High mineral powder filled biodegradable film material and method of making same

Abstract

The application provides a high-filler-filled biodegradable material and a preparation method thereof, and belongs to the field of polymer materials.The biodegradable film material comprises the following components: 30-65 parts of PBAT resin, 1-10 parts of PLA resin, 1-5 parts of a plasticizing coupling modifier, 35-55 parts of filler, and 0-1 part of an opening agent.The plasticizing coupling modifier is prepared by copolymerization of raw materials comprising a capped polyester plasticizer, a vinyl silane coupling agent and glycidyl methacrylate under the action of an initiator, and the side chain has a large number of polydiacid-diglycol ester plasticizing groups and silane coupling groups, so that the PBAT resin, the PLA resin and the filler can be combined through hydrogen bonds and chemical bonds, and are fully infiltrated, and the plasticizing coupling modifier also has an epoxy group, which increases the compatibility of the PBAT and the PLA resin.The prepared biodegradable film has a higher filler ratio, a lower cost, fewer film crystal points and good mechanical properties.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of high polymer materials, and particularly relates to a high-mineral-powder-filled biodegradable film material and a preparation method thereof. BACKGROUND

[0002] The invention and use of plastics have brought great convenience to people's daily life, such as the application of shopping bags, straws, tableware, etc., but non-degradable plastics not only pollute the soil, atmosphere and water body, causing huge environmental safety hazards, but also seriously endanger human health through the transfer of the food chain.

[0003] Biodegradable plastic PBAT has good ductility and processability, and also has excellent biodegradability, and is one of the best degradable materials in the current application research of biodegradable film bags and has the best market application prospect, but the price of PBAT bag is more than twice that of traditional PE bag, and the acceptance of consumers is generally low.

[0004] In order to reduce the price of the material, the common modification method is to fill PBAT resin with mineral powder, and the mainstream mineral powder filling content on the market is not higher than 40%, and when the proportion exceeds this, the mineral powder is not uniformly dispersed, causing the material performance to decrease, and the surface of the film is very rough and has many crystal points, affecting the use of consumers.

[0005] CN113429754A discloses a composite-filled fully degradable material composition, a film and a preparation method thereof, which blends and modifies PBAT, organic filler, inorganic filler, plasticizer and coupling agent, but simple blending modification is not conducive to the dispersion of the filler. SUMMARY

[0006] The present application aims to provide a high-mineral-powder-filled biodegradable material, which has a higher mineral powder filling ratio of the degradable film, a lower cost, and fewer crystal points and good mechanical properties of the film.

[0007] To achieve the above-mentioned purpose, the technical solution adopted by the present application is as follows:

[0008] A high-mineral-powder-filled biodegradable film material, comprising the following components in mass parts:

[0009]

[0010] The plasticizing coupling modifier is prepared by copolymerization of raw materials including a capped polyester plasticizer, a vinyl silane coupling agent and glycidyl methacrylate.

[0011] The PBAT resin has a melt index of 2-8 g / 10 min (190 DEG C, 2.16 kg), preferably 3-5 g / 10 min (190 DEG C, 2.16 kg), and a weight average molecular weight of 130-170 thousand, preferably 140-160 thousand.

[0012] The PLA resin has a melt index of 2-8 g / 10 min (190 DEG C, 2.16 kg), preferably 4-7 g / 10 min (190 DEG C, 2.16 kg), and a light rotation purity of 92-99%, preferably 94-98%.

[0013] The mineral powder filling is one or more of calcium carbonate, talcum powder, mica and montmorillonite, and the mesh number of the mineral powder is 1000-10000 mesh, preferably 3000-8000 mesh.

[0014] The opening agent is one or more of oleic acid amide, erucic acid amide, ethylene bis-stearyl amide and silicon dioxide.

[0015] The preparation method of the plasticizing coupling modifier comprises the following steps:

[0016] (1) the end-capping agent and the polyester plasticizer are subjected to an end-capping reaction under the action of a catalyst in a three-necked flask to obtain an end-capped polyester plasticizer;

[0017] (2) the end-capped polyester plasticizer, vinyl silane coupling agent and glycidyl methacrylate are extruded in a banbury mixer under the action of an initiator to obtain the plasticizing coupling modifier.

[0018] In step (1), the mass ratio of the polyester plasticizer, the end-capping agent and the catalyst is 100:(1-2):(0.1-0.5).

[0019] In step (1), the polyester plasticizer is one or more of polypropylene glycol sebacate, polyethylene glycol adipate and polypropylene glycol adipate, and the number average molecular weight is 800-8000, preferably 1000-5000.

[0020] In step (1), the end-capping agent is one or more of acrylic acid, acrylic acid amide, methacrylic acid and glycidyl methacrylate.

[0021] Preferably, in step (1), the end-capping reaction temperature is 140-180 DEG C, the reaction time is 1-2 h, and the catalyst is one or more of tetrabutyl titanate, antimony trioxide and germanium dioxide.

[0022] The vinyl silane coupling agent in step (2) is one or more of vinyl tri(β-methoxyethoxy)silane, vinyl trimethoxysilane, vinyl triethoxysilane, and vinyl tri-tert-butyl peroxysilane.

[0023] The initiator in step (2) is one or more of dicumyl peroxide, benzoyl peroxide, and methyl ethyl ketone peroxide, and preferably the initiator is dicumyl peroxide.

[0024] The mass ratio of the capped polyester plasticizer, the vinyl silane coupling agent, the glycidyl methacrylate, and the initiator in step (2) is 1000:(100-400):(100-400):(0.2-2), and preferably the mass ratio of the capped polyester plasticizer, the vinyl silane coupling agent, the glycidyl methacrylate, and the initiator is 1000:(200-300):(200-300):(0.5-1.8).

[0025] The mixing reaction temperature in step (2) is 140-180℃, the rotation speed is 10-60rpm, and the reaction time is 10-80min, and preferably the mixing reaction temperature is 150-170℃, the rotation speed is 15-50rpm, and the reaction time is 15-60min.

[0026] Another object of the present application is to provide a method for preparing a biodegradable film material.

[0027] The method for preparing the biodegradable film material comprises the following steps:

[0028] The PBAT resin, the PLA resin, the plasticizing coupling modifier, the mineral powder, and the opening agent are mixed, and then added into a double-screw extruder, followed by melt extrusion, cooling, granulation, drying, to obtain the biodegradable film material, which is optionally blow molded in a single-screw film blowing machine.

[0029] In the method for preparing the biodegradable film material, the rotation speed of the double-screw extruder is 200-700rpm, and the extrusion temperature is 120-170℃.

[0030] In the method for preparing the biodegradable film material, the blow molding temperature of the single-screw film blowing machine is 150-180℃.

[0031] Compared with the prior art, the present application has the following technical advantages:

[0032] 1. The plasticizing coupling modifier side chain has a large number of dihydric alcohol diacid ester plasticizing groups and silane coupling groups, so that the PBAT resin, the PLA resin and the mineral powder can be combined by hydrogen bonds and chemical bonds, fully infiltrated, and also have epoxy groups, without additional addition of epoxy chain extenders, increasing the compatibility of the PBAT and the PLA resin, and reducing the material cost.

[0033] 2. The prepared degradable film has a higher mineral powder filling ratio, lower cost, fewer film crystal points and good mechanical properties. DETAILED DESCRIPTION

[0034] The application will be further described below by specific examples, and the examples described in the application are only used to illustrate the application and do not limit the scope of the application.

[0035] In each example and comparative example, the main raw materials are as follows in Table 1:

[0036] Table 1 Raw materials and sources

[0037]

[0038]

[0039] The performance test parameters and corresponding test methods of the biodegradable film material and the biodegradable film are as follows in Table 2:

[0040] Table 2 Performance test methods

[0041] Test Content Unit Test Method Film Thickness μm GB / T 6672 Tensile Strength MPa ISO 527.3 Elongation at Break ％ ISO 527.3 Crystal Point cm 2 ]] GB / T 6595

[0042] The processing equipment used is:

[0043] Double screw extruder, Kobe Long, model ZSK 26Mc 18, length-diameter ratio 52, screw diameter 26mm;

[0044] Banbury mixer, 15L;

[0045] Single screw film blowing machine, Zhenxin, length-diameter ratio 32, screw diameter 45mm;

[0046] The test equipment used is:

[0047] Germany ZWICK film tensile tester, tensile speed 500mm / min;

[0048] American 3Y company fish eye instrument.

[0049] Example 1

[0050] (1) Plasticizing coupling modifier A:

[0051] The polypropylene adipate polyester plasticizer number average molecular weight 1000, glycidyl methacrylate and tetrabutyl titanate were added into a three-necked flask in a mass ratio of 100:1.1:0.1, the reaction temperature was 140°C, and the reaction time was 2h to obtain glycidyl methacrylate-terminated polypropylene adipate polyester plasticizer.

[0052] The glycidyl methacrylate-terminated polypropylene adipate polyester plasticizer, vinyl tri(β-methoxyethoxy)silane, glycidyl methacrylate and dicumyl peroxide were mixed in a mass ratio of 1000:100:400:0.3, and then added into an internal mixer, the temperature was 170°C, the rotating speed was 50rpm, the reaction time was 15min, and extrusion granulation was performed to obtain plastic coupling modifier A.

[0053] (2) The biodegradable material was prepared by using plastic coupling modifier A and the components in Table 3 as raw materials, and referring to the amount of raw materials in Table 3, and the following method, the extrusion conditions were as follows: the screw rotating speed was 200rpm, and the screw temperature was set in sections from the feeding port to the die head as 120°C, 130°C, 135°C, 135°C, 140°C, 150°C, 150°C, 160°C, 160°C, 160°C and 160°C; the extruded material was cooled in the water tank of the extruder, pelletized, dried in a vacuum oven at 90°C for 4h to obtain the biodegradable material A, and then blow molded in a single screw film blowing machine at a blow molding temperature of 150°C.

[0054] Example 2

[0055] (1) Plastic coupling modifier B:

[0056] The polypropylene adipate polyester plasticizer number average molecular weight 3000, glycidyl methacrylate and tetrabutyl titanate were added into a three-necked flask in a mass ratio of 100:1.5:0.3, the reaction temperature was 150°C, and the reaction time was 1.5h to obtain glycidyl methacrylate-terminated polypropylene adipate polyester plasticizer.

[0057] The glycidyl methacrylate-terminated polypropylene adipate polyester plasticizer, vinyl trimethoxysilane, glycidyl methacrylate and methyl ethyl ketone peroxide were mixed in a mass ratio of 1000:400:100:1.8, and then added into an internal mixer, the temperature was 150°C, the rotating speed was 30rpm, the reaction time was 60min, and extrusion granulation was performed to obtain plastic coupling modifier B.

[0058] (2) The biodegradable material was prepared by using plasticizing coupling modifier A and the formulation components in Table 3 as raw materials, and referring to the raw material amount in Table 3, according to the following method. The extrusion conditions were: screw rotation speed 400 rpm, and the screw temperature was set in sections from the feeding port to the die head as 130℃, 130℃, 135℃, 135℃, 145℃, 150℃, 150℃, 160℃, 160℃, 165℃, 165℃. The extruded material was cooled in the water tank of the extruder, pelletized, and dried in a vacuum oven at 90℃ for 4h to obtain the biodegradable material B, which was then blow molded on a single screw film blowing machine at a blow molding temperature of 165℃.

[0059] Example 3

[0060] (1) Plasticizing coupling modifier C:

[0061] Polypropylene glycol sebacate polyester plasticizer with a number average molecular weight of 7000, methacrylic acid, and tetrabutyl titanate were added to a three-necked flask at a mass ratio of 100:2:0.5, and the reaction temperature was 170℃ for 1h to obtain methacrylic acid-terminated polypropylene glycol sebacate polyester plasticizer.

[0062] Methacrylic acid-terminated polypropylene glycol sebacate polyester plasticizer, vinyl trimethoxysilane, glycidyl methacrylate, and dicumyl peroxide were thoroughly mixed at a mass ratio of 1000:200:200:1.0, then added to a banbury mixer at a temperature of 160℃ and a rotation speed of 15 rpm, and reacted for 30 min, and then extruded and pelletized to obtain plasticizing coupling modifier C.

[0063] (2) The biodegradable material was prepared by using plasticizing coupling modifier A and the formulation components in Table 3 as raw materials, and referring to the raw material amount in Table 3, according to the following method. The extrusion conditions were: screw rotation speed 600 rpm, and the screw temperature was set in sections from the feeding port to the die head as 140℃, 140℃, 145℃, 145℃, 150℃, 150℃, 150℃, 165℃, 165℃, 165℃, 165℃. The extruded material was cooled in the water tank of the extruder, pelletized, and dried in a vacuum oven at 90℃ for 5h to obtain the biodegradable material C, which was then blow molded on a single screw film blowing machine at a blow molding temperature of 180℃.

[0064] Comparative Example 1

[0065] This comparative example directly used a commercially available silane coupling agent to replace the plasticizing coupling modifier, and prepared a biodegradable film according to the method in Example 1, with the only difference being the formulation composition in Table 3.

[0066] Comparative Example 2

[0067] The comparative example directly uses commercially available polyester plasticizer to replace the plasticizing coupling modifier, and the biodegradable film is prepared according to the method in Example 1, and the difference is only the composition of the formula in Table 3.

[0068] Comparative Example 3

[0069] The comparative example does not add a plasticizing coupling modifier, and the biodegradable film is prepared according to the method in Example 2, and the difference is only the composition of the formula in Table 3.

[0070] Comparative Example 4

[0071] The comparative example does not add a plasticizing coupling modifier, and the biodegradable film is prepared according to the method in Example 2, and the difference is only the composition of the formula in Table 3.

[0072] The performance test results of the biodegradable films obtained in Examples 1-3 and Comparative Examples 1-3 are shown in Table 4.

[0073] Table 3 Raw materials and amounts (Kg) in Examples 1-4 (S1-S3) and Comparative Examples 1-3 (D1-D3)

[0074] Raw Material S1 S2 S3 D1 D2 D3 D4 PBAT, Weight Average Molecular Weight 140,000 55.2 40.7 55.2 40.7 49.5 PBAT, Weight Average Molecular Weight 160,000 46.5 64.5 PLA Resin, Melt Index 4 g / 10 min 2 2 PLA Resin, Melt Index 6 g / 10 min 5 5 5 5 5 Plasticizing Coupling Modifier A 2 Plasticizing Coupling Modifier B 3 Plasticizing Coupling Modifier C 4 Vinyl Tris(β-methoxyethoxy)silane 2 Polypropylene Glycol Adipate 4 Calcium Carbonate (3000 Mesh) 40 50 40 50 Calcium Carbonate (8000 Mesh) 45 45 30 Eruic Acid Amide 0.8 0.3 0.8 0.3 Oleic Acid Amide 0.5 0.5 0.5

[0075] Table 4 Performance test results of products in Examples 1-4 (S1-S3) and Comparative Examples 1-3 (D1-D3)

[0076]

[0077]

[0078] As can be seen from Comparative Examples 1, 2 and Examples 1-3, directly adding commercially available silane coupling agent and polyester plasticizer, there are many crystal points, the tensile properties are poor, and there is no epoxy group, and the compatibility of PLA and PBAT is poor. As can be seen from Comparative Example 3 and Examples 1-3, without adding a plasticizing coupling modifier, the film surface is rough, the number of crystal points is >500 / 225cm 2 As can be seen from Comparative Example 4 and Examples 1-3, without adding a plasticizing coupling modifier at a low mineral powder ratio, the number of crystal points and the film performance are not as good as Examples 1-3. As can be seen from Examples 1-3, the biodegradable film prepared has a smooth appearance, excellent tensile properties, a mineral powder content of up to 50%, low cost, and strong market application value.

[0079] The above is only a preferred embodiment of the present application, and it should be noted that those skilled in the art can make several improvements and supplements without departing from the method of the present application, and these improvements and supplements should also be considered within the protection scope of the present application.

Claims

1. A high mineral powder filled biodegradable film material, characterized in that, Components comprising the following parts by mass: The plasticizing coupling modifier is prepared by copolymerization of raw materials comprising a capped polyester plasticizer, a vinyl silane coupling agent, and glycidyl methacrylate; The capped polyester plasticizer is obtained by a capping reaction of a capping agent and a polyester plasticizer under the action of a catalyst; the capping agent is one or more of acrylic acid, acrylic acid amide, methacrylic acid, and glycidyl methacrylate; the polyester plasticizer is one or more of polypropylene glycol sebacate, polyethylene glycol adipate, and polypropylene glycol adipate, with a number average molecular weight of 800-8000; The mineral powder has a mesh number of 1000-10000 mesh.

2. The biodegradable film material according to claim 1, characterized in that, Components comprising the following parts by mass: PBAT resin 35-60 parts PLA resin 2-8 parts Plasticizing coupling modifier 2-4 parts Mineral powder 40-50 parts Opening agent 0.2-0.8 parts.

3. The biodegradable film material according to claim 1 or 2, characterized in that, The PBAT resin has a melt index of 2-8 g / 10 min under a test condition of 190℃ and 2.16 kg, and a weight average molecular weight of 130-170 thousand.

4. The biodegradable film material according to claim 3, wherein The PBAT resin has a melt index of 3-5 g / 10 min under a test condition of 190℃ and 2.16 kg, and a weight average molecular weight of 140-160 thousand.

5. The biodegradable film material according to claim 1 or 2, wherein The PLA resin has a melt index of 2-8 g / 10 min under a test condition of 190℃ and 2.16 kg, and an optical rotation purity of 92-99%.

6. The biodegradable film material according to claim 5, wherein The PLA resin has a melt index of 4-7 g / 10 min under a test condition of 190℃ and 2.16 kg, and an optical rotation purity of 94-98%.

7. The biodegradable film material according to claim 1 or 2, wherein The mineral powder is one or more of calcium carbonate, talc, mica, and montmorillonite.

8. The biodegradable film material according to claim 1 or 2, wherein The opening agent is one or more of oleic acid amide, erucic acid amide, ethylene bis-stearyl amide, and silicon dioxide.

9. The biodegradable film material according to claim 1, wherein The preparation method of the plasticizing coupling modifier comprises the following steps: (1) A capping reaction of a capping agent and a polyester plasticizer under the action of a catalyst in a three-necked flask to obtain a capped polyester plasticizer; (2) A reaction extrusion of the capped polyester plasticizer, a vinyl silane coupling agent, and glycidyl methacrylate in a mixer under the action of an initiator to obtain a plasticizing coupling modifier.

10. The biodegradable film material according to claim 9, wherein In step (1), the mass ratio of the polyester plasticizer, the capping agent, and the catalyst is 100:(1-2):(0.1-0.5).

11. The biodegradable film material according to claim 9, wherein In step (1), the capping reaction temperature is 140-180℃, the reaction time is 1-2 h, and the catalyst is one or more of tetrabutyl titanate, antimony trioxide, and germanium dioxide.

12. The biodegradable film material according to claim 9, wherein In step (2), the vinyl silane coupling agent is one or more of vinyl tri(β-methoxyethoxy)silane, vinyl trimethoxysilane, vinyl triethoxysilane, and vinyl tri-tert-butyl peroxysilane.

13. The biodegradable film material according to claim 9 or 12, characterized in that, In step (2), the mass ratio of the capped polyester plasticizer, the vinyl silane coupling agent, glycidyl methacrylate, and the initiator is 1000:(100-400):(100-400):(0.2-2).

14. The biodegradable film material according to claim 13, wherein The mass ratio of the end-capped polyester plasticizer, vinyl silane coupling agent, glycidyl methacrylate and initiator in step (2) is 1000:(200-300):(200-300):(0.5-1.8).

15. The biodegradable film material according to claim 9 or 12, wherein The temperature of the internal mixing reaction in step (2) is 140-180℃, the rotation speed is 10-60rpm, and the reaction time is 10-80min.

16. The biodegradable film material according to claim 15, wherein The temperature of the internal mixing reaction in step (2) is 150-170℃, the rotation speed is 15-50rpm, and the reaction time is 15-60min.

17. The method of claim 1-16, comprising the steps of: mixing PBAT resin, PLA resin, plasticizing coupling modifier, mineral powder, opening agent, and then adding into a twin-screw extruder, followed by melt extrusion, cooling, granulation, drying, to obtain a biodegradable film material, and optionally blow molding in a single screw film blowing machine.

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