A detailed solution and solution to the yellow problem of PVC pipe

A detailed solution and solution to the yellow problem of PVC pipe

The main reason is that the dosage of stabilizer is not enough or the grade is not good, there should be the phenomenon of redness.

It is possible to use a stabilizer with a particularly poor quality.

However, most of the problems are caused by the lubrication imbalance, the lubrication is too little, especially the outer slide is too little, the plastic causes the pipe material to change color, and the crisp...

Can add titanium white powder, see if can be able to cover, do not have the words to try to add stabilizer or replace, if be calcic zinc stabilizer more should pay attention to the adjustment of slippery agent.

In addition, the lubricant affects the plasticizing, calcium carbonate is added the whitening agent and so on, as well as PVC resin, other things equal, with PVC will become more bad, need more of the stabilizer.

In general, the problem of stabilizer is to be considered, in fact, it is very important to lubricate the stability.

In addition, if calcium powder is dampened, it will also affect plasticization.

Stabilizers are generally considered first, but the problem can usually be solved by adjusting the lubrication system properly.

The problem of stabilizer is eliminated, the key adjustment agent, dynamic balance.

The stabilizers mentioned in the industry generally do not contain antioxidants.

But calcium and zinc stabilizers generally contain antioxidants.

The base color of the rutile type is reddish, while the base color of the ruiti type is bluish.

Rutile is better, but more expensive.

Whether it is rutile or ruiti titanium dioxide, in the range of visible wavelength (400-700nm), they have high reflectance of light and therefore have good whiteness.

However, the performance of the two different types of titanium white powder showed a significant difference in the wavelength range of ultraviolet light, which is less than the visible range of 300 to 400 nanometers.

For rutile titanium dioxide (red line) in highly damaging UV - (350-400 nm) within A band of UV reflectance is far lower than it blue sharp titanium type titanium pigment, in other words, it to ultraviolet absorption is greatly higher than blue titanium sharp type titanium dioxide.

In this case, the amount of uv light to be Shared with the surrounding organic resin is much less, and the life span of these organic compounds will be long.

And that's why we usually call it a lot of the weather-resistant properties of rutile titanium, which are inherently good.

In extrusion, the base color of the titanium white powder affects the color of the product. In the later use, the different effects of titanium dioxide on uv absorption affect its color.

Actually, rutile type titanium white just than sharp titanium type slightly yellow not turn yellow, the problem is stabilizer was more likely, it is possible that the use of the composite stabilizer, the current domestic some manufacturer of composite stabilizer added a large amount of lubricant to reduce cost, reduce the dosage of effective components, stability is slightly less than under the same weight.

Temperature is too high, mold compression ratio is too large, stabilizer adding quantity is not enough, lubrication system has a problem, the stability of the resin itself insufficient, calcium powder, the screw with a nitrogen-treated barrel clearance problems, cut is too big, for many reasons, have to screen according to actual condition!!!!!

Problem solving:

Add 0.1 stearic acid to promote plasticization

And 0.3 part of titanium white powder mainly to cover the background color problem

The tubes are white and red