid composite system design with multi-component synergy. The formula introduces a chemical association agent with highly active aldehyde and ketone reactive groups, precisely targeting and neutralizing odor molecules like acetophenone generated by peroxide cleavage. Simultaneously, through unique in-situ melt anchoring technology under high temperature and high shear in the internal mixer, the active deodorizing molecules are uniformly dragged and locked into the high-viscosity rubber cross-linking network, achieving long-term stable dispersion and excellent compatibility. The product is neutral, completely free of heavy metals like zinc and harmful benzenes, perfectly protecting the safety of peroxide cross-linking free radicals. It drastically reduces VOC emissions of final products, easily meeting strict indoor air quality and environmental testing standards.

Appearance

White powder.

Deodorizing Principle

• Multifunctional Chemical Association: Deodorizer molecules are designed with highly active aldehyde and ketone reactive groups. Under vulcanization temperatures, they accurately identify and attack the carbonyl groups of odor molecules like acetophenone, undergoing an irreversible dehydration condensation reaction. This transforms them into stable, non-volatile complexes with large molecular weights, eliminating the odor source.
• Targeted Locking of Oxygenated Volatiles: Built-in abundant micro-nano porous structures act as microscopic physical sponges, specifically and efficiently capturing and locking oxygenated small molecules like alcohols and free alkanes generated during cleavage.
• Physical Anchoring & Excellent Compatibility: The specialized carrier has an amphiphilic structure. The polar end adsorbs the main deodorizing agent, while the non-polar long chain is deeply miscible with EPDM raw rubber and processing oil. After high-temperature crosslinking, the active components are firmly "anchored" in the rubber 3D network, achieving perfect compatibility and long-lasting odor purification.

Application Areas

• Automotive Rubber & Plastic Parts: Odor removal for high-end automotive EPDM cooling water pipes, heater hoses, and low-VOC (e.g., VDA 270 standard) cabin interior EPDM seals and foamed acoustic shock-absorbing pads.
• Fluid Sealing & Food-Grade Rubber: Direct drinking water system EPDM O-rings, potable water fittings, food, and medical-grade rubber miscellaneous parts (heavy-metal-free, RoHS and REACH compliant).
• Home Materials & Industrial Products: Eco-friendly indoor solid and foamed EPDM sealing strips for doors and windows, low-odor industrial rubber hoses, and cable insulation sheathing systems.

Usage Method

• Adding Method: In the internal mixer, it is recommended to add this product simultaneously with raw rubber and partial fillers (carbon black, silica) during the initial mixing stage to ensure full dispersion and effective contact with odor molecules.
• Mixing Requirements: Ensuring the powder is uniformly dispersed in the rubber compound is crucial. It is highly recommended to use a high-speed mixer to pre-disperse this product with dry powder fillers before feeding into the internal mixer, ensuring maximized reaction site contact. Mix thoroughly during the first-stage internal mixing, then add processing oil as per normal procedure.
• Curing System Addition: Peroxide curing agents and co-crosslinkers (like TAIC) must be added last during the second stage of mixing (open mill or low-temp internal mixing) to prevent premature scorching.

Reference Dosage

• Recommended Dosage: Add 0.3% - 1.0% based on the total material weight.
• Starting Test Dosage: To achieve optimal results, it is recommended to start testing at the lower limit (0.5% for foamed products, 0.3% for solid non-foamed parts), adjusting to find the best dosage based on final deodorization and VOC reduction performance.

Precautions

• The in-situ anchoring mechanism of this product depends on high temperatures to trigger. It is strongly recommended that the first-stage internal mixing temperature reaches above 145°C to fully melt the carrier and fuse it deeply with the rubber matrix. Do not add the powder separately during the low-temperature second-stage curing phase.
• For continuously extruded solid non-foamed parts, as the chemical association reaction may release trace amounts of moisture, it is recommended to slightly increase the negative pressure in the vacuum exhaust section during extrusion to prevent residual moisture inside the rubber.