Acetic silicone sealants cure quickly and have strong adhesion, but release acetic acid gas and are corrosive to metals and alkaline substrates. Neutral silicone sealants cure relatively slowly, have balanced adhesion performance, are non-corrosive, offer superior weather resistance, and have broader applications.
I. Chemical Curing Mechanism
Acetic Silicone Sealants
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Single-component, based on polydimethylsiloxane (PDMS)
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React with moisture in air, releasing acetic acid (CH₃COOH) during curing
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Commonly known as deacetylation-type silicone sealants
Neutral Silicone Sealants
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Single-component, based on PDMS
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React with moisture in air, releasing alcohols (such as ethanol, methanol) during curing
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Commonly known as dealcoholization-type (or deketoxime-type) silicone sealants
II. Performance Comparison
Curing Products: Acetic sealants release acetic acid with a pungent odor and Grade I-II irritation, while neutral sealants release alcohols with mild odor and no irritation.
Curing Speed: Acetic sealants cure rapidly with surface drying time of 0.5-3 hours and 24-hour curing thickness of 5-6mm. Neutral sealants cure more slowly with surface drying time typically 6-12 hours and 24-hour curing thickness of 2-4mm.
Adhesion Strength: Acetic sealants have stronger adhesion with tensile strength of 1.0-3.2 MPa, while neutral sealants have good adhesion but slightly inferior to acetic types.
Weather Resistance: Acetic sealants offer good performance from -40°C to +150°C with UV resistance, while neutral sealants provide superior performance from -40°C to +200°C with excellent anti-aging and anti-ozone properties.
Corrosiveness: Acetic sealants corrode copper, aluminum, steel and other metals as well as alkaline materials, while neutral sealants are non-corrosive and can directly contact metals, concrete, and marble.
Construction Applications: Acetic sealants are suitable for general bonding and sealing between glass and non-alkaline plastics or wood, while neutral sealants are ideal for weatherproofing curtain walls, doors, windows, stone materials and various building materials.
Price Level: Acetic sealants are relatively lower-priced, while neutral sealants are more expensive.
III. Application Scenarios
Acetic Silicone Sealants
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Indoor glass, aluminum alloy doors and windows, display windows for non-structural bonding and sealing
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Sanitary fixtures, mirror backing and other applications not requiring high weather resistance
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Projects requiring rapid curing and short construction periods
Neutral Silicone Sealants
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Building curtain wall (glass, aluminum composite panels, stone dry-hanging) weatherproof sealing
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Various substrates including metals, concrete, marble, wood and other material joints
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Long-term outdoor exposure environments (UV resistance, weathering resistance, high and low temperature tolerance)
IV. Selection Recommendations
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Metals and Alkaline Materials: Must use neutral silicone sealants to avoid corrosion or bubbling.
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Outdoor Weather Resistance: Neutral sealants have superior anti-aging performance, recommended for curtain walls and exterior wall joints.
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Structural Bonding: Neither type is suitable for load-bearing structural bonding; both are for sealing purposes only.
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Construction Timeline: When rapid curing is needed and substrate has no corrosion concerns, acetic sealants may be selected.
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Environmental and Odor Considerations: For odor-sensitive environments or poorly ventilated areas, low-odor neutral sealants are preferred.
References
Acetic Silicone Sealant_Baidu Encyclopedia
Simple Introduction to Neutral Silicone Weather Sealants – Liansu Building Materials Home Station
How to Distinguish Acetic and Neutral Glass Sealants – Guangzhou Xinxin Trading Co., Ltd.
Acetic Silicone Glass Sealant_Baidu Encyclopedia
Common Questions and Answers about Neutral Silicone Weather Sealants – Adhesive Sealant
