Preparation method of expansion-type red phosphorus microcapsule

Abstract

The invention discloses a preparation method of an expansion-type red phosphorus microcapsule. The preparation method comprises the following steps: step one, adding red phosphorus, disodium m-phthalate, and m-phenylenediamine dihydrochloride into a high-pressure reactor, and then sealing the reactor; step two, introducing CO2 into the reactor to eliminate the air in the reactor, then adjusting the inlet / outlet valves to make the CO2 go through the reactor in a small flow, and discharging CO2 from the outlet; step three, heating to a required temperature, starting a stirrer, opening a high pressure pump to supply CO2 to maintain the pressure in the reactor, heating to a required temperature, and then carrying out reactions under a constant temperature for a while; step four, after the reaction, closing the gas inlet vale and the gas outlet valve, opening a nozzle, and rapidly ejecting the reaction products into a collecting apparatus through the nozzle so as to obtain the red phosphorus microcapsules. In the provided preparation method, the red phosphorus microcapsule is prepared through a supercritical reaction cladding method, the capsule wall of the prepared red phosphorus microcapsule is more stable and cannot be peeled off easily, and thus the red phosphorus microcapsule has a good application prospect.

Description

[0001] technical field [0002] The invention relates to a preparation method of an inorganic phosphorus-based flame retardant, in particular to a preparation method of red phosphorus microcapsules. [0003] Background technique [0004] Inorganic phosphorus-based flame retardants are favored by users for their long-lasting flame-retardant effect, good thermal stability, non-volatility, and halogen-free. Because red phosphorus only contains the flame retardant element phosphorus, it has higher flame retardant efficiency than other phosphorus-based flame retardants, but red phosphorus has many disadvantages, such as: volatile in the air, poor compatibility with resins, long-term contact with air and release Toxic gas PH 3 , pollute the environment, easy to be ignited by impact, and the purple red color of red phosphorus is easy to color the flame-retardant products. In order to overcome the above shortcomings, red phosphorus microencapsulation technology came into being. ...

AI Technical Summary

Problems solved by technology

Because red phosphorus only contains the flame retardant element phosphorus, it has higher flame retardant efficiency than other phosphorus-based flame retardants, but red phosphorus has many disadvantages, such as: volatile in the air, poor compatibility with resins, long-term contact with air and release Toxic gas PH 3 , pollute the environment, easy to be ignited by impact, the purple red color of red phosphorus is easy to color the flame-retardant products, etc.