Principle of photoinitiator TPO

Photoinitiator TPO is another important component of UV-curable coatings, which is one of the keys to the rapid curing of UV-curable coatings. In 1967, German buyers industrialized UV curing technology, leading to the concept of photoinitiator TPO. Active intermediates that absorb radioactivity, undergo chemical changes, and initiate polymerization are photoinitiators. Its basic characteristics are: in the ultraviolet (uv) interval (200-420 nm) has certain absorption ability, directly or indirectly absorb light, after moving from the ground state to the excited state, active until stimulus triplet, after a single molecule or molecular chemistry, can produce monomer polymerization by active fragments (active), such as free radical, Yang, anion free radicals or ion.

What is the research status of photoinitiator TPO? Let's take a quick look at it.

According to the production fragments of photoinitiator TPO, photoinitiators can be divided into free radical photoinitiators, ionic photoinitiators and anionic photoinitiators. In fact, at present, only the free radical photoinitiator and ionic photoinitiator are industrialized, but in our country, the free radical photoinitiator is mainly used, ionic photoinitiator is not highly industrialized, so the free radical photoinitiator studies are much. The research of free radical polymerization photoinitiator has a long history and a wide variety, mainly containing chromophore compounds, especially with benzene ring linked compounds containing carbonyl groups, mainly including benzene incense and derivatives, acetophenones, aromatic ketones, acetylene oxide, etc.

What is the selection principle of photoinitiator TPO? Let's analyze it together.

1. Select the appropriate photoinitiator TPO according to the type of prepolymer and monomer. 2. Good solubility and action, less usage, fast efficiency. 3. There should be a certain thermal stability, no decomposition below 85, long-term storage stability. 4. Comprehensive use of a variety of photoinitiators. It is possible to initiate action in different wavelength ranges, so the speed is faster than that of a single photoinitiator. 5. Use photoinitiator with amine promoter EDAB. 6. Small smell, non-toxic, no environmental pollution. 7. The price is cheap and easy to get, and the cost is low.

The ideal photoinitiator TPO should have the following advantages, what are they? Let's analyze it together.

(1) Cheap, simple synthesis. (2) The photoinitiator and its photolysis products should be non-toxic. (3) Good stability, easy for long-term storage. (4) The absorption spectrum of the photoinitiator should be consistent with the emission spectrum of the radiation light, and the molar extinction coefficient is higher. (5) Most photoinitiators jump to singlet state and interseries triplet state after absorbing light, so the interseries hopping efficiency of the initiator needs to be accelerated. (6) High start-up efficiency.

What is the principle of photoinitiator TPO? Let's take a brief look at it.

Photoinitiator TPO elemental region (250~400 nm) or visible region (400~800 nm singlet or triplet), after experiencing single element or double element chemical interaction, can lead to the monomer interaction of active debris, such as positive, anion, etc. According to the occurrence mechanism, photoinitiators can be divided into free radical reaction photoinitiators and cationic photoinitiators, which are widely used as free radical action photoinitiators.