THE BEST Hydrophobic Fumed Silica MANUFACTURER in China

Hubei Huifu Nanomaterial Co., Ltd. is a chemical manufacturer of nanomaterials in China, Our main products are fumed silica, fumed titanium dioxide, and fumed alumina Al2O3. We get 20+ years of expertise and 12,000 tons annual capacity.

HIFULL Hydrophobic Fumed Silica

Hydrophobic fumed silica is a form of silicon dioxide (commonly known as silica) that has hydrophobic groups chemically bonded to the surface. It’s treated silica or structure-modified silica. HIFULL hydrophobic fumed silica is structure modified silica after being treated by HMDS, PDMS, DDS.

Hydrophobic FUMED SILICA

 Hydrophobic fumed silica is structure-modified silica after being treated by HMDS, PDMS, DDS and other special silanes.

HMDS treatment

Hexamethyldisilazane (HMDS) is a chemical compound that is commonly used as a surface treatment for fumed silica to make it hydrophobic. The hydrophobic treatment involving HMDS enhances the dispersibility and compatibility of fumed silica in hydrophobic systems. The HMDS molecules attach to the surface of the silica particles, creating a water-repellent coating. This modification improves the performance of fumed silica in various applications.

Hydrophobic fumed silica, treated with HMDS, is widely used in industries such as paints and coatings, adhesives and sealants, cosmetics, plastics, rubber, and composites. It is added to formulations to improve properties like rheology, thixotropic behavior, stability, moisture resistance, and flow control.

HIFULL® HB-132 (BET=140㎡/g)

HIFULL® HB-132 (BET=140㎡/g) HB-132 hydrophilic Fumed Silica HB-132 is Hydrophobic Fumed Silica produced by hydrophilic fumed silica with a specific surface area of 200m2/g after chemical post-treatment with HMDS (Hexamethyldisilazane)…

HIFULL®HB-612 (BET=150㎡/g)

HIFULL® HB-612 (BET=150㎡/g) HB-612 hydrophilic Fumed Silica HB-612 is Hydrophobic Fumed Silica produced by hydrophilic fumed silica with a specific surface area of 150m2/g after chemical post-treatment with HMDS (Hexamethyldisilazane)…

HIFULL® HB-615 (BET=140㎡/g)

HIFULL® HB-615 (BET=140㎡/g) HB-615 hydrophilic Fumed Silica HB-615 is Hydrophobic Fumed Silica produced by hydrophilic fumed silica with a specific surface area of 180m2/g after chemical post-treatment with HMDS (Hexamethyldisilazane)…

HIFULL® HB-620 (BET=200㎡/g)

HIFULL® HB-620 (BET=200㎡/g) HB-620 hydrophilic Fumed Silica HB-620 is Hydrophobic Fumed Silica produced by hydrophilic fumed silica with a specific surface area of 200m2/g after chemical post-treatment with HMDS (Hexamethyldisilazane)…

HIFULL® HB-630 (BET=400㎡/g)

HIFULL® HB-630 (BET=400㎡/g) HB-630 hydrophilic Fumed Silica HB-630 is Hydrophobic Fumed Silica produced by hydrophilic fumed silica with a specific surface area of 400m2/g after chemical post-treatment with HMDS (Hexamethyldisilazane)…

PDMS treatment

PDMS (Polydimethylsiloxane) hydrophobic fumed silica refers to fumed silica particles that have been surface-treated with PDMS to make them hydrophobic. When PDMS is applied to the surface of fumed silica particles, it forms a hydrophobic coating. This modification enhances the dispersibility and compatibility of fumed silica in hydrophobic systems. The PDMS molecules attach to the silica surface, creating a water-repellent layer.

HIFULL® HB-139 (BET=180㎡/g)

HIFULL® HB-139 is hydrophobic fumed silica which is produced by hydrophilic fumed silica with a specific surface area of 200m2/g after chemical post-treatment with PDMS / Polydimethylsiloxane, also known as silicone oil. Compared to untreated hydrophilic fumed silica,…

DDS treatment

HIFULL® HB-151(BET=150㎡/g)

HIFULL® HB-151 (BET=150㎡/g) HB-151 hydrophilic Fumed Silica HIFULL® HB-151 is Hydrophobic Fumed Silica which is produced by hydrophilic fumed silica with a specific surface area of 150m2/g after chemical post-treatment with DDS(Dimethyldichlorosilane)…

HIFULL®HB-152 (BET=170㎡/g)

HIFULL® HB-152 (BET=170㎡/g) HB-152 hydrophilic Fumed Silica HB-152 is Hydrophobic Fumed Silica which is produced by hydrophilic fumed silica with a specific surface area of 170m2/g after chemical post-treatment with DDS(Dimethyldichlorosilane)…

special silane

HIFULL®HB-701 (BET=150㎡/g)

HIFULL® HB-701 (BET=150㎡/g) HB-701 hydrophilic Fumed Silica HB-701 is surface-treated fumed silica with active silanol group modified by special silane. Properties

HIFULL® HB-202N (BET=170㎡/g)

HIFULL® HB-202N (BET=170㎡/g) HB-202N hydrophilic Fumed Silica HB-202N is hydrophobic fumed silica that has been treated by special manufacturing process to increase the polarity of the product. Properties


*Registrations: HIFULL fumed silica products get registrations of REACH & Pre-registration of K-REACH &KKDIK  

GradeTreating AgentSpecific Surface Area (nitrogen adsorption method) (m²/g)pH value in dispersionLoss on drying(2 hour at 105℃)Loss on ignition (%)Silica content (%)Carbon content(%)Tamped density (g/L)Product application
HB-612HMDS140±205.0~8.0≤0.7≤2.0≥99.80.7~1.340~60Roomtemperaturevulcanization (RTV)silicone rubber, ceramics, pesticides, defoamers
HB-615HMDS140±205.0~8.0≤0.7≤4.0≥99.81.0~1.740~60Ink, electronic potting adhesive, defoamer, silicone rubber
HB-620HMDS170±306.0~9.0≤0.7≤4.0≥99.81.5~2.540~60Silicone rubber, powder coating, defoamer, paint
HB-630HMDS300±306.0~9.0≤0.7≤5.0≥99.82.5~4.040~60Silicone rubber, powder coating, defoamer, paint
HB-132HMDS140±206.0~9.0≤0.7≤4.0≥99.82.0~4.040~60Silicone rubber, defoamer, adhesive, sealant
HB-139PDMS110±304.0~7.0≤0.7≤10.0≥99.84.0~7.040~60Powder coatings, adhesives, coatings, sealants
HB-151DDS120±30≥3.7≤0.7≤2.5≥99.80.6~1.240~60Coatings, inks, adhesives, MS adhesives
HB-152DDS170±30≥3.7≤0.7≤2.5≥99.80.8~1.640~60Coatings, inks, adhesives, MS adhesives
HB-202NSpecial Silane Treated170±208.0~10.0≤2.0≤8.0≥99.81.0~2.040~60Coatings, anticorrosive coating products, grinding of copper products, water-based inks and water-based coatings
HB-701Special Silane Treated150±254.0~6.0≤1.5≥4.5≥99.84.5~6.540~60Paint and coating systems, plastics and elastomers, dental composites

Performance benefit

For systems requiring hydrophobic grades, HIFULL treated fumed silica deliver a number of performance benefits including:

  • Reduced moisture adsorption
  • Anti-settling, thickening and sag resistance in polar systems
  • Optimum rheology during processing
  • Reinforcement of silicone elastomers
  • High levels of loading, e.g. molding compounds
  • Excellent water-repelling properties leading to improved corrosion protection
  • Improvement of dielectric properties, cable compounds
  • Free-flow of powders, e.g. in fire extinguishers
  • Increased scratch resistance, e.g. of paints and plastics

Fumed silica, or pyrogenic silicon dioxide, is one kind of pure amorphous white inorganic powder that has a high specific surface area, nano-scale primary particle size, and a relatively high (among silica products) concentration of surface silanol groups. The properties of fumed silica can be chemically modified by reaction with these silanol groups.

Commercial available fumed silica can be divided into two groups: hydrophilic fumed silica and hydrophobic fumed silica. Because of the above-mentioned features, it is widely used as an important ingredient in many industries such as silicone rubber, paint, and plastics industries.


HB-612Hydrophobic Fumed SilicaHMDS-TreatedDownloadDownload
HB-615Hydrophobic Fumed Silica HMDS-TreatedDownloadDownload
HB-620Hydrophobic Fumed Silica HMDS-TreatedDownloadDownload
HB-630Hydrophobic Fumed SilicaHMDS-TreatedDownloadDownload
HB-132Hydrophobic Fumed Silica HMDS-TreatedDownloadDownload
HB-139Hydrophobic Fumed Silica PDMS-TreatedDownloadDownload
HB-151Hydrophobic Fumed Silica DDS-TreatedDownloadDownload
HB-152Hydrophobic Fumed Silica DDS-TreatedDownloadDownload
HB-202NHydrophobic Fumed Silica Special Silane TreatedDownload
HB-701Hydrophobic Fumed Silica Special Silane TreatedDownload


Our main products are fumed silica SiO2, fumed titanium dioxide TiO2, and fumed alumina Al2O3. We get 20+ years of expertise and 20,000 tons of annual capacity. We supply total of 23 grades of hydrophilic & hydrophobic fumed silica. We get registration of REACH and pre-registration of K-REACH & KKDIK. We are the leading setting body of ISO18473-1:2015ISO18473-3:2018, and ISO 23157:2021. Learn More About Hifull

Frequently Asked Question

A Manufacturer. Hubei Huifu has been researching and manufacturing fumed silica for 20+ years. We are the largest manufacturer of fumed silica with a well-developed and stable manufacturing process in China.
We get registration of REACH and pre-registration of K-REACH & KKDIK. We get certificates of ISO 9001, ISO 14001. We are the leading setting body of ISO18473-1:2015, ISO18473-3:2018 and ISO 23157:2021.

  • Manufacturer: Leading fumed silica manufacturer in China with 20+ years of expertise, 12,000 tons annual capacity 
  • Registration & Certificate: REACH, K-REACH, KKDIK, ISO9001, HALAL, KOSHER
  • Manufacturer Direct Supply: 23 grades of hydrophilic; hydrophobic fumed silica supplied, good quality, competitive price
  • International Standard: Leading setting body of ISO18473-3-2018 Fumed silica for silicone rubber application; Member of the setting body of ISO18473-1-2015 Nanoscale calcium carbonate for sealant application
  • Technology Expertise: 50+ technology patents experienced R&D team from top universities of China Project 211 & Project 985 

Free Sample: All grades of fumed silica sample available, Contact to Us

Pyrohydrolysi & Trichloromethylsilane

Fumed silica is synthesized by the pyrohydrolysis of silicon tetrachloride or trichloromethylsilane in the flame of hydrogen and oxygen. Our main raw material is silicon tetrachloride, and the secondary is trichloromethylsilane.

Hydrophilic Fumed Silica SiO2:

HL-150 / HL-200 / HL-300 / HL-380 / HL-150W / HL-200W

Hydrophobic Fumed Silica SiO2:

DDS Treated — HB-151/ HB-152 ;
PDMS Treated — HB-139 ;
HMDS Treated — HB-132 / HB-135 / HB-612/ HB-615 / HB-620 / HB-630.

Fumed Titanium Dioxide TiO2: NT-50

Fumed Aluminium Oxide Al2O3: Aluna-80 & Aluna-100

Price is based on the actual grade.

When the price of raw material fluctuates, we may adjust the price accordingly, please enquire before placing orders. Our email: Cell : + 8618571019514

When fumed silica is used as filler or additives, it helps in thickening, reinforcement, transparency, free-flow, thixotropic performance, dielectric properties, anti-settling, heat insulation, and anti-sagging. For example, for powder products, HIFULL fumed silica is used as an anti-caking agent; for liquid products, HIFULL fumed silica is used as an anti-settling agent or suspending agent.

ApplicationsFunctionsRecommended Dosage
Paints & Coatingsrheology & thixotropic control,anti-sagging,anti-settling0.5-2%
UPR, Gel Coatrheology & thixotropic control,,anti-sagging,anti-settling0.5-2%
HTV Silicone Rubberreinforcement15-30%
RTV Silicone Rubberthickening & reinforcing10-20%
Adhesivesrheology & thixotropic control, anti-sagging,anti-settling2-10%
Cable Gelthickening5-10%
Gel Batterythickening0.5-6%
Industrial Powdersanti-caking0.5-1%

Quality Stabilization: we are the earliest fumed silica manufacturers with independent R&D in China, which guarantees our product stabilization.

Largest Manufacturer: Our annual output of fumed silica is about 12,000 tons.

Strong R&D Team: Besides our own R&D institute and application& technology department, we’ve to build a research center with Sichuan University and Wuhan University, both are top-tier universities in China.

Leading Authority: We have already been the influential enterprise in the silicon industry in China. Doctor Wang Yuelin, the actual controller of Hifull, is the leader of the Sino-Germany project ISO18473-3 << Fumed Silica for Silicon Rubber>> and he is granted the Outstanding Contribution Award by the committee.

Mainly T/T, L/C and D/P, actual payment terms please check with sales when placing orders.

We will arrange delivery immediately according to the manufacturing schedule and conditions. Due to shipping schedule or other factors, please check with sales when placing orders.

Still have questions?

If you cannot find an answer to your question in our FAQ, you can always contact us and we will be with you shortly.

Contact Support

Hello, Customers

My name is Van, I’m the business manager of HIFULL, I have been in Fumed Silica Industry for more than 10 years. Feel free to contact me. I’m happy to provide you the best service and products.
Business Manager