Composition, degradable material and application thereof

Abstract

The invention relates to a composition, a degradable material and application of the degradable material. The composition comprises polyadipic acid / butylene terephthalate, polylactic acid and butanediol / trimellitic anhydride modified epoxy resin. The composition according to one embodiment of the present invention comprises a butylene glycol / trimellitic anhydride modified epoxy resin and a poly (butylene adipate / terephthalate), in which the butylene glycol / trimellitic anhydride modified epoxy resin is capable of reacting with the poly (butylene adipate / terephthalate). When the composition is used for preparing a film, precipitation of poly (butylene adipate-co-terephthalate) after film preparation can be reduced, and the edge sealing performance of the film is improved.

Description

Technical Field

[0001] The invention relates to a composition that can be used for film making, in particular to a composition that can improve the edge sealing timeliness of a film. Background Art

[0002] In the garment bags and express logistics industries, edge-sealed film bags are often used as packaging materials. Most of the current packaging materials are based on PE materials, but since such materials are not biodegradable, direct disposal after use will cause major pollution problems. Bio-based degradable polymer materials can be derived from animals and plants without relying on increasingly scarce petroleum resources, and can be self-decomposed under the action of soil, enzymes, etc. to reduce environmental pollution. This material conforms to the current global trend of environmentally friendly products and has received widespread attention and research. Among them, special materials for degradable edge-sealed film bags have also been developed and gradually applied in the market.

[0003] Since edge-sealed film bag packaging products (such as express bags, milk tea bags, clothing bags, etc.) are first blown and printed, and then bagged, the film blowing capacity and bag-making capacity of different manufacturers are not completely matched. The film after production may be placed for 1 to 2 weeks before bagging, which will cause the edge seal to be loose during bagging, affecting the quality of the film bag. In addition, in order to control costs, some manufacturers will add recycled materials, or even increase the mineral powder filling of materials to reduce material costs, which leads to further compression of the edge sealing timeliness of the film, seriously affecting the promotion of such materials in related industries. Summary of the invention

[0004] To overcome at least one defect of the above-mentioned prior art, in a first aspect, one embodiment of the present invention provides a composition comprising poly(butylene adipate / terephthalate), poly(lactic acid) and butanediol / trimellitic anhydride modified epoxy resin.

[0005] In a second aspect, an embodiment of the present invention provides a degradable material, which is obtained by mixing and reacting the components of the above composition and then molding them.

[0006] In a third aspect, an embodiment of the present invention provides use of the above-mentioned composition or the above-mentioned degradable material in preparing a degradable film.

[0007] In a fourth aspect, an embodiment of the present invention provides a degradable film, which is prepared using the above-mentioned composition or the above-mentioned degradable material.

[0008] In a fifth aspect, an embodiment of the present invention provides a film bag made from the above-mentioned degradable film.

[0009] A composition according to one embodiment of the present invention comprises an epoxy resin modified with butanediol / trimellitic anhydride and polybutylene adipate / terephthalate, wherein the epoxy resin modified with butanediol / trimellitic anhydride can react with polybutylene adipate / terephthalate, so that the composition is used for film making to reduce the precipitation of polybutylene adipate / terephthalate after film making and improve the edge sealing performance of the film. DETAILED DESCRIPTION

[0010] Typical embodiments that embody the features and advantages of the present invention will be described in detail in the following description. It should be understood that the present invention can have various changes in different embodiments without departing from the scope of the present invention, and the descriptions therein are essentially used as illustrations rather than to limit the present invention.

[0011] One embodiment of the present invention provides a composition including polybutylene adipate / terephthalate (PBAT), polylactic acid (PLA) and butanediol / trimellitic anhydride modified epoxy resin (abbreviated as "BDODET").

[0012] In one embodiment, the mass content of polybutylene adipate / terephthalate in the composition can be 65-80wt%, and can further be 70-80wt%, for example, 66wt%, 67wt%, 68wt%, 69wt%, 71wt%, 72wt%, 73wt%, 74wt%, 75wt%, 76wt%, 77wt%, 78wt%, 79wt%, and the above contents are based on the total weight of the composition.

[0013] In one embodiment, the mass content of polylactic acid in the composition can be 3-8wt%, further can be 5-7wt%, for example, 4wt%, 6wt%, and the above content is based on the total weight of the composition.

[0014] In one embodiment, the mass content of the epoxy resin modified by butanediol / trimellitic anhydride in the composition can be 0.2-2wt%, and can further be 0.2-1wt%, for example, 0.3wt%, 0.4wt%, 0.5wt%, 0.6wt%, 0.7wt%, 0.8wt%, 0.9wt%, 1.2wt%, 1.5wt%, 1.8wt%, and the above contents are based on the total weight of the composition.

[0015] In one embodiment, the epoxy resin modified by butanediol / trimellitic anhydride is prepared by reacting butanediol, epoxy resin and trimellitic anhydride. Further, the reaction of butanediol, epoxy resin and trimellitic anhydride can be carried out under the catalysis of a boron trifluoride complex, and the boron trifluoride complex can be, for example, a boron trifluoride ether complex, and the amount of the boron trifluoride complex can be 4 to 6 mol% of the amount of trimellitic anhydride, such as 4.5 mol%, 5 mol%, 5.5 mol%.

[0016] In one embodiment, in the preparation of the butanediol / trimellitic anhydride modified epoxy resin, butanediol and trimellitic anhydride are first reacted, and then the reaction product is reacted with the epoxy resin.

[0017] In one embodiment, the butanediol may be 1,4-butanediol (BDO).

[0018] In one embodiment, in the epoxy resin modified by butanediol / trimellitic anhydride, the molar ratio of the trimellitic anhydride structure to the butanediol structure may be 2:1, and the molar ratio of the trimellitic anhydride structure to the epoxy resin structure may be 1:1. That is, in the preparation of the epoxy resin modified by butanediol / trimellitic anhydride, firstly, esterification is performed by one molecule of butanediol and two molecules of trimellitic anhydride to obtain a product of "trimellitic acid structure-butanediol structure-trimellitic acid structure", and then the product is reacted with epoxy resin to obtain a butanediol / trimellitic anhydride modified epoxy resin having a structure of "epoxy resin-trimellitic acid structure-butanediol structure-trimellitic acid structure-epoxy resin".

[0019] In one embodiment, in the preparation of butanediol / trimellitic anhydride modified epoxy resin, the molar ratio of trimellitic anhydride to butanediol can be (1.9-2.1):1, for example, 2:1; the molar ratio of trimellitic anhydride to epoxy resin can be (0.9-1.1):1, for example, 1:1.

[0020] In one embodiment, the epoxy resin is a two-part A-type epoxy resin, such as epoxy 128.

[0021] In one embodiment, the epoxy equivalent of the epoxy resin is 180-200, such as 190.

[0022] In one embodiment, in the preparation of the epoxy resin modified by butanediol / trimellitic anhydride, butanediol and trimellitic anhydride are first reacted, and when the reaction esterification rate reaches 96%, a clear solution is obtained, and then the epoxy resin is added to react.

[0023] In one embodiment, the number average molecular weight of the epoxy resin modified with butanediol / trimellitic anhydride is 1500-2500, for example, 1600, 1700, 1800, 2000, 2200, 2300, 2400.

[0024] In one embodiment, the epoxy resin modified by butanediol / trimellitic anhydride comprises hydroxyl, carboxyl and epoxy functional groups, and has one epoxy functional group at each end.

[0025] In one embodiment, the preparation method of the epoxy resin modified by butanediol / trimellitic anhydride comprises the following steps:

[0026] Under the action of boron trifluoride ether complex, butanediol and trimellitic anhydride are reacted at 65-70°C for 2.5-3h; then, epoxy resin (such as epoxy resin 128) is added to the system and reacted at 85-95°C (such as 90°C) for 6-7h (such as 6.5h) to obtain butanediol / trimellitic anhydride modified epoxy resin.

[0027] In one embodiment, polybutylene adipate / terephthalate is an existing flexible degradable polyester elastomer.

[0028] In one embodiment, the melt flow rate (or melt index) of polybutylene adipate / terephthalate at 200° C. and a load of 2.16 kg is 2 to 5 g / 10 min, for example, 3 g / 10 min, 4 g / 10 min.

[0029] In one embodiment, the melt flow ratio of polybutylene adipate / terephthalate (PBAT) may be less than 30, and may further be 20 to 30, such as 22, 25, or 28, where the melt flow ratio refers to the ratio of the melt flow rate of PBAT at 200° C. under a load of 21.6 kg to a load of 2.16 kg.

[0030] In one embodiment, the weight average molecular weight of polybutylene adipate / terephthalate may be 100,000 to 200,000, for example, 120,000, 140,000, 150,000, 160,000, or 180,000.

[0031] In one embodiment, the polylactic acid includes L-type polylactic acid and / or D-type polylactic acid.

[0032] In one embodiment, the polylactic acid includes L-type polylactic acid and D-type polylactic acid, the mass content of the L-type polylactic acid can be 90-95wt%, for example, 91wt%, 92wt%, 93wt%, 94wt%; the mass content of the D-type polylactic acid can be 5-10wt%, for example, 6wt%, 7wt%, 8wt%, 9wt%; wherein the sum of the mass contents of the L-type polylactic acid and the D-type polylactic acid is 100wt%.

[0033] In one embodiment, the melt flow rate (melt index) of polylactic acid at 190°C and 2.16 kg load can be 0.2 to 30 g / 10 min, and can further be 2 to 20 g / 10 min, for example, 0.5 g / 10 min, 1 g / 10 min, 4 g / 10 min, 5 g / 10 min, 6 g / 10 min, 7 g / 10 min, 9 g / 10 min, 10 g / 10 min, 12 g / 10 min, 15 g / 10 min, 18 g / 10 min, 19 g / 10 min, 21 g / 10 min, 22 g / 10 min, and 25 g / 10 min.

[0034] In one embodiment, the composition includes polybutylene adipate / terephthalate, polylactic acid and epoxy resin modified by butanediol / trimellitic anhydride, and one or more of mineral powder, an opening agent, and a lubricant.

[0035] In one embodiment, the mineral powder may be calcium carbonate and / or talcum powder; the particle size of the mineral powder may be 3000-5000 meshes.

[0036] In one embodiment, the lubricant may be one or more of monoglyceride, calcium stearate, and stearic acid.

[0037] In one embodiment, the opening agent may be polyethylene wax and / or silicon dioxide.

[0038] In one embodiment, the content of the mineral powder in the composition may be 12-30wt%, further may be 15-25wt%, for example 18wt%, 20wt%, 22wt%.

[0039] In one embodiment, the content of the opening agent in the composition may be 0.1 to 0.3 wt %, and further may be 0.2 to 0.3 wt %.

[0040] In one embodiment, the content of the lubricant in the composition may be 0.1 to 0.3 wt %, and further may be 0.2 to 0.3 wt %.

[0041] One embodiment of the present invention provides the use of the above-mentioned butanediol / trimellitic anhydride modified epoxy resin in the preparation of films, especially degradable films.

[0042] One embodiment of the present invention provides a degradable material, which is prepared by mixing and reacting the components of the above composition.

[0043] In one embodiment, the components of the above composition can be mixed and reacted at 170-200° C. and processed into a shape to prepare a degradable material.

[0044] In one embodiment, the melt flow rate of the degradable material at 190°C and a load of 2.16 kg is 1.4 to 2.5 g / 10 min, for example, 1.5 g / 10 min, 1.6 g / 10 min, 1.7 g / 10 min, 1.8 g / 10 min, 1.9 g / 10 min, 2.0 g / 10 min, 2.1 g / 10 min, and 2.3 g / 10 min.

[0045] One embodiment of the present invention provides a degradable film, which is made from the above-mentioned composition or degradable material.

[0046] One embodiment of the present invention provides a method for preparing the above-mentioned degradable film, comprising preparing the degradable film by using the above-mentioned composition or degradable material.

[0047] In one embodiment, the method for preparing the degradable film comprises the following steps:

[0048] Extruding the above composition at 170-200° C. (e.g., extrusion granulation) to obtain a degradable composite material;

[0049] The degradable composite material is made into a degradable film through a film making process.

[0050] In one embodiment, the extrusion process can be carried out in existing equipment, such as a twin-screw extruder.

[0051] In one embodiment, the film making process may be an existing technology, such as a blown film process. Further, the film blowing temperature in the blown film process may be 150-165°C, such as 152°C, 155°C, 158°C, 160°C, 162°C.

[0052] In one embodiment, the extrusion temperature may be 175°C, 180°C, 185°C, 190°C, or 195°C.

[0053] In one embodiment, PLA, PBAT, BDODET, mineral powder, anti-blocking agent, and lubricant are put into a high-speed mixer according to the ratio and mixed for 10 to 15 minutes to obtain a uniformly mixed premix; then the premix is ​​added to a silo of a twin-screw extruder, and extrusion granulation is performed at 170 to 200° C. to obtain PLA composite material particles with high melt strength.

[0054] One embodiment of the present invention provides a film bag, in particular an edge-sealed film bag, which is made from the above-mentioned degradable film or the above-mentioned degradable material. Furthermore, the film bag can be used as a packaging bag.

[0055] A composition according to one embodiment of the present invention includes BDODET and PBAT, wherein BDODET can react with PBAT to further increase the molecular weight of PBAT (especially the small molecules contained in PBAT), reduce the precipitation of small molecules in the material or film, and improve the edge sealing performance of the film.

[0056] The degradable material or degradable film of one embodiment of the present invention can be combined with the surface of the mineral powder because BDODET contains functional groups such as carboxyl and hydroxyl groups, thereby improving the dispersibility of the mineral powder, increasing the filling content of the mineral powder, and reducing the cost of the material.

[0057] The degradable material of one embodiment of the present invention can be used for film production at high production capacity. The prepared film has high edge sealing strength and long edge sealing time, and is suitable for the logistics packaging industry.

[0058] The method for preparing a degradable material or a degradable film according to one embodiment of the present invention can promote the reaction of BDODET and PBAT through the high temperature and shearing effect of a twin-screw extruder.

[0059] The preparation method of one embodiment of the present invention has a simple process, and the material can be obtained by reactive extrusion, and then the film-making process can be directly performed, thus avoiding the complicated treatment process of some additives in the traditional method, and the production efficiency is higher.

[0060] The degradable film or film bag of one embodiment of the present invention has good edge sealing timeliness and can be used as express packaging. The good edge sealing timeliness means that after the film is made and the film is used for bag edge sealing, the edge sealing hand tearing meets the sawtooth requirements and the edge sealing strength remains basically unchanged. That is, after the film is placed for a relatively long time, its performance can still meet the bag making requirements.

[0061] The following is a further description of the preparation of the degradable material and the film thereof according to an embodiment of the present invention in combination with examples. The raw materials and test methods involved in each example and comparative example are as follows.

[0062] raw material

[0063] 1. 2003D: PLA, melt flow rate at 190°C and 2.16kg load is 5g / 10min, produced by NatureWorks, USA;

[0064] 2. 3001D: PLA, melt flow rate at 190°C and 2.16kg load is 20g / 10min, produced by NatureWorks, USA;

[0065] 3. T16: PBAT, melt flow rate at 200°C and 2.16kg load is 4g / 10min, melt flow ratio is 28, weight average molecular weight is 140,000-150,000, produced by Wanhua Chemical;

[0066] 4. CC3000: 3000 mesh heavy calcium carbonate, Guangyuan Chemical;

[0067] 5. AH51205: 3000-5000 mesh talc powder, Liaoning Aihai;

[0068] 6. Opening agent: polyethylene wax, commercially available;

[0069] 7. Lubricant: magnesium stearate, commercially available;

[0070] 8. Epoxy resin: Nan Ya Epoxy 128, epoxy equivalent 180-190.

[0071] 9. Trimellitic anhydride: analytical grade, Shanghai Aladdin Biochemical Technology Co., Ltd.

[0072] 10. Boron trifluoride ether complex: analytical grade, Shanghai Aladdin Biochemical Technology Co., Ltd.

[0073] 11. 1,4-Butanediol: analytical grade, Shanghai Aladdin Biochemical Technology Co., Ltd.

[0074] Test Method

[0075] 1. Melt flow rate test

[0076] The melt flow rate was measured using INSTRON CEAST MF30 according to ISO1133.

[0077] 2. Film edge seal strength test

[0078] The edge seal strength of the film was measured using a single column testing machine (model ZWICK Z0.5TH) according to QB / T 2358.

[0079] 3. Film puncture strength test

[0080] The puncture strength of the film was measured using a single column testing machine (model ZWICK Z0.5TH) according to GB / T 37841.

[0081] 4. Material particle aging test

[0082] The material was aged at 85% RH and 85°C for 3 days using an ESPEC GPL-2 aging box.

[0083] 5. Number average molecular weight

[0084] The number average molecular weight of the epoxy resin modified with butanediol / trimellitic anhydride was measured by GPC.

[0085] Preparation Example

[0086] Under a nitrogen atmosphere, 10 mol of 1,4-butanediol (BDO) and 20 mol of trimellitic anhydride were added to a flask with a condenser, and the raw materials were heated and stirred to completely blend and evenly blend; 1 mol of boron trifluoride ether was slowly added dropwise to the above reaction solution, the temperature was raised to 70°C, and after reacting for 2.5 hours, 20 mol of epoxy resin (Nan Ya Epoxy 128) was added, the temperature was raised to 95°C and the reaction was continued for 6 hours to obtain a butanediol / trimellitic anhydride modified epoxy resin (BDODET), and the number average molecular weight of the butanediol / trimellitic anhydride modified epoxy resin was measured to be about 2000.

[0087] Example

[0088] A certain mass of PLA, PBAT, BDODET, mineral powder, anti-blocking agent and lubricant are put into a high-speed mixer and mixed for 10 to 15 minutes, and then extruded and granulated by a twin-screw extruder at a temperature of 190 to 210° C. to obtain a biodegradable material in particle form.

[0089] By using different types and / or amounts of raw materials, the biodegradable materials of Examples 1 to 6 and Comparative Examples 1 to 2 were prepared according to the above process. The types and amounts (mass percentage) of raw materials of each example and comparative example are shown in Table 1.

[0090] Table 1 Types and amounts of raw materials in various embodiments and comparative examples

[0091]

[0092]

[0093] Application Examples

[0094] The biodegradable materials obtained in Examples 1 to 6 and Comparative Examples 1 to 2 were respectively used to prepare films according to the following process: a film blowing machine was used for film blowing at a capacity of 120 kg / h, the die diameter of the film blowing machine was 100 mm, the film blowing temperature was 160 to 165° C., the blowing ratio was 3.5, and the film thickness was 50 to 55 um.

[0095] After the films of Examples 1 to 6 and Comparative Examples 1 to 2 were placed at room temperature for 1 day (1d), a portion of the films were taken out for edge sealing at 280°C using a bag making machine, and then the puncture and edge sealing strength tests were performed. The remaining films were kept at room temperature, and the films were taken out for edge sealing at 7 days (7d), 14 days (14d), and 21 days (21d) after the film preparation was completed, and the edge sealing strength was tested, and the edge sealing tearing forms were compared by hand tearing. In addition, the initial melt index and the melt index after double 85 aging for 3 days (3d) were tested for the degradable materials obtained in Examples 1 to 6 and Comparative Examples 1 to 2. The specific results are shown in Table 2.

[0096] Table 2 Test results of material properties of various embodiments and comparative examples and corresponding film properties

[0097]

[0098]

[0099] As shown in Table 1, the main difference between Examples 1 to 6 and Comparative Examples 1 to 2 is that the raw materials of Comparative Examples 1 to 2 do not include BDODET. According to the results in Table 2, the initial melting index and the melting index after aging with double 85 of the degradable materials of Examples 1 to 6 are significantly lower than the corresponding melting index of the degradable materials of Comparative Examples 1 to 2, indicating that the introduction of BDODET can reduce the degradation rate of the material and avoid edge seal failure caused by aging.

[0100] In addition, the edge seal of the film bag of Comparative Examples 1-2 has become straight after 1 day of storage, and completely straight after 7 days of storage, and the edge seal strength has decreased significantly with the extension of the film storage time. However, the edge seal of the film of Examples 1-6 is still jagged after 21 days of storage, and the edge seal strength has only slightly decreased.

[0101] Therefore, the embodiment of the present invention can improve the edge seal strength of the prepared film and extend the edge seal timeliness by adding BDODET to the raw materials for preparing the degradable material.

[0102] Unless otherwise defined, the terms used in the present invention have the meanings commonly understood by those skilled in the art.

[0103] The embodiments described in the present invention are for illustrative purposes only and are not intended to limit the scope of protection of the present invention. Those skilled in the art may make various other substitutions, changes and improvements within the scope of the present invention. Therefore, the present invention is not limited to the above embodiments, but is only limited by the claims.

Claims

1. A composition comprising poly(butylene adipate / terephthalate), poly(lactic acid) and a butanediol / trimellitic anhydride modified epoxy resin.

2. The composition according to claim 1, comprising 65-80 wt% of the poly(butylene adipate / terephthalate), 3-8 wt% of poly(lactic acid) and 0.2-2 wt% of the butanediol / trimellitic anhydride-modified epoxy resin; and / or, The butanediol / trimellitic anhydride modified epoxy resin contains hydroxyl, carboxyl and epoxy functional groups; and / or, The number average molecular weight of the epoxy resin modified with butanediol / trimellitic anhydride is 1500 to 2500; and / or, The composition further comprises one or more of mineral powder, an opening agent and a lubricant.

3. The composition according to claim 2, comprising 70-80 wt% of the poly(butylene adipate / terephthalate), 5-7 wt% of poly(lactic acid) and 0.2-1 wt% of the butanediol / trimellitic anhydride-modified epoxy resin; and / or, The content of the mineral powder in the composition is 12 to 30 wt %; and / or, The content of the opening agent in the composition is 0.1 to 0.3 wt %; and / or, The content of the lubricant in the composition is 0.1-0.3 wt %.

4. The composition according to claim 1, in, The melt flow rate of the polylactic acid at 190° C. and 2.16 kg load is 0.2 to 30 g / 10 min; and / or, The melt flow rate of the polybutylene adipate / terephthalate at 200° C. and 2.16 kg load is 2 to 5 g / 10 min; and / or, The weight average molecular weight of the polybutylene adipate / terephthalate is 100,000 to 200,000.

5. The composition according to claim 1, in, The melt flow rate of the polylactic acid at 190° C. and 2.16 kg load is 2 to 20 g / 10 min; and / or, The butanediol / trimellitic anhydride modified epoxy resin is prepared by reacting butanediol, epoxy resin and trimellitic anhydride.

6. The composition according to claim 5, in, In the preparation of the butanediol / trimellitic anhydride modified epoxy resin, the molar ratio of the trimellitic anhydride to the butanediol is (1.9-2.1):1; and / or, the molar ratio of the trimellitic anhydride to the epoxy resin is (0.9-1.1):1; and / or, In the preparation of the butanediol / trimellitic anhydride modified epoxy resin, the butanediol and the trimellitic anhydride are first esterified, and then the epoxy resin is added to react; and / or, The butanediol is 1,4-butanediol; and / or, The epoxy equivalent of the epoxy resin is 180 to 200; and / or, The epoxy resin is a double A-type epoxy resin.

7. A degradable material obtained by mixing and reacting the components of the composition according to any one of claims 1 to 6 and then molding them.

8. Use of the composition according to any one of claims 1 to 6 or the degradable material according to claim 7 in the preparation of a degradable film.

9. A degradable film, made from the composition according to any one of claims 1 to 6 or the degradable material according to claim 7.

10. A film bag made from the degradable film according to claim 9.

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