Product name: Hydroxy vinyl silicone fluid

Alias: Silanol Terminated methyl vinyl silicone fluid

Product code: NV-SIOH204

Chemical Informations:

Main Composition:Siloxanes and Silicones, di-Me, Me vinyl, hydroxy-terminated (Hydroxy-terminated polydimethylvinylsiloxane)

Molecular Structure:HO-[Si(CH3)2-O]-[Si(CH3)(CH=CH2)-O]-H

Cas No.:67923-19-7

Chemical Character: NV-SIOH204 is a low-viscosity, reactive silicone fluid featuring both terminal hydroxyl groups (silanol) and vinyl functional groups along the polydimethylsiloxane (PDMS) backbone. .

Product Description:

NV-SIOH204 is a low-molecular-weight structural control agent and chemical intermediate featuring a unique dual-functional architecture. The presence of high-density silanol (Si-OH) functionality ensures rapid condensation or anchoring reactions with inorganic filler surfaces (such as fumed silica), effectively preventing the structured hardening ("creping") of silicone compounds. Meanwhile, the precisely controlled vinyl groups (Si-CH=CH2) are perfectly positioned to participate in subsequent addition-cure (hydrosilylation) or peroxide-cure networks. This versatile crosslinking mechanism not only significantly increases crosslinking density and adjusts the final mechanical modulus but also makes NV-203V an exceptional high-efficiency modifier for advanced silicone rubbers, coatings, and structural sealants.

Typical properties:

Appearance:Colorless transparent liquid

Viscosity (25℃, mm²/s): 35

Hydroxyl Content (wt%)≥5.0%

Vinyl Content (mol%):6.5-7.5%

Water Content (wt%)≤0.5%

Key Benefits & Features

Dual-Reactive Sites: Combines condensation-curable silanol groups with addition-curable vinyl groups for multi-stage or customized polymer networks.

Outstanding Anti-Creping Performance: High hydroxyl content (≥5.0%) provides exceptional surface modification on silica clusters, reducing processing times for premium HTV/LSR compounds.

Low Viscosity Control: Viscosity below 35 mm2/s ensures rapid wet-out, lower processing torque, and easy incorporation without high-shear compounding limitations.

Mechanical & Thermal Enhancement: Introduces rigid, dense crosslinking nodes through its high vinyl concentration (6.5–7.5 mol%), elevating tear strength, hardness, and thermal resistance of the cured matrix.

Recommended Applications

1. Structure Control Agent for HTV Silicone Rubber (Core Application)

This product is highly recommended as a dual-function additive in High Consistency Rubber (HTV) compounding:

Processing Aid: The hydroxyl (-OH) groups react with silica surfaces to prevent filler agglomeration and "crepe hardening" (structure-up) during storage, significantly improving processability.

Performance Enhancer: The vinyl groups participate in the crosslinking reaction (peroxide cure system), forming a denser network that enhances mechanical properties such as tear strength and resilience.

2. Reactive Plasticizer & Modifier for LSR and Sealants

For Liquid Silicone Rubber (LSR): Its low viscosity ensures rapid mold filling, while the dual functionality improves filler compatibility and ensures deep-section curing.

For Electronic Sealants: Acts as a non-migrating reactive plasticizer in addition-cure systems. It reduces viscosity and adjusts tack/modulus without compromising the integrity of the cured network.

3. Release Force Regulator

Used in addition-cure release coatings (e.g., for paper and films) to precisely modulate release force. The hydroxyl groups improve adhesion to the substrate, while the vinyl groups ensure compatibility with the coating system.

4. Surface Treatment & Resin Modification

Filler Treatment: Optimizes the dispersion and bonding of glass fibers, mineral fillers, and pigments in polymer composites.

Resin Modification: Serves as a reactive intermediate for synthesizing silicone-modified resins (acrylics, polyurethanes, polyesters), imparting weatherability, low-temperature flexibility, and hydrophobicity.

Handling & Precautions

Incorporation: Add during the kneading/mixing stage along with the silica filler and base polymer. High-shear milling equipment is not mandatory for standard reactive mixing.

Preparation: Ensure proper mechanical agitation before blending, especially if the compound has been stored under low temperatures.

Recommended Dosage: 2–8 phr (parts per hundred rubber) in HTV compounding, depending on filler type and loading.

Compatibility: Can be used alone or in combination with conventional hydroxy silicone oil.

Precautions: Due to the presence of reactive silanol and vinyl groups, contact with strong acids, bases, strong oxidizers, or trace moisture should be strictly avoided to prevent premature condensation or gelation.

Packaging

25 kg Plastic pails;200 kg Iron or plastic drum; 1000 kg IBC Totes