Carrier-free carbon black master batch and preparation method thereof

Abstract

The invention provides a carrier-free carbon black master batch which is prepared by the following steps: (1) adding carbon black, a hyperdispersant and an organic silicon monomer DMC into a reactor in proportion, and dispersing; (2) after the carbon black is completely dispersed, adding an end-capping reagent and an initiator, uniformly mixing, heating, carrying out polymerization reaction for 4-8 hours, after the reaction is finished, starting vacuum to remove low components, cooling and discharging to obtain polydimethylsiloxane coated carbon black; and (3) uniformly mixing the polydimethylsiloxane coated carbon black with a dispersing agent in proportion, kneading into powder by using a kneading machine, and granulating to obtain the carrier-free carbon black master batch. The invention also provides a preparation method of the carrier-free carbon black master batch. The carrier-free carbon black master batch does not contain a plastic resin carrier, so that the dispersion of the carbon black is further improved, and the use universality of the carbon black master batch is improved.

Description

Technical Field

[0001] The invention belongs to the field of polymer materials, and more specifically, relates to a carrier-free carbon black masterbatch and a preparation method thereof. Background Art

[0002] As a commonly used black pigment and filler, carbon black is widely used in plastics, rubber, coatings, inks and other industries. In the plastics industry, carbon black is widely used as a pigment and stabilizer due to its superior tinting power, UV absorption performance and anti-UV aging performance. Masterbatch is the most commonly used additive in plastic processing. It is usually a plastic colorant dispersed by a certain proportion of pigment / dye, dispersant and thermoplastic resin carrier. The traditional method of preparing carbon black masterbatch usually uses thermoplastic polymers such as polyolefin, polyamide, polycarbonate, ABS as carriers, and mixes carbon black with resin by physical mixing. However, due to the small particle size of carbon black, usually at the nanometer level, the van der Waals force between particles is very high, and the carbon black powder is very easy to agglomerate together, which greatly affects the dispersion of carbon black. When preparing carbon black masterbatch, the dispersion of carbon black is also very important.

[0003] In the plastic processing, the dispersion of carbon black is directly related to the gloss, color uniformity and physical and mechanical properties of the product. The aggregation of carbon black particles will cause pitting on the surface of the product, affecting the appearance quality and reducing the strength and weather resistance of the product.

[0004] In addition, the original particle size, structure and surface properties of carbon black also have an important influence on its dispersibility. The smaller the particle size, the larger the specific surface area, the stronger the van der Waals force between carbon black particles, and the more difficult it is to disperse. Therefore, how to improve the dispersibility of carbon black without sacrificing performance is an urgent problem to be solved in the preparation technology of carbon black masterbatch. Summary of the invention

[0005] In order to solve the above problems, the present invention provides a carrier-free carbon black masterbatch and a preparation method thereof, which does not contain a plastic resin carrier, further improves the dispersion of carbon black, and improves the versatility of the use of the carbon black masterbatch.

[0006] In order to better solve the above problems, the present invention adopts the following technical solutions:

[0007] A carrier-free carbon black masterbatch, wherein the carrier-free carbon black masterbatch is prepared by the following steps:

[0008] (1) adding carbon black, hyperdispersant, and organosilicon monomer DMC into a reactor in proportion and dispersing;

[0009] (2) After the carbon black is completely dispersed, add the end-capping agent and the initiator, mix well, increase the temperature, and perform the polymerization reaction for 4-8 hours. After the reaction is completed, open the vacuum to remove the components, cool down and discharge the material to obtain the carbon black coated with polydimethylsiloxane;

[0010] (3) The carbon black coated with polydimethylsiloxane and the dispersant are uniformly mixed in proportion, kneaded into powder by a kneader, and granulated into the carrier-free carbon black masterbatch.

[0011] As a preferred technical solution, the carbon black, the hyperdispersant, and the organosilicon monomer DMC are used in a mass ratio of (4-8):(0.01-0.2):(5-10).

[0012] As a preferred technical solution, the temperature for the polymerization reaction in step (2) is 80-120°C.

[0013] As a preferred technical solution, the mass ratio of the organosilicon monomer DMC to the end-capping agent and the initiator is 100:(0.05-0.5):(0.01-0.03).

[0014] As a preferred technical solution, the carbon black particle size is 5-50nm.

[0015] As a preferred technical solution, the hyperdispersant is one or a mixture of soaps, sulfates, and sulfonates.

[0016] As a preferred technical solution, the organosilicon monomer DMC is a mixture of dimethylsiloxane ring bodies D3, D4, D5, and D6, wherein the mass content of D4 is above 80%.

[0017] As a preferred technical solution, the end-capping agent in step (2) is one of hexamethyldisiloxane, tetramethyldihydrogendisiloxane, and tetramethyldivinyldisiloxane.

[0018] As a preferred technical solution, the dispersant described in step (3) is one or a mixture of PETS, PE wax, PP wax, EBS, E wax, OP wax, and S wax.

[0019] The present application also provides a method for preparing a carrier-free carbon black masterbatch as described in any one of the above, comprising the following steps:

[0020] (1) adding carbon black, hyperdispersant, and organosilicon monomer DMC into a reactor in proportion and dispersing;

[0021] (2) After the carbon black is completely dispersed, add the end-capping agent and the initiator, mix well, increase the temperature, and perform the polymerization reaction for 4-8 hours. After the reaction is completed, open the vacuum to remove the components, cool down and discharge the material to obtain the carbon black coated with polydimethylsiloxane;

[0022] (3) The carbon black coated with polydimethylsiloxane and the dispersant are uniformly mixed in proportion, kneaded into powder by a kneader, and granulated into the carrier-free carbon black masterbatch.

[0023] The beneficial effect of the present invention is that carbon black and organosilicon DMC monomers are directly polymerized to prepare polydimethylsiloxane-coated carbon black, and this coating structure helps to improve the dispersibility and weather resistance of carbon black. At the same time, the glossiness is improved, and it does not contain plastic resin carriers, has universality, and can be used in a variety of plastic processing without being restricted by carriers. In particular, it is applied to high-gloss products such as PA, ABS, PC, PMMA, etc., and the surface of the products has high blackness, high gloss, and no pitting. DETAILED DESCRIPTION

[0024] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in combination with specific descriptions and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0025] There are many carbon black masterbatch carriers. Different plastic processing requires different types of carbon black masterbatch. It is difficult to distinguish them when using them, and switching is troublesome. In addition, it is also difficult to disperse carbon black well with existing technology. When using it, problems such as pitting, high addition amount, and poor thermal aging will occur. To solve this problem, the present application provides a carrier-free carbon black masterbatch and a preparation method thereof. Among them, the carrier-free carbon black masterbatch is prepared by the following steps: (1) adding carbon black, super dispersant, and silicone monomer DMC to a reactor in proportion and dispersing; (2) after the carbon black is completely dispersed, adding a capping agent and an initiator, mixing evenly, heating, and polymerizing for 4-8 hours. After the reaction is completed, open the vacuum to remove the lower components, cool and discharge the material to obtain polydimethylsiloxane-coated carbon black; (3) mixing the polydimethylsiloxane-coated carbon black and the dispersant in proportion, kneading them into powder with a kneader, and granulating them into the carrier-free carbon black masterbatch.

[0026] In the preparation process of the carbon black masterbatch, carbon black and organosilicon DMC monomers are directly polymerized to prepare polydimethylsiloxane-coated carbon black. This coating structure helps to improve the dispersion and weather resistance of carbon black. At the same time, it improves the glossiness, does not contain plastic resin carriers, has versatility, and can be used in a variety of plastic processing without being restricted by carriers. In particular, it is used in high-gloss products such as PA, ABS, PC, PMMA, etc. The surface of the product has high blackness, high gloss, and no pitting.

[0027] Specifically, in one embodiment, the carrier-free carbon black masterbatch is prepared by the following steps:

[0028] (1) Carbon black, a hyperdispersant, and an organosilicon monomer DMC are simultaneously added into a reactor in a mass ratio of (4-8):(0.01-0.2):(5-10), and ultrasonically dispersed for 10-90 minutes;

[0029] (2) After the carbon black is completely dispersed, add the end-capping agent and the initiator, mix them evenly, raise the temperature to 80-120° C., and carry out the polymerization reaction for 4-8 hours. After the reaction is completed, open the vacuum to below -0.1 MPa to remove the low components, cool down and discharge the material to obtain the carbon black coated with polydimethylsiloxane; wherein the mass ratio of the organosilicon monomer DMC to the end-capping agent and the initiator is 100:(0.05-0.5):(0.01-0.03);

[0030] (3) The polydimethylsiloxane-coated carbon black and the dispersant are mixed uniformly in proportion and kneaded into powder by a kneader, and granulated into carbon black masterbatch by hot cutting on the air-cooled die surface of a single-screw extruder.

[0031] As a preferred technical solution, the carbon black particle size is 5-50nm; further preferably 15-25nm.

[0032] As a preferred technical solution, the hyperdispersant is one or a mixture of soaps, sulfates, and sulfonates; more preferably soaps; and even more preferably sodium dodecylbenzene sulfonate and sodium stearate.

[0033] As a preferred technical solution, the organosilicon monomer DMC is a mixture of dimethylsiloxane ring bodies D3, D4, D5, and D6, wherein the mass content of D4 is above 80%; further preferably, the mass content of D4 is above 95%.

[0034] As a preferred technical solution, the end-capping agent in step (2) is one of hexamethyldisiloxane, tetramethyldihydrogendisiloxane and tetramethyldivinyldisiloxane; more preferably, tetramethyldihydrogendisiloxane.

[0035] As a preferred technical solution, the initiator described in step (2) is one of tetramethylammonium hydroxide and potassium hydroxide; more preferably, tetramethylammonium hydroxide.

[0036] As a preferred technical solution, the dispersant described in step (3) is one or a mixture of PETS (pentaerythritol stearate), PE wax, PP wax, EBS, E wax, OP wax, and S wax; further preferred are PETS, PE wax, and EBS; and even more preferred is PETS.

[0037] The technical solution of the present application is further described below in conjunction with the embodiments:

[0038] Example 1

[0039] A carrier-free carbon black masterbatch and a preparation method thereof, comprising the following steps:

[0040] (1) Cabot Monarch 800 carbon black (particle size 17 nm), sodium dodecylbenzene sulfonate hyperdispersant, and silicone monomer DMC (D4 mass content 90%) were added into a reactor at a mass ratio of 4:0.2:6, and ultrasonically dispersed at 600 W and 30 kHz for 30 min;

[0041] (2) After the carbon black is completely dispersed, tetramethyl dihydrogen disiloxane capping agent and tetramethyl ammonium hydroxide initiator are added, mixed evenly, heated to 85°C, and polymerized for 6 hours. After the reaction is completed, vacuum is turned on below -0.1MPa to remove low components, and the temperature is lowered to 40°C to obtain polydimethylsiloxane-coated carbon black; wherein the mass ratio of the organosilicon monomer DMC to the capping agent and the initiator is 100:0.05:0.02;

[0042] (3) The carbon black coated with polydimethylsiloxane and PETS are mixed uniformly in a mass ratio of 2:1, kneaded into powder by a kneader, and granulated into carrier-free carbon black masterbatch by hot cutting on the air-cooled die surface of a single-screw extruder.

[0043] Example 2

[0044] A carrier-free carbon black masterbatch and a preparation method thereof, comprising the following steps:

[0045] (1) Cabot Monarch 900 carbon black (particle size 15 nm), sodium dodecylbenzene sulfonate hyperdispersant, and silicone monomer DMC (D4 mass content 95%) were added into a reactor at a mass ratio of 4:0.1:5, and ultrasonically dispersed at 800 W and 50 kHz for 30 min;

[0046] (2) After the carbon black is completely dispersed, tetramethyl dihydrogen disiloxane capping agent and tetramethyl ammonium hydroxide initiator are added, mixed evenly, heated to 85°C, and polymerized for 6 hours. After the reaction is completed, vacuum is turned on below -0.1MPa to remove low components, and the temperature is lowered to 40°C to obtain polydimethylsiloxane-coated carbon black; wherein the mass ratio of the organosilicon monomer DMC to the capping agent and the initiator is 100:0.03:0.02;

[0047] (3) The carbon black coated with polydimethylsiloxane and PETS are mixed uniformly in a mass ratio of 2:1, kneaded into powder by a kneader, and granulated into carrier-free carbon black masterbatch by hot cutting on the air-cooled die surface of a single-screw extruder.

[0048] Example 3

[0049] An easily dispersible, high-gloss, universal carbon black masterbatch and a preparation method thereof, comprising the following steps:

[0050] (1) Cabot Monarch 900 carbon black (particle size 15 nm), sodium stearate hyperdispersant, and silicone monomer DMC (D4 mass content 95%) were added into a reactor at a mass ratio of 4:0.5:5, and ultrasonically dispersed at 800 W and 50 kHz for 30 min;

[0051] (2) After the carbon black is completely dispersed, tetramethyl dihydrogen disiloxane capping agent and tetramethyl ammonium hydroxide initiator are added, mixed evenly, heated to 85°C, and polymerized for 4 hours. After the reaction is completed, vacuum is turned on below -0.1MPa to remove low components, and the temperature is lowered to 40°C to obtain polydimethylsiloxane-coated carbon black; wherein the mass ratio of the organosilicon monomer DMC to the capping agent and the initiator is 100:0.03:0.04;

[0052] (3) The polydimethylsiloxane-coated carbon black and PETS are mixed uniformly in a mass ratio of 3:1 and kneaded into powder using a kneader, and then granulated into carbon black masterbatch using an air-cooled die face of a single-screw extruder.

[0053] Example 4

[0054] An easily dispersible, high-gloss, universal carbon black masterbatch and a preparation method thereof, comprising the following steps:

[0055] (1) Cabot Monarch 900 carbon black (particle size 15 nm), sodium stearate hyperdispersant, and silicone monomer DMC (D4 mass content 95%) were added into a reactor at a mass ratio of 4:0.5:6, and ultrasonically dispersed at 1 KW and 65 KHz for 50 min;

[0056] (2) After the carbon black is completely dispersed, tetramethyl dihydrogen disiloxane capping agent and tetramethyl ammonium hydroxide initiator are added, mixed evenly, heated to 85°C, and polymerized for 4 hours. After the reaction is completed, vacuum is turned on below -0.1MPa to remove low components, and the temperature is lowered to 40°C to obtain polydimethylsiloxane-coated carbon black; wherein the mass ratio of the organosilicon monomer DMC to the capping agent and the initiator is 100:0.05:0.02;

[0057] (3) The polydimethylsiloxane-coated carbon black and PETS are mixed uniformly in a mass ratio of 3:1 and kneaded into powder using a kneader, and then granulated into carbon black masterbatch using an air-cooled die face of a single-screw extruder.

[0058] The carbon black masterbatch prepared in the above embodiment and the carbon black masterbatch of the control group are applied to different plastic polymer resin systems such as PP, PA, ABS, PC, etc., wherein the carbon black masterbatch of the control group is a carbon black masterbatch of a resin carrier with good compatibility.

[0059] Table 1 is the comparative data of the application of the embodiment and the comparative example (Cabot black masterbatch UN2014, commercially available) in PP resin (manufacturer model: Yangzi Petrochemical PP-YPJ-1215C). The carbon black content of the embodiment and the comparative example is 1% and added to the resin. The twin-screw extruder is used for extrusion granulation at 180-220°C, and the standard force performance specimens and color plates with a length, width and thickness of 6cm*4cm*4mm are injection molded at 190-220°C.

[0060] Table 2 is the comparative data of the application of the embodiment and the comparative example (Cabot black masterbatch PA3785, commercially available) in PA6 resin (manufacturer model: Hangzhou Polyshun PA6-J2800). The carbon black content of the embodiment and the comparative example is 1% and added to the resin. The twin-screw extruder is used for extrusion granulation at 230-250°C, and the standard force performance specimens and color plates with a length, width and thickness of 6cm*4cm*4mm are injection molded at 230-250°C.

[0061] Table 3 is the comparative data of the application of the embodiment and the comparative example (Cabot black masterbatch SA3176, commercially available) in ABS resin (manufacturer model: ABS-AG15A1). The carbon black content of the embodiment and the comparative example is 1% and added to the resin. The twin-screw extruder is used for extrusion granulation at 210-230°C, and the standard force performance specimens and color plates with a length, width and thickness of 6cm*4cm*4mm are injection molded at 210-230°C.

[0062] Table 4 is the comparative data of the application of the embodiment and the comparative example (Cabot black masterbatch EG3807, commercially available) in PC resin (manufacturer model: Japan Idemitsu PC-FN2200). The carbon black content of the embodiment and the comparative example is 1% and added to the resin. The pelletization is performed by extrusion at 250-270°C using a twin-screw extruder, and the standard force performance specimens and color plates with a length, width and thickness of 6cm*4cm*4mm are injection molded at 250-270°C.

[0063] The performance test method and test results are as follows:

[0064] Mechanical properties test: The tensile properties test was carried out according to ISO527-2-2019, the sample size was 170×10×4mm, and the tensile speed was 50mm / min.

[0065] The bending performance test was carried out according to ISO178-2019, with a sample size of 80×10×4mm, a bending speed of 2mm / min, and a span of 64mm.

[0066] The notched cantilever beam impact strength test was carried out according to ISO179-2010, the specimen size was 80×6×4 mm, and the notch depth was one third of the specimen thickness.

[0067] Gloss test: Gloss test is carried out according to GB / T 8807-1988 plastic mirror gloss test method, and the test angle is 60°.

[0068] Table 1

[0069]

[0070] From the test results in Table 1, compared with the comparative example, the carbon black masterbatch prepared by the present invention has basically the same hue when applied to the PP system, has higher glossiness, and has higher impact strength among the mechanical properties.

[0071] Table 2

[0072]

[0073] From the test results in Table 2, compared with the comparative example, the carbon black masterbatch prepared by the present invention has basically the same hue and mechanical properties when applied to the PA system, and has higher gloss.

[0074] Table 3

[0075]

[0076] From the test results in Table 3, compared with the comparative example, the carbon black masterbatch prepared by the present invention has basically the same hue and mechanical properties when applied to the ABS system, and has higher gloss.

[0077] Table 4

[0078]

[0079] From the test results in Table 4, compared with the comparative example, the carbon black masterbatch prepared by the present invention has basically the same hue and mechanical properties when applied to the PC system, and has higher gloss.

[0080] From the data in Table 1, Table 2, Table 3 and Table 4, in the PP, PA, ABS and PC systems, the hue value of the uncarrier carbon black masterbatch is basically consistent with that of the comparative example; in terms of glossiness, the uncarrier carbon black masterbatch shows higher glossiness; in terms of mechanical properties, the uncarrier carbon black masterbatch has higher impact strength in each resin system. The uncarrier carbon black masterbatch prepared by the present invention adds carbon black during the silicone polymerization reaction, and further disperses the agglomerated carbon black particles into smaller particle sizes through a superdispersant and ultrasonic dispersion process, thereby improving the dispersion effect of carbon black. In addition, the polymerized silicone and wax dispersants further improve the glossiness of the resin surface.

[0081] In general, compared with the common carbon black masterbatch using resin as a carrier, the carbon black masterbatch prepared by the present invention has better carbon black dispersion effect and is more versatile in application.

[0082] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A carrier-free carbon black masterbatch, characterized in that: The carrier-free carbon black masterbatch is prepared by the following steps: (1) adding carbon black, hyperdispersant, and organosilicon monomer DMC into a reactor in proportion and dispersing; (2) After the carbon black is completely dispersed, add the end-capping agent and the initiator, mix well, increase the temperature, and perform the polymerization reaction for 4-8 hours. After the reaction is completed, open the vacuum to remove the components, cool down and discharge the material to obtain the carbon black coated with polydimethylsiloxane; (3) The carbon black coated with polydimethylsiloxane and the dispersant are uniformly mixed in proportion, kneaded into powder by a kneader, and granulated into the carrier-free carbon black masterbatch.

2. The carrier-free carbon black masterbatch according to claim 1, characterized in that The carbon black, the super dispersant and the organosilicon monomer DMC are used in a mass ratio of (4-8):(0.01-0.2):(5-10).

3. The carrier-free carbon black masterbatch according to claim 1, characterized in that The temperature for the polymerization reaction in step (2) is 80-120°C.

4. The carrier-free carbon black masterbatch according to claim 1, characterized in that The mass ratio of the organosilicon monomer DMC to the end-capping agent and the initiator is 100:(0.05-0.5):(0.01-0.03).

5. The carrier-free carbon black masterbatch according to claim 1, characterized in that The carbon black particle size is 5-50nm.

6. The carrier-free carbon black masterbatch according to claim 1, characterized in that The hyperdispersant is one or a mixture of soaps, sulfates, and sulfonates.

7. The carrier-free carbon black masterbatch according to claim 1, characterized in that The organosilicon monomer DMC is a mixture of dimethylsiloxane ring bodies D3, D4, D5 and D6, wherein the mass content of D4 is above 80%.

8. The carrier-free carbon black masterbatch according to claim 1, characterized in that The end-capping agent described in step (2) is one of hexamethyldisiloxane, tetramethyldihydrogendisiloxane and tetramethyldivinyldisiloxane.

9. The carrier-free carbon black masterbatch according to claim 1, characterized in that The dispersant described in step (3) is one or a mixture of PETS, PE wax, PP wax, EBS, E wax, OP wax and S wax.

10. A method for preparing the carrier-free carbon black masterbatch according to any one of claims 1 to 9, characterized in that: The following steps are involved: (1) adding carbon black, hyperdispersant, and organosilicon monomer DMC into a reactor in proportion and dispersing; (2) After the carbon black is completely dispersed, add the end-capping agent and the initiator, mix well, increase the temperature, and perform the polymerization reaction for 4-8 hours. After the reaction is completed, open the vacuum to remove the components, cool down and discharge the material to obtain the carbon black coated with polydimethylsiloxane; (3) The carbon black coated with polydimethylsiloxane and the dispersant are uniformly mixed in proportion, kneaded into powder by a kneader, and granulated into the carrier-free carbon black masterbatch.

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