An organic-inorganic hybrid high-efficiency synergistic flame-retardant char-forming agent and its preparation method

Abstract

The invention relates to the technical field of macromolecular flame-retardant char-forming agents applied to polymer materials, and discloses an organic-inorganic hybrid high-efficiency synergistic char-forming agent and a preparation method thereof, whose structural formula is as follows. The char-forming agent undergoes nucleophilic substitution, and p-xylylenediamine replaces the two chlorine atoms on the cyanuric chloride sequentially at different temperatures to form a linear macromolecular trichloride with p-xylylenediamine as a chain extender. The oxazine intermediate, and then increase the temperature, will have been connected to the nano-hydrotalcite and γ-aminopropyltriethoxysilane through the hydroxyl group through the same principle as the substitution of p-xylylenediamine and cyanuric chloride. Made by chlorine substitution on the base. The char-forming agent has the characteristics of good char-forming property, high molecular weight, migration resistance, high temperature resistance, and does not affect the mechanical properties of the matrix material. , the problem of poor char formation performance with complete morphology is applied to thermoplastic polyester elastomers.

Description

technical field [0001] The invention relates to the technical field of macromolecular flame-retardant char-forming agents applied to polymer materials, in particular to a novel organic-inorganic hybrid high-efficiency synergistic flame-retardant char-forming agent and a preparation method thereof. Background technique [0002] Over the past decades, halogenated flame retardants (FRs) have been widely used to limit the flammability of polymeric materials. However, its flame retardant process usually brings many negative effects, such as the generation of corrosive and toxic fumes or volatiles, which can cause great damage to the environment and human health. Therefore, halogen-free flame retardants, especially intumescent flame retardants (IFR), can meet the current requirements of various industries due to their halogen-free, low toxicity, droplet suppression, high flame retardant efficiency and low preparation cost. Due to the needs of personal safety and environmental pro...

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Problems solved by technology

However, EG as an intumescent flame retardant also has the following problems: First, EG has almost no chemical reaction with the polymer, the force between the charcoal layers is small, excessive expansion occurs during combustion, and the charcoal layer formed is often too loose and not dense enough , that is, the so-called "popcorn effect" occurs, and the flame retardant effect may not be as expected; the second is that the expanded carbon residue is observed under a scanning electron microscope and found to be "worm-like", and the gaps between the carbon layers are large and not dense enough. The flame retardant efficiency is not high; the third is that the larger the particle size of EG, the poorer its compatibility with the polymer matrix, resulting in a decrease in the mechanical properties of the material

Although char-forming agents mainly based on triazine derivatives have many advantages over other char-forming agents, they are easy to migrate to the surface of polymers due to small molecular weight and other reasons, and there have always been low flame retardant efficiency, poor thermal stability and formation. The problem of poor carbon performance leads to the inability to form a good-looking carbon layer within the required time, and it is impossible to achieve efficient coordination and coordination of the three sources

As a commonly used inorganic flame retardant synergist, nano-hydrotalcite has a synergistic flame-retardant effect with IFR, but it has poor compatibility with polymers, and it is difficult to uniformly disperse in the polymer matrix, which seriously affects the performance of nano-hydrotalcite and IFR. Synergistic Flame Retardant Effect of IFR in Polymer Materials

The above problems eventually lead to unsatisfactory flame retardant effect

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