ADC / OBSH / Sulfonyl Hydrazide Blowing Powder | Chemical Blowing Agent for Peroxide-Cured Silicone

Short Description

Many manufacturers of solid milled silicone with 2,5-Dimethyl-2,5-di(tert-butylperoxy)hexane (DBPH / two-five) curing struggle with incompatible foaming additives. Expandable microspheres tend to rupture prematurely under high-temperature milling and compression molding. Sodium bicarbonate compound foaming powder cannot withstand high curing temperature and leads to foam collapse. Many blowing agents interfere with peroxide curing, causing incomplete crosslinking, blisters and cell collapse. ADC, OBSH and sulfonyl hydrazide series blowing powders are high-temperature chemical blowing agents customized for peroxide-cured milled silicone. They release nitrogen upon thermal decomposition. Their decomposition window matches the curing cycle of peroxide silicone. Widely used for solid silicone foam sheets, thick foam gaskets and silicone sponge. Supplied in powder form, available for direct use or compounding. Samples and bulk supply are supported.

✅ Solve Your Common Production Pain Points

❌ Pain 1: Expandable microspheres break and pre-expand during high-temperature milling & molding 

✅ Benefit: Matched to high-temperature DBPH curing process, foaming and curing happen synchronously, less premature cell rupture 

❌ Pain 2: Low-temperature citrate-bicarbonate foaming powder cannot survive peroxide curing heat, foam collapses easily 

✅ Benefit: High-temperature grade formula, gas release window aligns with silicone curing temperature 

❌ Pain 3: Incompatible additives hinder peroxide crosslinking, resulting in under-cure, blisters and collapsed cells 

✅ Benefit: Formulated for peroxide vulcanization system, no curing inhibition, stable foaming & crosslinking 

❌ Pain 4: Limited temperature grades make it hard to match thick molded parts, thin calendered sheets or extrusion lines 

✅ Benefit: Multiple grades for selection: ADC with high gas yield, OBSH for fine cells & low heat release, sulfonyl hydrazide with wide temperature range 

❌ Pain 5: Looking for cost-efficient raw material while keeping uniform cells and good resilience 

✅ Benefit: Lower raw material cost vs expandable microspheres; proper grade delivers fine closed cells and stable sealing performance 

❌ Pain 6: Heavy odor and harmful residues from decomposition cause trouble for post-processing and export compliance 

✅ Benefit: OBSH grade is low formamide, low odor; ADC delivers high gas output, select by your environmental requirement

Key Features

• Designed for peroxide (DBPH / two-five) cured milled silicone. NOT FOR platinum addition-cure silicone, will cause platinum poisoning
• Multiple series: ADC (high gas yield), OBSH (fine cells, low exotherm, eco-friendly), sulfonyl hydrazide grades with variable decomposition temperature
• Releases nitrogen gas on heating, controllable expansion ratio, suitable for thick molding, extrusion, continuous calendering of solid silicone
• Good dispersion, easy mixing with milled silicone rubber
• Can be dosed directly or compounded into foam master paste / masterbatch
• Packed in bags or drums, samples & bulk orders available

Main Applications

• Peroxide-cured milled silicone foam sponge, thick foam sealing gaskets
• Calendered silicone foam sheets, extruded foam silicone profiles
• Automotive shock-absorbing foam silicone parts, heat-resistant cushion foam
• Raw material for compounding high-temperature foam masterbatch
• Foaming for EPDM and other peroxide-crosslinked elastomers

Technical Guide

• Appearance: Powder (ADC: pale yellow; OBSH / sulfonyl hydrazide: off-white / white powder)
• Decomposition temperature: ADC:190–220℃; OBSH:140–160℃; Sulfonyl hydrazide:130–180℃
• Recommended dosage: 1–3 wt%, adjust based on target density, expansion ratio and part thickness
• Packing: 20kg/bag or 25kg/drum
• Note: Forbidden in platinum addition silicone systems, it poisons platinum catalyst and stops curing. High-temperature vulcanization required. Lab trial is strongly recommended before mass production.