LUDOX® Colloidal Silica - A Versatile Tool for Building & Construction
The demand for resilient products from consumers of building materials has increased drastically over the last decade. In order to stay competitive, producers of building materials like concrete, coatings, adhesives, and sealants need to innovate to improve resiliency of their products while also reducing costs. Formulating with LUDOX® colloidal silica provides end products with improved strength and consistency that boost productivity and reduce cost.
Shotcrete & Sprayable Concrete
Traditionally silica fume has been used as a pozzolanic rheology
modifier and binder in sprayable concrete. LUDOX® colloidal silica offers a number of benefit over silica fume when used as a concrete bonding agent. LUDOX® densifies concrete and imparts shotcrete with better cohesive strength than silica fume thus improving sprayability, increasing layer thickness, and reducing rebound. LUDOX® also reduces setting time when compared to silica fume due to a higher surface area and faster hydration. Because it is an aqueous dispersion, LUDOX® can be easily dispersed in concrete without generating any hazardous dust and reduces mixing time and the risk of agglomeration.

Concrete Sealer and Paint

Anticorrosive Pre-Treatment
Chromium based coatings are commonly used to protect metals
Caulks & Adhesives
Caulks and adhesives play a vital role in the long term
Formulation Guidance
LUDOX® colloidal silica vary mainly in particle size, silica content, stabilizing ion, pH, and surface charge. The smaller particle size grades are suited for binding application and the larger particle size grades are better for surface modification. Most grades are stabilized with sodium but there are ammonium stabilized grades available for applications where sodium poses an issue. Positively charged, chloride stabilized grades are also available for formulations with significant levels of cations. Care should be taken to choose a LUDOX® grade that matches the pH of the formulation. Some commonly used grades and their specifications are listed below.Grade | Surface Charge | Silica Content | Counter Ion | Particle Size | pH |
---|---|---|---|---|---|
SM | Negative | 30% | Sodium | 7 nm | 10 |
SM-AS | Negative | 25% | Ammonium | 7 nm | 9.5 |
HS-30 | Negative | 30% | Sodium | 12 nm | 9.7 |
HS-40 | Negative | 40% | Sodium | 12 nm | 9.7 |
AS-40 | Negative | 40% | Ammonium | 22 nm | 9.2 |
TM-50 | Negative | 50% | Sodium | 22 nm | 9 |
CL | Positive | 30% | Chloride | 12 nm | 4 |
Lithium Polysilicate | Negative | 20% | Lithium | N/A | 11 |