2018-02-26 09:14:18
The adhesive performance of PTFE tape is influenced by factors like temperature, humidity, chemical medium and ultraviolet ray, especially high temperature, high humidity and ultraviolet ray. When adhesive is exposed in the high temperature environment, certain degradation will happen and mechanics performance will reduced after high temperature test; mechanics performance will reduced after thermal aging, thus influences adhesive performance. Being shone by ultraviolet ray for a long time will lead color fading, embrittlement and even chemical decomposition of tape and also influence the adhesive performance and usage effect.
The adhesive strength of the adhesive will decrease in humid environment because some chemical bonds in the adhesive can easily be hydrolyzed. The chemical structure of adhesive base stock, type and dosage of catalyst and the flexibility of adhesive will affect the speed of hydrolysis. Only when you choose adequately the dosing of base stock and catalyst, can adhesive intensity be improved.
In order to avoid the influence of environmental factors, if the adhesive is used under severe environment, we should make the simulation test of environment, and at the same time, we should also ensure adhesive-bonded joint can bear the effect of external force.
Both the surface roughness and surface profile of covering-and-coating products will exert an influence on the adhesive strength of PTFE tape. During the covering and coating period, time, temperature, pressure and the pollution level of surface all could affect the adhesive property and effect.
For example, low temperature could make the tape become hard and brittle, and aggravate stress concentration. What's more, under low temperature, the tape is easy to deform and can not obtain relatively stable mechanical properties; the tape will be easier to be softened under high temperature, which will reduce the shearing strength.
When you intend to improve the adhesive performance and effect of PTFE Tape and increase its service life, you should reasonably avoid the negative factors in the using process.