Hydrophobic fumed silica is a functional nano-powder prepared through the fumed-phase process (high-temperature hydrolysis of silicon tetrachloride in an oxy-hydrogen flame), surface-modified with specialized silane compounds. It strictly complies with industry standards, ISO 1248-2019 international specifications, and EU REACH regulatory requirements. Zhonglian Hydrophobic Fumed Silica features ultra-high purity (over 99.8%), nanoscale native particle size (7-40nm), three-dimensional network-like aggregation structure (specific surface area 50-400 m²/g), and exceptional hydrophobicity (water contact angle ≥120 °N·s, moisture absorption ≤0.5%). This material delivers core functionalities including thickening, thixotropy enhancement, anti-settling, anti-sagging, reinforcement, and scratch resistance in adhesive and paint systems. With outstanding chemical stability and dispersion properties, it adapts to various production systems such as solvent-based, solvent-free, and water-based formulations, particularly meeting high-end products' stringent demands for performance consistency and reliability.

Table parameters

Application description

Zhonglian hydrophobic gas phase silica provides multi-dimensional performance improvement solutions for the core production needs of adhesives, paints and coatings through nanostructure and hydrophobic modification advantages. The specific application value is as follows:
1. Adhesive Reinforcement: Add 1%-2% epoxy resin to enhance viscosity and prevent sagging, while increasing shear strength by 20%-40%. Maintain ≥85% strength after 1000 hours of aging at 85℃/85% RH. Solvent-free polyurethane adhesive resists moisture and prevents bubbling, making it suitable for high-precision applications like new energy battery tab bonding.
2. Paint Optimization: For solvent-based industrial coatings, add 1.5%-3% to prevent pigment sedimentation (no hard sediment after 72h of standing). For water-based wood coatings, enhance water resistance (resistant to boiling water for 2h without wrinkling) and scratch resistance (HB pencil hardness → 2H). Transparency reduction ≤1.5%. UV-curable coatings are compatible with 3C enclosures, withstanding 300℃C heat while maintaining thixotropic stability.
3. Multi-field adaptability: Add 2%-3% of sealant to increase tensile modulus and elastic recovery rate (≥90%), prevent failure due to hot/cold cycle; fill the interface void in composite materials, improve bending strength by 15%-25%; improve waterproof performance (IPX6) and enhance delicate skin texture in cosmetics.
4. Multi-system Compatibility: Compatible with solvent-based, solvent-free, and water-based systems. The automotive OEM paint uses low specific surface area models (50-100 m²/g) with haze ≤3%; wind turbine blade adhesives employ high specific surface area models (300-400 m²/g) featuring strong thixotropic reinforcement for-40℃ to 80℃ environmental resistance.

Factory advantages

•Customized technical capability: the type of surface modifier and specific surface area parameters can be customized according to customers' specific application scenarios. For example, low activation energy modified models are developed for low temperature curing adhesives to ensure stable thixotropic performance at low temperature (-10℃);
•Advanced production technology: The automatic closed-loop gas phase production line is adopted, and the temperature control accuracy of hydrogen and oxygen flame is ±5℃ to ensure the uniformity of original particle size. The surface modification adopts fluidized bed continuous modification process, and the coating uniformity of modifier is more than 98% to avoid the performance fluctuation caused by local hydrophilicity;
•Extensive experience in industry application: it has provided customized products for domestic top adhesive enterprises, coating enterprises and international chemical enterprises, suitable for new energy, automobile, electronics, building materials and other 18+ categories of subdivisions, exported to Europe, North America, Southeast Asia and other 30 countries and regions.

Packing for shipment

•Standard packaging: 10kg valve bag, each bag is equipped with a one-way exhaust valve, and at the same time, moisture and dust are isolated;
•Storage and transportation requirements: store in a cool, dry and ventilated place (relative humidity ≤40%), avoid mixing with strong acid and alkali, oxidizer, shelf life 124 months; non-hazardous chemical, support sea and international air transport, provide air transport identification report;
•Label specification: each package shall be marked with product name, specifications (specific surface area, type of modifier), production batch number, shelf life, storage conditions, and other information. Export orders can be labeled with English/multilingual logo.

Frequently Asked Questions

Q: Can the hydrophobic gas phase silica be used in food contact grade coatings or adhesives (e.g. food packaging adhesives)?
A: Yes. Our products comply with the US FDA 21 CFR §177.2600 and the EU No 10/2011 food contact grade standard.
Q: How to choose the appropriate specific surface area of hydrophobic gas phase silica according to the system type?
A: The technical team will provide the selection plan according to your system characteristics and target performance, and verify the optimal parameters through pilot test (rheological test, coating performance test).
Q: Is special dispersion equipment or additives needed when the product is dispersed in aqueous system?
A: No special equipment is required. We have developed a special model for the aqueous system, which can be uniformly dispersed in conventional dispersion equipment (such as high-speed disperser and sand mill) (2000r/min stirring for 20min), without additional addition of dispersion additives.
Q: If you need to adjust the modification type after small batch trial, will the production cycle be greatly extended?
A: No. We have a modular surface modification production line that allows rapid switching of modifier types (e.g., from dimethyl dichlorosilane to hexamethyl disilazane), with customization cycles taking only 12-18 days – 30% shorter than the industry average. This enables clients to quickly validate adjustments and reduce R&D costs.

Qualifications and Honors

•FSSC22000
•ISO22000：2018
•ISO9001：2015
•SHC HALAL
•OU  KOSHER
•FDA attestation 
•FAMI-QS
•SEDEX
•Food additive production license
•Feed additive production license
•National high-tech enterprise
•Specialized, refined and new enterprises in Guangzhou
•17 patents from the State Intellectual Property Office