Degradable plastic master batch and preparation and application thereof

Abstract

The application discloses a degradable plastic master batch as well as preparation and application thereof. The degradable plastic master batch comprises the following raw materials in parts by mass: 40-60 parts of polylactic acid, 30-50 parts of polybutylene adipate terephthalate, 10-20 parts of 9,9-di-n-octylfluorene copolymer, 3-9 parts of a degradation agent and 1-5 parts of a lubricant. The 9,9-di-n-octylfluorene copolymer is added into the plastic master batch with polylactic acid and polybutylene adipate terephthalate as a base body, so that the impact strength and tensile strength of the plastic master batch are effectively improved. In addition, the degradation agent can effectively degrade the 9,9-di-n-octylfluorene copolymer, and thus the plastic master batch with high impact strength and tensile strength and degradability is obtained.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of degradable plastics, and particularly relates to a degradable plastic master batch and preparation and application thereof. BACKGROUND

[0002] With the enhancement of people's environmental protection consciousness, degradable polymer materials are increasingly concerned by people. The degradable polymer materials mainly include polybutylene succinate (PBS), polybutylene adipate terephthalate (PBAT), polycaprolactone (PCL), carbon dioxide copolymer (PPC), polylactic acid (PLA), polyvinyl alcohol (PVA), polyhydroxyalkanoate (PHA), polyhydroxybutyrate (PHB), starch, chitosan, cellulose and chitin, etc. Among them, polylactic acid (PLA) and polybutylene adipate terephthalate (PBAT) are most widely used.

[0003] Polylactic acid (PLA) is strong in rigidity, but its ductility is insufficient; and polybutylene adipate terephthalate (PBAT) has good film forming performance, but its rigidity is low; blending polylactic acid and polybutylene adipate terephthalate can achieve good complementation in performance. However, the compatibility of polylactic acid and polybutylene adipate terephthalate is poor, which leads to low impact strength and tensile strength of the blend. Therefore, how to improve the impact strength and tensile strength of the degradable plastic master batch with polylactic acid and polybutylene adipate terephthalate as the base material is a problem to be solved. SUMMARY

[0004] In view of the deficiencies of the prior art, the application provides a degradable plastic master batch. By adding 9,9-di-n-octylfluorene copolymer in the plastic master batch with polylactic acid and polybutylene adipate terephthalate as the base material, the impact strength and tensile strength of the plastic master batch are effectively improved. In addition, the addition of the degrading agent can effectively degrade the 9,9-di-n-octylfluorene copolymer, and thus the plastic master batch with high impact strength and tensile strength and degradability is obtained.

[0005] The application aims to provide a degradable plastic master batch, which comprises the following raw materials in parts by mass: polylactic acid 40-60 parts, polybutylene adipate terephthalate 30-50 parts, 9,9-di-n-octylfluorene copolymer 10-20 parts, degrading agent 3-9 parts and lubricant 1-5 parts.

[0006] In some embodiments of the application, the weight average molecular weight of the polylactic acid is 60-180 thousand g / mol.

[0007] In some embodiments of the application, the weight average molecular weight of the polybutylene adipate terephthalate is 20-80 thousand g / mol.

[0008] In some embodiments of the present application, the 9,9-di-n-octylfluorene copolymer has the following structure:

[0009]

[0010] wherein the number average molecular weight Mn is 18.6-27.2 kDa, and the molecular weight distribution PDI is 1.9-3.0.

[0011] In some embodiments of the present application, the degrading agent is selected from nano-titanium dioxide and a co-degrading agent, and the co-degrading agent is selected from at least one of dendritic nano-zinc oxide and nano-hexagonal boron nitride.

[0012] In some embodiments of the present application, the mass ratio of the nano-titanium dioxide to the dendritic nano-zinc oxide is 0.8-1.2.

[0013] In some embodiments of the present application, the mass ratio of the nano-titanium dioxide to the dendritic nano-zinc oxide is 1:1.

[0014] In some embodiments of the present application, the mass ratio of the nano-titanium dioxide to the nano-hexagonal boron nitride is 0.8-1.2.

[0015] In some embodiments of the present application, the mass ratio of the nano-titanium dioxide to the nano-hexagonal boron nitride is 1:1.

[0016] In some embodiments of the present application, the mass ratio of the nano-titanium dioxide, the dendritic nano-zinc oxide and the nano-hexagonal boron nitride is 2-5:1-3:0.5-2.

[0017] In some embodiments of the present application, the particle size of the nano-titanium dioxide is 20-90 nm.

[0018] In some embodiments of the present application, the dendritic nano-zinc oxide is self-assembled from one-dimensional nanorods, and the diameter of the nanorods is 50-80 nm.

[0019] In some embodiments of the present application, the particle size of the nano-hexagonal boron nitride is 30-50 nm.

[0020] In some embodiments of the present application, the lubricant comprises at least one of stearic acid, oxidized polyethylene wax, paraffin wax, and glyceryl stearate.

[0021] Another object of the present application is to provide a preparation method of the degradable plastic master batch, comprising the following steps:

[0022] The polylactic acid, polybutylene adipate terephthalate, 9,9-di-n-octylfluorene copolymer, degrading agent and lubricant are mixed, extruded and granulated to obtain the degradable plastic master batch.

[0023] Another object of the present application is to provide the application of the degradable plastic master batch or the degradable plastic master batch prepared by the preparation method of the degradable plastic master batch in a film.

[0024] Another object of the present application is to provide a degradable film, wherein the degradable film is prepared by blowing the degradable plastic master batch.

[0025] Another object of the present application is to provide a preparation method of a degradable film, comprising the following steps:

[0026] The degradable plastic master batch is dried and blown to obtain the degradable film.

[0027] Compared with the prior art, the present application has the following beneficial effects:

[0028] (1) The 9,9-di-n-octylfluorene copolymer in the present application forms hydrogen bonds with polylactic acid and polybutylene adipate terephthalate, and further forms a crosslinked network. The side chain of the 9,9-di-n-octylfluorene copolymer is a long alkyl segment, which penetrates between the molecular chains of polylactic acid and polybutylene adipate terephthalate. In addition, there is a conjugation effect between the 9,9-di-n-octylfluorene copolymers. The conjugation effect further enhances the hydrogen bonding between the 9,9-di-n-octylfluorene copolymer and polylactic acid and polybutylene adipate terephthalate, and further promotes the formation of a crosslinked network, effectively improving the impact strength and tensile strength of the plastic master batch.

[0029] (2) The nano-titanium dioxide has a small particle size, a large specific surface area, and a high surface energy, and has a strong oxidation-reduction capacity. Under the action of ultraviolet light, the electrons (e - ) on the valence band of nano-titanium dioxide are easily excited to jump to the conduction band, generating corresponding holes (h + ) on the valence band. Subsequently, h + and e - react with water and oxygen molecules adsorbed on the surface of nano-titanium dioxide to generate OH - , O 2- , and OOH -Highly reactive free radicals with strong oxidizing properties can react with the C and H chains on the molecular chain of 9,9-di-n-octylfluorene copolymer, thereby degrading the 9,9-di-n-octylfluorene copolymer in the plastic masterbatch. However, the band gap of nano-titanium dioxide is 3.2 eV, so only ultraviolet light with a wavelength less than 387 nm can activate its oxidizing activity. This invention adds dendritic nano-zinc oxide and nano-hexagonal boron nitride to the plastic masterbatch. Dendritic nano-zinc oxide and nano-hexagonal boron nitride have high recombination efficiency of electron-hole pairs generated during light irradiation. Combining them with nano-titanium dioxide can improve the recombination efficiency of electron-hole pairs. This invention improves the oxidizing activity of titanium dioxide by combining nano-titanium dioxide, dendritic nano-zinc oxide, and nano-hexagonal boron nitride with special morphologies, thereby improving the degradability of the polymer in the plastic masterbatch.

[0030] (3) The carboxyl groups on the polylactic acid molecular chain, the hydroxyl groups on the polybutylene terephthalate-adipate molecular chain, and the hydroxyl groups on the surface of nano-titanium dioxide, dendritic nano-zinc oxide, and nano-hexagonal boron nitride have hydrogen bonding effects, which can improve the dispersibility of nano-titanium dioxide, dendritic nano-zinc oxide, and nano-hexagonal boron nitride, thereby improving the degradability of polymers in plastic masterbatches. Detailed Implementation

[0031] To enable those skilled in the art to better understand the technical solutions of this invention, the technical solutions in the embodiments of this invention will be clearly and completely described below in conjunction with the embodiments of this invention. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this invention.

[0032] All raw materials involved in this invention are commercially available.

[0033] Example 1

[0034] This embodiment provides a biodegradable plastic masterbatch, the preparation method of which includes the following steps:

[0035] 40 parts by weight of polylactic acid with a weight average molecular weight of 60,000 g / mol, 50 parts by weight of polybutylene terephthalate-adipate with a weight average molecular weight of 80,000 g / mol, 10 parts by weight of 9,9-di-n-octylfluorene copolymer, 5 parts by weight of nano-titanium dioxide with a particle size of 20-90 nm, 2 parts by weight of dendritic nano-zinc oxide composed of one-dimensional nanorods with a diameter of 50-80 nm, 2 parts by weight of nano-hexagonal boron nitride with a particle size of 30-50 nm, and 5 parts by weight of stearic acid were mixed, extruded and granulated to obtain biodegradable plastic masterbatch.

[0036] The structure of the 9,9-di-n-octylfluorene copolymer is shown below:

[0037]

[0038] The number-average molecular weight (Mn) is 23.1 kDa, and the molecular weight distribution index (PDI) is 2.4.

[0039] Example 2

[0040] This embodiment provides a biodegradable plastic masterbatch, the preparation method of which includes the following steps:

[0041] 60 parts by weight of polylactic acid with a weight average molecular weight of 180,000 g / mol, 30 parts by weight of polybutylene terephthalate-adipate with a weight average molecular weight of 20,000 g / mol, 20 parts by weight of 9,9-di-n-octylfluorene copolymer, 1 part by weight of nano-titanium dioxide with a particle size of 20-90 nm, 1.5 parts by weight of dendritic nano-zinc oxide with a diameter of 50-80 nm and self-assembled from one-dimensional nanorods, 0.5 parts by weight of nano-hexagonal boron nitride with a particle size of 30-50 nm, and 1 part by weight of stearic acid were mixed and extruded to obtain biodegradable plastic masterbatch.

[0042] The structure of the 9,9-di-n-octylfluorene copolymer is shown below:

[0043]

[0044] The number-average molecular weight (Mn) is 18.6 kDa, and the molecular weight distribution index (PDI) is 3.0.

[0045] Example 3

[0046] This embodiment provides a biodegradable plastic masterbatch, the preparation method of which includes the following steps:

[0047] 50 parts by weight of polylactic acid with a weight average molecular weight of 120,000 g / mol, 40 parts by weight of polybutylene terephthalate-adipate with a weight average molecular weight of 50,000 g / mol, 15 parts by weight of 9,9-di-n-octylfluorene copolymer, 3 parts by weight of nano-titanium dioxide with a particle size of 20-90 nm, 2.5 parts by weight of dendritic nano-zinc oxide with a diameter of 50-80 nm and self-assembled from one-dimensional nanorods, 0.5 parts by weight of nano-hexagonal boron nitride with a particle size of 30-50 nm, and 3 parts by weight of stearic acid were mixed, extruded and granulated to obtain biodegradable plastic masterbatch.

[0048] The structure of the 9,9-di-n-octylfluorene copolymer is shown below:

[0049]

[0050] The number-average molecular weight (Mn) is 27.2 kDa, and the molecular weight distribution index (PDI) is 1.9.

[0051] Example 4

[0052] This embodiment provides a biodegradable plastic masterbatch, the preparation method of which includes the following steps:

[0053] 50 parts by weight of polylactic acid with a weight average molecular weight of 120,000 g / mol, 40 parts by weight of polybutylene terephthalate-adipate with a weight average molecular weight of 50,000 g / mol, 15 parts by weight of 9,9-di-n-octylfluorene copolymer, 3 parts by weight of nano-titanium dioxide with a particle size of 20-90 nm, 3 parts by weight of dendritic nano-zinc oxide with a diameter of 50-80 nm and self-assembled from one-dimensional nanorods, and 3 parts by weight of stearic acid were mixed and extruded to granulate, thus obtaining a biodegradable plastic masterbatch.

[0054] The structure of the 9,9-di-n-octylfluorene copolymer is shown below:

[0055]

[0056] The number-average molecular weight (Mn) is 27.2 kDa, and the molecular weight distribution index (PDI) is 1.9.

[0057] Example 5

[0058] This embodiment provides a biodegradable plastic masterbatch, the preparation method of which includes the following steps:

[0059] 50 parts by weight of polylactic acid with a weight average molecular weight of 120,000 g / mol, 40 parts by weight of polybutylene terephthalate with a weight average molecular weight of 50,000 g / mol, 15 parts by weight of 9,9-di-n-octylfluorene copolymer, 3 parts by weight of nano-titanium dioxide with a particle size of 20-90 nm, 3 parts by weight of nano-hexagonal boron nitride with a particle size of 30-50 nm, and 3 parts by weight of stearic acid are mixed, extruded and granulated to obtain biodegradable plastic masterbatch;

[0060] The structure of the 9,9-di-n-octylfluorene copolymer is shown below:

[0061]

[0062] The number-average molecular weight (Mn) is 27.2 kDa, and the molecular weight distribution index (PDI) is 1.9.

[0063] Example 6

[0064] This embodiment provides a biodegradable plastic masterbatch, the preparation method of which includes the following steps:

[0065] 50 parts by weight of polylactic acid with a weight average molecular weight of 120,000 g / mol, 40 parts by weight of polybutylene terephthalate-adipate with a weight average molecular weight of 50,000 g / mol, 15 parts by weight of 9,9-di-n-octylfluorene copolymer, 6 parts by weight of nano-titanium dioxide with a particle size of 20-90 nm, and 3 parts by weight of stearic acid were mixed and extruded to granulate, thus obtaining biodegradable plastic masterbatch.

[0066] The structure of the 9,9-di-n-octylfluorene copolymer is shown below:

[0067]

[0068] The number-average molecular weight (Mn) is 27.2 kDa, and the molecular weight distribution index (PDI) is 1.9.

[0069] Comparative Example 1

[0070] This comparative example provides a biodegradable plastic masterbatch, the preparation method of which includes the following steps:

[0071] 55 parts by weight of polylactic acid with a weight average molecular weight of 120,000 g / mol, 50 parts by weight of polybutylene terephthalate-adipate with a weight average molecular weight of 50,000 g / mol, 3 parts by weight of nano-titanium dioxide with a particle size of 20-90 nm, 2.5 parts by weight of dendritic nano-zinc oxide with a diameter of 50-80 nm and self-assembled from one-dimensional nanorods, 0.5 parts by weight of nano-hexagonal boron nitride with a particle size of 30-50 nm, and 3 parts by weight of stearic acid were mixed and extruded to obtain a biodegradable plastic masterbatch.

[0072] Performance testing:

[0073] Tensile strength: After preparing dumbbell-shaped specimens of type 1A according to standard GB / T 1040.2-2022 "Determination of tensile properties of plastics - Part 2: Test conditions for molded and extruded plastics", the tensile strength test was carried out according to standard GB / T 1040.1-2018 "Determination of tensile properties of plastics - Part 1: General rules" at a test speed of 1 mm / min.

[0074] Impact strength: The notched impact strength of the cantilever beam was tested according to the standard GB / T 1843-2008 "Determination of impact strength of plastic cantilever beam". The sample size (length × width × thickness) was 80mm × 10mm × 4mm, and the notch type was A.

[0075] Degradation performance: The biodegradable plastic masterbatches of Examples 1-6 and Comparative Example 1 were dried and blow-molded to obtain biodegradable films. The biodegradable film samples were tested for 12-week disintegration rate and 60-day biodegradation rate under industrial composting light conditions, in accordance with the standard GB / T 41010-2021 "Degradation performance and labeling requirements of biodegradable plastics and products".

[0076] Table 1. Performance test results of biodegradable plastic masterbatches in Examples 1-6 or Comparative Example 1.

[0077] Sample Tensile strength (MPa) Izod notched impact strength (KJ / m 2 ) Disintegration rate (%) Biodegradation rate (%) Example 1 67.2 25.3 81.4 75.4 Example 2 65.9 23.7 78.7 72.2 Example 3 69.5 22.0 76.8 70.9 Example 4 63.7 24.5 60.5 56.6 Example 5 62.4 23.1 59.2 53.1 Example 6 64.8 21.9 43.6 37.5 Comparative Example 1 45.1 13.2 87.3 80.7

[0078] As shown in Table 1, the biodegradable plastic masterbatches prepared in Examples 1-6 of this invention have high tensile strength and cantilever beam notched impact strength, and also have good degradation performance.

[0079] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that after reading this application specification, they can still modify or make equivalent substitutions to the specific implementation of the present invention, but these modifications or changes do not depart from the protection scope of the pending claims of the present invention.

Claims

1. A biodegradable plastic masterbatch, characterized in that, The raw materials include the following parts by weight: 40-60 parts of polylactic acid, 30-50 parts of polybutylene terephthalate-adipate, 10-20 parts of 9,9-di-n-octylfluorene copolymer, 3-9 parts of degradation agent, and 1-5 parts of lubricant; The structure of the 9,9-di-n-octylfluorene copolymer is shown below: The number-average molecular weight (Mn) ranges from 18.6 to 27.2 kDa, and the molecular weight distribution (PDI) ranges from 1.9 to 3.

0.

2. The biodegradable plastic masterbatch as described in claim 1, characterized in that, The weight-average molecular weight of the polylactic acid is 60,000 to 180,000 g / mol; And / or, the weight-average molecular weight of the polybutylene terephthalate is 20,000 to 80,000 g / mol.

3. The biodegradable plastic masterbatch as described in claim 1, characterized in that, The degradation agent is selected from nano-titanium dioxide and degradation aid, and the degradation aid is selected from at least one of dendritic nano-zinc oxide and nano-hexagonal boron nitride.

4. The biodegradable plastic masterbatch as described in claim 3, characterized in that, The mass ratio of nano-titanium dioxide to dendritic nano-zinc oxide is 0.8~1.2; The mass ratio of nano-titanium dioxide to nano-hexagonal boron nitride is 0.8~1.2; The mass ratio of the nano-titanium dioxide, dendritic nano-zinc oxide, and nano-hexagonal boron nitride is 2~5:1~3:0.5~2.

5. The biodegradable plastic masterbatch as described in claim 3, characterized in that, The particle size of the nano-titanium dioxide is 20~90nm.

6. The biodegradable plastic masterbatch as described in claim 3, characterized in that, The dendritic zinc oxide nanoparticles are self-assembled from one-dimensional nanorods with a diameter of 50-80 nm.

7. The biodegradable plastic masterbatch as described in claim 3, characterized in that, The particle size of the nano-hexagonal boron nitride is 30~50nm.

8. The biodegradable plastic masterbatch as described in claim 1, characterized in that, The lubricant includes at least one of stearic acid, oxidized polyethylene wax, paraffin, and glyceryl stearate.

9. The method for preparing the biodegradable plastic masterbatch according to any one of claims 1 to 8, characterized in that, Includes the following steps: Polylactic acid, polybutylene terephthalate, 9,9-di-n-octylfluorene copolymer, degrading agent and lubricant are mixed and extruded to granulate, thus obtaining biodegradable plastic masterbatch.

10. The application of the biodegradable plastic masterbatch according to any one of claims 1 to 8 or the biodegradable plastic masterbatch according to claim 9 prepared by the preparation method in films.

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