Just as heat can destroy adhesives and sealants, so can light. Ultraviolet light, the same type that causes sunburn, can initiate chemical reactions in polymers, which result in their breakdown and loss of chemical and physical properties.  

Consequently, adhesives and sealants used outdoors frequently require UV protection. There are two different classifications of light stabilizers: Ultraviolet light absorbers (UVAs) and Hindered amine (or amide) light stabilizers. Often hindered amines and UVAs are used together to provide a level of stability, which is higher than what would be provided by using either type of stabilizer by itself. Such combinations are effectively used in many adhesives.  

Ciba Specialty Chemicals offers a broad range of stabilizers for use in adhesives and sealants.