High-calcium filled composite modified material, and preparation method and application thereof

Abstract

This invention discloses a high-calcium filled composite modified material, comprising a matrix resin, a filler, an elastomer, an interface modifier, and additives. The elastomer is a blend of EPDM rubber and POE polyolefin elastomer, and the interface modifier is a blend of titanate coupling agent and aluminate coupling agent. The weight ratio of the matrix resin, filler, elastomer, interface modifier, and additives is 15-18:75-78:4-5:2.0-2.5:2.2-3.1. The advantages of this invention compared to existing technologies are: it provides a high-calcium filled composite modified material, its preparation method, and its application, ensuring material performance, adapting the process to existing mass production lines, and significantly reducing raw material costs.

Description

Technical Field

[0001] This invention relates to the field of polymer modified materials technology, specifically to a high-calcium filled composite modified material and its preparation method and application. Background Technology

[0002] Polypropylene (PP) modified materials are widely used in automobiles, home appliances, new energy and other fields due to their advantages such as light weight, corrosion resistance and easy processing.

[0003] However, traditional modified PP materials have a high resin matrix content and the filler content is usually less than 50%, resulting in high material costs and making it difficult to meet the demand for low-cost materials in fields such as new energy and home appliances.

[0004] However, when attempting to increase the calcium carbonate filler content to 75% or more, problems such as filler agglomeration and poor compatibility with the resin matrix are likely to occur, which in turn leads to a significant decrease in the mechanical properties of the material, such as tensile strength and impact strength. At the same time, the processing fluidity is significantly reduced, making it impossible to achieve stable large-scale production.

[0005] In the existing technology, there is a lack of modified material systems that can balance mechanical properties, processing performance, and compatibility with existing production lines while maintaining 75%-78% ultra-high calcium content. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to overcome the above-mentioned technical defects and provide a high-calcium filled composite modified material, its preparation method and application, which ensures material performance, is compatible with existing mass production lines, and significantly reduces raw material costs.

[0007] To solve the above-mentioned technical problems, the technical solution provided by the present invention is as follows: a high-calcium filled composite modified material includes a matrix resin, a filler, an elastomer, an interface modifier, and an additive; The elastomer is a compound of EPDM rubber and POE polyolefin elastomer, and the interface modifier is a compound of titanate coupling agent and aluminate coupling agent. The proportions of the matrix resin, filler, elastomer, interface modifier, and additives by weight are 15-18:75-78:4-5:2.0-2.5:2.2-3.1.

[0008] Preferably, the matrix resin is homopolymer polypropylene; The filler is calcite powder, which passes through a 1250-mesh sieve and has a CaCO3 content of ≥99%. The additives include lubricating dispersants, anti-aging agents, and flow modifiers.

[0009] Preferably, the mass ratio of EPDM rubber to POE polyolefin elastomer in the elastomer is 1:1 to 2:1; The mass ratio of titanate coupling agent to aluminate coupling agent in the interface modifier is 1:1.

[0010] Preferably, the lubricating dispersant is a compound of zinc stearate, calcium stearate and polyethylene wax; The anti-aging agent is a mixture of antioxidant 1010 and antioxidant 168 in a mass ratio of 1:2. The flowability modifier is polypropylene wax.

[0011] Another aspect of the present invention discloses a method for producing a high-calcium filled composite modified material, comprising the following steps: S1: After grading and drying calcite powder, surface coating modification is carried out using an interface modification system to obtain modified calcite powder. S2: Homopolymer polypropylene and compounded elastomer are pulverized and dried; additives are premixed to form composite additive packages; S3: Add homopolymer polypropylene, compound elastomer, modified calcite powder, and composite additive package in sequence according to the formula ratio, wherein the modified calcite powder is added in 3 intervals. S4: The prepared materials are subjected to two-stage high-speed mixing to obtain a mixture with a uniformity of ≥99%; S5: The mixture is fed into a twin-screw extruder, and after segmented temperature-controlled extrusion and water ring cooling pelletizing, modified granules are obtained; S6: Modified granules are sieved and then vacuum-packed to obtain the finished product.

[0012] Preferably, in S2, the homopolymer polypropylene is pulverized to 3-5 mm, and the compounded elastomer is pulverized to 5-8 mm; The addition interval of the modified calcite powder in S3 is 3 minutes; In S4, the primary mixing speed is 800 r / min, the temperature is 65-70℃, and the time is 12 min; the secondary mixing speed is 1100 r / min, the temperature is 75-80℃, and the time is 8 min.

[0013] Preferably, the extrusion segment temperatures in S5 are: feeding section 140-150℃, plasticizing section one 175-185℃, plasticizing section two 190-200℃, dispersing section 195-205℃, extrusion section 200-210℃, and die head 195-205℃; The pellets in S5 have a diameter of 2-3 mm and a length of 2-3 mm, and the moisture content of the dried pellets is ≤0.1%.

[0014] Another aspect of the present invention discloses an application of the aforementioned high-calcium filled composite modified material.

[0015] Preferably, the applications include automotive interior parts, home appliance housings, and new energy components.

[0016] The advantages of this invention compared with the prior art are: this invention effectively solves the problems of filler agglomeration and poor interfacial compatibility, enabling the material to maintain good toughness, rigidity and processing fluidity, and its comprehensive performance meets the requirements of automobiles, home appliances and new energy components; In this invention, the synergistic effect of compound elastomer and compound coupling agent is used to balance toughening and dispersing effects, and the formula is stable and reliable. The preparation process in this invention is compatible with existing twin-screw extrusion production lines, requiring only minor technical modifications for mass production. The process is simple, the dispersion is uniform, the batch stability is high, the product qualification rate is excellent, and the product is recyclable and reusable, which is in line with the development direction of green materials. Attached Figure Description

[0017] Figure 1 This is the production process flow of the present invention. Figure 1 .

[0018] Figure 2 This is the production process flow of the present invention. Figure 2 .

[0019] Figure 3 This is a schematic diagram comparing the performance of embodiments of the present invention. Detailed Implementation

[0020] The present invention will now be described in further detail with reference to the accompanying drawings.

[0021] Combined with appendix Figure 1-2 As shown, the formulation of high-calcium filled PP / EPDM composite modified material is as follows: Matrix resin: 15-18 parts of homopolymer polypropylene, melt index of 18-20 g / 10 min (2.16 kg / 230 °C). Blended elastomer: 4-5 parts, composed of EPDM rubber (Mounney viscosity ML1+4 125℃ is 50-55) and polyolefin elastomer POE (melt index is 2-3g / 10min) in a ratio of 1:1 to 2:1; High-calcium filler: 75-78 parts calcite powder, particle size 1250 mesh, CaCO3 content ≥99%, whiteness ≥94%, moisture ≤0.3%; Interface modification system: 2.0-2.5 parts, composed of titanate coupling agent NDZ-105 and aluminate coupling agent DL-411 in a 1:1 ratio; Lubricating dispersion system: 1.5-2.0 parts, composed of zinc stearate, calcium stearate and polyethylene wax (molecular weight 3000-4000); Anti-aging system: 0.4-0.6 parts, composed of antioxidant 1010 and antioxidant 168 in a mass ratio of 1:2; Flowability modifier: 0.3-0.5 parts of polypropylene wax, melt index is 100-120g / 10min.

[0022] The composite material meets the following performance requirements: density ≤ 1.061 g / cm³, moisture content ≤ 0.1%, ash content ≤ 21%; tensile strength at break The strength of the material is ≥17MPa, the elongation at break is ≥30%, the yield flexural strength is ≥25MPa, the flexural modulus is ≥1650MPa, the notched impact strength of the cantilever beam is ≥42KJ / ㎡; the melt flow rate is ≥19g / 10min, and the injection molding temperature is 190-210℃.

[0023] The preparation method is as follows: S1: Raw material pretreatment: ① Calcite powder is graded and dried in a double-layer drum dryer (grade 1: 110-120℃ / 20min, grade 2: 130-140℃ / 15min), and cooled to below 40℃; after drying, it is put into a high-speed mixer, and a composite additive is added at 70-80℃ / 1000r / min and stirred for 10min, and zinc stearate and calcium stearate are added at 90-95℃ / 1200r / min and stirred for 15min to obtain modified calcite powder with a coating rate ≥98%. ② Homopolymer polypropylene is pulverized to 3-5mm, and EPDM and POE are mixed and pulverized to 5-8mm, and dried at 90℃ for 3h. ③ Antioxidant, polyethylene wax, and polypropylene wax are mixed to prepare a composite additive package; S2: Precise Batching: A fully automatic batching system with an accuracy of ±0.2% is used. Homopolymer polypropylene + compound elastomer, modified calcite powder (added in 3 batches, 3 minutes apart), and composite additive package are added in sequence according to the proportion. After batching, the calcite content deviation is ≤±0.5% by sampling test. S3: Staged mixing: The ingredients are fed into a two-stage high-speed mixer. The first stage is mixed at 800 r / min / 65-70℃ / 12 min, and the second stage is mixed at 1100 r / min / 75-80℃ / 8 min. The uniformity of the mixture is ≥99%. S4: Twin-screw extrusion granulation: Employs a twin-screw extruder with a screw diameter of 65mm and a length-to-diameter ratio of 44:1 (made of wear-resistant alloy, with an additional dispersing screw section). Section temperatures: Feed section 140-150℃, Plasticizing section 1175-185℃, Plasticizing section 2190-200℃, Dispersing section 195-205℃, Extrusion section 200-210℃, Die head 195-205℃; Screw speed 260-280r / min, Feeding speed 25-30r / min, Melt pressure 13-16MPa, Exhaust section vacuum degree -0.08~-0.09MPa; S5: Cooling pelletizing and segmented drying: Water ring cooling pelletizing (cooling water 25-30℃, water flow 1.2-1.5m / s, pelletizing 320-360r / min), particle size 2-3mm in diameter and 2-3mm in length; followed by segmented drying (first stage 85℃ / 1.5h, second stage 90℃ / 2-4h), the moisture content of the dried particles is ≤0.1%; S6: Screening and Packaging: The finished product is obtained by screening through a double-layer screen (10 mesh + 20 mesh) and vacuum moisture-proof packaging.

[0024] Example Components Schematic Table 1 Components Example 1 Example 2 Example 3 Homopolymer polypropylene (18-20 melt index) 16 15 18 EPDM (Mounney 50-55) 2.5 2 3 POE (2-3 melt index) 2.5 2 2 1250 mesh calcite powder 76 78 75 NDZ-105+DL-411(1:1) 2.2 2.5 2.0 Zinc stearate + calcium stearate + PE wax 1.8 2.0 1.5 Antioxidant 1010+168 (1:2) 0.5 0.6 0.4 PP wax (melt index 100-120) 0.4 0.5 0.3 All three sets of examples adopted the above preparation method, with only minor adjustments to key parameters such as extrusion and pelletizing based on the formula, and the final products all achieved the preset performance indicators.

[0025] The contents not described in detail in this specification are existing technologies known to those skilled in the art.

[0026] Even with 75-78% ultra-high calcium filler, the material still maintains excellent comprehensive performance. Its mechanical properties (tensile, impact, bending) and processing performance (melt flow rate) meet the requirements for use in automobiles, home appliances, and new energy components. Moreover, the performance deviation between batches is ≤±2%, which is far lower than the industry's conventional deviation (±5%). After 6 months of sealed storage, the performance degradation of the sample is ≤0.5%, demonstrating excellent storage stability.

[0027] With calcite powder accounting for over 75%, the amount of high-priced resins and elastomers is significantly reduced, and the cost per ton is 10%-15% lower than that of traditional modified PP. Raw material costs are controllable, making it suitable for cost-sensitive applications.

[0028] The manufacturing process is fully compatible with existing twin-screw extrusion production lines, requiring only minor targeted technical modifications (such as screw material and dispersion screw edges). The technical modification implementation cycle is 1-2 months, with a daily production capacity of ≥3 tons, enabling large-scale promotion and a product qualification rate of ≥99.5%.

[0029] The entire preparation process is free of VOC emissions, the product is recyclable and reusable, complies with the national green and low-carbon industry policy, and produces no secondary pollution.

[0030] The ratio of compound elastomers and coupling agents can be adjusted within the protection range according to actual application needs (toughness priority / fluidity priority) to adapt to the performance requirements of different scenarios.

[0031] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0032] The present invention and its embodiments have been described above. This description is not restrictive, and the accompanying drawings are only one embodiment of the present invention; the actual structure is not limited thereto. In conclusion, if those skilled in the art are inspired by this description and design similar structures and embodiments without departing from the spirit of the invention, such designs should fall within the protection scope of the present invention.

Claims

1. A high-calcium filled composite modified material, characterized in that: It includes matrix resin, fillers, elastomers, interface modifiers, and additives; The elastomer is a compound of EPDM rubber and POE polyolefin elastomer, and the interface modifier is a compound of titanate coupling agent and aluminate coupling agent. The proportions of the matrix resin, filler, elastomer, interface modifier, and additives by weight are 15-18:75-78:4-5:2.0-2.5:2.2-3.

1.

2. The high-calcium filled composite modified material according to claim 1, characterized in that: The matrix resin is homopolymer polypropylene; The filler is calcite powder, which passes through a 1250-mesh sieve and has a CaCO3 content of ≥99%. The additives include lubricating dispersants, anti-aging agents, and flow modifiers.

3. The high-calcium filled composite modified material according to claim 1, characterized in that: The mass ratio of EPDM rubber to POE polyolefin elastomer in the elastomer is 1:1-2:1; The mass ratio of titanate coupling agent to aluminate coupling agent in the interface modifier is 1:

1.

4. The high-calcium filled composite modified material according to claim 2, characterized in that: The lubricating dispersant is a compound of zinc stearate, calcium stearate and polyethylene wax; The anti-aging agent is a mixture of antioxidant 1010 and antioxidant 168 in a mass ratio of 1:

2. The flowability modifier is polypropylene wax.

5. A method for preparing the high-calcium filled composite modified material as described in any one of claims 1-4, characterized in that: Includes the following steps: S1: After grading and drying calcite powder, surface coating modification is carried out using an interface modification system to obtain modified calcite powder. S2: Homopolymer polypropylene and compounded elastomer are pulverized and dried; additives are premixed to form composite additive packages; S3: Add homopolymer polypropylene, compound elastomer, modified calcite powder, and composite additive package in sequence according to the formula ratio, wherein the modified calcite powder is added in 3 intervals. S4: The prepared materials are mixed in two stages at high speed to obtain a mixture with a uniformity of ≥99%; S5: The mixture is fed into a twin-screw extruder, and after segmented temperature-controlled extrusion and water ring cooling pelletizing, modified granules are obtained; S6: Modified granules are sieved and then vacuum-packed to obtain the finished product.

6. The high-calcium filled composite modified material according to claim 1, characterized in that: In S2, the homopolymer polypropylene is pulverized to 3-5 mm, and the compounded elastomer is pulverized to 5-8 mm. The addition interval of the modified calcite powder in S3 is 3 minutes; In S4, the primary mixing speed is 800 r / min, the temperature is 65-70℃, and the time is 12 min; the secondary mixing speed is 1100 r / min, the temperature is 75-80℃, and the time is 8 min.

7. The high-calcium filled composite modified material according to claim 1, characterized in that: The extrusion temperatures in S5 are as follows: feeding section 140-150℃, plasticizing section one 175-185℃, plasticizing section two 190-200℃, dispersing section 195-205℃, extrusion section 200-210℃, and die head 195-205℃. The pellets in S5 have a diameter of 2-3 mm and a length of 2-3 mm, and the moisture content of the dried pellets is ≤0.1%.

8. The application of a high-calcium filled composite modified material as described in any one of claims 1-4.

9. The application of the high-calcium filled composite modified material according to claim 8, characterized in that: The applications include automotive interior parts, home appliance housings, and new energy components.

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