Preparation method of reactive nanoparticle compatibilizer and polylactic acid blend
By combining titanium dioxide with silane coupling agent and introducing a polymethyl methacrylate compatibilizer system, the problem of phase separation in polymer blending is solved, and the effect of enhancing compatibility and performance is achieved.
Patent Information
- Application Number
- CN202510253044.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-05
- Publication Date
- 2025-06-24
AI Technical Summary
In the field of polymer materials, phase separation is often caused by thermodynamic incompatibility during polymer blending, resulting in a decline in the mechanical properties of the materials, limiting its application in high-end fields.
Titanium dioxide is introduced into a compatibilizer system with polymethyl methacrylate as a matrix through a silane coupling agent to improve the compatibility of titanium dioxide with polymers and impart the compatibilizers against UV and antibacterial properties.
It significantly improves the reactive activity and capacity enhancement properties of the compatibilizer, enhances the compatibility and adhesion of the polymer blend system, and enhances the mechanical properties and application range of the material.
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Figure CN120192540A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of polymer materials, and particularly relates to a preparation method of a reactive nanoparticle compatibilizer and a polylactic acid blend. Background Art
[0002] In the field of polymer materials, polymer blending technology, as a key means for developing multifunctional composite materials, can optimize properties through the synergistic effect of different polymers to meet the requirements of diverse application scenarios. However, the core challenge of this technology is that the vast majority of polymer systems exhibit thermodynamic incompatibility, resulting in easy macroscopic phase separation during the blending process, forming a significant "sea-island" structure. This microscopic phase separation not only causes interfacial stress concentration, leading to a sharp decline in the mechanical properties of the material, but also results in coarsening of the phase regions and deterioration of properties during long-term use, severely restricting the application of blended materials in high-end fields.
[0003] Compatibilizers can improve the disadvantage of poor compatibility of most polymers during blending, reduce the interfacial tension, and enable various polymers to be fully plasticized under the action of the compatibilizer through processing techniques such as granulation and injection molding to form new materials with high strength. Therefore, usually, compatibilizers are used to improve problems such as layering and surface peeling during the processing of polymers such as injection molding and extrusion, which cause defects such as low material strength and brittleness.
[0004] Currently, the common compatibilizers mainly include maleic anhydride grafted compatibilizers, which are divided into non-reactive compatibilizers and reactive compatibilizers. Maleic anhydride grafted non-reactive compatibilizers are mostly single polymers. Reactive compatibilizers, such as PP grafted maleic anhydride, have low reactivity and a narrow application range. And compatibilizers with suitable properties are crucial for the blending effect of polymers. Summary of the Invention
[0005] The object of the present invention is to address the above technical problems and provide a preparation method of a reactive nanoparticle compatibilizer. By using a silane coupling agent, titanium dioxide (TiO2) is introduced into a compatibilizer system based on polymethyl methacrylate (PMMA), while endowing the compatibilizer with excellent compatibilizing properties, anti-ultraviolet, and antibacterial properties.
[0006] The preparation method of the reactive nanoparticle compatibilizer in the technical solution of the present invention includes the following steps: (1) In the dispersion liquid of titanium dioxide, a silane coupling agent is added for surface grafting to obtain titanium dioxide containing the silane coupling agent, denoted as siloxy titanium dioxide; (2) In the dispersion liquid of siloxy titanium dioxide, polymethyl methacrylate and a catalyst are added for a condensation reaction, and after cooling, filtration, washing, and drying are carried out; the reaction process is shown in formula (1): Formula (1).
[0007] By modifying titanium dioxide with a silane coupling agent and then introducing the titanium dioxide into a compatibilizer system based on polymethyl methacrylate, the compatibility between titanium dioxide and the polymer can be effectively enhanced, obtaining a compatibilizer with good compatibilizing effect and capable of combining well with other polymers, enabling it to play a good role during polymer blending.
[0008] Furthermore, in step (1), the dispersion of titanium dioxide is obtained by dispersing nano-titanium dioxide in a solvent at a concentration of 0.01 - 0.05 g / mL.
[0009] Preferably, the particle size of titanium dioxide is 30 - 100 nm.
[0010] Furthermore, in step (1), the molecular structure of the silane coupling agent has an epoxy group.
[0011] The epoxy group in the silane coupling agent can significantly improve the reaction activity of the compatibilizer, enabling it to graft different types of polymer long chains, thereby broadening its application scope in various incompatible systems.
[0012] Furthermore, in step (1), the mass ratio of the silane coupling agent to titanium dioxide is 2 - 5:1.
[0013] Preferably, in step (1), the surface grafting is carried out under an inert atmosphere, and the inert atmosphere is a nitrogen atmosphere or an argon atmosphere.
[0014] Furthermore, in step (1), the temperature of the surface grafting is 100 - 150 °C, and the time is 5 - 20 h.
[0015] Preferably, after the obtained silicon-oxy titanium dioxide in step (1) is filtered, it is washed 3 - 5 times with dichloromethane and then dried under vacuum at 60 - 150 °C for 4 - 10 h.
[0016] Preferably, in step (2), the dispersion of silicon-oxy titanium dioxide is obtained by dispersing silicon-oxy titanium dioxide in a solvent at a concentration of 0.01 - 0.05 g / mL.
[0017] Preferably, the solvent is any one of toluene, xylene, dimethyl sulfoxide, and phenol.
[0018] Furthermore, in step (2), the masses of polymethyl methacrylate and the catalyst are 0.5 - 1.5 times and 0.05 - 0.15 times the mass of silicon-oxy titanium dioxide, respectively.
[0019] Furthermore, in step (2), the tail section of the molecular structure of polymethyl methacrylate has a carboxyl group; it can react with the epoxy group on the surface of the modified titanium dioxide, thereby effectively connecting to the surface of titanium dioxide and enhancing the binding force with titanium dioxide.
[0020] Further, in step (2), the catalyst is any one of amine catalysts, imidazole catalysts, dicyandiamide catalysts, and hydrazide catalysts; including but not limited to any one of N,N-dimethylbenzylamine, triethylamine, tetraethylamine, 2-ethyl-4-methylimidazole, and phthalylhydrazide.
[0021] Further, in step (2), the temperature of the condensation reaction is 100~200 °C and the time is 20~30 h.
[0022] Preferably, after filtration, the product obtained in step (2) is washed 3~5 times with dichloromethane and then vacuum dried at 60~150 °C for 4~10 h.
[0023] The present invention also provides a reactive nanoparticle compatibilizer prepared by the above-mentioned preparation method of the reactive nanoparticle compatibilizer.
[0024] The present invention also provides a polylactic acid blend, comprising the following raw materials in parts by weight: 20~50 parts of poly-L-lactic acid, 20~50 parts of polyvinylidene fluoride, and 0.2~1.5 parts of the above-mentioned reactive nanoparticle compatibilizer.
[0025] The obtained reactive nanoparticle compatibilizer is added to the blend system of poly-L-lactic acid and polyvinylidene fluoride of and can be enriched at the interface between the two to reduce the interfacial tension, improve the adhesion between the two blends, and in-situ react at the interface to generate graft or block copolymers at the interface, thereby improving the blending effect.
[0026] Further, the above-mentioned polylactic acid blend is obtained by premixing poly-L-lactic acid, polyvinylidene fluoride, and the reactive nanoparticle compatibilizer and then melt-blending in a Haake mixer.
[0027] Further, the temperature of the melt-blending is 150~250 °C, the rotation speed is 30~100 rpm, and the time is 5~20 min.
[0028] Compared with the prior art, the technical solution of the present invention has the following beneficial effects: (1) Through the silane coupling agent, titanium dioxide is introduced into the compatibilizer system based on polymethyl methacrylate, and at the same time, the compatibilizer is endowed with excellent compatibilizing performance, ultraviolet resistance, and antibacterial properties; (2) By modifying titanium dioxide with a silane coupling agent, the compatibility between titanium dioxide and the polymer can be effectively enhanced, and a compatibilizer with good compatibilizing effect and good binding ability with other polymers can be obtained, enabling it to play a good role during polymer blending; (3) The nano-titanium dioxide particles can endow the compatibilizer with properties such as ultraviolet resistance and antibacterial properties, expanding the application range of the compatibilizer; (4) The epoxy groups in the silane coupling agent can significantly improve the reaction activity of the compatibilizer, enabling it to graft different types of polymer long chains, thereby broadening its application scope in various incompatible systems; (5) The carboxyl group at the end segment in the molecular structure of polymethyl methacrylate can react with the hydroxyl groups on the surface of titanium dioxide, thus effectively connecting to the surface of titanium dioxide; (6) The resulting reactive nanoparticle compatibilizer in the blend system can accumulate at the interface to reduce the interfacial tension, improve the adhesion between the two blend phases, and through the reaction at the interface, in-situ react to generate graft or block copolymers, enhancing the blending effect. Description of the Drawings
[0029] Figure 1 It is the SEM picture of the cross-section of the polylactic acid blend obtained in Application Example 1; Figure 2 It is the SEM picture of the cross-section of the polylactic acid blend obtained in Application Example 2; Figure 3 It is the schematic diagram of the reactive nanoparticle compatibilizer acting in the polylactic acid blend in the present invention; Figure 4 It is the SEM picture of the cross-section of the polylactic acid blend obtained in Application Comparative Example 1; Figure 5 It is the schematic diagram of TiO2 acting in the polylactic acid blend in Application Comparative Example 1; Figure 6 It is the SEM picture of the cross-section of the polylactic acid blend obtained in Application Comparative Example 4. Specific Embodiments
[0030] The technical solutions of the present invention will be further described and illustrated below through specific embodiments and drawings. It should be understood that the specific embodiments described herein are only used to help understand the present invention and are not used for specific limitations of the present invention. And the drawings used herein are only for better explaining the content disclosed by the present invention and do not have a limiting effect on the protection scope. If there is no special description, the raw materials used in the embodiments of the present invention are all commonly used raw materials in the art, and the methods used in the embodiments are all conventional methods in the art.
[0031] In the following examples and comparative examples, polymethyl methacrylate with a carboxyl group at the end of the molecular structure was used. The preparation method refers to "Synthesis of Reactive Comb Polymers and Their Applications as a Highly Efficient Compatibilizer in Immiscible Polymer Blends, Ind. Eng. Chem. Res. 2015, 54, 2081 - 2089". Specifically, 0.2 mol of methyl methacrylate, 0.002 mol of 4,4'-azobis(4-cyanovaleric acid), and 0.01 mol of mercaptoacetic acid were dissolved in 20 mL of tetrahydrofuran, and the reaction was carried out in a sealed manner at 60 °C for 4 h under a nitrogen atmosphere. The reaction was terminated with acetone, and the product was precipitated once in water and twice in petroleum ether, and the obtained product was dried in vacuo at 50 °C for 10 h. Example 1
[0032] The preparation method of the reactive nanoparticle compatibilizer in this example includes the following steps: (1) 3 g of TiO2 was dispersed in 300 mL of toluene and ultrasonically mixed. 9 mL of silane coupling agent KH560 was added dropwise, and the reaction was carried out at 110 °C for 10 h under a nitrogen atmosphere to obtain titanium dioxide containing the silane coupling agent, denoted as siloxy titanium dioxide. After filtration, it was washed three times with dichloromethane and then dried in vacuo at 80 °C for 4 h; (2) 3 g of siloxy titanium dioxide was dispersed in 300 mL of xylene and ultrasonically mixed. Then 3 g of PMMA and 0.3 g of N,N-dimethylbenzylamine were added, and the reaction was carried out at 140 °C for 24 h. After cooling, it was filtered, washed three times with dichloromethane, and dried in vacuo at 80 °C for 4 h. Example 2
[0033] The preparation method of the reactive nanoparticle compatibilizer in this example includes the following steps: (1) 3 g of TiO2 was dispersed in 300 mL of toluene and ultrasonically mixed. 12 mL of silane coupling agent YDH-701 was added dropwise, and the reaction was carried out at 120 °C for 15 h under a nitrogen atmosphere to obtain titanium dioxide containing the silane coupling agent, denoted as siloxy titanium dioxide. After filtration, it was washed three times with dichloromethane and then dried in vacuo at 80 °C for 4 h; (2) 3 g of siloxy titanium dioxide was dispersed in 270 mL of xylene and ultrasonically mixed. Then 2 g of PMMA and 0.4 g of N,N-dimethylbenzylamine were added, and the reaction was carried out at 160 °C for 28 h. After cooling, it was filtered, washed three times with dichloromethane, and dried in vacuo at 80 °C for 4 h. Example 3
[0034] The preparation method of the reactive nanoparticle compatibilizer in this example includes the following steps: (1) Disperse 3 g of TiO2 in 270 mL of toluene and mix ultrasonically. Dropwise add 14 mL of silane coupling agent KH560 and react at 130 °C for 12 h under a nitrogen atmosphere to obtain titanium dioxide containing the silane coupling agent, denoted as siloxy titanium dioxide. After filtration, wash it three times with dichloromethane and then vacuum dry at 80 °C for 4 h; (2) Disperse 3 g of siloxy titanium dioxide in 240 mL of xylene and mix ultrasonically. Then add 4 g of PMMA and 0.36 g of N,N-dimethylbenzylamine and react at 180 °C for 26 h. After cooling, filter, wash it three times with dichloromethane, and vacuum dry at 80 °C for 4 h. Example 4
[0035] The difference between this example and Example 1 is only that in step (1), 3 g of TiO2 is dispersed in 300 mL of toluene and mixed ultrasonically. Dropwise add 3 mL of silane coupling agent KH560 and react at 110 °C for 10 h under a nitrogen atmosphere to obtain titanium dioxide containing the silane coupling agent, denoted as siloxy titanium dioxide. After filtration, wash it three times with dichloromethane and then vacuum dry at 80 °C for 4 h. Example 5
[0036] The difference between this example and Example 1 is only that in step (1), 3 g of TiO2 is dispersed in 300 mL of toluene and mixed ultrasonically. Dropwise add 18 mL of silane coupling agent KH560 and react at 110 °C for 10 h under a nitrogen atmosphere to obtain titanium dioxide containing the silane coupling agent, denoted as siloxy titanium dioxide. After filtration, wash it three times with dichloromethane and then vacuum dry at 80 °C for 4 h. Example 6
[0037] The difference between this example and Example 1 is only that in step (1), 3 g of TiO2 is dispersed in 300 mL of toluene and mixed ultrasonically. Dropwise add 9 mL of 2-allyltrimethylsilane and react at 110 °C for 10 h under a nitrogen atmosphere to obtain titanium dioxide containing the silane coupling agent, denoted as siloxy titanium dioxide. After filtration, wash it three times with dichloromethane and then vacuum dry at 80 °C for 4 h. Example 7
[0038] The difference between this example and Example 1 is only that in step (2), 6.5 g of siloxy titanium dioxide is dispersed in 300 mL of xylene and mixed ultrasonically. Then add 3 g of PMMA and 0.3 g of N,N-dimethylbenzylamine and react at 140 °C for 24 h. After cooling, filter, wash it three times with dichloromethane, and vacuum dry at 80 °C for 4 h. Example 8
[0039] The difference between this example and Example 1 is only that in step (2), 1.8 g of siloxy titanium dioxide is dispersed in 300 mL of xylene and ultrasonically mixed, then 3 g of PMMA and 0.3 g of N,N-dimethylbenzylamine are added, and the reaction is carried out at 140 °C for 24 h. After cooling, it is filtered, washed three times with dichloromethane, and vacuum dried at 80 °C for 4 h. Example 9
[0040] The difference between this example and Example 1 is only that in step (2), 3 g of siloxy titanium dioxide is dispersed in 300 mL of xylene and ultrasonically mixed, then 3 g of PMMA and 0.3 g of N,N-dimethylbenzylamine are added, and the reaction is carried out at 140 °C for 24 h. After cooling, it is filtered, washed three times with dichloromethane, and vacuum dried at 80 °C for 4 h; the PMMA used is PMMA without a carboxyl group at the end segment. Comparative Example 1
[0041] The preparation method of the reactive nanoparticle compatibilizer in this comparative example includes the following steps: 3 g of TiO2 is dispersed in 300 mL of xylene and ultrasonically mixed, then 3 g of PMMA and 0.3 g of N,N-dimethylbenzylamine are added, and the reaction is carried out at 140 °C for 24 h. After cooling, it is filtered, washed three times with dichloromethane, and vacuum dried at 80 °C for 4 h. Comparative Example 2
[0042] The preparation method of the reactive nanoparticle compatibilizer in this comparative example includes the following steps: 9 mL of silane coupling agent KH560 is dispersed in 300 mL of xylene and ultrasonically mixed, then 3 g of PMMA and 0.3 g of N,N-dimethylbenzylamine are added, and the reaction is carried out at 140 °C for 24 h. After cooling, it is filtered, washed three times with dichloromethane, and vacuum dried at 80 °C for 4 h. Application Example 1
[0043] The reactive nanoparticle compatibilizer obtained in the above example is applied to the blending of polylactic acid. The specific steps are to pre-mix 25 parts of poly(L-lactic acid) (PLLA), 25 parts of poly(vinylidene fluoride) (PVDF), and 0.5 part of the reactive nanoparticle compatibilizer obtained in Example 1, and then melt blend at 190 °C and 50 rpm in a Haake mixer for 10 min. Application Example 2
[0044] The reactive nanoparticle compatibilizer obtained in the above example is applied to the blending of polylactic acid. The specific steps are to pre-mix 30 parts of poly(L-lactic acid) (PLLA), 30 parts of poly(vinylidene fluoride) (PVDF), and 0.3 part of the reactive nanoparticle compatibilizer obtained in Example 2, and then melt blend at 200 °C and 60 rpm in a Haake mixer for 10 min. Application Example 3
[0045] The reactive nanoparticle compatibilizer obtained from the above examples was applied to the blending of polylactic acid. The specific steps were as follows: 35 parts of poly(L-lactic acid) (PLLA), 40 parts of poly(vinylidene fluoride) (PVDF), and 1.0 part of the reactive nanoparticle compatibilizer obtained from Example 3 were pre-mixed, and then melt-blended at 210 °C and 80 rpm for 10 min in a Haake mixer. Application of Examples 4 - 8
[0046] The reactive nanoparticle compatibilizer obtained from the above examples was applied to the blending of polylactic acid. The specific steps were as follows: 25 parts of poly(L-lactic acid) (PLLA), 25 parts of poly(vinylidene fluoride) (PVDF), and 0.5 part of the reactive nanoparticle compatibilizer obtained from any one of Examples 4 - 8 were pre-mixed, and then melt-blended at 190 °C and 50 rpm for 10 min in a Haake mixer. Application of Comparative Examples 1 - 2
[0047] The reactive nanoparticle compatibilizer obtained from the above comparative examples was applied to the blending of polylactic acid. The specific steps were as follows: 25 parts of poly(L-lactic acid) (PLLA), 25 parts of poly(vinylidene fluoride) (PVDF), and 0.5 part of the reactive nanoparticle compatibilizer obtained from any one of Comparative Examples 1 - 2 were pre-mixed, and then melt-blended at 190 °C and 50 rpm for 10 min in a Haake mixer. Application of Comparative Example 3
[0048] 25 parts of poly(L-lactic acid) (PLLA), 25 parts of poly(vinylidene fluoride) (PVDF), and 0.1 part of the reactive nanoparticle compatibilizer obtained from Example 1 were pre-mixed, and then melt-blended at 190 °C and 50 rpm for 10 min in a Haake mixer. Application of Comparative Example 4
[0049] 25 parts of poly(L-lactic acid) (PLLA), 25 parts of poly(vinylidene fluoride) (PVDF), and 1.6 parts of the reactive nanoparticle compatibilizer obtained from Example 1 were pre-mixed, and then melt-blended at 190 °C and 50 rpm for 10 min in a Haake mixer.
[0050] Performance tests were carried out on the polylactic acid blends obtained from the above application examples and application comparative examples. The test results are shown in Table 1.
[0051] Table 1 Performance data of polylactic acid blends 。
[0052] As Figure 1-2 shown, in Application Examples 1 - 2, PLLA and The interface of PVDF has good contact. Through the obtained reactive nanoparticle compatibilizer are connected ( Figure 3), a good blending effect is obtained, and the obtained polylactic acid blend exhibits excellent properties; in Example 4, less silane coupling agent is used to modify TiO2, and the binding force between TiO2 and the polymer is limited, resulting in a deteriorated compatibilization effect of the obtained compatibilizer and a decrease in the blend properties; in Example 5, more silane coupling agent is used to modify TiO2, and the content of TiO2 in the compatibilizer system with the same content decreases, and the additional anti-ultraviolet and antibacterial properties decrease; in Example 6, the molecular structure of the silane coupling agent used does not carry an epoxy group, the reaction activity of the compatibilizer decreases, the binding force with PLLA and PVDF decreases, the blending effect becomes poor, and the blend properties decrease; in Example 7, an excessive amount of siloxy titanium dioxide is added, causing the excess siloxy titanium dioxide to be free in the compatibilizer system, resulting in a waste to some extent and not bringing any beneficial effect to the compatibilization effect; in Example 8, a small amount of siloxy titanium dioxide is added, and the improvement effect on the blending effect of PLLA and PVDF decreases, and the blend properties decrease; in Example 9, the end segment of the PMMA used does not carry a carboxyl group, the binding effect with TiO2 decreases, the compatibilization effect of the obtained compatibilizer becomes poor, the blending effect becomes poor, and the blend properties decrease; in Comparative Example 1, the TiO2 used is not modified with a silane coupling agent, and TiO2 is dispersed in PLLA, as Figure 5 shown, it cannot act at the interface between PLLA and PMMA, and the compatibilization effect of the obtained compatibilizer is extremely poor, and the blend interface separates ( Figure 4 ), and the performance is greatly reduced; in Comparative Example 2, TiO2 is not used, and the compatibilization effect of the obtained compatibilizer becomes poor, and the blend properties decrease; in Applied Comparative Example 3, a small amount of reactive nanoparticle compatibilizer is used, and the compatibilization effect is poor, and the blend properties decrease; in Applied Comparative Example 4, an excessive amount of reactive nanoparticle compatibilizer is used, which is distributed in the blend system, and the interfacial force between PLLA and PMMA decreases ( Figure 6 ), thereby reducing the mechanical properties of the blend and affecting its processing performance.
[0053] Finally, it should be noted that the specific embodiments described herein are merely illustrative of the spirit of the present invention and not a limitation on the embodiments of the present invention. Those skilled in the art to which the present invention pertains can make various modifications or supplements to the described embodiments or use similar methods to replace them. It is not necessary and impossible to list all the embodiments here. And these obvious changes or variations derived from the essence of the present invention still fall within the protection scope of the present invention. Interpreting them as any additional limitation is contrary to the spirit of the present invention.
Claims
1. A method for preparing a reactive nanoparticle compatibilizer, characterized in that: The following steps are involved: (1) A silane coupling agent is added to a dispersion of titanium dioxide to graft the surface of the titanium dioxide containing the silane coupling agent, which is referred to as siloxy titanium dioxide; (2) Adding polymethyl methacrylate and a catalyst to a dispersion of silicic acid titanium dioxide to carry out a condensation reaction, and filtering, washing and drying after cooling.
2. The preparation method according to claim 1, characterized in that: The molecular structure of the silane coupling agent in step (1) contains epoxy groups.
3. The preparation method according to claim 1, characterized in that: In step (1), the mass ratio of the silane coupling agent to titanium dioxide is 2-5:
1.
4. The preparation method according to claim 1, characterized in that: In step (1), the surface grafting temperature is 100-150°C and the time is 5-20 hours.
5. The preparation method according to claim 1, characterized in that: In step (2), the mass of polymethyl methacrylate and the catalyst are 0.5 to 1.5 times and 0.05 to 0.15 times the mass of siloxy-titanium dioxide, respectively.
6. The preparation method according to claim 1 or 5, characterized in that: The molecular structure of polymethyl methacrylate in step (2) has a carboxyl group at the tail end.
7. The preparation method according to claim 1, characterized in that: The catalyst in step (2) is any one of an amine catalyst, an imidazole catalyst, a dicyandiamide catalyst, and a hydrazide catalyst.
8. The preparation method according to claim 1, characterized in that: The condensation reaction temperature in step (2) is 100-200°C and the reaction time is 20-30h.
9. A reactive nanoparticle compatibilizer, characterized in that: The method is prepared according to claim 1.
10. A polylactic acid blend, characterized in that: The invention comprises the following raw materials in parts by weight: 20-50 parts of poly-L-lactic acid, 20-50 parts of polyvinylidene fluoride, and 0.2-1.5 parts of the reactive nanoparticle compatibilizer according to claim 9.