FILLIT (CENOSPHERE & CERAMIC MICROSPHERE)
Advanced Hollow Ceramic Microspheres for Lightweight, High-Performance Applications
Cenosphere and Ceramic Microspheres are lightweight, hollow spherical materials widely used as high-performance fillers across oil & gas, construction, paints and coatings, refractory, friction and abrasion, plastics, composites, sealants and other industrial applications.
PETRA FILLIT is a range of lightweight hollow ceramic microspheres designed to reduce material weight and density while improving workability, flowability, thermal insulation, dimensional stability and overall formulation performance.
The unique spherical structure of FILLIT particles provides a ball-bearing effect that improves flow and processing, while their low density, high compressive strength, thermal resistance and chemical inertness make them suitable for demanding industrial applications.
WHAT IS CENOSPHERE?
Cenospheres are lightweight, inert, hollow ceramic spheres generated as a by-product of coal combustion in thermal power plants. They are primarily composed of alumina and silica and contain a hollow interior filled with air or gas.
Their spherical shape, low density and high strength provide buoyancy and allow them to function as lightweight fillers in a wide variety of formulations.
Cenospheres typically range from grey to light grey or nearly white in appearance and can offer excellent thermal and sound insulation, chemical resistance, low water absorption and high temperature resistance.
WHAT IS A CERAMIC MICROSPHERE?
Ceramic Microspheres are hollow, spherical ceramic particles designed to provide a combination of low density, high strength and thermal stability.
PETRA FILLIT Ceramic Microspheres are available in particle sizes ranging from approximately 5–500 microns, depending on grade. Their hollow structure and smooth spherical surface provide excellent flow characteristics and help reduce density while maintaining useful mechanical performance.
FILLIT Ceramic Microspheres are particularly suitable for formulations where lightweighting, thermal insulation, improved processability and dimensional stability are required.
PETRA FILLIT – HOLLOW CERAMIC MICROSPHERES
FILLIT is PETRA’s range of lightweight, high-performance hollow ceramic microspheres developed for industrial applications requiring weight reduction and enhanced material performance.
The combination of:
- Low density
- Hollow spherical structure
- High compressive strength
- High temperature resistance
- Low thermal conductivity
- Chemical inertness
- Thermal and sound insulation
- Excellent flowability
- Reduced shrinkage and warpage
- Reduced shrinkage and warpage
makes FILLIT a multifunctional filler for advanced material formulations.
FILLIT can be incorporated into resins, binders, polymers, coatings, cementitious systems, refractory materials, adhesives, sealants and composite formulations.
PETRA FILLIT – HOLLOW CERAMIC MICROSPHERES
Ultra-Lightweight Filler :- The hollow structure and low density of FILLIT help reduce the overall weight and density of formulated products.
High Compressive Strength :- Despite its lightweight structure, FILLIT offers high compressive strength, making it suitable for applications where both weight reduction and mechanical performance are required.
Spherical Particle Geometry :- The smooth spherical shape provides a ball-bearing effect, improving flowability, workability and processing efficiency.
Thermal Insulation :- FILLIT provides low thermal conductivity and can enhance thermal insulation in coatings, construction materials, refractory systems and industrial composites.
High Temperature Resistance :- FILLIT is suitable for applications exposed to elevated temperatures and can contribute to thermal protection and insulation.
Chemical Resistance :- The ceramic composition provides resistance to many chemical environments and supports use in demanding industrial applications.
Reduced Shrinkage and Warpage :- The spherical filler structure can help improve dimensional stability and reduce shrinkage and warpage in formulated materials.
Sound Insulation :- FILLIT can contribute to sound-dampening performance in selected construction and composite applications.
Low Material Consumption :- Its high packing efficiency and low oil absorption can help reduce resin, binder or water demand in suitable formulations.
FILLIT GRADES
PETRA offers different FILLIT grades designed for specific performance requirements and industrial applications.
1. CEMENTING GRADES – OIL & GAS
| Grade |
Density (g/cc) |
Bulk Density (g/cc) |
Typical Application |
| FILLIT 0.85 H |
0.80–0.85 |
0.35–0.48 |
Cementing slurry, lightweight additive, filler |
| FILLIT 0.85 M |
0.80–0.85 |
0.35–0.48 |
Cementing slurry, lightweight additive, filler |
| FILLIT 0.85 L |
0.80–0.85 |
0.35–0.48 |
Cementing slurry, lightweight additive, filler |
| FILLIT 0.80 H |
0.70–0.80 |
0.32–0.42 |
Cementing slurry, lightweight additive, filler |
| FILLIT 0.80 M |
0.70–0.80 |
0.32–0.42 |
Cementing slurry, lightweight additive, filler |
| FILLIT 0.80 L |
0.70–0.80 |
0.32–0.42 |
Cementing slurry, lightweight additive, filler |
CFILLIT is used in oil-well cementing to reduce slurry density and improve flow characteristics. Selected grades can also be used in applications involving lost circulation control.
2. PAINTS & COATINGS GRADES
| Grade |
Density (g/cc) |
Bulk Density (g/cc) |
| FILLIT 75 |
0.70–0.90 |
0.35–0.48 |
| FILLIT 100 |
0.70–0.90 |
0.35–0.48 |
| FILLIT 125 |
0.70–0.90 |
0.35–0.48 |
| FILLIT 150 |
0.70–0.90 |
0.35–0.48 |
| FILLIT 212 |
0.70–0.90 |
0.35–0.48 |
| FILLIT 300 |
0.70–0.90 |
0.35–0.50 |
| FILLIT 500 |
0.70–0.90 |
0.35–0.50 |
| FILLIT 500 EX |
0.75–0.85 |
0.35–0.50 |
These grades are suitable for paints, industrial coatings, automotive underbody coatings, thermal-insulating coatings, sealants, putties, adhesives, caulks, epoxies, polyurethane systems and advanced construction materials.
3. FRICTION & ABRASION GRADES
FILLIT 500 | 99
FILLIT grades designed for friction and abrasion applications can be used in formulations such as brake pads, brake shoes and insulated boards where lightweight mineral fillers and controlled performance are required.
4. REFRACTORY & FOUNDRY GRADES
| Grade |
Density (g/cc) |
Bulk Density (g/cc) |
| FILLIT 100–500 |
0.80–1.00 |
0.35–0.50 |
| FILLIT 500 | 99 |
0.80–1.00 |
0.35–0.50 |
FILLIT is used in refractory and foundry formulations where low density, thermal insulation, flowability and high-temperature performance are important.
FILLIT IN SYNTACTIC FOAMS
FILLIT hollow ceramic microspheres can be used as fillers in syntactic foam systems.
Their low density helps reduce overall material weight, while their strength and thermal insulation characteristics can contribute to improved performance.
Syntactic materials incorporating hollow microspheres can provide useful resistance to hydrostatic pressure and long-term exposure, making them suitable for selected demanding applications.
PETRA FILLIT – ADVANCED LIGHTWEIGHT FILLER SOLUTIONS
With its combination of low density, hollow spherical structure, high compressive strength, thermal insulation, chemical resistance and excellent flow characteristics, PETRA FILLIT provides a versatile solution for manufacturers seeking lightweight and high-performance material formulations.
From oil-well cementing and industrial coatings to construction materials, refractories, composites, friction materials, adhesives and sealants, FILLIT enables the development of products with reduced weight and optimized performance.
PETRA continues to develop and supply FILLIT grades tailored to diverse industrial requirements, providing reliable lightweight filler solutions for modern material applications.