Polymer additive, preparation method thereof and polymer composition containing polymer additive

Abstract

The invention provides a polymer additive, a preparation method thereof and a polymer composition containing the polymer additive, and the preparation method comprises the following steps: carrying out free radical reaction on a hypophosphite aqueous solution and an antioxidant with ethylene in the presence of an initiator to obtain a diethyl phosphinate aqueous solution; mixing the diethyl phosphinate aqueous solution, the metal salt aqueous solution and the alkali liquor, and reacting under the condition that the pH value is 3.5-3.8 to obtain diethyl phosphinate metal salt slurry; mixing and stirring the diethyl hypophosphorous acid metal salt slurry and a flocculating agent to obtain a diethyl hypophosphorous acid metal salt flocculate, filtering, washing and drying to obtain the polymer additive. Through the design of the preparation method, the polymer additive with low acid value and high thermal stability can be obtained, the polymer additive is used as a flame retardant to prepare a polymer composition, injection mold scale can be reduced, the polymer composition has fewer water boiling precipitates, and the stability of the polymer composition under damp and hot conditions is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of flame retardants, and particularly relates to a polymer additive and a preparation method thereof, and a polymer composition containing the same. Background Art

[0002] Dialkyl phosphinate is a general halogen-free and environmentally friendly flame retardant with the characteristics of good flame retardancy, small addition amount, and little effect on the physical and electrical properties of the base resin. More importantly, materials using dialkyl phosphinate as flame retardant have the characteristics of high CTI (relative tracking index) and small smoke emission during combustion. At the same time, they have excellent mechanical and electrical properties, and are increasingly favored by manufacturers in the electrical and electrical industry, with very broad market prospects.

[0003] With the widespread application of dialkyl phosphinates, people gradually discovered that they have performance defects that cannot be ignored. For example, Braun U et al. found that when dialkyl phosphinates are used to flame retard PBT and polyamide, dialkyl phosphinates will decompose into dialkyl phosphinates during high temperature. In particular, when dialkyl phosphinates are used to flame retard polyamide, polyamide has more polar amide groups, which makes polyamide easier to absorb water and has a higher water absorption rate. For example, the water absorption rate of PA66 resin can reach 2.7% under the conditions of 23°C and 50% humidity. During the high-temperature processing of extrusion or injection molding, dialkyl phosphinates themselves have a certain acidity, and the heating process will also decompose dialkyl phosphinate acidic substances, which can easily promote the decomposition of the system and lead to a large amount of gas in the processing process. In the process of repeated injection molding, serious mold scale often appears on the mold, which not only seriously affects the appearance of the product, but also requires frequent cleaning of the mold, resulting in low production efficiency, making it difficult for the product to be better promoted and used.

[0004] At present, the main method to solve the mold scale problem in injection molding of dialkyl phosphinate flame retardant polyamide materials is to add an acid absorber to the system to reduce the acidity of the system. For example, 0.15-1wt% of calcium oxide is added to the halogen-free flame retardant polyamide composition disclosed in EP2417191A1, which neutralizes with some acidic substances in the system, reduces the acidity of the system, reduces the decomposition of the matrix resin, and effectively reduces the corrosion to the mold during high-temperature injection molding; although this method is helpful to reduce mold scale, calcium oxide is easy to absorb moisture, resulting in a high water absorption rate of the system, which is difficult to control during processing.

[0005] In the halogen-free flame-retardant thermoplastic polyamide composition disclosed in CN112409786A, a certain amount of ethylene copolymer is added as an adsorbent to reduce the amount of mold scale generated during the injection molding process. In the halogen-free flame-retardant polyamide composite material disclosed in CN114874616A, a composite system of metal oxides and polyhydroxy components is introduced, and the prepared polyamide material has better yellowing resistance, lower mold scale, and more continuous mold opening and closing times. Although the above methods have a certain improvement effect on the mold scale of dialkyl phosphinate flame-retardant polyamide, they all improve the acidity of the system and reduce the mold scale by adding additives. While increasing the cost, it is difficult to avoid the impact of new substances on other properties of the flame-retardant polyamide, such as the addition of inorganic metal oxides, which will cause the mechanical properties of the material to be reduced. Moreover, the heat resistance of dialkyl phosphinate itself is insufficient, and there will be obvious weight loss at a high temperature above 300°C, which will cause it to decompose during the processing of melt blending, extrusion, etc., affecting the performance; and the method of adding additives does not fundamentally solve the problem of insufficient heat resistance of dialkyl phosphinate.

[0006] Therefore, it is an urgent problem to be solved in the current art to provide a flame retardant additive with lower acidity and better thermal stability so that the polymer composition using the flame retardant additive has lower mold deposit and less additive precipitation. Summary of the invention

[0007] In view of the deficiencies in the prior art, the object of the present invention is to provide a polymer additive and a preparation method thereof, and a polymer composition containing the same. By designing the raw materials, process steps and parameters in the preparation method and their interaction, a polymer additive with low acid value and high thermal stability can be obtained. The polymer additive is used as a flame retardant to prepare a polymer composition, which not only effectively reduces mold deposit, but also makes the polymer composition have a lower content of water-boiling precipitates, thereby extending its service life under hot and humid conditions.

[0008] To achieve this object, the present invention adopts the following technical solutions:

[0009] In a first aspect, the present invention provides a method for preparing a polymer additive, the preparation method comprising the following steps:

[0010] (1) a hypophosphite aqueous solution and an antioxidant react with ethylene in the presence of an initiator to obtain a diethylphosphinate aqueous solution;

[0011] (2) mixing the diethylphosphinate aqueous solution, the metal salt aqueous solution and the alkali solution, and reacting them at a pH value of 3.5-3.8 to obtain a diethylphosphinate metal salt slurry;

[0012] (3) mixing the diethylphosphinate metal salt slurry and a flocculant, stirring to obtain diethylphosphinate metal salt flocs; filtering, washing and drying the diethylphosphinate metal salt flocs to obtain the polymer additive.

[0013] The present invention has found that by adding an antioxidant during step (1), the water-soluble acid value and organic acid value of the product can be effectively reduced. The reason is that the reaction between hypophosphite and ethylene is generally carried out under the initiation of a free radical initiator. Hypophosphite contains a PH bond and has a strong reducing property. Therefore, the free radical reaction and the oxidation reaction exist simultaneously in step (1). The present invention introduces an antioxidant, which can donate electrons to the oxidant, thereby reducing it to a relatively stable substance; at the same time, the free radical reaction between hypophosphite and ethylene is a strong exothermic reaction, which is prone to uncontrollable phenomena during the production process and produces more side reactions. The antioxidant captures free radicals in the form of reacting with free radicals and neutralizes their activity, which can effectively slow down the exothermic effect and reduce the occurrence of side reactions, making the production process controllable.

[0014] Furthermore, the present invention has found through research that the pH of the reaction system has a great influence on the crystallization behavior of the additive precipitation process, thereby affecting the acid value of the product. The present invention controls the pH value of the system in step (2) to be 3.5-3.8, for example, it can be 3.52, 3.55, 3.58, 3.6, 3.62, 3.65, 3.68, 3.7, 3.72, 3.75, 3.78, etc.; within this range, the polymer additive with excellent performance can be prepared, especially with low acid value and excellent heat resistance, and when it is used as a flame retardant to prepare composite materials, it has lower mold scale and water boiling precipitate content. If the pH value of the reaction system in step (2) is too low, it is easy to cause the acidity of the polymer additive to be too high and the thermal stability to be reduced; if the pH value of the reaction system is too high, it will also cause the acid value of the polymer additive to increase, and the continued increase in pH will also lead to a decrease in yield.

[0015] In addition, the main function of the flocculant is to use the groups with positive (negative) charges and some particles or granules with negative (positive) charges in water that are difficult to separate to get close to each other, reduce their potential, make them in an unstable state, and use their polymerization properties to concentrate these particles and separate them by physical or chemical methods. When the flocculant is used for flocculation of the polymer additive of the present invention, the surface of the polymer additive particles is fixed on the molecular chain of the flocculant through adsorption bridging and enhancement, forming a polymer bridge, so that the particles form a collective and settle. The flocculant adsorbs and combines the diethylphosphinate metal salt in the slurry obtained in step (2), which can effectively improve the filtering and washing effect of the polymer additive, and at the same time can reduce the acidity of the polymer additive after filtering and washing.

[0016] In summary, the present invention specially designs a preparation method for a polymer additive. By using an antioxidant and a flocculant in the preparation process and controlling the pH value in the double decomposition reaction process to 3.5-3.8, a polymer additive with a low acid value and excellent thermal stability is prepared. When the polymer additive is used as a flame retardant to prepare a polymer composition, it can significantly reduce mold deposit, so that the polymer composition has a lower content of water-boiling precipitates, greatly improving the stability of the polymer composition under wet and hot conditions and extending the service life.

[0017] The following are preferred technical solutions of the present invention, but are not intended to limit the technical solutions provided by the present invention. Through the following preferred technical solutions, the objectives and beneficial effects of the present invention can be better achieved and realized.

[0018] Preferably, the hypophosphite comprises sodium hypophosphite and / or potassium hypophosphite, and an aqueous solution of sodium diethylphosphinate and / or potassium diethylphosphinate is obtained therefrom.

[0019] It should be noted that the hypophosphite may be anhydrous hypophosphite and / or hypophosphite hydrate.

[0020] Preferably, the hypophosphite is sodium hypophosphite, and the solution obtained in step (1) is a sodium diethylphosphinate aqueous solution.

[0021] Preferably, the mass percentage of hypophosphite in the hypophosphite aqueous solution is 10-60%, for example, it can be 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50% or 55%, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range, and 30-40% is further preferred.

[0022] Preferably, the antioxidant comprises any one of hindered amine antioxidants, hindered phenol antioxidants, phosphite antioxidants, and thioester antioxidants, or a combination of at least two thereof, and more preferably any one of hindered phenol antioxidants, phosphite antioxidants, and thioester antioxidants, or a combination of at least two thereof.

[0023] Further preferably, the antioxidant includes pentaerythritol tetrakis(β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (antioxidant 1010), β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (antioxidant 1076), N,N'-bis-(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)hexanediamine (antioxidant 1098), tris(2,4-di-tert-butylphenyl)phosphite (antioxidant 168), 2,6-di-tert-butyl-p-cresol (antioxidant BHT), β,β-distearate thiodipropionate (antioxidant DSTP), antioxidant 215, and antioxidant 225, or a combination of at least two of them.

[0024] The antioxidant in the present invention can be a single component, such as any one of the antioxidants listed above, or a combination of multiple compound antioxidants, such as a combination of a hindered phenol antioxidant and a phosphite antioxidant. A typical combination is a compound of antioxidant 1010 and antioxidant 168 in different proportions, such as antioxidant 215, antioxidant 225, etc.

[0025] Preferably, the mass ratio of the hypophosphite to the antioxidant is 100:(0.02-1.2), for example, it can be 100:0.04, 100:0.05, 100:0.06, 100:0.08, 100:0.1, 100:0.2, 100:0.3, 100:0.4, 100:0.5, 100:0.6, 100:0.7, 100:0.8, 100:0.9, 100:0.95, 100:1, 100:1.05, 100:1.1 or 100:1.15, and more preferably 100:(0.05-1).

[0026] Preferably, the initiator includes any one of an organic peroxide, a persulfate, an azo initiator, and a photoinitiator, or a combination of at least two of them.

[0027] Preferably, the organic peroxide comprises diisobutyryl peroxide, benzoyl peroxide, bis(2-ethylhexyl) peroxydicarbonate, diisopropyl peroxydicarbonate, 1,1,3,3-tetramethylbutyl peroxypivalate, tert-butyl peroxypivalate, t-pentyl peroxypivalate, dilauroyl peroxide, di(3,3,5-trimethylacetyl) peroxide, 2,5-dimethyl-2,5-di(2-ethylacetyl peroxide)hexane, 1,1,3,3-tetramethylbutyl peroxy-2-ethylhexanoate, di(4-methylbenzoyl) peroxide, 2-(2-ethylhexanoate) peroxide, di(4-methylbenzoyl) peroxide, di(2 ... Any one of tert-butyl peroxy-2-ethylhexanoate, tert-butyl peroxyisobutyrate, 1,1-di-tert-butyl peroxy-3,3,5-trimethylcyclohexane, 1,1-di-tert-pentyl peroxycyclohexane, 1,1-di-tert-butyl peroxycyclohexane, di-tert-butyl peroxide, di-tert-pentyl peroxide, diisopropylbenzene peroxide, 2,5-di-tert-butyl peroxide-2,5-dimethylhexane, tert-butyl peroxyacetate, tert-butyl peroxybenzoate, tert-butyl peroxymaleate, and tert-butyl peroxy-2-ethylhexyl carbonate, or a combination of at least two thereof.

[0028] Preferably, the persulfate includes any one of sodium persulfate, potassium persulfate, and ammonium persulfate, or a combination of at least two of them.

[0029] Preferably, the azo initiator includes any one of azobisisobutyronitrile, azobisisoheptanenitrile, azobisisobutyramidine hydrochloride, azobisisobutylimidazoline hydrochloride, and azoisobutylcyanoformamide, or a combination of at least two thereof.

[0030] It should be noted that the present invention does not have any special restrictions on the specific selection of the photoinitiator, and all commonly used photoinitiators in the art are applicable.

[0031] It should be noted that the initiator in step (1) of the present invention can be added all at once, in batches, or continuously during the reaction process; and a portion of the initiator in step (1) can be added in advance, and the rest can be added continuously during the reaction process.

[0032] Preferably, the mass ratio of the hypophosphite to the initiator is 100:(0.1-5), for example, it can be 100:0.2, 100:0.5, 100:1, 100:1.5, 100:2, 100:2.5, 100:3, 100:3.5, 100:4, 100:4.5 or 100:4.8, etc.

[0033] Preferably, the molar ratio of ethylene to hypophosphite is (2-2.1):1, for example, it can be 2.01:1, 2.02:1, 2.04:1, 2.05:1, 2.06:1, 2.08:1 or 2.09:1, etc.

[0034] Preferably, the temperature of the free radical reaction is 70-120°C, for example, it can be 75°C, 80°C, 85°C, 90°C, 95°C, 100°C, 105°C, 110°C or 115°C, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range, more preferably 80-110°C, and further preferably 90-105°C.

[0035] The free radical reaction in step (1) is carried out in the presence of an initiator. When the pressure of the reaction system substantially no longer changes, the reaction is considered complete and the reaction is stopped.

[0036] Preferably, the free radical reaction is carried out in a protective atmosphere.

[0037] Preferably, the protective atmosphere includes a nitrogen atmosphere and / or an argon atmosphere.

[0038] In the present invention, the metal salt in step (2) is a water-soluble metal salt. Preferably, the metal salt comprises metal sulfate and / or metal chloride, more preferably metal sulfate.

[0039] Preferably, the metal in the metal salt includes any one of Al, Ca, Cu, Zn, Fe, and Ti, or a combination of at least two thereof, and Al is more preferred.

[0040] Preferably, the metal salt comprises aluminum sulfate.

[0041] It should be noted that the metal salt may be an anhydrous metal salt and / or a metal salt hydrate.

[0042] Preferably, the mass percentage of the metal salt in the metal salt aqueous solution is 20-40%, for example, it can be 22%, 25%, 28%, 30%, 32%, 35% or 38%, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0043] Preferably, the molar ratio of the metal salt to diethylphosphinate is 1:(5.8-6.2), for example, it can be 1:5.82, 1:5.85, 1:5.88, 1:5.9, 1:5.92, 1:5.95, 1:5.98, 1:6, 1:6.02, 1:6.05, 1:6.08, 1:6.1, 1:6.12, 1:6.15 or 1:6.18, etc., and 1:6 is more preferred.

[0044] Preferably, the alkali solution comprises sodium hydroxide solution and / or potassium hydroxide solution.

[0045] The present invention does not have any special restrictions on the mass concentration of the sodium hydroxide solution and the potassium hydroxide solution. It only needs to add the sodium hydroxide solution and / or the potassium hydroxide solution to maintain the pH of the reaction system obtained in step (2) at 3.5-3.8.

[0046] Preferably, the reaction temperature in step (2) is 20-80°C, for example, it can be 25°C, 30°C, 35°C, 40°C, 45°C, 50°C, 55°C, 60°C, 65°C, 70°C or 75°C, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range, and it is further preferably 40-60°C.

[0047] Preferably, the reaction time of step (2) is 0.1-5h, for example, it can be 0.2h, 0.5h, 0.8h, 1h, 1.2h, 1.5h, 1.8h, 2h, 2.2h, 2.5h, 2.8h, 3h, 3.2h, 3.5h, 3.8h, 4h or 4.5h, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the said range.

[0048] It should be noted that in step (2) of the present invention, the metal salt aqueous solution and the alkali solution are simultaneously added to the diethylphosphinate aqueous solution for reaction, or the metal salt aqueous solution, the alkali solution and the diethylphosphinate aqueous solution are continuously added to a reaction device (such as a stirred reactor, a static mixer, a dynamic mixer) at a constant flow rate for sufficient mixing reaction. Wherein, when the metal salt aqueous solution and the alkali solution are simultaneously added to the diethylphosphinate aqueous solution for reaction, the reaction temperature is 20-80°C, preferably 30-70°C, and more preferably 40-60°C, and the dropwise addition time of the metal salt aqueous solution and the alkali solution is 0.1-5h (for example, 0.5h, 1h, 1.5h, 2h, 2.5h, 3h, 3.5h, 4h, 4.5h, etc.), preferably 0.5-3h, and more preferably 1h-3h; when the metal salt aqueous solution, the alkali solution and the diethylphosphinate aqueous solution are continuously added to the reaction container at a constant flow rate, the reaction temperature is 40-80°C, preferably 50-60°C, and the reaction space velocity is 0.1-2 / h (for example, 0.2 / h, 0.5 / h, 0.8 / h, 1 / h, 1.2 / h, 1.5 / h, 1.8 / h, etc.), preferably 0.3-1 / h, and more preferably 0.5-0.8 / h.

[0049] Preferably, the flocculant includes any one of polyacrylamide flocculants, starch flocculants, and chitosan flocculants, or a combination of at least two of them.

[0050] Further preferably, the flocculant comprises anionic polyacrylamide and / or nonionic polyacrylamide.

[0051] As a preferred technical solution of the present invention, the use of polyacrylamide flocculants (preferably anionic polyacrylamide and / or nonionic polyacrylamide) can fix the surface of the polymer additive particles on the molecular chain of the flocculant to form a polymer bridge. In particular, when anionic polyacrylamide is added as a flocculant, adsorption bridging and enhancement effects can be produced, so that the particles form a group and settle, thereby improving the filtering and washing effect of the polymer additive and reducing the acid value of the polymer additive after filtering and washing.

[0052] Preferably, based on the theoretical mass of the metal diethylphosphinate as 100%, the mass of the flocculant is 0.01-0.5%, for example, it can be 0.02%, 0.05%, 0.08%, 0.1%, 0.12%, 0.15%, 0.18%, 0.2%, 0.22%, 0.25%, 0.28%, 0.3%, 0.32%, 0.35%, 0.38%, 0.4%, 0.42%, 0.45% or 0.48%, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0053] The “theoretical mass of diethylphosphinate metal salt” is calculated based on the input amounts of diethylphosphinate and metal salt in step (2).

[0054] Preferably, the flocculant and water are first mixed at 20-30° C. for 10-20 minutes to obtain a flocculant solution, and then the flocculant solution is mixed with the diethylphosphinate metal salt slurry and stirred. The mass ratio of the flocculant to water is 1:(10-1000), for example, 1:50, 1:100, 1:200, 1:300, 1:400, 1:500, 1:600, 1:700, 1:800, 1:900 or 1:950, etc.

[0055] Preferably, the mixing temperature in step (3) is 40-60°C, for example, it can be 42°C, 44°C, 46°C, 48°C, 50°C, 52°C, 54°C, 56°C or 58°C, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0056] Preferably, the number of washings in step (3) is ≥ 4 times, for example, 5 times, 6 times, 7 times, 8 times, 9 times, 10 times or 12 times, etc., more preferably 5-10 times.

[0057] Preferably, the washing agent used in the washing is water.

[0058] As a preferred technical solution of the present invention, the diethyl hypophosphite metal salt flocculent is filtered and then washed multiple times, the number of washings being ≥4 times, preferably 5-10 times, so as to better remove impurities and acidic substances in the product and obtain the polymer additive with low acid value and better thermal stability.

[0059] Preferably, the mass ratio of water to solids in each washing is independently (1-10):1, for example, it can be 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1, etc., and more preferably (1.5-6):1; the solids are the solid products obtained by filtration.

[0060] Preferably, the drying temperature in step (3) is 105-250°C, for example, it can be 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 180°C, 200°C, 220°C or 240°C, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range, and 110-150°C is further preferred.

[0061] As a preferred technical solution of the present invention, the preparation method of the polymer additive specifically comprises the following steps:

[0062] (1) in a protective gas atmosphere, subjecting a hypophosphite aqueous solution and an antioxidant to a free radical reaction with ethylene in the presence of an initiator to obtain a diethylphosphinate aqueous solution;

[0063] The mass percentage of hypophosphite in the hypophosphite aqueous solution is 10-60%, and the mass ratio of hypophosphite, antioxidant and initiator is 100:(0.02-1.2):(0.1-5); the temperature of the free radical reaction is 70-120° C., and the reaction is terminated when the pressure of the system no longer changes;

[0064] (2) mixing the diethylphosphinate aqueous solution, the metal salt aqueous solution and the alkali solution, and reacting them at a pH of 3.5-3.8 and a temperature of 40-60° C. to obtain a diethylphosphinate metal salt slurry;

[0065] Wherein, the molar ratio of the metal salt to diethylphosphinate is 1:(5.9-6.1), and the mass percentage of the metal salt in the metal salt aqueous solution is 20-40%;

[0066] (3) mixing the diethylphosphinate metal salt slurry and the flocculant solution at 40-60° C. and stirring to obtain diethylphosphinate metal salt flocs; filtering the diethylphosphinate metal salt flocs, washing ≥4 times, and drying to obtain the polymer additive;

[0067] Wherein, based on the theoretical mass of the diethylphosphinate metal salt being 100%, the mass of the flocculant is 0.01-0.5%.

[0068] In a second aspect, the present invention provides a polymer additive, which is prepared by the preparation method described in the first aspect, and the water-soluble acid value of the polymer additive is ≤0.33 mg KOH / g; the polymer additive comprises the following components in parts by mass:

[0069]

[0070] The polymer additive provided by the present invention has a low acid value and excellent thermal stability, and its water-soluble acid value is ≤0.33 mg KOH / g. When it is used as a flame retardant in a polymer composition, it can inhibit the high-temperature decomposition of dialkylphosphinic acid, so that the polymer composition has a lower content of water-boiling precipitates, effectively improves its use stability under hot and humid conditions, prolongs its service life, and generates less mold deposit during the injection molding process.

[0071] The mass fraction of diethylphosphinate in the polymer additive is 96-99.88 parts, for example, it can be 96 parts, 96.2 parts, 96.5 parts, 96.8 parts, 96.9 parts, 97 parts, 97.2 parts, 97.5 parts, 97.8 parts, 98 parts, 98.2 parts, 98.5 parts, 98.8 parts, 99 parts, 99.2 parts, 99.5 parts, 99.6 parts or 99.8 parts, as well as specific points between the above points. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific points included in the range.

[0072] Preferably, the mass percentage of diethylphosphinate in the polymer additive is ≥95%, for example, it can be 95.5%, 96%, 96.2%, 96.5%, 96.8%, 97%, 97.2%, 97.5%, 97.8%, 98%, 98.2%, 98.5%, 98.8%, 99%, 99.2%, 99.5%, 99.8% or 99.88%, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0073] The mass fraction of ethyl butyl phosphinate in the polymer additive is 0.1-2 parts, for example, it can be 0.12 parts, 0.15 parts, 0.2 parts, 0.25 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.8 parts, 1 parts, 1.2 parts, 1.5 parts or 1.8 parts, as well as specific points between the above points. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific points included in the range.

[0074] The mass fraction of ethyl phosphonate in the polymer additive is 0.01-1 part, for example, it can be 0.02 part, 0.05 part, 0.1 part, 0.15 part, 0.2 part, 0.25 part, 0.3 part, 0.35 part, 0.4 part, 0.45 part, 0.5 part, 0.55 part, 0.6 part, 0.65 part, 0.7 part, 0.75 part, 0.8 part, 0.85 part, 0.9 part or 0.95 part, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0075] The mass fraction of monoethylphosphinate in the polymer additive is 0.01-1 part, for example, it can be 0.02 part, 0.05 part, 0.1 part, 0.15 part, 0.2 part, 0.25 part, 0.3 part, 0.35 part, 0.4 part, 0.45 part, 0.5 part, 0.55 part, 0.6 part, 0.65 part, 0.7 part, 0.75 part, 0.8 part, 0.85 part, 0.9 part or 0.95 part, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0076] Exemplarily, the mass fractions of diethylphosphinate, diethylphosphinate, ethylphosphonate, and monoethylphosphinate in the polymer additive can be obtained by liquid chromatography analysis and testing, for example, the sample to be tested is dissolved in a sulfuric acid aqueous solution (mass concentration 30%) with a mass ratio of 5 times that of the sample, and then diluted 10-30 times with a mobile phase for analysis and testing; the mobile phase is a mixture of water and methanol in a mass ratio of 9:1, trifluoroacetic acid with a volume content of 0.5%, a ShimNex CSC18 chromatographic column is used, and the flow rate is 0.6 mL / min; the mass content of each component is calculated by the area normalization method.

[0077] Preferably, the mass fraction of other phosphorus-containing compounds in the polymer additive is ≤1.2 parts, for example, it can be 0, 0.01 parts, 0.05 parts, 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, 1 parts or 1.1 parts, as well as specific values ​​between the above points. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively enumerates the specific points included in the range, and 0.05-0.9 parts is further preferred.

[0078] It should be noted that the other phosphorus-containing compounds are alkali-soluble and phosphorus-containing substances different from diethyl phosphinate, ethyl butyl phosphinate, ethyl phosphonate, and monoethyl phosphinate, and their mass fractions can be measured by nuclear magnetic phosphorus spectrum. In the nuclear magnetic phosphorus spectrum, the integrated area of ​​other peaks except diethyl phosphinate, ethyl butyl phosphinate, ethyl phosphonate, and monoethyl phosphinate represents the content of the other phosphorus-containing compounds.

[0079] Preferably, the polymer additive comprises the following components in parts by mass:

[0080]

[0081] Preferably, the cations in the diethylphosphinate, ethylbutylphosphinate, ethylphosphonate and monoethylphosphinate are the same and are selected from Al 3+ , Ca 2+ , Cu 2+ 、Zn 2+ , Fe 2+ , Fe 3+ or Ti 4+ Any one or a combination of at least two of the following.

[0082] In the present invention, the water-soluble acid value of the polymer additive is ≤0.33 mg KOH / g, for example, it can be 0.01 mg KOH / g, 0.1 mg KOH / g, 0.12 mg KOH / g, 0.15 mg KOH / g, 0.18 mg KOH / g, 0.2 mg KOH / g, 0.22 mg KOH / g, 0.25 mg KOH / g, 0.28 mg KOH / g, 0.29 mg KOH / g, 0.3 mg KOH / g, 0.31 mg KOH / g or 0.32 mg KOH / g, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively enumerates the specific point values ​​included in the range, preferably 0.1-0.3 mg KOH / g.

[0083] For example, the water-soluble acid value of the polymer additive can be obtained by testing as follows: 1 g of the sample to be tested is diluted with ethanol (the mass of ethanol is m 乙醇 ) after uniform wetting, add water (the mass of water is m 水 ), boiled in a sealed water container at 90℃ for 1h, cooled to 25℃ and kept at constant temperature for 30min, and added water to the total mass before boiling; filtered, and the mass of the clear filtrate was m 1 The test acid value of the clear filtrate is measured by potentiometric titration, wherein the concentration of the potassium hydroxide solution used for titration is 0.05 mol / L, and the water-soluble acid value of the polymer additive = test acid value × (m 水 +m 乙醇 ) / m 1 .

[0084] Preferably, the organic acid value of the polymer additive is ≤0.05 mg KOH / g, for example, it may be 0.001 mg KOH / g, 0.005 mg KOH / g, 0.01 mg KOH / g, 0.02 mg KOH / g, 0.022 mg KOH / g, 0.025 mg KOH / g, 0.028 mg KOH / g, 0.03 mg KOH / g, 0.032 mg KOH / g, 0.035 mg KOH / g, 0.038 mg KOH / g, 0.04 mg KOH / g or 0.045 mg KOH / g, as well as specific values ​​between the above points. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively enumerates the specific points included in the range, and 0.002-0.04 mg KOH / g is further preferred.

[0085] For example, the organic acid value of the polymer additive can be obtained by testing as follows: 1 g of the sample to be tested is diluted with dichloromethane (the mass of dichloromethane is m 二氯甲烷 ) after being uniformly moistened, boiled in a sealed container at 90°C for 1 hour, cooled to 25°C and kept at a constant temperature for 30 minutes, and dichloromethane was added to the total mass before boiling; filtered, and the mass of the clear filtrate was m 1 The test acid value of the clear filtrate is measured by potentiometric titration, wherein the concentration of the potassium hydroxide solution used for titration is 0.05 mol / L, and the organic acid value of the polymer additive = test acid value × m 二氯甲烷 / m 1 .

[0086] Preferably, the mass content of sulfate in the polymer additive is 100-600ppm, for example, it can be 120ppm, 150ppm, 200ppm, 250ppm, 270ppm, 300ppm, 350ppm, 400ppm, 420ppm, 450ppm, 500ppm, 550ppm or 580ppm, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively enumerates the specific point values ​​included in the range, and 110-370ppm is further preferred.

[0087] For example, the mass content of sulfate in the polymer additive is determined by an external standard method using ion chromatography technology with reference to the method in standard EN 14582:2007-Determination of halogen content.

[0088] Preferably, the 1% thermal weight loss temperature of the polymer additive is ≥350°C, for example, it can be 355°C, 358°C, 360°C, 362°C, 365°C, 368°C, 370°C, 372°C, 375°C, 378°C, 382°C or 385°C, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range, and 358-380°C is further preferred.

[0089] In the present invention, the term "1% thermal weight loss temperature" refers to the temperature corresponding to when the polymer additive loses 1% of its weight under heating conditions, which can be measured by a thermogravimetric analyzer (TGA) in an air atmosphere.

[0090] Preferably, the polymer additive has a D 50 The particle size is 1-100 μm, for example, it can be 10 μm, 20 μm, 30 μm, 33 μm, 35 μm, 38 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm or 95 μm, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range. It is further preferred to be 20-60 μm, and further preferred to be 33-39 μm.

[0091] The D of the polymer additive 50 The particle size refers to the particle size corresponding to 50% of the cumulative volume distribution percentage, which can be measured by a laser particle size analyzer with reference to the standard GB / T 19077-2016 particle size distribution laser diffraction method.

[0092] Preferably, the water content of the polymer additive is 0.01-1wt%, for example, it can be 0.02wt%, 0.05wt%, 0.08wt%, 0.1wt%, 0.15wt%, 0.2wt%, 0.25wt%, 0.3wt%, 0.4wt%, 0.5wt%, 0.6wt%, 0.7wt%, 0.8wt% or 0.9wt%, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range, and 0.05-0.3wt% is further preferred, and 0.1-0.25wt% is further preferred.

[0093] For example, the water content of the polymer additive can be obtained by testing with an infrared moisture analyzer, for example, using the MA35 infrared moisture analyzer produced by Sartorius of Germany, and automatically testing the water content of the sample after it is placed at 120° C. for 30 minutes.

[0094] Preferably, the phosphorus content of the polymer additive is 22-25wt%, for example, it can be 22.2wt%, 22.5wt%, 22.8wt%, 23wt%, 23.2wt%, 23.5wt%, 23.8wt%, 24wt%, 24.2wt%, 24.5wt% or 24.8wt%, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range, and 23-24wt% is further preferred.

[0095] For example, the phosphorus content of the polymer additive can be tested by the following method: dissolving the sample to be tested in a sulfuric acid aqueous solution (mass concentration 30%), and testing with reference to standard GB / T 11893-1989 "Determination of total phosphorus in water - ammonium molybdate spectrophotometry".

[0096] In a third aspect, the present invention provides a use of the polymer additive as described in the second aspect in a polymer material.

[0097] Preferably, the polymer additive is applied to the polymer material as a flame retardant.

[0098] Preferably, the polymer material comprises any one of polyamide, polyester, polyurethane, styrene-based polymer, polyolefin, polyphenylene ether, polyacrylate or a combination of at least two thereof, more preferably polyamide and / or polyester.

[0099] In a fourth aspect, the present invention provides a polymer composition comprising a polymer matrix and the polymer additive as described in the second aspect.

[0100] Preferably, the polymer composition comprises the following components in parts by mass:

[0101] Polymer matrix 40-99 parts

[0102] The polymer additive is 5-35 parts.

[0103] Preferably, the mass parts of the polymer matrix are 40-99 parts, for example, they can be 45 parts, 50 parts, 55 parts, 60 parts, 65 parts, 70 parts, 75 parts, 80 parts, 85 parts, 90 parts, 95 parts or 98 parts, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0104] Preferably, the mass parts of the polymer additive are 5-35 parts, for example, they can be 6 parts, 8 parts, 10 parts, 12 parts, 15 parts, 18 parts, 20 parts, 22 parts, 25 parts, 28 parts, 30 parts, 32 parts or 34 parts, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0105] Preferably, the polymer matrix comprises polyamide and / or polyester.

[0106] Preferably, the polyamide includes any one of polyamide resin and polyamide elastomer, or a combination of at least two of them.

[0107] As a polyamide, it includes any one or a combination of at least two of the condensation products of dicarboxylic acids and diamines, condensation products of ω-amino acids, and ring-opening polymerization products of cyclic lactams. The dicarboxylic acids exemplarily include but are not limited to: any one or a combination of at least two of adipic acid, sebacic acid, dodecanedioic acid, terephthalic acid, and isophthalic acid. The diamines exemplarily include but are not limited to: any one or a combination of at least two of pentamethylenediamine, hexamethylenediamine, decanediamine, dodecanediamine, butanediamine, p-phenylenediamine, and m-phenylenediamine. The cyclic lactams exemplarily include but are not limited to: any one or a combination of at least two of caprolactam, capryllactam, undecane lactam, and lauryl lactam. The ω-amino acids exemplarily include but are not limited to: any one or a combination of at least two of the ω-amino acids and aminobenzoic acids formed by the ring opening of the aforementioned cyclic lactams.

[0108] Preferably, the polyamide includes any one of polyamide 6 (polycaprolactam), polyamide 11 (polyundecalactam), polyamide 12 (polydodecalactam), polyamide 56 (polypentamethylene adipamide), polyamide 66 (polyhexamethylene adipamide), polyamide 610 (polyhexamethylene sebacate), polyamide 612 (polyhexamethylene dodecanediamide), polyamide 1010 (polydecanediamide), polyamide 1012 (polydecanediamide), polyamide 1212 (polydodecanediamide), polyamide 6T (polyhexamethylene terephthalamide), polyamide 10T (polydecanediamide), and PPA (polyparaphenylene terephthalamide), or a combination of at least two thereof.

[0109] Preferably, the polyester comprises a condensation product of a dicarboxylic acid and / or its derivatives with a diol, wherein the dicarboxylic acid exemplarily includes but is not limited to: any one or a combination of at least two of terephthalic acid, isophthalic acid, phthalic acid, succinic acid, adipic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, cyclohexanedicarboxylic acid, hydrogenated isophthalic acid, hydrogenated phthalic acid, and the derivatives include acyl halides (chlorides), esters, anhydrides, etc. formed from dicarboxylic acids. The diol exemplarily includes but is not limited to: any one or a combination of at least two of ethylene glycol, butanediol, and hexanediol.

[0110] Exemplarily, the polyester includes polyethylene terephthalate (PET) and / or polybutylene terephthalate (PBT).

[0111] It should be noted that the polymer composition of the present invention may also include any other fillers, other additives, etc. that are added with motivation in the art.

[0112] Preferably, the polymer composition further comprises reinforcing materials and / or fillers.

[0113] Preferably, the reinforcing material comprises glass fiber and / or carbon fiber.

[0114] Preferably, the mass fraction of the reinforcing material in the polymer composition is ≤45 parts, and the mass fraction of the reinforcing material can be 0, 0.5, 1, 2, 5, 8, 10, 15, 20, 25, 30, 35, 40, 42 or 44 parts, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0115] Preferably, the filler includes any one of silicon dioxide, talc, titanium dioxide, barium sulfate, kaolin, calcium sulfate, boehmite, mica, magnesium carbonate, and glass microspheres, or a combination of at least two thereof.

[0116] Preferably, the mass fraction of filler in the polymer composition is ≤40 parts, and the mass fraction of filler can be 0, 0.5, 1, 2, 5, 8, 10, 12, 15, 18, 20, 22, 25, 28, 30, 32, 35 or 38 parts, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0117] Preferably, the polymer composition further includes 0-15 parts by mass of other additives, and the mass parts of the other additives can be 0, 0.1, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12 or 14 parts, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0118] Preferably, the other additives include any one of an antioxidant, an ultraviolet absorber, a lubricant, a nucleating agent, a stabilizer, an antistatic agent, and a colorant, or a combination of at least two of them.

[0119] Preferably, the polymer composition further comprises any one of an antioxidant, an ultraviolet absorber, a lubricant, a nucleating agent, a stabilizer, an antistatic agent, and a colorant, or a combination of at least two thereof.

[0120] Preferably, the weight parts of antioxidant, ultraviolet absorber, lubricant and nucleating agent in the polymer composition are each independently 0.01-1.5 parts, for example, 0.05 parts, 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, 1 parts, 1.2 parts or 1.4 parts, as well as specific points between the above points. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific points included in the range.

[0121] Preferably, the antioxidant in the polymer composition includes any one of a hindered amine antioxidant, a hindered phenol antioxidant, a phosphite antioxidant, and a thioester antioxidant, or a combination of at least two thereof.

[0122] Exemplarily, the antioxidant in the polymer composition includes pentaerythritol tetrakis(β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (antioxidant 1010), β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (antioxidant 1076), N,N'-bis-(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)hexanediamine (antioxidant 1098), tris(2,4-di-tert-butylphenyl)phosphite (antioxidant 168), bis(2,4-dicumylphenyl)pentaerythritol diphosphite (antioxidant 608), 2,6-di-tert-butyl-p-cresol (antioxidant BHT), distearyl β,β-thiodipropionate (antioxidant DSTP), antioxidant 215, and antioxidant 225, or any one or a combination of at least two thereof.

[0123] Preferably, the lubricant includes any one of ester lubricants, alcohol lubricants, hydrocarbon lubricants, fatty acid lubricants, fatty acid amide lubricants, and metal soap lubricants, or a combination of at least two of them.

[0124] Preferably, the polymer composition further includes 0-15 parts by mass of a synergistic flame retardant, and the mass percentage of the synergistic flame retardant can be 0, 0.1, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12 or 14 parts, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0125] Preferably, the synergistic flame retardant includes any one of melamine polyphosphate, melamine polyphosphate salt, zinc borate, zinc stannate, zinc sulfide, and boehmite, or a combination of at least two thereof.

[0126] In a preferred technical solution, the polymer composition comprises the following components in parts by mass:

[0127]

[0128] Preferably, the mass percentage of the polymer matrix in the polymer composition is 40%-99%, for example, it can be 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95% or 98%, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0129] Preferably, the mass percentage of the polymer additive in the polymer composition is 5%-35%, for example, it can be 6%, 8%, 10%, 12%, 15%, 18%, 20%, 22%, 25%, 28%, 30%, 32% or 34%, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range, and 6%-20% is further preferred.

[0130] Illustratively, the method for preparing the polymer composition comprises: melt-blending the components of the polymer composition and then extruding to obtain the polymer composition.

[0131] Preferably, the melt blending is carried out in a screw extruder.

[0132] Preferably, the screw extruder is a twin-screw extruder.

[0133] Preferably, the temperature of the screw extruder is 180-330°C, for example, it can be 190°C, 200°C, 210°C, 220°C, 230°C, 240°C, 250°C, 260°C, 270°C, 280°C, 290°C, 300°C, 310°C or 320°C, as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0134] Preferably, the extrusion further includes granulation and drying steps.

[0135] Compared with the prior art, the present invention has the following beneficial effects:

[0136] In the preparation method of the polymer additive provided by the present invention, a polymer additive with low acid value and high thermal stability can be obtained by designing materials such as antioxidants and flocculants, designing process steps and parameters, and their combined effect. When the polymer additive is used as a flame retardant to prepare a polymer composition, it can significantly reduce mold scale generated by injection molding, and make the polymer composition have a lower content of boiled precipitates, greatly improving the stability of the polymer composition under hot and humid conditions and extending its service life. DETAILED DESCRIPTION

[0137] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0138] As used herein, the terms "comprises," "including," "having," "containing," or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises the listed elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus.

[0139] In the following specific implementation manner, the test method of the parameters of the polymer additive is as follows:

[0140] (1) Content test of diethylphosphinate, ethylbutylphosphinate, ethylphosphonate and monoethylphosphinate

[0141] The results were obtained by analysis and testing using a liquid chromatograph (LC20A, Shimadzu, Japan), wherein diethyl phosphinate used a commercially available standard sample, ethyl butyl phosphinate used its pure product (prepared with reference to Example 4 of CN103172668A) as a standard sample, ethyl phosphonate used its pure product (prepared with reference to Example 2 of CN104371142A) as a standard sample, and monoethyl phosphinate used its pure product (prepared with reference to Example 1 of CN103172668A) as a standard sample; the sample to be tested was dissolved in a sulfuric acid aqueous solution (mass concentration 30%) with a mass of 5 times that of the sample, and then diluted 20 times with a mobile phase for analysis and testing; the mobile phase used a mixed solution of water and methanol in a mass ratio of 9:1, and trifluoroacetic acid with a volume content of 0.5% was added, and the chromatographic column used ShimNex CS C18 5μm, 4.6×250mm, and the flow rate was 0.6mL / min; the mass content of each component was calculated by the area normalization method.

[0142] (2) Content of other phosphorus-containing compounds

[0143] The sample to be tested is mixed with a deuterated aqueous solution of deuterated sodium hydroxide (mass concentration 10%) in a mass ratio of 1:30 to completely dissolve the sample, filter it, and measure the nuclear magnetic phosphorus spectrum of the obtained clear liquid by a nuclear magnetic resonance instrument (NMR, Bruker nuclear magnetic resonance NMR spectrometer, AVANCENEO 400MHz). The nuclear magnetic phosphorus spectrum is integrated, and the integral area ratio of other peaks except the known diethyl phosphinate, ethyl butyl phosphinate, ethyl phosphonate, and monoethyl phosphinate is regarded as the content of the other phosphorus-containing compounds.

[0144] (3) Water-soluble acid value

[0145] Take 1g of the sample to be tested and add 5.00±0.01g(m 乙醇 ) ethanol evenly wetted, add 50±0.01g(m 水 ) Room temperature water, with bottle and stirring weighing total weight m 0 , boiled in sealed water at 90℃ for 1h, cooled to 25℃ and kept at constant temperature for 30min, and added water to a total weight of m 0 ; Filter, and the mass of the clear filtrate is m 1 The test acid value of the clear filtrate is measured by potentiometric titration, wherein the concentration of the potassium hydroxide solution used for titration is 0.05 mol / L, and the water-soluble acid value of the polymer additive = test acid value × (m 水 +m 乙醇 ) / m 1 .

[0146] (4) Organic acid value

[0147] Take 1g of the sample to be tested and add 50.0±0.01g (m 二氯甲烷) After being uniformly moistened in dichloromethane, weigh the total weight m with bottle and stirring 0 , boiled in a sealed container at 90℃ for 1h, cooled to 25℃ and kept at constant temperature for 30min, and then added with dichloromethane to a total weight of m 0 ; Filter, and the mass of the clear filtrate is m 1 The test acid value of the clear filtrate is measured by potentiometric titration, wherein the concentration of the potassium hydroxide solution used for titration is 0.05 mol / L, and the organic acid value of the polymer additive = test acid value × m 二氯甲烷 / m 1 .

[0148] (5) Sulfate content

[0149] Referring to the method in standard EN 14582:2007-Determination of halogen content, the measurement was carried out using ion chromatography technology and external standard method.

[0150] (6)D 50 Particle size

[0151] Take 0.1 g of the sample to be tested, moisten it with 5 g of ethanol, then add 50 mL of water to dilute it, and use Mastersizer 3000 laser particle size analyzer for testing.

[0152] (7) Moisture content

[0153] The sample to be tested was placed in an infrared moisture analyzer (MA35, Sartorius, Germany) and the water content was automatically tested after being placed at 105°C for 30 minutes.

[0154] (8) Phosphorus content

[0155] Take 0.1g of the sample to be tested, add 2g of sulfuric acid aqueous solution (mass concentration 30%) to dissolve, and test according to the reference standard GB / T 11893-1989 "Determination of total phosphorus in water quality - Ammonium molybdate spectrophotometry".

[0156] (9) 1% thermal weight loss temperature

[0157] 10 mg of the sample to be tested was taken and tested using a thermogravimetric analyzer (TGA, NETZSCH TG 209F3, Germany) with a heating rate of 20°C / min, nitrogen as the protective gas, air as the purge gas, and the temperature corresponding to 1% weight loss was tested.

[0158] In the following specific embodiments of the present invention, all materials for which no preparation method is provided are commercially available chemicals, and the specific information of some materials is as follows:

[0159] Brand, manufacturer Antioxidant 1010 RIANOX 1010, Tianjin Li'anlong New Materials Co., Ltd. Antioxidant 168 RIANOX 168, Tianjin Li'anlong New Materials Co., Ltd. Flocculant: Anionic polyacrylamide Gongyi Xinqi Polymer Co., Ltd. Polyamide 66 (PA66) PA66 M2000, Guangdong Xinhui Meida Nylon Co., Ltd. Polyamide 6 (PA6) PA6 EPR24, Shenma Industrial Co., Ltd. Melamine polyphosphate (MPP) BUDIT 3141, Budenheim, Germany Fiberglass ECS10-03-568H, China Jushi Co., Ltd. Lubricants TR044W, Struktol, Germany Antioxidant 1098 RIANOX 1098, Tianjin Li'anlong New Materials Co., Ltd.

[0160] The polymer additive and the preparation method thereof of the present invention will be described in detail below by taking a plurality of embodiments as examples, but the polymer additive and the preparation method thereof are not limited to these embodiments.

[0161] Examples 1-11, Comparative Examples 1-4

[0162] A polymer additive and a preparation method thereof, wherein the preparation method is as follows:

[0163] (1) 31.8 kg solid sodium hypophosphite monohydrate, 50 kg water, 500 g sodium persulfate, and a mass of m 1 The antioxidant 1010 and the mass m 2 The antioxidant 168 is put into an autoclave, and the nitrogen is replaced for 3 times. The ethylene pressure is kept constant to 1.5 MPa through a pressure reducer, and the autoclave is heated to 95°C and kept warm for 4 hours. 2500 g of a 20% sodium persulfate aqueous solution is continuously added during the 4-hour heat preservation process, and then kept warm at 95°C for 1 hour, cooled and vented to obtain a sodium diethylphosphinate aqueous solution.

[0164] (2) diluting the sodium diethylphosphinate aqueous solution obtained in step (1) to a mass content of 20% sodium diethylphosphinate (containing 6 mol of sodium diethylphosphinate), and heating to a temperature T 1 , continuously dripping an aluminum sulfate aqueous solution (1 mol of aluminum sulfate, 28% by mass) within 1 hour, and adjusting the pH value with a potassium hydroxide solution (5% by mass) to obtain a diethyl aluminum phosphinate slurry;

[0165] (3) adding a mass of m to the diethylphosphinate aluminum slurry obtained in step (2) at 50°C 3 A flocculant aqueous solution prepared by mixing 50 g of anionic polyacrylamide and 50 g of water was stirred to a flocculated state, filtered, and the filter cake was washed 5 times with 3 times the mass of water, and dried at 110° C. to a constant weight to obtain a polymer additive.

[0166] The specific process parameters of the preparation method and the relevant data of the prepared polymer additive are shown in Tables 1 and 2.

[0167] Table 1

[0168]

[0169]

[0170] Table 2

[0171]

[0172]

[0173] As can be seen from Table 1, the present invention designs a method for preparing a polymer additive, and in particular, through the use of an antioxidant and a flocculant and the control of the pH value in the double decomposition reaction system in step (2), a polymer additive with low acid value and high thermal stability is prepared, wherein the water-soluble acid value is ≤0.33 mg KOH / g, and the 1% thermal weight loss temperature is ≥350° C. The polymer additive comprises the following components in parts by mass: 96-99.88 parts of diethyl phosphinate, 0.1-2 parts of ethyl butyl phosphinate, 0.01-1 parts of ethyl phosphonate, and 0.01-1 parts of monoethyl phosphinate.

[0174] In Table 2, the pH value of the reaction system in step (2) of Comparative Examples 1-2 exceeds the range of 3.5-3.8 specified in the present invention, no antioxidant is used in Comparative Example 3, and no flocculant is added in Comparative Example 4, resulting in a significant increase in the water-soluble acid value and organic acid value of the polymer additive, a decrease in the 1% thermal weight loss temperature, and a decrease in thermal stability.

[0175] The application of the polymer additive of the present invention will be described in detail below using application examples, but the application of the polymer additive is not limited to these application examples.

[0176] Application Example 1-11, Comparative Application Example 1-4

[0177] A polymer composition, specifically a polyamide composition, the types and amounts of the components are shown in Table 3 and Table 4, and the units of the amounts of the components are all "parts by mass".

[0178] The preparation method of the polyamide composition comprises: mixing polyamide 66, polyamide 6, glass fiber, polymer additives, antioxidants and lubricants according to the formula amount to obtain a premix; adding the premix to a twin-screw extruder, wherein the screw speed of the twin-screw extruder is 380 rpm, the temperatures of zones 1-12 are 90° C., 180° C., 260° C., 250° C., 230° C., 230° C., 220° C., 220° C., 220° C., 220° C., 260° C., and 260° C. respectively, and obtaining polyamide composition particles through melt mixing and extrusion granulation.

[0179] The following performance tests were performed on the polyamide composition:

[0180] (1) Boiling phosphorus content test: Take 50 g of the polyamide composition particles, add them into 500 mL of 90° C. hot water, boil for 1 h, cool to room temperature, filter, and measure the phosphorus content of the filtrate using the ammonium molybdate spectrophotometric method in accordance with GB / T 11893-1989;

[0181] (2) Mold deposit test method: using an injection molding machine, the polyamide composition particles are continuously injected for 150 molds at injection temperatures of 290° C., 285° C., 280° C., and 260° C., and the mold deposit sample collected in the last mold is taken out and weighed using an analytical balance;

[0182] The test data are shown in Table 3 and Table 4.

[0183] Table 3

[0184]

[0185] Table 4

[0186]

[0187]

[0188] According to the data in Table 3 and Table 4, the polymer additive provided by the present invention is used as a flame retardant in a polyamide composition, which significantly reduces the mold deposit generated by injection molding, making the mold deposit ≤8.0 mg, and the water-boiled phosphorus content of the polyamide composition ≤527 ppm, thereby reducing the content of water-boiled precipitates, improving the stability of the polyamide composition under hot and humid conditions, and extending the service life.

[0189] According to the test data in Table 4, since the polymer additives of Comparative Examples 1-4 have high acid values ​​and poor thermal stability, when used as flame retardants in polyamide compositions, there is a lot of injection mold deposits, a high content of boiled phosphorus, and insufficient stability in use under hot and humid conditions.

[0190] The applicant declares that the present invention uses the above-mentioned embodiments to illustrate the polymer additive and the preparation method thereof, and the polymer composition containing the same, but the present invention is not limited to the above-mentioned embodiments, that is, it does not mean that the present invention must rely on the above-mentioned embodiments to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of various raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A method for preparing a polymer additive, characterized in that: The preparation method comprises the following steps: (1) a hypophosphite aqueous solution and an antioxidant react with ethylene in the presence of an initiator to obtain a diethylphosphinate aqueous solution; (2) mixing the diethylphosphinate aqueous solution, the metal salt aqueous solution and the alkali solution, and reacting them at a pH value of 3.5-3.8 to obtain a diethylphosphinate metal salt slurry; (3) mixing the diethylphosphinate metal salt slurry and a flocculant, stirring to obtain diethylphosphinate metal salt flocs; filtering, washing and drying the diethylphosphinate metal salt flocs to obtain the polymer additive.

2. The preparation method according to claim 1, characterized in that: The hypophosphite includes sodium hypophosphite and / or potassium hypophosphite; Preferably, the mass percentage of hypophosphite in the hypophosphite aqueous solution is 10-60%, more preferably 30-40%; Preferably, the antioxidant comprises any one of hindered amine antioxidants, hindered phenol antioxidants, phosphite antioxidants, and thioester antioxidants, or a combination of at least two thereof, and more preferably any one of hindered phenol antioxidants, phosphite antioxidants, and thioester antioxidants, or a combination of at least two thereof; Preferably, the antioxidant includes any one of pentaerythritol tetrakis(β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, n-octadecylβ-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, N,N'-bis-(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)hexanediamine, tris(2,4-di-tert-butylphenyl)phosphite, 2,6-di-tert-butyl-p-cresol, and distearylβ,β-thiodipropionate, or a combination of at least two thereof; Preferably, the mass ratio of the hypophosphite to the antioxidant is 100:(0.02-1.2), and more preferably 100:(0.05-1).

3. The preparation method according to claim 1, characterized in that: The initiator includes any one of organic peroxides, persulfates, azo initiators, and photoinitiators, or a combination of at least two thereof; Preferably, the mass ratio of the hypophosphite to the initiator is 100:(0.1-5).

4. The preparation method according to claim 1, characterized in that: The temperature of the free radical reaction is 70-120°C, preferably 80-110°C, and more preferably 90-105°C; Preferably, the free radical reaction is carried out in a protective atmosphere; Preferably, the protective atmosphere includes a nitrogen atmosphere and / or an argon atmosphere.

5. The preparation method according to claim 1, characterized in that: The metal salt comprises metal sulfate and / or metal chloride, preferably metal sulfate; Preferably, the metal in the metal salt includes any one or a combination of at least two of Al, Ca, Cu, Zn, Fe, and Ti, and Al is more preferred; Preferably, the alkali solution comprises sodium hydroxide solution and / or potassium hydroxide solution; Preferably, the reaction temperature in step (2) is 20-80°C, more preferably 40-60°C.

6. The preparation method according to claim 1, characterized in that: The flocculant includes anionic polyacrylamide and / or nonionic polyacrylamide; Preferably, based on the theoretical mass of the metal salt of diethylphosphinate as 100%, the mass of the flocculant is 0.01-0.5%; Preferably, the mixing temperature in step (3) is 40-60°C; Preferably, the number of washing steps in step (3) is ≥ 4 times.

7. A polymer additive, characterized in that The polymer additive is prepared by the preparation method according to any one of claims 1 to 6, and the water-soluble acid value of the polymer additive is ≤0.33 mg KOH / g; The polymer additive comprises the following components in parts by mass:

8. The polymer additive according to claim 7, characterized in that The water-soluble acid value of the polymer additive is 0.1-0.3 mg KOH / g; Preferably, the organic acid value of the polymer additive is ≤0.05 mg KOH / g, more preferably 0.002-0.04 mg KOH / g; Preferably, the mass content of sulfate in the polymer additive is 100-600 ppm, more preferably 110-370 ppm; Preferably, the 1% thermal weight loss temperature of the polymer additive is ≥350°C; Preferably, the polymer additive has a D 50 The particle size is 1-100 μm, more preferably 20-60 μm, and further preferably 33-39 μm; Preferably, the water content of the polymer additive is 0.01-1wt%, more preferably 0.05-0.3wt%, and even more preferably 0.1-0.25wt%; Preferably, the phosphorus content of the polymer additive is 22-25 wt %, more preferably 23-24 wt %.

9. Use of the polymer additive according to claim 7 or 8 in a polymer material; Preferably, the polymer additive is applied to the polymer material as a flame retardant.

10. A polymer composition, characterized in that The polymer composition comprises a polymer matrix and the polymer additive according to claim 7 or 8; Preferably, the polymer composition comprises the following components in parts by mass: 40-99 parts of polymer matrix, 5-35 parts of the polymer additive; Preferably, the polymer matrix comprises polyamide and / or polyester.

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