Long Term Durability
In 1987 a twenty year old GRP-antenna mast, manufactured in the hand lay up technique, was tested at the test site of Brown Boverie & Cie. Company in Mannheim, Germany. Experts in the field were to determine the extent of deterioration. The results showed that the GRP-antenna mast's supporting laminate had impressively maintained its original condition over a span of twenty years.


UV Light and Weatherability
The mechanical material features will not be affected by UV light due to the exterior protective layers. Only a slight, yet harmless discoloration of the resin's outer layer may occur. Any damage to the glassfibres is prevented by the protective coating.
The coating on the IBK GRP-antenna masts is applied in three applications, which is in accordance with the latest technical standards and has a result of maximum color brilliancy and durability.


Water Absorption of GRP
Like any other plastic, GRP absorbs a minimal amount of water. The pure resin according to the manufacturer's specifications can absorb up to 42 mg according to DIN 53422. Only the resin, not the glass can absorb water. The amount of water absorption into the laminate is minimal.
A great number of GRP-antenna masts are installed in a wide range of climate zones in Europe. There is no evidence to date that small amounts of water have in any way affected the mechanical features. The conditions of the antennas remain the same.


Temperature Influences on GRP
Based on its molecular structure, unsaturated polyester resin has a better resistance to high temperatures when compared to the thermoplastics such as polyvinylchloride, polyethylene and polystyrol, etc...
IBK GmbH uses a polyester resin for its GRP-antenna mast, so that the antenna mast retains a high resistance to heat.
No brittleness nor deterioration of mechanical properties occur when temperatures drop well below -20º C. Temperatures above 80º C cause softening, and break down the strength of the mechanical property. The raw materials used in the IBK factory have proven satisfactory in the range of -40º C up to 80º C.