What is the principle of photoinitiator TPO?
August 30, 2022
Light curing system including UVG, UV coating, UV ink, etc., accept or absorb the external energy, itself will occur chemical changes, decomposition into cations, causing polymerization and reaction.
All substances that produce free radicals by light and cause further convergence are collectively called photoinitiators. Some elements absorb photons after light, excited state; The stimulated molecules split evenly out of the elemental base, thus initiating individual polymerization and producing high elements.
Radiation technology is an energy-saving and environmental protection technology of radiation curing such as ultraviolet (UV), electron beam (EB), infrared, visible light, laser, chemical fluorescence, etc. Probability plays a decisive role. The photoinitiator absorbs light energy after light irradiation, splits into two active groups, causes the linkage polymerization of photosensitive resin and diluent, makes the adhesive bond and cure, characterized by fast, environmental protection and energy saving.
What is the selection principle of photoinitiator TPO? Let's analyze it together.
The appropriate photoinitiator TPO was selected according to the type of prepolymer and monomer.
Good solubility and reactivity, less usage, fast efficiency.
To have a certain thermal stability, 85 below the decomposition, long-term storage stability.
Good comprehensive use of a variety of photoinitiators. Reactions may be initiated at different wavelength ranges and therefore faster than a single photoinitiator.
The photoinitiator was used with the amine promoter EDAB.
Small smell, non-toxic, no environmental pollution.
Cheap and easy to get, low cost.
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?
The photoinitiator TPO elemental region (250~400 nm) or visible region (400~800 nm singlet or triplet) undergoes a single element or double element chemical interaction, leading to the initiation of monomer reaction of active fragments, such as positive, anion, etc. According to the mechanism, photoinitiators can be divided into free radical reactive photoinitiators and cationic photoinitiators, which are widely used as free radical reactive photoinitiators.