How to Measure the Hydrophobicity of Hydrophobic Fumed Silica

Here are three hydrophobic fumed silica products:

which have been modified by different treating agents, They are all hydrophobic products. How do we compare their degree of hydrophobicity?

Contact angle helps us

  • Contact angle, θ (theta), is geometrically defined as the angle formed by a liquid at the three-phase boundary where a liquid, gas, and solid intersect
  • The larger the contact angle is, the better its hydrophobicity
  • First compress and prepare samples of HB-132, HB-139, and HB-151 respectively, Place them on the Contact Angle Analyzer
  • Then precisely drop liquid onto the surface of the sample, The contact angle will show on the analyzer
  • Drop three times each, Calculating the average numerical value of three results
  • We get the final contact angle for each hydrophobic fumed silica

Their contact angle results rank

Contact Angles of Different Grades of Hydrophobic Fumed Silica

GradesFirst ResultSecond ResultThird ResultAverage Value
HIFULL HB-139126.6°125.3°127.5°126.5°
HIFULL HB-132122.1°121.6°123.1°122.3°
HIFULL HB-151120.3°121.1°120.9°120.7°

This means HIFULL HB-139 obtains the best hydrophobicity among these three products

Related Products

HIFULL® HL-450 (BET=450㎡/g)

HIFULL® HL-450 (BET=450㎡/g) HL-450 Hydrophilic Fumed Silica HL-450 is hydrophilic fumed silica synthesized from the hydrolysis of high purity chlorsilane in a flame of oxygen and hydrogen at temperature over…

HIFULL® HL-260 (BET=260㎡/g)

HIFULL® HL-260 (BET=260㎡/g) HL-260 Hydrophilic Fumed Silica HL-260 is hydrophilic fumed silica synthesized from the hydrolysis of high-purity chlorine in a flame of oxygen and hydrogen at temperature over 1000℃…

HIFULL® HL-90 (BET=100㎡/g)

HIFULL® HL-90 (BET=100㎡/g) HL-90 Hydrophilic Fumed Silica HL-90 is hydrophilic fumed silica synthesized from the hydrolysis of high-purity chlorine in a flame of oxygen and hydrogen at the temperature over…

HIFULL® HL-380 (BET=400㎡/g)

HIFULL® HL-380 (BET=400㎡/g) HL-380 Hydrophilic Fumed Silica HL-380 is hydrophilic fumed silica with a specific surface area of around 400m2/g. Mainly Applied in Coatings & Paintings, Silicone rubber, UPR, Adhesives…

HIFULL® HL-300 (BET=300㎡/g)

HIFULL® HL-300 (BET=300㎡/g) HL-300 Hydrophilic Fumed Silica HL-300 is hydrophilic fumed silica with a specific surface area of around 300m2/g. Mainly Applied in Coatings, Silicone rubber, Thin Film, Adhesives, and…

HIFULL HL-200W (BET=200㎡/g)

HIFULL HL-200W (BET=200㎡/g) HL-200w Hydrophilic Fumed Silica HL-200W is hydrophilic fumed silica with a specific surface area of about 200㎡ /g, countertype to international brand, free sample available for test…

HIFULL® HL-200 (BET=200㎡/g)

HL-200 is hydrophilic fumed silica with a specific surface area of about 200㎡ /g, countertype to an international brand, and a free sample available for testing. Good quality, competitive price,…

HIFULL HL-150W (BET=140㎡/g)

HIFULL HL-150W (BET=140㎡/g) HL-150W Hydrophilic Fumed Silica HL-150W is a Hydrophilic Fumed Silica with a specific surface area of around 140 m2/g to 160 m2/g. Mainly Applied in HTV and…

HIFULL® HL-150 (BET=150㎡ /g)

HIFULL® HL-150 (BET=150㎡ /g) HL-150 Hydrophilic Fumed Silica HL-150 is a Hydrophilic Fumed Silica with a specific surface area of around 150m2/g. Mainly Applied in HTV and RTV Silicone rubber,…

Hubei Huifu Nanomaterial Co., Ltd. manufactures more than 10 grades of fumed silica, both hydrophilic and hydrophobic. We get ISO, REACH, and participate in setting ISO18473-3-2018, ISO18473-1-2015, and ISO23157. We are strong in R&D product quality and factory capacity. Feel free to contact us by email:


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