Polyformaldehyde with low formaldehyde emission and preparation method thereof

Abstract

The invention provides polyformaldehyde with low formaldehyde release amount and a preparation method thereof. A formaldehyde absorbent-amine compound of polyformaldehyde is loaded on the surface of a carboxylated carbon nano tube at a high grafting rate and intercalated between graphene layers, graphene hydrogel is prepared, porous reduced graphene aerogel is obtained after dehydration, and by means of the excellent stabilizing effect, the super-large specific surface area and the strong adsorption capacity of graphene, the porous structure of the aerogel is formed, the adsorption area and the adsorption capacity of the aerogel on harmful gas such as formaldehyde are increased, meanwhile, the intercalated carboxylated carbon nanotubes play a supporting role on the graphene aerogel through self-assembly, and the enhancement effect is achieved; the formaldehyde absorbent grafted on the surface is also beneficial to absorption and removal of formaldehyde; and further the modified graphene aerogel particles are compounded with polyformaldehyde, and processing is conducted by adopting a conventional melt extrusion method to obtain the polyformaldehyde with low formaldehyde emission.

Description

technical field [0001] The invention belongs to the field of polymer material processing, and in particular relates to a polyoxymethylene with low formaldehyde emission and a preparation method thereof. Background technique [0002] The information disclosed in this background section is only intended to increase the understanding of the general background of the present invention, and is not necessarily taken as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to those skilled in the art. [0003] Polyoxymethylene (POM) is [-CH 2 -O-] main chain, unbranched, high melting point, high density, high crystalline thermoplastic engineering plastics, with high strength and rigidity, excellent creep resistance, fatigue resistance, inherent lubricity, wear resistance It is the closest to metal in engineering plastics, and can be used to replace copper, aluminum, zinc and other non-ferrous metals and alloy products. It is widel...

AI Technical Summary

Problems solved by technology

[0004] Due to the special molecular structure of POM, its thermal stability is poor, especially in the process of processing, production and application, the unstable hemiacetal end group formed in the synthesis is easily decomposed by heat, releasing toxic and harmful volatile substances such as formaldehyde. Volatile organic compounds (VOC), not only pollute the environment and endanger human health, but also lead to the deterioration of material properties, seriously affecting its practical application effect

Some studies have prepared a polyoxymethylene material with low formaldehyde emission by compounding triethanolamine devolatilizer, antioxidant, light stabilizer, melamine formaldehyde capture agent and magnesium oxide formic acid absorbent and other additives in the polyoxymethylene material. There are researches that adopt the melt extrusion method to carry out terminal group stabilization treatment to polyoxymethylene, and have studied the influence of basic catalyst, extruder devolatilization ability and temperature on the terminal group stabilization effect in the stabilization process, and show that basic catalyst can Catalytically accelerates the decomposition of unstable end groups and improves the effect of end group stabilization. The stronger the extruder’s devolatilization ability, the more conducive to the rapid removal of formaldehyde and the better the end group stabilization effect. Excessively high processing temperature will cause molecular hostility. Chain breakage, too low is not conducive to the rapid decomposition of unstable end groups

Research in Japan has reported that ammonia solution is used to treat POM raw materials for a long time or at 100-200°C and under high pressure. This is not only time-consuming, but also requires special equipment, and also increases the process of POM cleaning, purification and drying.