Toughened modified polyglycolic acid composite material as well as preparation method and application thereof

Abstract

The invention discloses a toughened and modified polyglycolic acid composite material and a preparation method and application thereof, and relates to the field of high polymer materials, the toughened and modified polyglycolic acid composite material comprises the following blended components: polyglycolic acid, PBAT resin, a compatilizer and inorganic filler modified PBAT master batch; based on 100 parts by weight of polyglycolic acid, 2 to 65 parts by weight of PBAT resin; 0.5 to 3.5 parts by weight of a compatilizer; and 5-40 parts by weight of inorganic filler modified PBAT master batch. The inorganic filler modified PBAT master batch is added into the composite material, on one hand, agglomeration of inorganic particles can be prevented by using a master batch method, on the other hand, the inorganic particles in the master batch can improve the dispersion condition of the PBAT and increase the strength of the composite material, and the inorganic particles and the PBAT have a synergistic effect to promote and improve the toughness of the composite material.

Description

Technical Field

[0001] This invention relates to the field of polymer materials, and more specifically, to a toughened modified polyglycolic acid composite material, its preparation method, and its application. Background Technology

[0002] Polyglycolic acid (PGA) is a biodegradable plastic with very high strength and modulus. However, PGA suffers from high brittleness and a narrow processing window, which greatly limits its application range. Therefore, modifying PGA to improve its overall performance is one of the key research and application areas.

[0003] To address the brittleness of PGA, melt blending techniques are typically used to incorporate elastomers or toughening materials, such as polybutylene adipate / terephthalate (PBAT), polycaprolactone (PCL), polyethylene oxide (PEO), and polybutylene succinate (PBS), to toughen and modify PGA. However, these elastomers themselves have low strength, and the intermolecular forces between them and PGA are weak, resulting in poor compatibility. These issues mean that modifying PGA with elastomers or toughening materials can significantly reduce its strength, causing the PGA composite to lose its inherent strength advantage without improving its toughness. Therefore, ensuring that the strength of PGA itself is not significantly reduced during the preparation of PGA composites is a major challenge in the current research on preparing high-toughness PGA composites. Summary of the Invention

[0004] To address the problems existing in the prior art, this invention provides a toughened modified polyglycolic acid (PGA) composite material, its preparation method, and its application. This invention incorporates inorganic filler-modified PBAT masterbatch into the composite material. On one hand, the masterbatch method prevents the agglomeration of inorganic particles; on the other hand, the inorganic particles in the masterbatch improve the dispersion of PBAT, thereby increasing the strength of the composite material and synergistically enhancing its toughness.

[0005] One of the objectives of this invention is to provide a toughened modified polyglycolic acid composite material.

[0006] The toughened modified polyglycolic acid composite material of the present invention comprises the following blended components:

[0007] PBAT masterbatch modified with polyglycolic acid, PBAT resin, compatibilizer and inorganic filler;

[0008] Based on 100 parts by weight of polyglycolic acid:

[0009] 2-65 parts by weight of PBAT resin;

[0010] Compatibilizer 0.5-3.5 parts by weight;

[0011] 5-40 parts by weight of inorganic filler-modified PBAT masterbatch.

[0012] In a preferred embodiment of the present invention:

[0013] Based on 100 parts by weight of polyglycolic acid:

[0014] 5-60 parts by weight of PBAT resin; more preferably 10-60 parts by weight;

[0015] Compatibilizer 0.8-3.0 parts by weight;

[0016] 8-37.5 parts by weight of inorganic filler modified PBAT masterbatch.

[0017] In a preferred embodiment of the present invention:

[0018] The inorganic filler-modified PBAT masterbatch comprises a blend of PBAT resin and inorganic particulate powder; preferably,

[0019] The inorganic granular powder is talc; more preferably, the talc is in the form of lamellae; even more preferably, the length of the lamellae talc is 2-20 μm, preferably 5-15 μm, and / or the width is 2-20 μm, preferably 5-15 μm.

[0020] In a preferred embodiment of the present invention:

[0021] The mass ratio of PBAT resin to inorganic granular powder in the inorganic filler modified PBAT masterbatch is (1-20):1, preferably (1-4):1.

[0022] In a preferred embodiment of the present invention:

[0023] The compatibilizer is at least one of epoxy compatibilizers. Preferably, the epoxy equivalent of the epoxy compatibilizer is 260-280. More preferably, the epoxy compatibilizer is an ADR-type epoxy compatibilizer, such as BASF ADR4468 compatibilizer and ADR4368 compatibilizer.

[0024] In a preferred embodiment of the present invention:

[0025] The polyglycolic acid has a molecular weight of 300,000 to 1,000,000 and / or a melting temperature of 210 to 230°C; and / or

[0026] The PBAT resin is a commonly used resin in the art. The molecular weight of the PBAT resin is not particularly limited, and those skilled in the art can select it based on experience. Preferably, it is a PBAT resin with a molecular weight of about 65,000 g / mol.

[0027] In a preferred embodiment of the present invention:

[0028] The inorganic filler-modified PBAT masterbatch is prepared by melt blending components including PBAT resin and inorganic particulate powder.

[0029] A second objective of this invention is to provide a method for preparing toughened modified polyglycolic acid composite materials as described in one objective of this invention.

[0030] The preparation method of the toughened modified polyglycolic acid composite material of the present invention includes:

[0031] The polyglycolic acid composite material is prepared by melt blending the components, including the polyglycolic acid, PBAT resin, compatibilizer and inorganic filler modified PBAT masterbatch, in the amounts specified above.

[0032] Preferably, the method includes:

[0033] (1) After the components including PBAT resin and inorganic filler are mixed evenly, inorganic filler modified PBAT masterbatch is obtained by melt blending.

[0034] (2) The dried polyglycolic acid, PBAT resin, compatibilizer, and inorganic filler modified PBAT masterbatch are mixed evenly in proportion and the polyglycolic acid composite material is obtained by melt blending.

[0035] In a preferred embodiment of the present invention:

[0036] In step (1):

[0037] The extruder heating zone used for melt blending comprises four sections from feeding to extrusion, preferably...

[0038] The temperature of the first heating zone of the extruder is 100–130°C, and / or the temperature of the second heating zone is 140–160°C, and / or the temperature of the third heating zone is 170–190°C, and / or the die temperature is 180–200°C; and / or,

[0039] The screw speed of the extruder is 10–60 rpm; and / or,

[0040] The blending time is 3–12 min;

[0041] And / or,

[0042] In step (2):

[0043] The extruder heating zone used for melt blending comprises four sections from feeding to extrusion, preferably...

[0044] The temperature of heating zone one of the extruder is 180–200°C, and / or the temperature of heating zone two is 205–220°C, and / or the temperature of heating zone three is 220–240°C, and / or the die temperature is 190–210°C; and / or,

[0045] The extruder screw speed is 10–60 rpm; and / or,

[0046] The blending time is 2 to 12 minutes, preferably 3 to 10 minutes.

[0047] In a preferred embodiment of the present invention:

[0048] In step (2):

[0049] The drying process employs vacuum drying. Preferably, the vacuum drying temperature is 30–80°C, and / or the vacuum degree is 10–80 kPa, and / or the time is 6–24 hours; and / or,

[0050] The polyglycolic acid composite material is obtained by cooling, granulation and drying after melt blending. Preferably, the drying is carried out by vacuum drying. More preferably, the vacuum drying temperature is 30-80℃ and / or the vacuum degree is 10-80KPa and / or the time is 6-24h.

[0051] A third objective of this invention is to provide a polyglycolic acid composite material sheet, wherein the sheet is prepared by vacuum pressing of the toughened modified polyglycolic acid composite material as described in one objective of this invention or the toughened modified polyglycolic acid composite material prepared by the preparation method described in another objective of this invention.

[0052] In a preferred embodiment of the present invention:

[0053] The vacuum pressing is performed using a vacuum film press. Preferably, the vacuum pressing temperature is 225-240℃, and / or the pressure is 1000-5000Kg, and / or the preheating time is 3-10min, and / or the hot pressing time is 1-3min.

[0054] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0055] This invention uses PBAT resin, a tough material, which can effectively improve the toughness of PGA. The compatibilizer has a good reaction effect on the hydroxyl and carboxyl groups on the PGA structure. By adjusting the interface between PGA and PBAT resin, it can react with the terminal hydroxyl and segmental carboxyl groups of PGA and PBAT molecules to generate reactants of PBAT and PGA, effectively increasing the interfacial compatibility between PGA and PBAT, and further improving the toughness of PGA-based composite materials.

[0056] This invention incorporates the aforementioned inorganic filler-modified PBAT masterbatch into the composite material. On one hand, the masterbatch method prevents the agglomeration of inorganic particles, ensuring uniform dispersion and fully leveraging their heterogeneous nucleation and reinforcing effects. On the other hand, the inorganic particles in the masterbatch improve the dispersion of PBAT resin, increasing the strength of the composite material without introducing additional components. This invention uses small-particle-size talc, resulting in more uniform dispersion. Furthermore, the small particle size, large specific surface area, and low content of talc ensure that it achieves its intended function without significantly impacting the biodegradability of the composite material. The addition of talc inhibits the proximity and fusion of PBAT resin particles, thereby reducing the phase size of the PBAT resin particles and fully leveraging the toughening effect of PBAT resin. Additionally, talc also promotes the dispersion of the compatibilizer, increasing the probability of reaction between the compatibilizer and PGA / PBAT resin. As a small-particle-size lamellar inorganic filler, talc has a large specific surface area, which allows it to nucleate and crystallize with PGA, thus providing strength support for the composite material. Furthermore, talc as an inorganic filler can also enhance the strength of the composite material. Therefore, using lamellar talc masterbatch can achieve uniform dispersion of talc without compromising the biodegradability of the composite material, improving the toughening effect of PBAT, and thereby achieving the strengthening and toughening of the PGA composite material.

[0057] The toughened modified PGA composite material of the present invention improves the toughness of PGA and enhances its overall performance by adding PBAT resin, compatibilizer, and inorganic filler to modify PBAT masterbatch in PGA, while maintaining the high tensile strength of PGA. Attached Figure Description

[0058] Figure 1 The image shows the scanning electron microscope (SEM) microstructure of the composite material prepared in Example 2.

[0059] Figure 2 The image shows the scanning electron microscope (SEM) microstructure of the composite material prepared in Comparative Example 2.

[0060] from Figure 1 , Figure 2The scanning electron microscope (SEM) microstructure images show that the addition of talc reduces the particle size of PBAT resin and makes the interface between PGA and PBAT resin more blurred. This is because the addition of talc results in a more uniform dispersion of PBAT resin and ADR4468 compatibilizer. Furthermore, talc inhibits the polymerization of PBAT resin, thus reducing its relative size and improving the interfacial bonding between PGA and PBAT resin. The reduced size of the PBAT resin helps to fully utilize its toughening effect. Additionally, the uniform dispersion of ADR4468 compatibilizer also improves the toughness and strength of the composite material. Therefore, the addition of talc is beneficial for improving the strength and toughness of the composite material. Detailed Implementation

[0061] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be noted that the following embodiments are only used to further illustrate the present invention and should not be construed as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the content of the present invention are still within the scope of protection of the present invention.

[0062] The raw materials used in the embodiments and comparative examples of this invention are all commercially available products, and the specific information is shown in Table 1 below:

[0063] Table 1

[0064] Serial Number name source Materials Information 1 PGA Shenzhen Boli PGA-5; Molecular weight: 500,000 2 PGA Shenzhen Boli PGA-6; Molecular weight: 1 million 3 PBAT resin BASF, Germany C1200 4 ADR compatibilizer BASF 4468 5 MDI compatibilizer Wanhua MDI-100 6 talcum powder Shanghai Wojiu Mineral Products Co., Ltd. -

[0065] Example 1

[0066] A toughened modified PGA composite material, comprising the following raw materials in parts by weight:

[0067] 100 parts by weight of PGA (molecular weight 500,000, melting temperature 220-230℃), 60 parts by weight of PBAT resin, 1.5 parts by weight of ADR4468 compatibilizer, and 15 parts by weight of talc-modified PBAT masterbatch. In the talc-modified PBAT masterbatch, the talc is in the form of lamellar sheets, approximately 5 μm in length and 5 μm in width, and the mass ratio of PBAT resin to talc is 1:1.

[0068] The preparation method of the above-mentioned toughened modified PGA composite material includes the following steps:

[0069] (1) After mixing PBAT resin and talc powder evenly at a mass ratio of 1:1, add it to an extruder for extrusion. The temperatures of heating zone 1, heating zone 2, heating zone 3 and die of the extruder are 130℃, 160℃, 170℃ and 180℃ respectively. The screw speed is 30rpm and the mixing time is 6min to make talc-modified PBAT masterbatch.

[0070] (2) 100 parts by weight of PGA, 60 parts by weight of PBAT resin, 1.5 parts by weight of ADR4468 compatibilizer, and 15 parts by weight of talc-modified PBAT masterbatch were vacuum dried separately at a temperature of 60°C, a vacuum degree of 80 kPa, and a time of 12 h. The vacuum-dried PGA, PBAT resin, ADR4468 compatibilizer, and talc-modified PBAT masterbatch were mixed evenly and extruded into an extruder. The temperatures of heating zone 1, heating zone 2, heating zone 3, and the die of the extruder were 180°C, 210°C, 230°C, and 210°C, respectively. The screw speed was 30 rpm, and the mixing time was 6 min. Then, the mixture was cooled, granulated, and dried at a temperature of 60°C, a vacuum degree of 80 kPa, and a drying time of 6 h to obtain the toughened modified PGA composite material.

[0071] Example 2

[0072] A toughened modified PGA composite material, whose composition and preparation method are basically the same as those in Example 1, except that it includes the following raw materials in parts by weight:

[0073] 100 parts by weight of PGA (molecular weight 500,000, melting temperature 220-230℃), 40 parts by weight of PBAT resin, 1.5 parts by weight of ADR4468 compatibilizer, and 15 parts by weight of talc-modified PBAT masterbatch. In the talc-modified PBAT masterbatch, the talc is in the form of lamellar sheets, approximately 5 μm in length and 5 μm in width, and the mass ratio of PBAT resin to talc is 1:1.

[0074] Example 3

[0075] A toughened modified PGA composite material, whose composition and preparation method are basically the same as those in Example 1, except that it includes the following raw materials in parts by weight:

[0076] The mixture comprises 100 parts by weight of PGA (molecular weight 500,000, melting temperature 220-230℃), 20 parts by weight of PBAT resin, 1.5 parts by weight of ADR4468 compatibilizer, and 15 parts by weight of talc-modified PBAT masterbatch. In the talc-modified PBAT masterbatch, the talc is in lamellar form, approximately 5 μm in length and 5 μm in width, and the mass ratio of PBAT resin to talc is 1:1.

[0077] Example 4

[0078] A toughened modified PGA composite material, whose composition and preparation method are basically the same as those in Example 1, except that it includes the following raw materials in parts by weight:

[0079] 100 parts by weight of PGA (molecular weight 500,000, melting temperature 220-230℃), 5 parts by weight of PBAT resin, 1.5 parts by weight of ADR4468 compatibilizer, and 15 parts by weight of talc-modified PBAT masterbatch. In the talc-modified PBAT masterbatch, the talc is in the form of lamellar sheets, approximately 5 μm in length and 5 μm in width, and the mass ratio of PBAT resin to talc is 1:1.

[0080] Comparative Example 1

[0081] A PGA material, the preparation method includes the following steps:

[0082] PGA (molecular weight 500,000, melt temperature 220-230℃) was vacuum dried at 60℃ and 80 kPa for 12 hours. The vacuum-dried PGA was then extruded into an extruder. The temperatures of heating zone 1, heating zone 2, heating zone 3, and the die were 180℃, 210℃, 230℃, and 210℃, respectively. The screw speed was 30 rpm, and the mixing time was 6 minutes. The material was then cooled, granulated, and dried at 60℃ and 80 kPa for 6 hours to obtain the PGA material.

[0083] The toughened modified PGA composites prepared in Examples 1-4 and the PGA material prepared in Comparative Example 1 were used to prepare sheets using a vacuum press. The vacuum press temperature was 230℃, the pressure was 2000 kg, the preheating time was 3 min, and the hot pressing time was 2 min. The prepared sheets were then used to prepare standard samples using a dumbbell-shaped cutter. The tensile strength of the standard samples was tested using a tensile testing machine according to ASTM D638-2014 standard, with a tensile rate of 1 mm / min. The test results are shown in Table 2 below.

[0084] Table 2

[0085] Group PGA to PBAT ratio Tensile strength (MPa) Elongation at break (%) Example 1 100:60 22.1±1.5 13.5±2.6 Example 2 100:40 37.5±1.9 13.3±0.8 Example 3 100:20 43±2.3 10.2±1.7 Example 4 100:5 57.5±1.1 5.7±0.6 Comparative Example 1 100:0 65±3.5 4.1±0.4

[0086] Table 2 shows the effect of different PGA to PBAT ratios on the mechanical properties of toughened modified PGA composites: The tensile strength of the toughened modified PGA composite sheet samples prepared in Examples 1-4 is lower than that of the PGA composite sheet sample prepared in Comparative Example 1, but the elongation at break is higher in all cases. Furthermore, in Examples 1-4, as the PABT resin content increases, the composite strength decreases, but the elongation at break increases from 5.7% to 13.5%. This is because PBAT resin has lower strength but better toughness; the addition of PBAT resin improves the toughness of the composite, but its lower strength also affects the overall strength. When the PGA to PBAT ratio is 100:40, the elongation at break of the composite is 13.3%, with minimal strength loss, achieving optimal mechanical properties and a relatively balanced material toughness and strength.

[0087] Example 5

[0088] A toughened modified PGA composite material, whose composition and preparation method are basically the same as those in Example 1, except that it includes the following raw materials in parts by weight:

[0089] 100 parts by weight of PGA (molecular weight 500,000, melting temperature 220-230℃), 40 parts by weight of PBAT resin, 0.8 parts by weight of ADR4468 compatibilizer, and 15 parts by weight of talc-modified PBAT masterbatch. In the talc-modified PBAT masterbatch, the talc is in the form of lamellar sheets, approximately 5 μm in length and 5 μm in width, and the mass ratio of PBAT resin to talc is 1:1.

[0090] Example 6

[0091] A toughened modified PGA composite material, whose composition and preparation method are basically the same as those in Example 1, except that it includes the following raw materials in parts by weight:

[0092] 100 parts by weight of PGA (molecular weight 500,000, melting temperature 220-230℃), 40 parts by weight of PBAT resin, 3.0 parts by weight of ADR4468 compatibilizer, and 15 parts by weight of talc-modified PBAT masterbatch. In the talc-modified PBAT masterbatch, the talc is in the form of lamellar sheets, approximately 5 μm in length and 5 μm in width, and the mass ratio of PBAT resin to talc is 1:1.

[0093] The toughened modified PGA composite materials prepared in Examples 5 and 6 were fabricated into sheets using a vacuum press. The vacuum press temperature was 230℃, the pressure was 2000 kg, the preheating time was 3 min, and the hot pressing time was 2 min. The resulting sheets were then cut into standard samples using a dumbbell-shaped cutter. The tensile strength of the standard samples was tested using a tensile testing machine according to ASTM D638-2014 standard, at a tensile rate of 1 mm / min. The test results are shown in Table 3 below.

[0094] Table 3

[0095] Group Compatibilizer content Tensile strength (MPa) Elongation at break (%) Example 2 1.5 parts by weight 37.5±1.9 13.3±0.8 Example 5 0.8 parts by weight 24.3±2.4 9.3±1.7 Example 6 3.0 parts by weight 32.1±3.1 9.5±2.3

[0096] Table 3 shows the effect of different compatibilizer contents on the mechanical properties of toughened modified PGA composites: When the compatibilizer content is low, both the strength and elongation at break of the composite decrease. This is because the compatibilizer reacts with the end groups of PGA and PBAT resins, thereby increasing the compatibility between PGA and PBAT resins. A decrease in compatibilizer content leads to a decrease in the compatibility between PGA and PBAT, affecting strength and toughness. However, compatibilizers are small molecules; excessively high contents can prevent a large amount of compatibilizer from participating in the reaction, thus affecting the strength and toughness of the composite. When the compatibilizer content is 1.5 parts by weight, the composite exhibits relatively good toughness and strength.

[0097] Example 7

[0098] A toughened modified PGA composite material, whose composition and preparation method are basically the same as those in Example 1, except that it includes the following raw materials in parts by weight:

[0099] 100 parts by weight of PGA (molecular weight 500,000, melting temperature 220-230℃), 40 parts by weight of PBAT resin, 1.5 parts by weight of ADR4468 compatibilizer, and 8 parts by weight of talc-modified PBAT masterbatch. In the talc-modified PBAT masterbatch, the talc is in the form of lamellar sheets, approximately 5 μm in length and 5 μm in width, and the mass ratio of PBAT resin to talc is 1:1.

[0100] Example 8

[0101] A toughened modified PGA composite material, whose composition and preparation method are basically the same as those in Example 1, except that it includes the following raw materials in parts by weight:

[0102] 100 parts by weight of PGA (molecular weight 500,000, melting temperature 220-230℃), 40 parts by weight of PBAT resin, 1.5 parts by weight of ADR4468 compatibilizer, and 20 parts by weight of talc-modified PBAT masterbatch. In the talc-modified PBAT masterbatch, the talc is in the form of lamellar sheets, approximately 5 μm in length and 5 μm in width, and the mass ratio of PBAT resin to talc is 1:1.

[0103] The toughened modified PGA composite materials prepared in Examples 7 and 8 were fabricated into sheets using a vacuum press. The vacuum press temperature was 230℃, the pressure was 2000 kg, the preheating time was 3 min, and the hot pressing time was 2 min. The resulting sheets were then cut into standard samples using a dumbbell-shaped cutter. The tensile strength of the standard samples was tested using a tensile testing machine according to ASTM D638-2014 standard, at a tensile rate of 1 mm / min. The test results are shown in Table 4 below.

[0104] Table 4

[0105] Group Talc masterbatch content Tensile strength (MPa) Elongation at break (%) Example 2 15 portions by weight 37.5±1.9 13.3±0.8 Example 7 8 portions by weight 19.6±3.1 8.7±1.3 Example 8 20 portions by weight 39.6±1.6 12.2±2.8

[0106] Table 4 shows the effect of different inorganic filler contents on the mechanical properties of toughened modified PGA composites: adding talc to modify PBAT masterbatch can promote the dispersion of talc particles and reduce the phase size of PBAT resin particles, thereby improving the toughening effect of PBAT resin and increasing the strength of the composite. In addition, the presence of talc can reduce the shrinkage rate of the composite, improve stiffness, increase the service life of the product, and reduce production costs. As shown in Comparative Example 2 below, without inorganic fillers, the PBAT resin particles are relatively large, which affects the mechanical properties of the composite. However, talc and polymer materials do not react and are incompatible. In Example 8, the high talc content weakens the intermolecular interactions of the polymer materials, affecting the strength and toughness of the composite.

[0107] Example 9

[0108] A toughened modified PGA composite material, whose composition and preparation method are basically the same as those in Example 1, except that it includes the following raw materials in parts by weight:

[0109] 100 parts by weight of PGA (molecular weight 500,000, melting temperature 220-230℃), 32.5 parts by weight of PBAT resin, 1.5 parts by weight of ADR4468 compatibilizer, and 22.5 parts by weight of talc-modified PBAT masterbatch. In the talc-modified PBAT masterbatch, the talc is in the form of lamellar sheets, approximately 5 μm in length and 5 μm in width, and the mass ratio of PBAT resin to talc is 2:1.

[0110] Example 10

[0111] A toughened modified PGA composite material, whose composition and preparation method are basically the same as those in Example 1, except that it includes the following raw materials in parts by weight:

[0112] 100 parts by weight of PGA (molecular weight 500,000, melting temperature 220-230℃), 17.5 parts by weight of PBAT resin, 1.5 parts by weight of ADR4468 compatibilizer, and 37.5 parts by weight of talc-modified PBAT masterbatch. In the talc-modified PBAT masterbatch, the talc is in the form of lamellar sheets, approximately 5 μm in length and 5 μm in width, and the mass ratio of PBAT resin to talc is 4:1.

[0113] The toughened modified PGA composite materials prepared in Examples 9 and 10 were fabricated into sheets using a vacuum press. The vacuum press temperature was 230℃, the pressure was 2000 kg, the preheating time was 3 min, and the hot pressing time was 2 min. The resulting sheets were then cut into standard samples using a dumbbell-shaped cutter. The tensile strength of the standard samples was tested using a tensile testing machine according to ASTM D638-2014 standard, at a tensile rate of 1 mm / min. The test results are shown in Table 5.

[0114] Table 5

[0115]

[0116] As shown in Table 5, the mechanical strength and elongation at break of the composite material slightly decreased with the increase of PBAT content in the masterbatch. The talc content in the composite material remained unchanged, but the increased content of talc-modified PBAT masterbatch led to a higher content of secondary-processed PBAT resin in the composite material. PBAT resin may degrade after secondary extrusion, thus causing a slight decrease in the mechanical strength and elongation at break of the composite material.

[0117] Example 11

[0118] A toughened modified PGA composite material, whose composition and preparation method are basically the same as those in Example 1, except that it includes the following raw materials in parts by weight:

[0119] 100 parts by weight of PGA (molecular weight 1 million, melting temperature 220-230℃), 40 parts by weight of PBAT resin, 1.5 parts by weight of ADR4468 compatibilizer, and 15 parts by weight of talc-modified PBAT masterbatch. In the talc-modified PBAT masterbatch, the talc is in the form of lamellar sheets, approximately 5 μm in length and 5 μm in width, and the mass ratio of PBAT resin to talc is 1:1.

[0120] The toughened modified PGA composite material prepared in Example 11 was used to prepare sheets using a vacuum press. The vacuum press temperature was 230℃, the pressure was 2000 kg, the preheating time was 3 min, and the hot pressing time was 2 min. The prepared sheets were then used to prepare standard samples using a dumbbell-shaped cutter. The tensile strength of the standard samples was tested using a tensile testing machine according to ASTM D638-2014 standard, at a tensile rate of 1 mm / min. The test results are shown in Table 6.

[0121] Table 6

[0122] Group PGA molecular weight Tensile strength (MPa) Elongation at break (%) Example 2 50 37.5±1.9 13.3±0.8 Example 11 100 33.1±1.6 15.6±1.1

[0123] As shown in Table 6, the composite material prepared using PGA with a molecular weight of 1 million has a lower tensile strength than the PGA composite material with a lower molecular weight, but a higher elongation at break. This is because the higher the molecular weight of PGA, the weaker its crystallinity, the lower its mechanical strength, and the better its toughness. Therefore, the composite material prepared using high molecular weight PGA has good toughness, but its strength is affected.

[0124] Example 12

[0125] A toughened modified PGA composite material, whose composition and preparation method are basically the same as those in Example 1, except that it includes the following raw materials in parts by weight:

[0126] The mixture comprises 100 parts by weight of PGA (molecular weight 500,000, melting temperature 220-230℃), 40 parts by weight of PBAT resin, 1.5 parts by weight of ADR4468 compatibilizer, and 15 parts by weight of talc-modified PBAT masterbatch. In the talc-modified PBAT masterbatch, the talc is in lamellar form, approximately 10 μm in length and 10 μm in width, and the mass ratio of PBAT resin to talc is 1:1.

[0127] Example 13

[0128] A toughened modified PGA composite material, whose composition and preparation method are basically the same as those in Example 1, except that it includes the following raw materials in parts by weight:

[0129] 100 parts by weight of PGA (molecular weight 500,000, melting temperature 220-230℃), 40 parts by weight of PBAT resin, 1.5 parts by weight of ADR4468 compatibilizer, and 15 parts by weight of talc-modified PBAT masterbatch. In the talc-modified PBAT masterbatch, the talc is in the form of lamellar sheets, approximately 15 μm in length and 15 μm in width, and the mass ratio of PBAT resin to talc is 1:1.

[0130] The toughened modified PGA composite materials prepared in Examples 12 and 13 were fabricated into sheets using a vacuum press. The vacuum press temperature was 230°C, the pressure was 2000 kg, the preheating time was 3 min, and the hot pressing time was 2 min. The resulting sheets were then cut into standard samples using a dumbbell-shaped cutter. The tensile strength of the standard samples was tested using a tensile testing machine according to ASTM D638-2014 standard, at a tensile rate of 1 mm / min. The test results are shown in Table 7.

[0131] Table 7

[0132] Group Talc size (μm) Tensile strength (MPa) Elongation at break (%) Example 2 5 37.5±1.9 13.3±0.8 Example 12 10 24.1±1.1 8.6±0.9 Example 13 15 22.5±2.3 8.5±0.3

[0133] As can be seen from Table 7, the mechanical strength and fracture elongation of the composite material decrease significantly with the increase of talc particle size. This is because the size of the inorganic filler increases, the bonding force between PGA resin and talc decreases, which in turn leads to a decrease in the mechanical strength and fracture elongation of the composite material.

[0134] Comparative Example 2

[0135] A PGA composite material comprising the following parts by weight of raw materials:

[0136] 100 parts by weight of PGA (molecular weight of 500,000, melting temperature of 220-230℃), 40 parts by weight of PBAT resin, and 1.5 parts by weight of ADR4468 compatibilizer.

[0137] The preparation method of the above-mentioned PGA composite material includes the following steps:

[0138] 100 parts by weight of PGA, 40 parts by weight of PBAT resin, and 1.5 parts by weight of ADR4468 compatibilizer were vacuum dried separately at a temperature of 60℃, a vacuum degree of 80KPa, and a time of 12h. The vacuum-dried PGA, PBAT resin, and ADR4468 compatibilizer were then mixed evenly and extruded into an extruder. The temperatures of heating zone 1, heating zone 2, heating zone 3, and the die of the extruder were 180℃, 210℃, 230℃, and 210℃, respectively. The screw speed was 30rpm, and the mixing time was 6min. Then, the mixture was cooled, granulated, and dried at a temperature of 60℃, a vacuum degree of 80KPa, and a drying time of 6h to obtain the PGA composite material.

[0139] Comparative Example 3

[0140] A PGA composite material comprising the following parts by weight of raw materials:

[0141] 100 parts by weight of PGA (molecular weight of 500,000, melting temperature of 220-230℃), 47.5 parts by weight of PBAT resin, 1.5 parts by weight of ADR4468 compatibilizer, and 7.5 parts by weight of talc (lamellar, approximately 5μm in length and 5μm in width).

[0142] The preparation method of the above-mentioned PGA composite material includes the following steps:

[0143] 100 parts by weight of PGA, 47.5 parts by weight of PBAT resin, 1.5 parts by weight of ADR4468 compatibilizer, and 7.5 parts by weight of talc were vacuum dried separately at a temperature of 60℃, a vacuum degree of 80KPa, and a time of 12h. The vacuum-dried PGA, PBAT resin, ADR4468 compatibilizer, and talc were then mixed evenly and extruded into an extruder. The temperatures of heating zone 1, heating zone 2, heating zone 3, and the die of the extruder were 180℃, 210℃, 230℃, and 210℃, respectively. The screw speed was 30rpm, and the mixing time was 6min. Then, the mixture was cooled, granulated, and dried at a temperature of 60℃, a vacuum degree of 80KPa, and a drying time of 6h to obtain the PGA composite material.

[0144] The PGA composite materials prepared in Comparative Examples 2 and 3 were fabricated into sheets using a vacuum press. The vacuum press temperature was 230℃, the pressure was 2000 kg, the preheating time was 3 min, and the hot pressing time was 2 min. The resulting sheets were then cut into standard samples using a dumbbell-shaped cutter. The tensile strength of the standard samples was tested using a tensile testing machine according to ASTM D638-2014 standard, at a tensile rate of 1 mm / min. The test results are shown in Table 8 below.

[0145] Table 8

[0146] Group Inorganic packing morphology Tensile strength (MPa) Elongation at break (%) Example 2 Masterbatch 37.5±1.9 13.3±0.8 Comparative Example 2 / 7.5±2.9 6.9±0.6 Comparative Example 3 powder 25.3±3.4 7.5±1.3

[0147] Table 8 shows the effect of different inorganic filler morphologies and amounts on the mechanical properties of toughened modified PGA composites: Compared with Comparative Example 2, the mechanical strength and elongation at break of the PGA composite sheet in Comparative Example 3 were significantly improved after the addition of talc powder. This is because talc powder has a reinforcing effect on the composite and reduces the size of PBAT resin particles in the composite, thereby improving the mechanical properties of the composite. Compared with the toughened modified PGA composite sheet in Example 2, the mechanical strength and elongation at break of the composite were further improved after adding talc powder as masterbatch. This indicates that adding talc powder using the masterbatch method can improve the dispersion of talc powder in the composite and further enhance the reinforcing and toughening effect of talc powder on the composite.

[0148] Comparative Example 4

[0149] A PGA composite material comprising the following parts by weight of raw materials:

[0150] 100 parts by weight of PGA (molecular weight 500,000, melting temperature 220-230℃), 40 parts by weight of PBAT resin, 1.5 parts by weight of ADR4468 compatibilizer, and 15 parts by weight of calcium carbonate masterbatch. In the calcium carbonate masterbatch, the calcium carbonate is in granular form with a particle size of 5μm, and the mass ratio of PBAT resin to calcium carbonate is 1:1.

[0151] The preparation method of the above-mentioned PGA composite material includes the following steps:

[0152] (1) After mixing PBAT resin and nano calcium carbonate in a mass ratio of 1:1, the mixture is added to an extruder and extruded. The temperatures of heating zone 1, heating zone 2, heating zone 3 and die of the extruder are 130℃, 160℃, 170℃ and 180℃ respectively. The screw speed is 30 rpm and the mixing time is 6 min to prepare nano calcium carbonate modified PBAT masterbatch.

[0153] (2) 100 parts by weight of PGA, 40 parts by weight of PBAT resin, 1.5 parts by weight of ADR4468 compatibilizer, and 15 parts by weight of nano-calcium carbonate modified PBAT masterbatch were vacuum dried separately at a temperature of 60°C, a vacuum degree of 80 kPa, and a time of 12 h. The vacuum-dried PGA, PBAT resin, ADR4468 compatibilizer, and nano-calcium carbonate modified PBAT masterbatch were mixed evenly and extruded into an extruder. The temperatures of heating zone 1, heating zone 2, heating zone 3, and die of the extruder were 180°C, 210°C, 230°C, and 210°C, respectively. The screw speed was 30 rpm, and the mixing time was 6 min. Then, the mixture was cooled, granulated, and dried at a temperature of 60°C, a vacuum degree of 80 kPa, and a drying time of 6 h to obtain the PGA composite material.

[0154] The PGA composite material prepared in Comparative Example 4 was used to prepare sheets using a vacuum press. The vacuum press temperature was 230℃, the pressure was 2000 kg, the preheating time was 3 min, and the hot pressing time was 2 min. The prepared sheets were then used to prepare standard samples using a dumbbell-shaped cutter. The tensile strength of the standard samples was tested using a tensile testing machine according to ASTM D638-2014 standard, with a tensile rate of 1 mm / min. The test results are shown in Table 9 below.

[0155] Table 9

[0156] Group Inorganic packing morphology Tensile strength (MPa) Elongation at break (%) Example 2 Masterbatch 37.5±1.9 13.3±0.8 Comparative Example 4 Masterbatch 27±2.9 4.1±0.6

[0157] Table 9 shows the effects of different inorganic filler morphologies and dosages on the mechanical properties of toughened and modified PGA composites: After adding nano-calcium carbonate, the mechanical strength and elongation at break of the composite decreased, indicating that nano-calcium carbonate contributed little to the strength and toughness of the composite, and the mechanical properties of the composite did not achieve the expected reinforcing effect. When talc powder was made into masterbatch and added to the composite, the mechanical strength and elongation at break of the PGA / PBAT / talc composite were 37.5 MPa and 13.3%, respectively, which were 39% and 224% higher than those of the PGA / PBAT / calcium carbonate composite. This indicates that the reinforcing and toughening effect of talc on the composite is far better than that of calcium carbonate. This may be due to the different shapes of talc and calcium carbonate. Talc has a layered structure, while calcium carbonate has a granular structure. Therefore, with similar dimensions, the specific surface area of ​​talc is much larger than that of calcium carbonate. Furthermore, the layered structure of talc can effectively prevent the formation of large particles of PBAT resin, while the barrier effect of granular calcium carbonate on PBAT resin is relatively weak.

[0158] Comparative Example 5

[0159] A PGA composite material comprising the following parts by weight of raw materials:

[0160] 100 parts by weight of PGA (molecular weight 500,000, melting temperature 220-230℃), 40 parts by weight of PBAT resin, 1.5 parts by weight of MDI compatibilizer, and 15 parts by weight of talc-modified PBAT masterbatch. In the talc-modified PBAT masterbatch, the talc is in the form of lamellar sheets, approximately 5 μm in length and 5 μm in width, and the mass ratio of PBAT resin to talc is 1:1.

[0161] The preparation method of the above-mentioned PGA composite material includes the following steps:

[0162] (1) After mixing PBAT resin and talc powder evenly at a mass ratio of 1:1, add it to an extruder for extrusion. The temperatures of heating zone 1, heating zone 2, heating zone 3 and die of the extruder are 130℃, 160℃, 170℃ and 180℃ respectively. The screw speed is 30 rpm and the mixing time is 6 min to prepare talc-modified PBAT masterbatch.

[0163] (2) 100 parts by weight of PGA, 40 parts by weight of PBAT resin, 1.5 parts by weight of MDI compatibilizer, and 15 parts by weight of talc-modified PBAT masterbatch were vacuum dried at 60°C and 80 kPa for 12 hours. The vacuum-dried PGA, PBAT resin, MDI compatibilizer, and talc-modified PBAT masterbatch were mixed evenly and extruded into an extruder. The temperatures of heating zone 1, heating zone 2, heating zone 3, and die of the extruder were 180°C, 210°C, 230°C, and 210°C, respectively. The screw speed was 30 rpm and the mixing time was 6 minutes. Then, the mixture was cooled, granulated, and dried at 60°C and 80 kPa for 6 hours to obtain the PGA composite material.

[0164] The PGA composite material prepared in Comparative Example 7 was used to prepare sheets using a vacuum press. The vacuum press temperature was 230℃, the pressure was 2000 kg, the preheating time was 3 min, and the hot pressing time was 2 min. The prepared sheets were then used to prepare standard samples using a dumbbell-shaped cutter. The tensile strength of the standard samples was tested using a tensile testing machine according to ASTM D638-2014 standard, with a tensile rate of 1 mm / min. The test results are shown in Table 10 below.

[0165] Table 10

[0166] Group compatibilizer Tensile strength (MPa) Elongation at break (%) Example 2 ADR4468 37.5±1.9 13.3±0.8 Comparative Example 5 MDI 13.1±1.2 6.0±0.7

[0167] Table 10 shows that different compatibilizers have different effects on the mechanical properties of toughened modified PGA composites. Compared with Example 2, the mechanical strength and elongation at break of the composite material prepared in Comparative Example 5 are significantly reduced. This is because, compared with ADR4468, MDI lacks epoxy groups and has a smaller effect on improving the compatibility of the composite material, thus resulting in a lower elongation at break for the PGA / PBAT / MDI composite material.

[0168] The foregoing has described preferred embodiments of the present invention. However, it should be understood that the invention is not limited to the content disclosed herein. Any non-substantial improvements made using the inventive concept and technical solution, or any application of the inventive concept and technical solution to other situations, are within the protection scope of the present invention.

Claims

1. A toughened modified polyglycolic acid composite material comprising the following blended components: PBAT masterbatch modified with polyglycolic acid, PBAT resin, compatibilizer and inorganic filler; Based on 100 parts by weight of polyglycolic acid: 2-65 parts by weight of PBAT resin; Compatibilizer 0.5-3.5 parts by weight; 5-40 parts by weight of inorganic filler-modified PBAT masterbatch.

2. The polyglycolic acid composite material according to claim 1, characterized in that: Based on 100 parts by weight of polyglycolic acid: 5-60 parts by weight of PBAT resin; Compatibilizer 0.8–3 parts by weight; 8-37.5 parts by weight of inorganic filler modified PBAT masterbatch.

3. The polyglycolic acid composite material according to claim 1, characterized in that: The inorganic filler-modified PBAT masterbatch comprises a blend of PBAT resin and inorganic particulate powder; preferably, The inorganic granular powder is talc; more preferably, the talc is in the form of lamellae; even more preferably, the length of the lamellae talc is 2-20 μm, preferably 5-15 μm, and / or the width is 2-20 μm, preferably 5-15 μm.

4. The polyglycolic acid composite material according to claim 1, characterized in that: The mass ratio of PBAT resin to inorganic granular powder in the inorganic filler modified PBAT masterbatch is (1-20):1, preferably (1-4):

1.

5. The polyglycolic acid composite material according to claim 1, characterized in that: The compatibilizer is at least one of epoxy compatibilizers, preferably, the epoxy equivalent of the epoxy compatibilizer is 260-280.

6. The polyglycolic acid composite material according to claim 1 or 2, characterized in that: The polyglycolic acid has a molecular weight of 300,000 to 1,000,000 and / or a melting temperature of 210 to 230°C.

7. The polyglycolic acid composite material according to claim 1 or 2, characterized in that: The inorganic filler-modified PBAT masterbatch is prepared by melt blending components including PBAT resin and inorganic particulate powder.

8. A method for preparing a toughened modified polyglycolic acid composite material as described in any one of claims 1-7, the method comprising: The polyglycolic acid composite material is prepared by melt blending the components, including the polyglycolic acid, PBAT resin, compatibilizer and inorganic filler modified PBAT masterbatch, in the amounts specified above. Preferably, the method includes: (1) After the components including PBAT resin and inorganic filler are mixed evenly, inorganic filler modified PBAT masterbatch is obtained by melt blending. (2) The dried polyglycolic acid, PBAT resin, compatibilizer, and inorganic filler modified PBAT masterbatch are mixed evenly in proportion and the polyglycolic acid composite material is obtained by melt blending.

9. The preparation method according to claim 8, characterized in that: In step (1): The extruder heating zone used for melt blending comprises four sections from feeding to extrusion, preferably... The temperature of the first heating zone of the extruder is 100–130°C, and / or the temperature of the second heating zone is 140–160°C, and / or the temperature of the third heating zone is 170–190°C, and / or the die temperature is 180–200°C; and / or, The screw speed of the extruder is 10–60 rpm; and / or, The blending time is 3–12 min; And / or, In step (2): The extruder heating zone used for melt blending comprises four sections from feeding to extrusion, preferably... The temperature of heating zone one of the extruder is 180–200°C, and / or the temperature of heating zone two is 205–220°C, and / or the temperature of heating zone three is 220–240°C, and / or the die temperature is 190–210°C; and / or, The extruder screw speed is 10–60 rpm; and / or, The blending time is 2 to 12 minutes, preferably 3 to 10 minutes.

10. The preparation method according to claim 8, characterized in that: In step (2): The drying process employs vacuum drying. Preferably, the vacuum drying temperature is 30–80°C, and / or the vacuum degree is 10–80 kPa, and / or the time is 6–24 hours; and / or, The polyglycolic acid composite material is obtained by cooling, granulation and drying after melt blending. Preferably, the drying is carried out by vacuum drying. More preferably, the vacuum drying temperature is 30-80℃ and / or the vacuum degree is 10-80KPa and / or the time is 6-24h.

11. A polyglycolic acid composite material sheet, wherein the sheet is prepared by vacuum pressing of a toughened modified polyglycolic acid composite material obtained by any one of the preparation methods of claims 1-7 or claims 8-10.

12. The plate according to claim 11, characterized in that: The vacuum pressing temperature is 225–240℃, and / or the pressure is 1000–5000 kg, and / or the preheating time is 3–10 min, and / or the hot pressing time is 1–3 min.

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