Description of Catalyst Poisoning

2021-11-10   Pageview:289

Certain chemicals can poison the catalyst. For example, organic or inorganic substances containing phosphorus, sulfur, lead, mercury, arsenic and halogens are very destructive to the catalyst and will cause permanent deactivation of the catalyst and will not restore activity.

 

 

 

 

 

 

 

 

 

 

 

Rub the surface of the coating film with No. 00 polishing paper to visually check the slip resistance: second, best, and worst.

Under the same test conditions, adding PMMA particles containing UV absorbers in Examples 1 and 2 anti-skid varnishes, compared to the control sample, the anti-skid properties are significantly improved, especially the PMMA with a large particle size, the anti-skid properties are better. It can also be seen that the ability of the coating film to absorb ultraviolet radiation is greatly improved.

Based on the above examples, it is shown that the particle size and the micronized wax emulsion amount of the two types of anti-slip agents have a greater impact on the anti-slip properties of the coating film. If the particle size is too large or the amount of people added is too large, after coating, it will protrude too much on the surface. Although the slip resistance is good, it has a rough feeling and an uncomfortable appearance. The coating film is also prone to bubbles, which affects The adhesion of the coating film. If the particle size is too small, it will be buried in the coating film, unable to exert its anti-slip effect. If the amount of anti-slip agent added is too small, the surface cannot be formed with sufficient roughness, and it is difficult to impart the required anti-slip properties to the coating film. Therefore, according to the coating system used and the required degree of anti-skid, the appropriate anti-skid agent variety, particle size and appropriate amount of anti-slip agent should be selected by experiment. Generally speaking, lower coating thickness, higher content of anti-slip agent and smaller particle size of anti-slip agent can easily obtain better anti-slip performance.

Comparison of the effects of two types of anti-slip agents
Inorganic anti-slip agents are cheap and easy to obtain, but most of their shapes are angular and relatively dense. They tend to block the nozzles during spray coating, making spray application difficult. Moreover, the relative density of the anti-slip agent is much greater than the relative density of the coating (for example, the relative density of sand is 2.5~2.6), and it is easy to precipitate in the coating, and it is difficult to maintain the uniform distribution of the anti-slip agent after coating, especially when the viscosity of the coating itself is low. more serious. In addition, the adhesion of inorganic anti-skid agents to the coating base material is poor, easy to fall off, hard and brittle, and the edges and corners of the coating are easily ground under the action of walking and other external forces, so the gap between the coating film and the second surface is reduced. The number of bonding contact points reduces the friction and coefficient of friction, and reduces the anti-skid effect.

*
*

Leave a message

Contact Us
Your name(optional)

* Please enter your name
* Email address

Email is required. This email is not valid
* How can we help you?

Massage is required.
Contact Us

We’ll get back to you soon

Done