A Silicon/Phosphorus Synergistic Flame Retardant Polyamide Resin

Abstract

The invention relates to a silicon / phosphorus synergistic flame-retardant polyamide resin, belonging to the field of flame-retardant technology. The mass percentage content is 50% to 98% of polyamide resin, 0.1% to 10% of silsesquioxane (POSS), 1% to 30% of organic phosphinate, 0% to 40% of glass fiber, anti-dripping Falling agent 0% ~ 0.5%, antioxidant 0.1% ~ 2%, according to the appropriate filler ratio, melt blending under certain conditions to obtain a polyamide material with excellent flame retardant properties; the synergistic flame retardant system can be used in less With the added amount, the peak heat release rate, total heat release and smoke production of polyamide are significantly reduced, the limiting oxygen index and vertical combustion level of polyamide are significantly improved, and the problem of melting droplets during combustion is improved. The char layer is dense and complete, and the residual The carbon rate is significantly improved, which has greatly improved the problems of low carbon residue and large smoke production when adding organic phosphinate alone to polyamide. The prepared glass fiber-added flame-retardant chip can be used in the fields of electronic appliances, automobile manufacturing, communication, etc.; the glass-free flame-retardant chip can be used for spinning.

Description

technical field [0001] The invention relates to a silicon / phosphorus synergistic flame-retardant polyamide resin, belonging to the field of flame-retardant technology. Background technique [0002] Polyamide (PA) resin is a class of polymers containing amide groups (-NHCO-) ​​in the main chain. It is the earliest developed, largest output and most widely used variety among the five general engineering plastics. Because of its excellent mechanical properties, self-lubrication, heat resistance, wear resistance, fatigue resistance, solvent resistance, polyamide resin is widely used in electronic appliances, automobiles, mechanical equipment, daily necessities and other fields. [0003] The aliphatic PA resin without flame retardant treatment has poor flame retardant performance due to the large number of methylene structures in the molecular chain. Taking PA6 with the largest output as an example, the limiting oxygen index (LOI) is only about 22%. The combustion level UL94 is...

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Problems solved by technology

However, in recent years, due to the introduction of a series of mandatory environmental protection regulations internationally, the use of halogenated flame retardants has been restricted; (2) nitrogen-based flame retardants are mainly melamine and its derivatives, MCA, MPP However, the amount of the two added is large and there is a phase separation phenomenon with the polyamide resin, which makes it difficult to mix evenly, resulting in a serious decline in the mechanical properties of the matrix; (3) Inorganic flame retardants are represented by magnesium hydroxide and aluminum hydroxide. Although this type of flame retardant has no environmental pollution and low cost, its flame retardant efficiency is low, its addition amount is large, its compatibility with polyamide matrix is ​​poor, and its mechanical properties drop significantly, which seriously restricts the application of this type of flame retardant in high-performance polyamide products. (4) Phosphorus-based flame retardants are mainly organic phosphinates. After being heated, organic phosphinates release inert free radicals to inhibit the spread and development of flames, but in real fire scenes , due to the continuous burning of the material by the flame, the gas-phase flame retardancy will soon fail, and the heat release rate and the total heat release are not ideal (Polymers Journal 2019, Issue 11, Document Number 74; Polymers for advanced technologies journal 2018, Volume 29, Issue 3, 1068-1077), even due to the presence of phosphorus, the amount of smoke produced by the combustion of the substrate increases, which is not very helpful for people to escape from the fire

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