A calcium carbonate filler masterbatch and its preparation method and application
By pretreating calcium carbonate and preparing calcium carbonate filler masterbatch in two steps, the problem of uneven dispersion of calcium carbonate in EVA foaming material is solved, the fluidity and foaming uniformity of the material are improved, dust pollution is reduced, and material performance is improved.
Patent Information
- Application Number
- CN202310976639.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-08-04
- Publication Date
- 2025-09-12
- Estimated Expiration
- 2043-08-04
Smart Images
Figure QLYQS_1 
Figure QLYQS_2 
Figure BDA0004377495410000021
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of filling masterbatch, in particular to a calcium carbonate filling masterbatch and a preparation method and application thereof. Background Art
[0002] EVA foam refers to a foam material made from EVA and low-density polyethylene (LDPE) with the addition of other additives, then processed through compression or injection molding. Due to its exceptional flexibility, chemical resistance, and excellent elasticity, along with its inherent compatibility and cross-linkability, which other materials lack, EVA foam is widely used in packaging films, gaskets, interior materials, toy materials, sporting goods materials, and building materials. During the preparation of EVA foam, a certain amount of calcium carbonate is typically added as a filler to increase the material's rigidity. Calcium carbonate particles also act as a foaming nucleating agent and thermal conductor, significantly impacting the EVA foaming ratio and uniformity. Uneven dispersion of calcium carbonate particles within the EVA and PE substrates can lead to reduced melt index, poor flowability, uneven foaming, and ultimately low strength and insufficient elasticity. At present, the method of adding calcium carbonate filler in the EVA foaming process is still to add the powder directly. During the mixing process, it is easy for the calcium carbonate to be difficult to feed and unevenly mixed with the resin, which affects the performance of the final foaming material. At the same time, a large amount of dust is generated, causing environmental pollution in the production workshop and other problems.
[0003] To improve the dispersibility of calcium carbonate, organic modifiers are generally used to modify the surface of calcium carbonate. Commonly used modifiers include stearic acid, coupling agents, organic polymers, etc. The selection of surface modifiers is very important. They cannot undergo cross-linking reaction with EVA resin, otherwise it will affect the foaming effect. Therefore, how to improve the dispersibility of calcium carbonate in EVA resin is very important. Summary of the Invention
[0004] The purpose of the present invention is to provide a calcium carbonate filler masterbatch and a preparation method and application thereof, so as to make up for the deficiencies of the prior art.
[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:
[0006] The present invention provides a calcium carbonate filler masterbatch, which is prepared from raw materials containing the following parts by mass:
[0007]
[0008]
[0009] Preferably, it is prepared from raw materials comprising the following parts by mass:
[0010]
[0011] Preferably, the stearate comprises zinc stearate or calcium stearate.
[0012] The present invention provides a method for preparing the calcium carbonate filler masterbatch, comprising the following steps:
[0013] (1) mixing calcium carbonate and polyvinyl acetate emulsion to obtain a primary mixture;
[0014] (2) mixing the obtained primary mixture with low-density polyethylene to obtain a first mixture;
[0015] (3) kneading the obtained first mixture, linear low-density polyethylene and stearate to obtain a second mixture;
[0016] (4) The obtained second mixture and polyethylene wax are mixed and then melt-extruded and granulated in sequence to obtain calcium carbonate filled masterbatch.
[0017] Preferably, in step (1), the mixing temperature is 100-120° C., the rotation speed is 600-800 r / min, and the time is 10-20 min;
[0018] In step (2), the mixing temperature is 120-130° C., the rotation speed is 600-800 r / min, and the mixing time is 10-20 min.
[0019] Preferably, the mixing temperature in step (3) is 120-150° C. and the mixing time is 10-20 min;
[0020] During the melt extrusion process in step (4), the temperature of the processing zone is 160-180°C, and the temperature of the die head is 170-190°C.
[0021] Preferably, the mixing temperature in step (3) is 130-140° C. and the mixing time is 15-17 min;
[0022] During the melt extrusion process in step (4), the temperature of the processing zone is 170-180°C, and the temperature of the die head is 180-190°C.
[0023] The present invention also provides application of the calcium carbonate filling masterbatch in modified EVA foaming material.
[0024] Compared with the prior art, the present invention has the following characteristics:
[0025] 1) In order not to affect the final EVA foaming process, no coupling agent was added, but the masterbatch was still guaranteed to have high filling rate and good fluidity and other performance indicators.
[0026] 2) The filler calcium carbonate is pretreated with polyvinyl acetate emulsion, replacing the titanate or aluminate coupling agent in the traditional formula, which has better compatibility with the substrate polyethylene and EVA, and can obtain a high-flow masterbatch with a filling rate of more than 85% and a melt index flow rate of more than 10.
[0027] 3) Using low-density polyethylene and linear low-density polyethylene as carrier resins, low-density polyethylene is premixed with calcium carbonate particles, and then the premix is mixed with linear low-density polyethylene for extrusion granulation. A high filling rate with a low resin content is achieved using a two-step process. DETAILED DESCRIPTION
[0028] The present invention provides a calcium carbonate filler masterbatch, which is prepared from raw materials containing the following parts by mass:
[0029]
[0030] In the present invention, the low-density polyethylene is preferably 3 to 4 parts, and the brand is preferably 1150A or LD605 or LD165 or 1C7A;
[0031] The linear low-density polyethylene is preferably 3 to 5 parts, more preferably 4 parts, and the brand is preferably 7144, 8916, 7050, 8332 or 3224;
[0032] The stearate is preferably 1 to 1.5 parts;
[0033] The polyvinyl acetate emulsion is preferably 1.2 to 2 parts;
[0034] The polyethylene wax is preferably 1 to 2 parts, and the molecular weight of the polyethylene wax is preferably 1500 to 4500, more preferably 2500 to 3500;
[0035] The calcium carbonate is preferably 85 to 90 parts, preferably 800 to 1250 mesh, and more preferably 1000 to 1100 mesh.
[0036] The present invention provides a method for preparing the calcium carbonate filler masterbatch, comprising the following steps:
[0037] (1) mixing calcium carbonate and polyvinyl acetate emulsion to obtain a primary mixture;
[0038] (2) mixing the obtained primary mixture with low-density polyethylene to obtain a first mixture;
[0039] (3) kneading the obtained first mixture, linear low-density polyethylene and stearate to obtain a second mixture;
[0040] (4) The obtained second mixture and polyethylene wax are mixed and then melt-extruded and granulated in sequence to obtain calcium carbonate filled masterbatch.
[0041] In the present invention, the mixing temperature in step (1) is 100-120°C, preferably 102-115°C, more preferably 105-110°C; the rotation speed is 600-800r / min, preferably 650-700r / min; the time is 10-20min, preferably 15-18min;
[0042] In step (2), the mixing temperature is 120-130° C., preferably 122-127° C., and more preferably 124-125° C.; the rotation speed is 600-800 r / min, preferably 650-700 r / min; and the mixing time is 10-20 min, preferably 15-18 min.
[0043] In the present invention, the mixing temperature in step (3) is 120-150° C., preferably 130-140° C.; the mixing time is 10-20 min, preferably 15-17 min;
[0044] In the melt extrusion process in step (4), the temperature of the processing zone is 160-180° C., preferably 170-180° C.; the temperature of the die head is 170-190° C., preferably 180-190° C.;
[0045] The granulation is preferably water ring pelletizing or strand water-cooled pelletizing.
[0046] The present invention also provides application of the calcium carbonate filling masterbatch in modified EVA foaming material.
[0047] The technical solutions provided by the present invention are described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.
[0048] Example 1
[0049] 1) 880 g of calcium carbonate and 20 g of polyvinyl acetate emulsion were fed into a high-speed mixer at a speed of 650 r / min and stirred at a constant speed at 115° C. for 15 min. The temperature of the high-speed mixer was then raised to 125° C. After the material temperature reached 125° C., 30 g of brand 1150A LDPE resin was added and blended for 10 min to obtain a first mixture;
[0050] 2) The first mixture, 40 g of 7144 type LLDPE resin, and 15 g of zinc stearate were added to an internal mixer at a processing temperature of 135° C. and mixed for 20 min to obtain a second mixture;
[0051] 3) The second mixture and 15 g of PE wax with a molecular weight of 3000 were co-fed into a single-screw extruder. The extruder processing zone temperature was controlled at 175° C., and the extrusion die temperature was controlled at 185° C. After extrusion, the material was extruded and water-ring pelletized. The final masterbatch was then sieved through a vibrating screen to remove fine particles and powder from the masterbatch. The ash content and melt index (MI) of the masterbatch were measured, and the surface smoothness of the masterbatch was observed.
[0052] 4) Weigh 100 g of EVA resin with a 21% ethylene content, 30 g of the calcium carbonate filler masterbatch prepared in 3) above, 3 g of AC (azodicarbonamide) foaming agent, and 1.5 g of zinc oxide. Stir the above materials uniformly in a high-speed blender at 120°C for 15 min. Then, place the mixture in a hydraulic press and foam at 180°C for 20 min. The density and Shore A hardness of the foamed product were measured.
[0053] Comparative Example 1
[0054] In Comparative Example 1, the brand, molecular weight and addition amount of each raw material are the same as those in Example 1, except that the calcium carbonate particles are not pretreated with EVA emulsion and LDPE. The specific process is as follows:
[0055] 1) 880g of calcium carbonate, 20g of polyvinyl acetate emulsion, 30g of brand 1150A LDPE resin, 40g of 7144 LLDPE resin, and 15g of zinc stearate were fed into a high-speed mixer at a speed of 650r / min and stirred at a constant speed for 15min at a temperature of 115°C to obtain a first mixture.
[0056] 2) adding the first mixture into an internal mixer, controlling the processing temperature at 135° C., and mixing for 20 minutes to obtain a second mixture;
[0057] 3) The second mixture and 15 g of PE wax with a molecular weight of 3000 were co-fed into a single-screw extruder. The extruder processing zone temperature was controlled at 175° C., and the extrusion die temperature was controlled at 185° C. After extrusion, the material was extruded and water-ring pelletized. The final masterbatch was then sieved through a vibrating screen to remove fine particles and powder from the masterbatch. The ash content and melt index (MI) of the masterbatch were measured, and the surface smoothness of the masterbatch was observed.
[0058] 4) Weigh 100 g of EVA resin with a 21% ethylene content, 30 g of the calcium carbonate filler masterbatch prepared in 3) above, 3 g of AC (azodicarbonamide) foaming agent, and 1.5 g of zinc oxide. Stir the above materials uniformly in a high-speed blender at 120°C for 15 min. Then, place the mixture in a hydraulic press and foam at 180°C for 20 min. The density and Shore A hardness of the foamed product were measured.
[0059] Comparative Example 2
[0060] Comparative Example 2 differs from Example 1 in that the polyvinyl acetate emulsion is replaced with an aluminate coupling agent to pretreat the calcium carbonate, and the indicators of the final masterbatch and the hardness and density of the foamed product are tested.
[0061] 1) 880 g of calcium carbonate and 20 g of polyvinyl acetate emulsion were fed into a high-speed mixer at a speed of 650 r / min and stirred at a constant speed at 115° C. for 15 min. The temperature of the high-speed mixer was then raised to 125° C. After the material temperature reached 125° C., 30 g of brand 1150A LDPE resin was added and blended for 10 min to obtain a first mixture;
[0062] 2) The first mixture, 40 g of 7144 type LLDPE resin, and 15 g of zinc stearate were added to an internal mixer at a processing temperature of 135° C. and mixed for 20 min to obtain a second mixture;
[0063] 3) The second mixture and 15 g of PE wax with a molecular weight of 3000 were co-fed into a single-screw extruder. The extruder processing zone temperature was controlled at 175° C., and the extrusion die temperature was controlled at 185° C. After extrusion, the material was extruded and water-ring pelletized. The final masterbatch was then sieved through a vibrating screen to remove fine particles and powder from the masterbatch. The ash content and melt index (MI) of the masterbatch were measured, and the surface smoothness of the masterbatch was observed.
[0064] 4) Weigh 100 g of EVA resin with a 21% ethylene content, 30 g of the calcium carbonate filler masterbatch prepared in 3) above, 3 g of AC (azodicarbonamide) foaming agent, and 1.5 g of zinc oxide. Stir the above materials uniformly in a high-speed blender at 120°C for 15 min. Then, place the mixture in a hydraulic press and foam at 180°C for 20 min. The density and Shore A hardness of the foamed product were measured.
[0065] Comparative Example 3
[0066] The difference from Example 1 is that the calcium carbonate powder pretreated with EVA is not pre-coated with LDPE in advance. The calcium carbonate is directly mixed with LDPE and LLDPE to form granules in a one-step method, and the index performance of the final masterbatch and foamed product is measured. The preparation steps are as follows:
[0067] 1) adding 880 g of calcium carbonate and 20 g of polyvinyl acetate emulsion into a high-speed mixer at a speed of 650 r / min and stirring at a constant speed for 15 min at a temperature of 115° C. to obtain a first mixture;
[0068] 2) The first mixture, 40 g of 7144 type LLDPE resin, 30 g of brand 1150A type LDPE resin, and 15 g of zinc stearate were fed into an internal mixer at a processing temperature of 135° C. and mixed for 20 minutes to obtain a second mixture;
[0069] 3) The second mixture and 15 g of PE wax with a molecular weight of 3000 were co-fed into a single-screw extruder. The extruder processing zone temperature was controlled at 175° C., and the extrusion die temperature was controlled at 185° C. After extrusion, the material was extruded and water-ring pelletized. The final masterbatch was then sieved through a vibrating screen to remove fine particles and powder from the masterbatch. The ash content and melt index (MI) of the masterbatch were measured, and the surface smoothness of the masterbatch was observed.
[0070] 4) Weigh 100 g of EVA resin with a 21% ethylene content, 30 g of the calcium carbonate filler masterbatch prepared in 3) above, 3 g of AC (azodicarbonamide) foaming agent, and 1.5 g of zinc oxide. Stir the above materials uniformly in a high-speed blender at 120°C for 15 min. Then, place the mixture in a hydraulic press and foam at 180°C for 20 min. The density and Shore A hardness of the foamed product were measured.
[0071] Comparative Example 4
[0072] The difference from the embodiment is that in this comparative example, the same mass fraction of calcium carbonate and related additives are added to replace the calcium carbonate filler masterbatch when preparing EVA foam products, and the effects of directly adding calcium carbonate powder and adding calcium carbonate filler masterbatch on the performance of the final foamed product are compared.
[0073] Weigh 100g of EVA resin with an ethylene content of 21%, 26g of 1250 mesh calcium carbonate powder, 20g of polyvinyl acetate emulsion, 30g of brand 1150A type LDPE resin, 40g of 7144 type LLDPE resin, 15g of zinc stearate, 15g of PE wax with a molecular weight of 3000, 3g of foaming agent AC (azodicarbonamide), and 1.5g of zinc oxide. After the above materials are uniformly stirred at a temperature of 120°C in a high-speed stirrer for 15min, they are put into an oil press and foamed at a temperature of 180°C for 20min. The density and Shore A hardness of the foamed product are measured.
[0074] Example 2
[0075] 1) 880 g of calcium carbonate and 20 g of polyvinyl acetate emulsion were fed into a high-speed mixer at a speed of 650 r / min and stirred at a constant speed at 115° C. for 15 min. The temperature of the high-speed mixer was then raised to 125° C. After the material temperature reached 125° C., 30 g of LD605 LDPE resin was added and blended for 10 min to obtain a first mixture;
[0076] 2) The first mixture, 40 g of 8332 LLDPE resin, and 15 g of zinc stearate were added to an internal mixer at a temperature of 135° C. for 20 min to obtain a second mixture;
[0077] 3) The second mixture and 15 g of PE wax with a molecular weight of 3000 were fed together into a single-screw extruder. The extruder processing zone temperature was controlled at 175° C., and the extrusion die temperature was controlled at 185° C. After processing in the extruder, the material was extruded and water-cooled into strands and pelletized. The final masterbatch was then sieved through a vibrating screen to remove fine particles and powder from the masterbatch. The ash content and melt index (MI) of the masterbatch were tested, and the surface smoothness of the masterbatch was observed.
[0078] 4) Weigh 100 g of EVA resin with a 21% ethylene content, 30 g of the calcium carbonate filler masterbatch prepared in 3) above, 3 g of AC (azodicarbonamide) foaming agent, and 1.5 g of zinc oxide. Stir the above materials uniformly in a high-speed blender at 120°C for 15 min. Then, place the mixture in a hydraulic press and foam at 180°C for 20 min. The density and Shore A hardness of the foamed product were measured.
[0079] Example 3
[0080] 1) 890 g of calcium carbonate and 20 g of polyvinyl acetate emulsion were fed into a high-speed mixer at a speed of 650 r / min and stirred at a constant speed at 115° C. for 15 min. The temperature of the high-speed mixer was then raised to 125° C. After the material temperature reached 125° C., 30 g of LD605 LDPE resin was added and blended for 10 min to obtain a first mixture;
[0081] 2) The first mixture, 35 g of 8332 LLDPE resin, and 12 g of zinc stearate were added to an internal mixer at a temperature of 135° C. for 20 min to obtain a second mixture;
[0082] 3) The second mixture and 13 g of PE wax with a molecular weight of 3000 were fed together into a single-screw extruder. The extruder processing zone temperature was controlled at 175° C., and the extrusion die temperature was controlled at 185° C. After processing in the extruder, the material was extruded and water-cooled into strands and pelletized. The final masterbatch was then sieved through a vibrating screen to remove fine particles and powder from the masterbatch. The ash content and melt index (MI) of the masterbatch were tested, and the surface smoothness of the masterbatch was observed.
[0083] 4) Weigh 100 g of EVA resin with a 21% ethylene content, 30 g of the calcium carbonate filler masterbatch prepared in 3) above, 3 g of AC (azodicarbonamide) foaming agent, and 1.5 g of zinc oxide. Stir the above materials uniformly in a high-speed blender at 120°C for 15 min. Then, place the mixture in a hydraulic press and foam at 180°C for 20 min. The density and Shore A hardness of the foamed product were measured.
[0084] Example 4
[0085] 1) 900 g of calcium carbonate and 20 g of polyvinyl acetate emulsion were fed into a high-speed mixer at a speed of 650 r / min and stirred at a constant speed at 115° C. for 15 min. The temperature of the high-speed mixer was then raised to 125° C. After the material temperature reached 125° C., 30 g of LD605 LDPE resin was added and blended for 10 min to obtain a first mixture;
[0086] 2) The first mixture, 30 g of 8332 LLDPE resin, and 10 g of zinc stearate were added to an internal mixer at a temperature of 135° C. for 20 min to obtain a second mixture;
[0087] 3) The second mixture and 10 g of PE wax with a molecular weight of 3000 were fed together into a single-screw extruder. The extruder processing zone temperature was controlled at 175° C., and the extrusion die temperature was controlled at 185° C. After processing in the extruder, the material was extruded and water-cooled into strands and pelletized. The final masterbatch was then sieved through a vibrating screen to remove fine particles and powder from the masterbatch. The ash content and melt index (MI) of the masterbatch were tested, and the surface smoothness of the masterbatch was observed.
[0088] 4) Weigh 100 g of EVA resin with a 21% ethylene content, 30 g of the calcium carbonate filler masterbatch prepared in 3) above, 3 g of AC (azodicarbonamide) foaming agent, and 1.5 g of zinc oxide. Stir the above materials uniformly in a high-speed blender at 120°C for 15 min. Then, place the mixture in a hydraulic press and foam at 180°C for 20 min. The density and Shore A hardness of the foamed product were measured.
[0089] Table 1 Performance of each embodiment and comparative example product
[0090]
[0091] The present invention adopts EVA emulsion to carry out coating and modification treatment on calcium carbonate particles, reduces the adverse effect of the use of a coupling agent on a subsequent foaming process, improves the compatibility of the calcium carbonate particles with a PE resin, and simultaneously adopts a two-step method to prepare a masterbatch, thereby increasing the calcium carbonate content in the masterbatch, and obtaining a calcium carbonate-filled masterbatch with a smooth surface and good fluidity. The masterbatch is applied to EVA foaming, so that the foamed product can obtain a lower density and a higher foaming rate (low hardness).
[0092] Through experimental application tests, the results of Example 1 and Comparative Example 4 show that, in the EVA foaming process, preparing calcium carbonate powder into a calcium carbonate filler masterbatch with excellent dispersibility can obtain a product with better foaming effect than directly adding calcium carbonate powder; the results of Example 1 and Comparative Example 2 show that using EVA emulsion to replace the aluminate coupling agent in the conventional masterbatch formula can not only obtain a masterbatch with a better filling rate, but also help to obtain EVA products with a higher foaming ratio; the results of Example 1 and Comparative Examples 1 and 3 show that the segmented pretreatment of calcium carbonate with EVA emulsion and LDPE has a positive effect on the fluidity and dispersibility of the final masterbatch.
[0093] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.
Claims
1. A calcium carbonate filler masterbatch, characterized in that: Prepared from the following raw materials in parts by weight: The preparation method of the calcium carbonate filling masterbatch comprises the following steps: (1) mixing calcium carbonate and polyvinyl acetate emulsion to obtain a primary mixture; (2) mixing the obtained primary mixture with low-density polyethylene to obtain a first mixture; (3) kneading the obtained first mixture, linear low-density polyethylene and stearate to obtain a second mixture; (4) The obtained second mixture and polyethylene wax are mixed and then melt-extruded and granulated in sequence to obtain calcium carbonate filled masterbatch.
2. The calcium carbonate filler masterbatch according to claim 1, characterized in that Prepared from the following raw materials in parts by weight: 。 3. The calcium carbonate filled masterbatch according to claim 1 or 2, characterized in that The stearate comprises zinc stearate or calcium stearate.
4. The method for preparing the calcium carbonate filler masterbatch according to any one of claims 1 to 3, characterized in that: The following steps are included: (1) mixing calcium carbonate and polyvinyl acetate emulsion to obtain a primary mixture; (2) mixing the obtained primary mixture with low-density polyethylene to obtain a first mixture; (3) kneading the obtained first mixture, linear low-density polyethylene and stearate to obtain a second mixture; (4) The obtained second mixture and polyethylene wax are mixed and then melt-extruded and granulated in sequence to obtain calcium carbonate filled masterbatch.
5. The preparation method according to claim 4, characterized in that In step (1), the mixing temperature is 100-120° C., the rotation speed is 600-800 r / min, and the time is 10-20 min; In step (2), the mixing temperature is 120-130° C., the rotation speed is 600-800 r / min, and the mixing time is 10-20 min.
6. The preparation method according to claim 4 or 5, characterized in that The mixing temperature in step (3) is 120-150° C. and the mixing time is 10-20 min; During the melt extrusion process in step (4), the temperature of the processing zone is 160-180°C, and the temperature of the die head is 170-190°C.
7. The preparation method according to claim 6, characterized in that The mixing temperature in step (3) is 130-140° C. and the mixing time is 15-17 min; During the melt extrusion process in step (4), the temperature of the processing zone is 170-180°C, and the temperature of the die head is 180-190°C.
8. Use of the calcium carbonate filler masterbatch according to any one of claims 1 to 3 in modified EVA foaming materials.
Citation Information
Patent Citations
Preparation method of calcium carbonate packed masterbatch
CN105219113A
Polymer modified nano calcium carbonate novel product series
CN109867986A