CN104927088A - Graphene/layered double hydroxide halogen-free flame retardant masterbatch and preparation method thereof - Google Patents

Abstract

The invention relates to a graphene/layered double hydroxide halogen-free flame-retardant masterbatch and a preparation method thereof. Prepared from the following components by weight: graphene/layered double hydroxide (LDH) composite: 20-90 parts; antioxidant: 0.5-2 parts; carrier: 10-80 parts; The graphene/layered double hydroxide (LDH) composite is prepared from graphene, LDH, organic solvent, and surfactant. The product of the present invention has the advantages of halogen-free flame retardancy, suitable for melt blending processing, less organic solvent, simple feeding, and good dispersibility. As a multi-scale composite masterbatch, it can be better dispersed in the polymer matrix and provide Polymers have better overall performance.

Description

Graphene/layered double hydroxide halogen-free flame-retardant masterbatch and preparation method thereof

technical field

The invention relates to a halogen-free flame-retardant masterbatch and a preparation method thereof, in particular to a graphene/layered double hydroxide halogen-free flame-retardant masterbatch and a preparation method thereof.

Background technique

Graphene is currently the thinnest but also the hardest nanomaterial in the world. It is almost completely transparent and only absorbs 2.3% of light; its thermal conductivity is as high as 5300 W/m·K. It has good application prospects in aerospace, new materials, new energy, electronics and other fields. In the practical application of graphene, polymer/graphene nanocomposites are considered to be one of the most promising directions. The main advantages of polymer/graphene composites lie in six aspects, namely, high thermal conductivity, high insulation, high flame retardancy, high mechanical strength, low density, low cost, and easy processing. These properties are revolutionary.

Layered double hydroxide LDH refers to a typical anionic type with the ideal composition of [N ²⁺ _{1 - x} M ³⁺ _x ·(OH) ₂ ] ^{x +} (A ^h- ) _{x / h} ·mH ₂ O Intercalation nanomaterials, where N ²⁺ is a divalent metal ion, including: Mg ²⁺ , Ca ²⁺ , Ba ²⁺ , Fe ²⁺ , Zn ²⁺ , Cu ²⁺ , Cr ²⁺ , Co ²⁺ , Ni ²⁺ ; M ³⁺ is a trivalent metal ion, including Al ³⁺ , Fe ³⁺ , Co ³⁺ , Ni ³⁺ . A is an anion, including NO ₃ ^- , Cl ^- , CO ₃ ^2- and SO ₄ ^2- , abbreviated as N _n M/A-LDH, and n is the molar ratio of N ²⁺ to M ³⁺ . As a nano-modifier, LDH has important applications in the field of polymer materials, and can be used as flame retardant and smoke suppressant, biological/medical materials, ultraviolet/infrared absorbing materials, etc. In recent years, polymer/LDH composites in particular have received extensive attention from researchers.

Polymer nanocomposites are prepared by dispersing nano-additives in the polymer matrix. However, due to the large specific surface of nano-fillers and the inherent van der Waals force, nano-materials are very easy to agglomerate. Therefore, nano-sized functional fillers are polymerized Uniform dispersion in the matrix is the key technology of polymer nanocomposites. At present, the methods for preparing polymer nanocomposites include solution composite method, in-situ polymerization method and melt blending method, among which the first two methods are easy to achieve uniform dispersion of nanomaterials in the polymer matrix, but use a large amount of organic solvents , leading to high cost and heavy pollution, which is not conducive to industrial production. However, if the composite material is prepared by the melt blending method, it is easy to cause uneven dispersion of nano-fillers, which will affect the final performance of the composite material.

Contents of the invention

One of the objectives of the present invention is to provide a graphene/layered double hydroxide halogen-free flame-retardant masterbatch and a preparation method thereof for the deficiencies of the prior art.

The object of the present invention is also to provide a preparation method of the graphene/LDH halogen-free flame-retardant masterbatch.

Above-mentioned purpose of the present invention is achieved by following technical scheme:

A graphene/layered double hydroxide halogen-free flame-retardant masterbatch, characterized in that the composition and parts by weight of the masterbatch are:

Graphene/ layered double hydroxide composite 20～90 parts

Antioxidant 0.5～2 parts

Carrier 10-80 copies;

The carrier is at least one of polycarbonate, polyethylene, polypropylene, acrylonitrile-butadiene-styrene and polyamide.

The specific preparation method of the above-mentioned graphene/layered double hydroxide (LDH) composite is:

a. Add LDH and organic solvent into the reactor according to the mass ratio of 0.05~0.5, ultrasonicate for 3~24 hours, then centrifuge at 1000~10000r/min for 10~120 minutes, filter the obtained mixture A, dry and set aside;

(2) Add graphene and organic solvent into the reactor according to the mass ratio of 0.05~0.5, ultrasonicate for 3~24 hours, then centrifuge at 1000~10000r/min for 10~120 minutes, filter the obtained mixture B, dry, and set aside ;

(3) Add the mixture A obtained in step (1), the mixture B obtained in step (2), and the surfactant into the reactor according to the mass ratio of 45~20:45~20:40~10, mix evenly, and ultrasonically for 0.5~3 hours, Then centrifuge at 1000~5000r/min for 10~60 minutes, dry and pulverize to obtain graphene/LDH composite.

The above-mentioned surfactant is one or both of silane coupling agents KH550, KH560, and KH570; the organic solvent is absolute ethanol or dimethylformamide (DMF).

The above-mentioned LDH refers to a class of typical anionic intercalation nanomaterials whose ideal composition is [N ²⁺ _{1 - x} M ³⁺ _x ·(OH) ₂ ] ^{x +} (A ^h- ) _{x / h} ·mH ₂ O, Among them, N ²⁺ is a divalent metal ion, including: Mg ²⁺ , Ca ²⁺ , Ba ²⁺ , Fe ²⁺ , Zn ²⁺ , Cu ²⁺ , Cr ²⁺ , Co ²⁺ , Ni ²⁺ ; M ^{3 +} is a trivalent metal ion, including Al ³⁺ , Fe ³⁺ ; A is an anion, including NO ₃ ^- , Cl ^- , CO ₃ ^2- , SO ₄ ^2- , abbreviated as N _n M/A-LDH.

The above-mentioned antioxidant is one or both of the antioxidant 1010 and the antioxidant 168.

A method for preparing the above-mentioned graphene/layered double hydroxide halogen-free flame-retardant masterbatch, characterized in that the specific steps of the method are: drying the graphene/layered double hydroxide composite at 100°C for 2h , adding the dried graphene/LDH compound together with the carrier and antioxidant into the high-speed mixer, stirring and mixing at high speed for 10-30 minutes, and pre-mixing to obtain the raw material mixture; adding the obtained raw material mixture into the extruder, Heat, melt and mix, granulate to obtain halogen-free flame retardant masterbatch.

The preparation method of the above-mentioned graphene/layered double hydroxide halogen-free flame retardant masterbatch is characterized in that the extruder is a twin-screw extruder, a reciprocating single-screw extruder or an internal mixer-single One of the screw extruders; the processing temperature of the extruder is 170~245°C.

Compared with the prior art, the outstanding effect of the present invention is: the masterbatch prepared by the present invention uses less organic solvent, reduces environmental pollution in the production process, and greatly reduces production cost, which is beneficial to industrial production. At the same time, the masterbatch adopts multi-scale composite technology and masterbatch technology, which can well solve the problems of difficult feeding, uneven dispersion and singleness of performance improvement in the process of composite material preparation. Finally, the mechanical properties and flame retardant properties of the composite material prepared by using the masterbatch are significantly improved, and are suitable for large-scale industrial production.

The preparation method provided by the invention has reasonable process, convenient operation, precise control, easy industrialization and low production cost.

Description of drawings

Figure 1 is the HRR data curve of the composite material prepared using the halogen-free flame retardant masterbatch prepared in Example 1.

Detailed ways

Example 1:

The graphene/layered double hydroxide halogen-free flame retardant masterbatch provided in this embodiment is prepared from the following components in parts by weight:

Graphene/LDH composite 90 parts

Antioxidant 1 part

Carrier 80 copies;

The preparation method of described graphene/LDH compound, concrete steps are as follows:

(1) Add LDH and organic solvent into the reactor at a mass ratio of 20:80, sonicate for 3 hours, then centrifuge at 10,000r/min for 60 minutes, filter the obtained mixture A, dry it, and set aside;

(2) Add graphene and organic solvent into the reactor at a mass ratio of 10:90, ultrasonicate for 3 hours, and then centrifuge at 10,000 r/min for 60 minutes, filter the obtained mixture B, dry it, and set aside;

(3) Add the mixture A obtained in step (1), the mixture B obtained in step (2), and the surfactant into the reactor according to the mass ratio of 30:30:40, mix evenly, ultrasonicate for 3 hours, and then centrifuge at 1000r/min for 60 minutes, dried, and ground to obtain graphene/LDH composites.

The surfactant is silane coupling agent KH550; the organic solvent is absolute ethanol. The LDH is Mg ₂ Al/CO ₃ -LDH.

The antioxidant is antioxidant 1010; the carrier is polycarbonate.

A method for preparing graphene/layered double hydroxide halogen-free flame-retardant masterbatch, which comprises the following steps:

(1) Accurately weigh the raw materials according to the following proportions:

Graphene/LDH composite 90 parts

Antioxidant 1 part

Carrier 80 copies;

(2) Dry the graphene/LDH composite at 100°C for 2 hours, add the dried graphene/LDH composite together with the carrier and antioxidant into the high-speed mixer, stir and mix at high speed for 10 minutes, and pre-mix to obtain the raw material mixture ;

(3) Add the mixture obtained in step (2) into a twin-screw extruder, melt extrude, and granulate to obtain a halogen-free flame-retardant masterbatch.

Example 2:

The graphene/layered double hydroxide halogen-free flame retardant masterbatch provided in this example is basically the same as Example 1, except that it is prepared from the following components by weight:

Graphene/LDH composite 60 parts

Antioxidant 0.5 parts

Carrier 70 copies;

The preparation method of described graphene/LDH compound, concrete steps are as follows:

(1) Add LDH and organic solvent into the reactor according to the mass ratio of 30:60, sonicate for 12 hours, then centrifuge at 10000r/min for 10 minutes, filter the obtained mixture A, dry it, and set aside;

(2) Add graphene and organic solvent into the reactor at a mass ratio of 20:80, sonicate for 12 hours, then centrifuge at 10,000 r/min for 30 minutes, filter the obtained mixture B, dry it, and set aside;

(3) Add the mixture A obtained in step (1), the mixture B obtained in step (2), and the surfactant into the reactor according to the mass ratio of 50:20:30, mix evenly, ultrasonicate for 0.5 hours, and then centrifuge at 1000r/min for 10 minutes, dried, and ground to obtain graphene/LDH composites.

The surfactant is silane coupling agent KH550; the organic solvent is absolute ethanol. The said LDH is Ni ₂ Al/CO ₃ -LDH.

The antioxidant is a mixture of antioxidant 1010 and antioxidant 168 with a mass ratio of 1:1; the carrier is polypropylene.

A method for preparing graphene/layered double hydroxide halogen-free flame-retardant masterbatch, which comprises the following steps:

(1) Accurately weigh the raw materials according to the following proportions:

Graphene/LDH composite 60 parts

Antioxidant 0.5 parts

Carrier 70 copies;

(2) Dry the graphene/LDH composite at 100°C for 2 hours, add the dried graphene/LDH composite together with the carrier and antioxidant into the high-speed mixer, stir and mix at high speed for 10 minutes, and pre-mix to obtain the raw material mixture ;

(3) Add the mixture obtained in step (2) into a twin-screw extruder, melt extrude, and granulate to obtain a halogen-free flame-retardant masterbatch.

Example 3:

The graphene/layered double hydroxide halogen-free flame retardant masterbatch provided in this example is basically the same as that of Examples 1 and 2, except that it is prepared from the following components in parts by weight:

Graphene/LDH composite 50 parts

Antioxidant 1 part

Carrier 50 copies;

The preparation method of described graphene/LDH compound, concrete steps are as follows:

(1) Add LDH and organic solvent into the reactor at a mass ratio of 10:90, sonicate for 6 hours, then centrifuge at 1000r/min for 20 minutes, filter the obtained mixture A, dry it, and set aside;

(2) Add graphene and organic solvent into the reactor at a mass ratio of 20:80, sonicate for 6 hours, then centrifuge at 1000r/min for 20 minutes, filter the obtained mixture B, dry it, and set aside;

(3) Add the mixture A obtained in step (1), the mixture B obtained in step (2), and the surfactant into the reactor according to the mass ratio of 30:30:40, mix evenly, ultrasonicate for 3 hours, and then centrifuge at 1000r/min for 10 minutes, dried, and ground to obtain graphene/LDH composites.

The surfactant is silane coupling agent KH570; the organic solvent is DMF. The layered double hydroxide (LDH) is Zn ₂ Al/NO ₃ -LDH.

The antioxidant is antioxidant 1010; the carrier is acrylonitrile-butadiene-styrene.

A method for preparing multi-scale composite graphene/layered double hydroxide halogen-free flame-retardant masterbatch, which comprises the following steps:

(1) Accurately weigh the raw materials according to the following proportions:

Graphene/LDH composite 50 parts

Antioxidant 1 part

Carrier 50 copies;

(2) Dry the graphene/LDH composite at 100°C for 2 hours, add the dried graphene/LDH composite together with the carrier and antioxidant into the high-speed mixer, stir and mix at high speed for 30 minutes, and pre-mix to obtain the raw material mixture ;

(3) Add the mixture obtained in step (2) into a twin-screw extruder, melt extrude, and granulate to obtain a halogen-free flame-retardant masterbatch.

The present invention is not limited to the above-mentioned embodiments, and other similar graphene/layered double hydroxide halogen-free flame-retardant masterbatches obtained by using the same or similar raw materials and preparation methods as the above-mentioned embodiments of the present invention and their preparation methods , are all within the protection scope of the present invention.

Claims (7)

1. A graphene/layered double hydroxide halogen-free flame-retardant master batch, characterized in that the composition and parts by weight of the master batch are: Graphene/ layered double hydroxide composite 20～90 parts Antioxidant 0.5～2 parts Carrier 10-80 copies; The carrier is at least one of polycarbonate, polyethylene, polypropylene, acrylonitrile-butadiene-styrene and polyamide. 2. The graphene/layered double hydroxide halogen-free flame retardant masterbatch according to claim 1, characterized in that, the layered double hydroxide means that the ideal composition is [N ²⁺ _{1 - x} M ³⁺ _x ·(OH) ₂ ] ^{x +} (A ^h- ) _{x / h} ·mH ₂ O is a typical class of anionic intercalation nanomaterials, where N ²⁺ is a divalent metal ion, including: Mg ²⁺ , Ca ²⁺ , Ba ²⁺ , Fe ²⁺ , Zn ²⁺ , Cu ²⁺ , Cr ²⁺ , Co ²⁺ , Ni ²⁺ ; M ³⁺ is a trivalent metal ion, including Al ³⁺ , Fe ³⁺ ; A is an anion, including NO ₃ ^- , Cl ^- , CO ₃ ^2- , SO ₄ ^2- , abbreviated as N _n M/A-LDH. 3. The graphene/layered double hydroxide halogen-free flame retardant masterbatch according to claim 1, wherein said antioxidant is one of antioxidant 1010, antioxidant 168 or Two;. 4. A method for preparing the graphene/layered double hydroxide halogen-free flame-retardant masterbatch according to any one of claims 1 to 3, characterized in that the specific steps of the method are: the graphene/layer Dry the layered double hydroxide composite at 100°C for 2 hours, add the dried graphene/LDH composite together with the carrier and antioxidant into the high-speed mixer, stir and mix at high speed for 10-30 minutes, and pre-mix to obtain the raw material mixture ; Add the obtained raw material mixture into an extruder, heat, melt and mix, and granulate to obtain a graphene/layered double hydroxide halogen-free flame-retardant masterbatch. 5. the preparation method of graphene/layered double hydroxide halogen-free flame-retardant masterbatch according to claim 4 is characterized in that the preparation method of described graphene/layered double hydroxide compound is: a. Add layered double hydroxide and organic solvent into the reactor according to the mass ratio of 0.05-0.5:1, ultrasonic for 3-24 hours, then centrifuge at 1000-10000r/min for 10-120 minutes, filter and dry to obtain mixture A; b. Add graphene and organic solvent into the reactor at a mass ratio of 0.05-0.5:1, ultrasonicate for 3-24 hours, then centrifuge at 1000-10000r/min for 10-120 minutes, filter, and dry to obtain mixture B; c. Add the mixture A obtained in step a, the mixture B obtained in step b, and the surfactant according to the mass ratio (45-20): (45-20): (40-10) into the reactor and mix evenly, ultrasonic 0.5 ~ 3 hours, and then centrifuged at 1000-5000 r/min for 10-60 minutes, dried and pulverized to obtain a graphene/layered double hydroxide composite. 6. The graphene/layered double hydroxide halogen-free flame retardant masterbatch according to claim 5, characterized in that said surfactant is one or both of silane coupling agents KH550, KH560, KH570 Kind; Described organic solvent is dehydrated alcohol or dimethylformamide (DMF). 7. The preparation method of graphene/layered double hydroxide halogen-free flame retardant masterbatch according to claim 4, is characterized in that described extruder is twin-screw extruder, reciprocating single-screw extruder mixer or internal mixer-a single-screw extruder; the processing temperature of the extruder is 170-245°C.