Bonding of Glass and Ceramics

Adhesive bonding of glass is usually much more desirable than using mechanical fastening, and gives bonds with good appearance and low stress points. Glass is usually bonded to itself or to metals. The commonest adhesives used are polyurethane, epoxy and UV acrylics. 

For applications requiring optically clear adhesives, the development of UV-cured acrylics has been a major development. These adhesives are widely used in the manufacture of stemware, bonding rear view mirrors, and the general assembly and repair of glass objects. 

Needle bonding has long been a major application for adhesives. The bonding of stainless-steel needles in glass syringes that are prefilled with pharmaceuticals was traditionally done using heat-cured two-component epoxies, but toughened UV acrylic adhesives have led to dramatic increases in productivity. 

Ceramics can often be bonded with epoxy or acrylic adhesives, but there are limitations in their use at high temperatures. Few organic adhesives can perform 250 °C, and inorganic adhesives have been developed for ceramics that offer a service temperature of 2000 °C. These are based on inorganic binding compounds such as sodium silicates and various metal phosphates, with carbon, alumina, silica, magnesia or zirconia powder fillers. Ceramic adhesives can be 

One-component adhesives will cure slowly by drying or can be heated to speed-up the process. Versions where cure is accelerated by atmospheric moisture are also available. The weaknesses of inorganic adhesives include brittleness, sensitivity to moisture, and often lower adhesive strength than their organic counterparts. 

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