These microscopic glass spheres added to resin systems make a lightweight, easy-to-sand putty for minor surface filling of cracks, holes, etc. Used in lower concentrations, they "extend" resin by fluffing it up and reducing shrinkage, they also have extraordinary compressive strength. They differ from "Q-Cell" in that microballoons are more consistent in size, they are considerably stronger and they DO NOT absorb water like Q-Cel. (Color: White)
Performance Enhancements 3M Glass Bubbles offer performance and processing advantages that go far beyond lightweighting. The inherent properties of these microspheres provide a number of unique potential enhancements to help you meet specific requirements – and expand design freedom in a wide variety of applications.
Dimensional Stability 3M glass bubbles can reduce shrinkage and warpage in plastics, spackling compounds, wood composites and other materials – helping to reduce rejects and reprocessing. They allow high filler loading, which can improve part stiffness and dimensional stability, and allow the molten polymer to cool homogenously, helping prevent sink marks and uneven solidification. Plus, 3M glass bubbles provide more uniform stress distribution to help prevent warpage in plastics filled with high aspect ratio fillers.
Weight Reduction 3M Glass Bubbles are used to reduce weight in applications from plastics, thermosets and sheet- or bulk-molded composites to structural foams and elastomers. 3M Glass Bubbles iM16K, for example, enable weight reductions of 15% or more in many polypropylene systems, and 18% or more in glass fiber-filled polyamide parts. All without requiring significant material or process changes, and without compromising the mechanical the integrity of the finished product. The resulting lighter-weight parts not only have greater consumer appeal, but can also contribute to environmental sustainability through better fuel economy.
Productivity & Cycle Time In injection molding and extrusion processes, low-density 3M glass bubbles displace mass that would otherwise, need to be heated or cooled. As a result, glass bubble-filled resins cool faster – helping manufacturers produce more parts per hour while achieving weight reduction targets. Cooling time reductions of up to 15–25% have been reported in production-scale use.
Sustainability The benefits of lightweighting have an obvious impact in the transportation sector, but customers across many industries can benefit from the lower cost of shipping lightweight parts. In addition, some plastics made with 3M glass bubbles may be recyclable, and can be re-ground as many as five times with minimal change in properties. The glass bubble fraction of these plastics raises few, if any, issues during disposal, because they are made from an inert glass.
Thermal Insulation The addition of 3M Glass Bubbles to a resin the system can decrease thermal conductivity, depending on the grade and amount of microspheres used. The low thermal conductivity of 3M glass bubbles make them ideal for use in thermally insulating syntactic foams for deepsea applications. Another potential applications include “cool-touch” steering wheels and other interior automotive components subject to heating by the sun, and interior paints that help reduce condensation in moist environments.
Water Resistance 3M glass bubbles are made of soda-lime borosilicate, which is a true glass with inherently greater water resistance than borosilicate glass bubbles (water glass). 3M glass bubbles maintain integrity even when boiled in water for more than 40 minutes—whereas borosilicate glass (Q-Cel) bubbles dissolve.
Buoyancy Their combination of high strength and low density has made 3M glass bubbles a “go-to” additive for syntactic foams used in buoys and buoyancy modules. These foams can help prevent a drill riser casing from collapsing under its own weight at depth; on ROVs, they allow for high net buoyancy rated to any ocean depth. In other applications, 3M glass bubbles have been used to make rubber fishing boots and other articles light enough to float.
Nail and Screw Acceptance Wood/polymer composites can be harder to work with than real wood, because it is difficult for nails and screws to penetrate the dense polymer. The addition of 3M glass bubbles provides a greater void volume: the glass bubbles break when a screw or nail is driven into the composite. This makes the material more easily “nail-able,” like real wood—so it takes less time and less pressure to nail or screw into composite decking.
Machinability and Sandability Parts or tooling compounds containing 3M glass bubbles can often be easier to cut, sand, machine and shape. They also provide better surface definition and render sharper contours and corners in extruded profiles. Glass bubble-filled autobody filler is easier to file and sand with less gouging, and with less clogging of tools.
Dielectric Constant The hollow nature of 3M glass bubbles give them a low dielectric constant, making them useful for producing lightweight materials with desired electrical properties. Applications include printed circuit boards, radomes and packaging materials
Antilock & Permeability When used as anti blocking agents, 3M glass bubbles can help create space between film layers to prevent them from adhering to each other. And because 3M glass bubbles are made of inorganic glass, they will not absorb penetrant molecules—helping reduce the overall permeability of materials to which they are added.
Harmonics The addition of 3M glass bubbles can reduce noise and vibration, helping improve the harmonics of the finished part.
Solar Reflectivity The spherical shape of 3M glass bubbles reflect light effectively in all directions. They're unique optical properties may make 3M glass bubbles useful for producing light diffusing panels and solar reflective films, building materials, paints and coatings. Potential applications include greenhouses, exterior walls, roof coatings, or outdoor storage or refrigerated tanks.
Surface Appearance Class A paintable surface finishes have been successfully achieved using 3M glass bubbles with smaller particle sizes. Other grades of 3M glass bubbles can be used to deliver custom aesthetic effects such as translucency, gloss control in coatings, or “pebble finish” texturing on appliances and electronics. The hollow nature of glass bubbles also causes light to scatter, delivering a clean-looking white surface at a lower weight than titanium dioxide (TiO2).