3M™ Glass Bubbles D32/4500

3M™ Glass Bubbles D32/4500 have methacrylato chromic chloride surface treatment.

• The chemical properties of 3M™ Glass Bubbles D32/4500 resemble those of a soda-lime-borosilicate glass.

Conductivity:

• Conductivity increases with temperature and product density.
• The thermal conductivity of a composite will depend on the matrix material and volume loading of 3M™ Glass Bubbles D32/4500.

Stability:

• Appreciable changes in bubble properties may occur above 1112°F (600℃) depending on temperature and duration of exposure.

pH:

• Because 3M™ Glass Bubbles D32/4500 is a dry powder, pH is not defined.
• The pH effect will be determined by the alkalinity as indicated above.
• When 3M™ Glass Bubbles D32/4500 is mixed with deionized water at 5 volume percent loading, the resulting pH of the slurry is typically 9.1 to 9.9, as measured by a pH meter.

Dielectric Constant:

• The dielectric constant of a composite will depend on the matrix material and volume loading of 3M™ Glass Bubbles D32/4500.

Hard Particles:

• No hard particles (e.g., glass slag, flow agent, etc.) greater than U.S. number 40 (420 microns) standard sieve will exist.

Sieve Analysis:

• Using a 10 gram sample on a U.S. number 200 sieve (74 microns), a maximum of three percent by weight glass bubbles will be retained on the sieve.

Flowability:

• 3M™ Glass Bubbles D32/4500 remain free flowing for at least one year from the date of manufacture if stored in the original, unopened container in the minimum storage conditions of an unheated warehouse.

• To help ensure ease of storage and handling while maintaining free flowing properties, 3M™ Glass Bubbles D32/4500 have been made from a chemically stable glass and are packaged in a heavy duty polyethylene bag within a cardboard container.
• Minimum storage conditions should be unopened cartons in an unheated warehouse.
• Under high humidity conditions with the ambient temperature cycling over a wide range, moisture can be drawn into the bag as the temperature drops and the air contracts.
• The result may be moisture condensation within the bag.
• Extended exposure to these conditions may result in "caking" of the 3M™ Glass Bubbles D32/4500 to various degrees.

To minimize the potential for "caking" and prolong the storage life, the following suggestions are made:

1. Carefully re-tie open bags after use.
2. If the polyethylene bag is punctured during shipping or handling, use this bag as soon as possible, patch the hole, or insert the contents into an undamaged bag.
3. During hot and humid months, store in the driest, coolest space available.
4. If controlled storage conditions are unavailable, carry a minimum inventory, and process on a first in/first out basis.

Dusting that may occur while handling and processing can be minimized by the following procedures:

1. For eye protection wear chemical safety goggles.
2. Use appropriate ventilation in the work area.
3. Pneumatic conveyor systems have been used successfully to transport 3M™ Glass Bubbles D32/4500 without dusting from shipping containers to batch mixing equipment.

• Static eliminators should be used to help prevent static charges.
• Diaphragm pumps have been used to successfully convey 3M™ Glass Bubbles D32/4500.
• Vendors should be consulted for specific recommendations.

3M™ Glass Bubbles D32/4500 breakage may occur if the product is improperly processed.

To minimize breakage, avoid high shear processes such as high-speed Cowles™ Dissolvers, point contact shear such as gear pumps or 3-roll mills, and processing pressures above the strength test pressure for each product.