A composite adjuvant composition, its preparation and use

Abstract

The present application relates to C08K, and more particularly, the present application relates to a composite auxiliary agent composition and its preparation method and application. The raw materials for preparing the composition include a dibasic carboxylic acid salt; the dibasic carboxylic acid salt is prepared from a dibasic carboxylic acid, a fatty acid salt and nano-silicon dioxide. The present application provides a composite auxiliary agent composition which can be used in polyolefin processing, provides better toughness and higher heat distortion temperature, balances the two, and by using the composition of the present application, a higher beta crystal conversion rate can be achieved, which can be up to 90% or more, and is suitable for a wider processing range. The preparation method of the composition provided by the present application is simple, can realize the enhancement of toughness while promoting the stability of strength, and even is beneficial to the appropriate increase of the strength of homopolypropylene. And the composition can also be used in random polypropylene, can reduce the strength decrease of random polypropylene, and obtain a nucleating agent suitable for random and homopolypropylene.

Description

Technical Field

[0001] This invention relates to C08K, and more specifically, to a composite additive composition, its preparation method, and its application. Background Technology

[0002] Polyolefins, such as polypropylene, are general-purpose materials and come in various types, including atactic, syndiotactic, and homopolymer. Different polyolefins have different properties, and their mechanical and thermal properties also differ. For example, atactic polypropylene has poor high-temperature resistance and pressure resistance, while homopolymer polypropylene has poor toughness.

[0003] Nucleating agents, as processing aids, can improve the mechanical and thermal properties of polyolefins by altering their crystallization properties. CN102226026B provides a composite β-crystal nucleating agent for polypropylene processing, comprising a nucleating agent and a synergist, to improve crystallization efficiency.

[0004] However, while current β-crystal nucleating agents improve toughness, they also negatively impact rigidity, such as tensile strength and flexural strength, and they are difficult to achieve good results for different types of polyolefins. Summary of the Invention

[0005] To address the aforementioned problems, the first aspect of this invention provides a composite additive composition, wherein the raw materials for preparing the composition include a dicarboxylic acid salt; the dicarboxylic acid salt is prepared from a dicarboxylic acid, a fatty acid salt, and nano-silica.

[0006] As a preferred embodiment of the present invention, the method for preparing the dicarboxylic acid salt includes:

[0007] Dicarboxylic acid, fatty acid salt and nano-oxide are heated to 40-60℃ and mixed for 20-40 min to obtain the dicarboxylic acid salt.

[0008] As a preferred embodiment of the present invention, the method for preparing the dicarboxylic acid salt includes:

[0009] After grinding the fatty acid salt and nano-oxide, the mixture is heated to 40–60°C, and a dicarboxylic acid is added. The mixture is then stirred for 20–40 minutes to obtain the dicarboxylic acid salt. The grinding pressure of the fatty acid salt and nano-oxide is 0.03–0.05 MPa, and the grinding time is 5–10 minutes.

[0010] Dicarboxylates, as β-nucleating agents for polyolefins, exhibit good crystal form selectivity. However, due to the relative instability of the β-crystal form, other crystal forms may appear in polyolefin products during processing and molding. To promote the β-crystal conversion rate of dicarboxylates, inorganic powder loading is generally used. For example, inorganic powder and calcium acetate are first used to form calcium carbonate on the powder surface at high temperature, followed by in-situ polymerization with dicarboxylate. However, this method requires high temperatures and has poor process stability. In this invention, fatty acid salts and nano-oxides are first mechanically ground to form reaction sites and adsorption sites before adding dicarboxylate for reaction. This reduces high-temperature energy consumption and simultaneously promotes the formation of dicarboxylate structures on the inorganic powder surface, while also increasing the reaction rate. This promotes the formation of dicarboxylate and the dicarboxylate / fatty acid salt-coated inorganic powder composite structures, thereby promoting the subsequent formation of the β-crystal form and improving the toughness of polyolefins.

[0011] As a preferred embodiment of the present invention, the molar ratio of the fatty acid salt to the dicarboxylic acid is 1:1.3 to 1.5, such as 1:1.3, 1:1.35, 1:1.4, 1:1.45, or 1:1.5, and the weight ratio of the dicarboxylic acid to nano-silica is 1:0.1 to 0.3, such as 1:0.1, 1:0.15, 1:0.2, 1:0.25, or 1:0.3.

[0012] As a preferred embodiment of the present invention, the fatty acid salt is selected from C12 to C18 fatty acid salts, including stearate, laurate, and palmitate, and is preferably one or more of calcium, magnesium, zinc, and sodium salts of fatty acids, more preferably calcium and sodium salts of fatty acids, with a weight ratio of 1:0.2 to 0.4.

[0013] As a preferred embodiment of the present invention, the nano-oxide is selected from one or more of nano-silica, nano-titanium dioxide, nano-alumina, and nano-magnesium oxide. For example, Nanjing Tianxing New Materials Co., Ltd.'s nano-silica TSP-H10 (specific surface area of ​​200 m²) is an example. 2 / g), TSP-F90 (specific surface area of ​​300m²) 2 Preferably, the specific surface area of ​​the nano-oxide is 200–300 m² / g. 2 / g.

[0014] As a preferred embodiment of the present invention, the number of carbon atoms in the dicarboxylic acid is 5 to 10, and examples include pimelic acid, azelaic acid, and glutaric acid.

[0015] However, the inventors also discovered that when grafting and adsorbing fatty acid salts using grinding, if the adsorption or grafting density is low and the oxide surface is exposed, nano-titanium dioxide will promote the formation of α crystals, while nano-silica will inhibit the formation of β crystals, both of which will affect the improvement of toughness. This invention controls the content of fatty acid salts and dicarboxylic acids, so that the structure of the fatty acid salts and the carboxylic acid form a certain coordination, while the dicarboxylic acid and the hydroxyl groups on the surface of the nano-oxides interact, promoting the carboxylic acid to further increase the coating density of the nano-oxides, forming a more uniform β-loaded structure, and promoting the formation of β crystals and the improvement of toughness in subsequent processing.

[0016] As a preferred embodiment of the present invention, the raw materials for preparing the composite additive composition further include a calcium-based carrier, such as calcium carbonate, calcined kaolin, and calcium-based montmorillonite. The calcium-based carrier has a mesh size of 3000-5000 mesh.

[0017] As a preferred embodiment of the present invention, the weight ratio of the calcium-based carrier to the dicarboxylate is 0.1 to 0.2:1.

[0018] Furthermore, the inventors have also discovered that when using the nucleating agent provided by this invention, as the amount of nucleating agent increases, while the toughness, such as impact strength and elongation at break, increases, the rigidity of homopolymer polypropylene, such as flexural modulus, tensile strength, and flexural strength, remains essentially unchanged, maintaining a balance between rigidity and toughness. However, when used in random copolymer polypropylene, its toughness increases while its rigidity decreases significantly. This invention, by selecting a calcium-based carrier and a dicarboxylate to work together, utilizes the shear slip between the layers of the calcium-based carrier, especially the lamellar calcium-based carrier, to facilitate ion exchange between the exposed interlamellar calcium ions and the sodium ions on the surface of the dicarboxylate. The alkaline calcium-based montmorillonite and the hard acidic silica load are compressed, promoting the complexation of calcium ions of carboxylate and montmorillonite, thereby promoting the formation of a double-layered loaded structure and regulating the complexation skeleton and polarity of the composition of this invention. The inventors have found that when used in random copolymer polypropylene, it can improve the reduction in rigidity, making the composition provided by this invention usable in different types of polypropylene.

[0019] As a preferred embodiment of the present invention, the fatty acid salt includes calcium stearate and sodium silicate.

[0020] A second aspect of this invention provides a method for preparing the composite additive composition as described above, comprising: grinding a dicarboxylate and a calcium-based carrier, sieving, and obtaining the composition. The shear mixing temperature is 30–40°C, and cooling is performed when the temperature exceeds 40°C. During shear mixing, the increased collisions and temperature of the materials may cause damage to the complex structure and organic chains; therefore, the shear temperature must be controlled.

[0021] In a preferred embodiment of the present invention, the grinding pressure of the dicarboxylate and the calcium-based carrier is 0.1–0.2 MPa, and the grinding time is 5–10 min. The sieve used for sieving has a mesh size of 8000 mesh.

[0022] Furthermore, the inventors discovered that during grinding under high grinding pressure, adsorption and desorption occur frequently, affecting the uniformity of dicarboxylate loading. However, this invention utilizes medium- and short-chain fatty acid salts, such as sodium fatty acid, which, during the process, can buffer the carrier through ion exchange and facilitate chelation exchange of carboxylic acids with the dicarboxylate, promoting the formation and uniformity of the bilayer loading structure, thereby further improving strength, toughness, and thermal stability.

[0023] A third aspect of the present invention provides an application of the composite additive composition as described above in the processing of polyolefins.

[0024] Compared with the prior art, the present invention has the following advantages:

[0025] (1) The present invention provides a composite additive composition that can be used in polyolefin processing to provide better toughness and higher heat distortion temperature, balancing the two. Furthermore, the composition of the present invention can achieve a higher β crystal conversion rate, up to 90% or more, and is suitable for a wider range of processing.

[0026] (2) The polyolefin products prepared have good long-term performance and stability, and the hydrostatic strength and slow crack growth resistance are significantly improved, while the low-temperature impact resistance is also improved.

[0027] (3) In addition, the composition preparation method provided by the present invention is simple, which can enhance toughness while promoting strength stability, and even facilitate the appropriate increase of strength of homopolymer polypropylene.

[0028] (4) The composition can also be used in atactic polypropylene, which can reduce the strength loss in atactic polypropylene and obtain a nucleating agent suitable for both atactic and homopolymer polypropylene.

[0029] (5) The present invention uses a dicarboxylate-supported structure and a carrier to form a composite supported structure that provides better toughness and plasticity compared to conventional nucleating agents. Detailed Implementation

[0030] Example

[0031] Example 1

[0032] This example provides a composite additive composition. The raw materials for preparing the composition include a dicarboxylate. The dicarboxylate is prepared from a dicarboxylic acid, a fatty acid salt, and nano-silica. The preparation method of the dicarboxylate includes: grinding the fatty acid salt and the nano-oxide TSP-H10, heating to 50°C, adding the dicarboxylic acid, and mixing for 40 min to obtain the dicarboxylate. The grinding pressure of the fatty acid salt and the nano-oxide is 0.05 MPa, and the grinding time is 10 min. The molar ratio of the fatty acid salt to the dicarboxylic acid is 1:1.3, and the weight ratio of the dicarboxylic acid to the nano-silica is 1:0.3. The fatty acid salt is calcium stearate and sodium laurate, with a weight ratio of 1:0.3. The dicarboxylic acid is pimelic acid. The raw materials for preparing the composite additive composition also include a calcium-based carrier, which is calcium-based montmorillonite with a mesh size of 5000 mesh. The weight ratio of the calcium-based carrier to the dicarboxylate is 0.2:1.

[0033] This example provides a method for preparing the composite additive composition as described above, comprising: grinding a dicarboxylate and a calcium-based carrier, sieving, and obtaining the composition. The shear mixing temperature is between 30 and 40°C, and cooling is performed when the temperature exceeds 40°C. The grinding pressure of the dicarboxylate and the calcium-based carrier is 0.16 MPa, and the grinding time is 8 min. The sieve mesh size is 8000 mesh.

[0034] Example 2

[0035] This example provides a composite additive composition. The raw materials for preparing the composition include a dicarboxylic acid salt. The dicarboxylic acid salt is prepared from a dicarboxylic acid, a fatty acid salt, and nano-silica. The preparation method of the dicarboxylic acid salt includes: grinding the fatty acid salt and the nano-oxide TSP-F90, heating to 60°C, adding the dicarboxylic acid, and mixing for 30 min to obtain the dicarboxylic acid salt. The grinding pressure of the fatty acid salt and the nano-oxide is 0.04 MPa, the grinding time is 10 min, the molar ratio of the fatty acid salt to the dicarboxylic acid is 1:1.5, the weight ratio of the dicarboxylic acid to the nano-silica is 1:0.2, the fatty acid salt is calcium stearate and sodium laurate, the weight ratio is 1:0.2, and the dicarboxylic acid is pimelic acid. The raw materials for preparing the composite additive composition also include a calcium-based carrier, the calcium-based carrier is calcium-based montmorillonite with a mesh size of 4000 mesh, and the weight ratio of the calcium-based carrier to the dicarboxylic acid salt is 0.2:1.

[0036] This example provides a method for preparing the composite additive composition as described above, comprising: grinding a dicarboxylate and a calcium-based carrier, sieving, and obtaining the composition. The shear mixing temperature is between 30 and 40°C, and cooling is performed when the temperature exceeds 40°C. The grinding pressure of the dicarboxylate and the calcium-based carrier is 0.2 MPa, and the grinding time is 10 min. The sieve mesh size is 8000 mesh.

[0037] Example 3

[0038] This example provides a composite additive composition, the raw materials for which the composition is prepared include a dicarboxylic acid salt; the dicarboxylic acid salt is prepared from a dicarboxylic acid, a fatty acid salt, and nano-silica, and the preparation method of the dicarboxylic acid salt includes: grinding the fatty acid salt and the nano-oxide TSP-H10, heating to 50°C, adding the dicarboxylic acid, mixing for 40 min, to obtain the dicarboxylic acid salt, wherein the grinding pressure of the fatty acid salt and the nano-oxide is 0.05 MPa, the grinding time is 10 min, the molar ratio of the fatty acid salt to the dicarboxylic acid is 1:1.3, the weight ratio of the dicarboxylic acid to the nano-silica is 1:0.3, the fatty acid salt is calcium stearate and sodium laurate, the weight ratio is 1:0.3, and the dicarboxylic acid is pimelic acid.

[0039] Example 4

[0040] This example provides a composite additive composition, the raw materials for which the composition is prepared include a dicarboxylic acid salt; the dicarboxylic acid salt is prepared from a dicarboxylic acid, a fatty acid salt, and nano-silica, and the preparation method of the dicarboxylic acid salt includes: grinding the fatty acid salt and the nano-oxide TSP-H10, heating to 50°C, adding the dicarboxylic acid, mixing for 40 min, to obtain the dicarboxylic acid salt, wherein the grinding pressure of the fatty acid salt and the nano-oxide is 0.05 MPa, the grinding time is 10 min, the molar ratio of the fatty acid salt to the dicarboxylic acid is 1:1, the weight ratio of the dicarboxylic acid to the nano-silica is 1:0.3, the fatty acid salt is calcium stearate and sodium laurate, the weight ratio is 1:0.3, and the dicarboxylic acid is pimelic acid.

[0041] Example 5

[0042] This example provides a composite additive composition. The raw materials for preparing the composition include a dicarboxylate. The dicarboxylate is prepared from a dicarboxylic acid, a fatty acid salt, and nano-silica. The preparation method of the dicarboxylate includes: grinding the fatty acid salt and the nano-oxide TSP-H10, heating to 50°C, adding the dicarboxylic acid, and mixing for 40 min to obtain the dicarboxylate. The grinding pressure of the fatty acid salt and the nano-oxide is 0.05 MPa, the grinding time is 10 min, the molar ratio of the fatty acid salt to the dicarboxylic acid is 1:1.3, the weight ratio of the dicarboxylic acid to the nano-silica is 1:0.3, the fatty acid salt is calcium stearate, and the dicarboxylic acid is pimelic acid. The raw materials for preparing the composite additive composition also include a calcium-based carrier, which is calcium-based montmorillonite with a mesh size of 5000 mesh. The weight ratio of the calcium-based carrier to the dicarboxylate is 0.2:1.

[0043] This example provides a method for preparing the composite additive composition as described above, comprising: grinding a dicarboxylate and a calcium-based carrier, sieving, and obtaining the composition. The shear mixing temperature is between 30 and 40°C, and cooling is performed when the temperature exceeds 40°C. The grinding pressure of the dicarboxylate and the calcium-based carrier is 0.16 MPa, and the grinding time is 8 min. The sieve mesh size is 8000 mesh.

[0044] Performance Evaluation

[0045] The compositions provided in the examples were added to PPH powder (Yanshan Petrochemical, 230℃, 2.16kg melt flow rate of 1.0g / 10min), PPR-1 powder (Yanshan Petrochemical, 230℃, 2.16kg melt flow rate of 0.5g / 10min), and PPR-2 powder (230℃, 2.16kg melt flow rate of 20g / 10min). The samples obtained by extrusion molding were used as the experimental group, and the samples without the added compositions were used as the blank group. The following experiments were conducted. The formulation of the samples was: polypropylene (PPH / PPR) balance, antioxidant 1010 0.2wt%, antioxidant THP-24 0.2wt%, and the composition. The samples were tested as follows, and the results of the PPH sample and the PPR-1 and PPR-2 samples are shown in Tables 1, 2, and 3, respectively.

[0046] Table 1

[0047]

[0048]

[0049] Table 2

[0050]

[0051] Table 3

[0052]

[0053] The test results show that the composition provided by the present invention can be used in the processing of polyolefins to obtain materials with higher β crystal form, improve temperature resistance and mechanical properties while maintaining good rigidity and tensile properties.

Claims

1. A complex adjuvant composition characterized in that, The preparation raw material of the composition comprises dicarboxylic acid salt and calcium-based montmorillonite; the dicarboxylic acid salt is prepared from dicarboxylic acid, fatty acid salt and nano-silicon dioxide; The fatty acid salt is selected from C12-C18 fatty acid salt; The fatty acid salt is calcium salt and sodium salt of fatty acid, and the weight ratio is 1:0.2-0.4; The preparation method of the composite additive composition comprises: grinding and sieving the dicarboxylic acid salt and calcium-based montmorillonite to obtain the composition.

2. The method of claim 1, wherein, The preparation method of the dicarboxylic acid salt comprises: The dicarboxylic acid, fatty acid salt and nano-oxide are heated to 40-60 DEG C and mixed for 20-40 min to obtain the dicarboxylic acid salt.

3. The method of claim 1, wherein, The molar ratio of the fatty acid salt and dicarboxylic acid is 1:1.3-1.

5.

4. The method of claim 1, wherein, The number of carbon atoms of the dicarboxylic acid is 5-10.

5. The method of claim 1, wherein, The mesh number of the calcium-based montmorillonite is 3000-5000 mesh.

6. Use of the complex adjuvant composition according to any one of claims 1 to 5, characterized in that, It is used in polyolefin processing.

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