Aging phenomenon of fiberglass furniture

Aging occurs in any material, but the speed of the process is different. Fiberglass furniture is FRP fiber reinforced plastic. When it comes to plastic, the impression is that it is easy to age and has a short service life. When mentioning FRP furniture, some people will think of many corrugated tiles are not durable, and think that fiberglass furniture is not durable and easy to age, but this is not the case in reality. Although fiberglass furniture belongs to the category of plastics, the matrix material it uses - synthetic resin is a thermosetting resin, which is different from thermoplastic resins to which ordinary plastics belong. It has good thermal deformation performance and slow aging. The quality is good, and the service life of fiberglass furniture is very long.

Our country has organized a wide range of experimental research work on the performance aging of fiberglass products. The aging situation mainly occurs in the following environmental conditions:

1. Open air environment

A. Sunlight Ultraviolet rays in sunlight have certain effects on synthetic resins, which can degrade the resin and reduce its strength.

B. Changes in temperature difference Thermal expansion and contraction can cause FRP to fatigue and reduce its strength. If the FRP is poorly made and there are voids and air bubbles inside, it will easily expand under the condition of temperature difference and accelerate the damage of the structure.

C. Wind, rain and frost have a certain erosive effect on the surface of fiberglass furniture.

Through the combination of the above factors, after a certain period of time, the surface of FRP furniture will gradually lose its luster and color, and then the surface resin layer will gradually thin until the glass fibers are exposed. At this time, due to the interface between the glass fiber and the resin, the influencing factors such as moisture can penetrate into the interior of the FRP through this interface, and the aging process is accelerated.

More than ten years of tests by relevant parties have shown that under atmospheric exposure conditions, the mechanical properties of FRP furniture decrease less and slowly. Within ten years, the bending strength and tensile strength can generally remain above 80%. In terms of geographical influence, the aging speed of the humid tropics is faster than that of the temperate and cold regions.

2. Indoor environment

It is basically similar to that in the open air, but due to the lack of sunlight, the appearance of FRP furniture does not change significantly, and the mechanical properties decrease less. This shows that sunlight, wind and rain have a greater impact on the aging process, and the aging resistance of FRP furniture under indoor conditions is the best.

3 water-soaked environment

A. Absorption Due to factors such as resin quality and process operations, bubbles, microcracks, pores, etc. will remain in FRP, which will cause FRP to absorb some water, and the entry of water will affect the performance of FRP.

B. Erosion Under the action of water, the resin will degrade (especially when the curing degree of the resin is insufficient), and the glass fiber in the FRP furniture will be eroded and dissolved under the action of microcracks and interfaces. Under the action of absorption, FRP furniture will increase in weight, and in the case of corrosion, FRP furniture will lose weight. It can be found from the FRP water immersion test that in the initial stage, the mechanical properties of FRP change greatly, but it tends to be stable after three years, and can still maintain this wet strength until ten years later. In the wet strength, the tensile strength can maintain more than 70%, the bending strength can maintain more than 40%, and the impact toughness does not decrease. Interestingly, when FRP furniture leaves water, its strength will gradually rise as the water gradually decreases.