5. Conclusion

Glass microsphere manufacturing technology is constantly evolving to meet increasingly stringent application specifications.

• The highest possible ratio of mechanical strength to density to give syntactic foams hydrostatic compressive strength and maximum buoyancy. Future generations of glass microspheres, for example, will be able to withstand pressures > 30 MPa for a real density of .30 g/cm ³ .

• High compressive strength for very deep syntactic foam applications.

• Surface treatment of glass microspheres to guarantee performance and durability of immersed materials.

• Evolution of glass chemical compositions to achieve improvements in physical and chemical performance.