Complete classification of defoamer+selection guide (paint/lotion, water-based system, suitable for latex paint, water-based industrial paint, adhesive, lotion synthesis)
1、Main categories, structures, advantages and disadvantages, and applicable systems of mainstream defoamers
1. Mineral oil defoamer
Main components: mineral base oil+hydrophobic silica dioxide+emulsifying dispersant
✅ Advantages
Balanced foam suppression and bursting, with the highest cost-effectiveness; Long term foam suppression; Moderate compatibility
❌ shortcoming
Excessive addition can lead to shrinkage and loss of gloss; Not resistant to high temperatures; Cannot be used for transparent topcoats; Easy to affect the gloss of paint film Applicable: water-based primer, thick paste paint, internal and external wall emulsion paint, cement mortar, water-based filler slurry, defoaming before production of lotion Not recommended: high gloss varnish, transparent paint, film coating
2. Polyether defoamer (polyoxyethylene polyoxypropylene ether)
Subdivision: ordinary polyether, branched polyether, block polyether
✅ Advantages
Excellent compatibility, not prone to shrinkage; Transparent system friendly; Low surface tension; High temperature resistance; Suitable for fermentation, cleaning and fine lotion system
❌ shortcoming
Weak bubble breaking ability and slow elimination of large bubbles; Foam suppression is greatly reduced at low temperature Applicable: water-based varnish, transparent lotion, textile size, water-based cutting fluid, acrylic lotion polymerization, high transparent system Not recommended: high solid content, a large number of micro foam stabilizing agent systems (only polyether is difficult to eliminate micro bubbles)
3. Organosilicon defoamers (with the largest industry usage, further divided into 3 subcategories)
(1) Pure polydimethylsiloxane (silicone oil stock solution)
Extremely strong bubble breaking, poor compatibility, prone to shrinkage and fisheye, rarely used directly alone
(2) Lotion type silicone defoamer (modified silicone oil+emulsifier, water-based general type)
✅ Advantages: Top breaking ability, capable of killing both large and small bubbles; Low addition amount; Good stability at high and low temperatures ❌ Disadvantages: Improper selection can easily lead to shrinkage; Risk of re coating adhesion; The color pigments in the system are acceptable, and the transparent system should be carefully applied: industrial water-based paint, lotion, water-based ink, papermaking paint
(3) Polyether modified organosilicon (silicone polyether, high-end universal version)
Polyether grafted silicone oil, balancing the strong foam breaking properties of silicon and excellent compatibility with polyether
✅ Advantages: Excellent microbubble elimination, significantly reducing the risk of shrinkage; Can be used for transparent paint and high gloss systems; Combining foam breaking and foam suppression
❌ Disadvantages: higher price Applicable: high gloss water-based varnish, polyurethane lotion, water-based wood paint, high-end acrylic lotion
4. Non silicone polymer defoamers (acrylic, polyolefin)
Ingredients: Hydrophobic acrylic polymer, aliphatic polymer, no silicon, no mineral oil
✅ Advantages: completely free of silicon, without silicon pollution or re coating obstacles; The gloss of the paint film has little impact; Very few shrinkage cavities; Suitable for processes without silicon residue
❌ The disadvantage is that the foam suppression persistence is average; The effect of dense microbubbles is weaker than that of organosilicon; High unit price applicable scenarios focus on: requiring secondary spraying and multi-layer recoating system; There should be no silicon pollution (printing, coating, food contact coating, automotive paint); High gloss topcoat and varnish
5. Special category defoamers
Organic fluorine defoamer: extremely low surface tension, super strong defoamer; Expensive price; Mostly used in special systems (high surface active surfactant systems), rarely used in ordinary coatings
Powder defoamer: mineral oil/silicon loaded on the carrier; Dry powder mortar, powder coating, powder building materials
2、Comparison Table of Core Performance of Various Defoamers
Type: Bubble breaking ability, Bubble suppression duration, Compatibility, Shrinkage risk, Repainting cost, Suitable for microbubbles
Mineral oil medium long medium high good low average
Ordinary polyether weak, medium, excellent, low, excellent, medium, poor
Organosilicon lotion is extremely strong, medium high, medium excellent
Silicon Polyether (Polyether Modified Silicon) Strong, Long, Good, Low, Good, High, Excellent
Silicon free polymer, short, excellent, very low, excellent, high, medium
3、Selection Core Judgment Criteria (Practical Guide)
Step 1: Determine the system attributes first
1) Water based system (acrylic lotion, PU lotion, emulsion paint)
Primer and engineering latex paint: priority mineral oil defoamer (cost priority)
Matte finish, ordinary industrial paint: silicone lotion defoamer
High gloss varnish, transparent lotion: silicone polyether modified defoamer/silicone free polymer defoamer
Multiple layers of recoating are required to prevent silicon contamination: ordinary silicone oil is prohibited, and silicon free polymers are selected
2) High solid lotion, containing a large amount of emulsifier (easy to produce microbubbles)
Micro bubble (micro airtight bubble): polyether effect is poor, preferred silicone polyether/silicone lotion
3) Solvent based system: Oil soluble organosilicon, polyether (water-based defoamers cannot be directly added to the solvent system)
Step 2: Distinguish between “large bubbles” and “microbubbles”
Large bubbles float on the liquid surface → Mineral oil and polyether can both be treated
After the paint film dries, pinholes and fine bubbles (internal microbubbles) appear, which must contain silicone defoamers
Step 3: Processing Technology Conditions
Lotion polymerization (high temperature stirring foaming in reactor): high temperature resistant polyether or temperature resistant silicon polyether
Sand grinding high-speed dispersion (strong shear): choose defoamers with strong emulsifying stability, which are not easy to separate and break emulsions under high shear
Low temperature construction environment: Ordinary polyether fails at low temperatures, replace with silicon-based defoamers
Step 4: Forbidden Red Line
The system requires electroplating, bonding, and printing in the future → use all unmodified organic silicon with caution, as silicon migration can cause adhesion failure
High gloss transparent coating: Do not use mineral oil alone, it is easy to lose gloss
Mixing of anionic/cationic systems: Pay attention to the ionicity of defoamers and avoid flocculation and emulsion breaking (the vast majority of industrial defoamers are non-ionic)
4、Recommended addition amount (water-based paint/lotion reference)
Mineral oil defoamer: 0.3% to 1.0% (total amount)
Organic silicon lotion defoamer: 0.1% ～ 0.5%
Silicone polyether defoamer: 0.15% to 0.6%
Silicone free polymer defoamer: 0.2% to 0.8%
✔ Practical principle: Minimum effective addition amount, excessive amount will definitely cause shrinkage, decreased gloss, and side effects
5、Simple and Quick Selection Formula
Engineering latex paint, primer, cost control → mineral oil defoamer
Ordinary water-based industrial paint, with many pinholes and micro bubbles, does not consider recoating → silicone lotion defoamer
High gloss varnish, transparent lotion, want to reduce shrinkage cavity → silicone polyether modified silicone
Multi layer recoating, no silicon contamination, high-end topcoat system → silicon free polymer defoamer
Foam control and transparent low foam system in lotion polymerizer → block polyether defoamer
Post time: Aug-06-2026