Degradable Blister Sheet, Its Preparation Method and Blister Products

Abstract

This application relates to a degradable blister sheet, a preparation method thereof, and a blister product. The degradable blister sheet comprises the following components in percentage by weight: 30%-65% of polyhydroxyalkanoate, 10%-35% of inorganic powder, 5%-20% of poly(methyl ethylene carbonate), 1%-5% of small molecule lubricant, 0.2%-1% of nucleating agent, and 0.5%-3% of inorganic color powder; wherein, the polyhydroxyalkanoate comprises one or more of polyhydroxybutyrate, hydroxybutyrate valerate copolyester, hydroxybutyrate hexanoate copolyester, and poly(3-hydroxybutyrate-4-hydroxybutyrate) copolymer; the inorganic powder comprises one or more of talc, diatomite, kaolin, calcium carbonate, and barium sulfate. The degradable blister sheet provided by this application can be naturally degraded in nature, which is beneficial to alleviating plastic pollution and reducing the harm of plastic use to the natural environment.

Description

Technical Field

[0001] This application relates to the technical field of environmental protection plastics, and particularly to degradable plastic sheets, their preparation methods, and plastic products obtained by thermoforming using such sheets. Background Art

[0002] With the continuous and massive use of plastics, approximately 8 million tons of plastics are dumped into the ocean every year. So far, it is estimated that there are 150 million tons of plastics in the ocean. This will cause a fatal blow to the marine ecosystem. The development and application of degradable plastics are extremely urgent.

[0003] In view of this, there is an urgent need to propose a plastic sheet that can be naturally degraded in nature, relieve plastic pollution, and reduce the harm of plastic use to the natural environment. Summary of the Invention

[0004] To overcome the problems existing in the related art, this application provides a degradable plastic sheet, its preparation method, and a plastic product obtained by thermoforming using such a sheet. The degradable plastic sheet can be naturally degraded in nature, which is beneficial to relieving plastic pollution and reducing the harm of plastic use to the natural environment.

[0005] In the first aspect of this application, a degradable plastic sheet is provided, which comprises the following components in percentage by weight:

[0006] Polyhydroxyalkanoates 30%-65%, inorganic powder 10%-35%, poly(methyl ethylene carbonate) 5%-20%, small molecule lubricant 1%-5%, nucleating agent 0.2%-1%, and inorganic color powder 0.5%-3%;

[0007] Among them, the polyhydroxyalkanoates include one or more of polyhydroxybutyrate, hydroxybutyrate-valerate copolymer, hydroxybutyrate-caproate copolymer, and poly(3-hydroxybutyrate-4-hydroxybutyrate) copolymer;

[0008] The inorganic powder includes one or more of talc, diatomaceous earth, kaolin, calcium carbonate, and barium sulfate.

[0009] In one embodiment, the degradable plastic sheet comprises the following components in percentage by weight:

[0010] Polyhydroxyalkanoates 60%, inorganic powder 20%, poly(methyl ethylene carbonate) 15.5%, small molecule lubricant 3%, nucleating agent 0.5%, and inorganic color powder 1%.

[0011] In one embodiment, the polyhydroxyalkanoates are composed of polyhydroxybutyrate and poly(3-hydroxybutyrate-4-hydroxybutyrate) copolymer;

[0012] The weight ratio of polyhydroxybutyrate to poly(3-hydroxybutyrate-4-hydroxybutyrate) copolymer is 2:3.

[0013] In one embodiment, the inorganic toner is composed of diatomaceous earth and barium sulfate;

[0014] The weight ratio of diatomaceous earth to barium sulfate is 1:1.

[0015] The second aspect of the present application provides a method for preparing a degradable blister sheet for preparing the degradable blister sheet according to any one of the first aspect, including:

[0016] Weigh polyhydroxyalkanoate, inorganic powder, poly(methyl ethylene carbonate), small molecule lubricant, nucleating agent and inorganic toner;

[0017] Stir and mix polyhydroxyalkanoate, inorganic powder, poly(methyl ethylene carbonate), small molecule lubricant, nucleating agent and inorganic toner to obtain a mixed material;

[0018] Start the extruder and adjust the temperature of each zone of the extruder to the corresponding preset temperature;

[0019] Add the mixed material to the hopper of the extruder and adjust the operating parameters of the extruder so that the extruder extrudes and draws a sheet to obtain a degradable blister sheet.

[0020] In one embodiment, stirring and mixing polyhydroxyalkanoate, inorganic powder, poly(methyl ethylene carbonate), small molecule lubricant, nucleating agent and inorganic toner includes:

[0021] Add polyhydroxyalkanoate, inorganic powder, poly(methyl ethylene carbonate), small molecule lubricant, nucleating agent and inorganic toner to a high-speed mixer;

[0022] Stir polyhydroxyalkanoate, inorganic powder, poly(methyl ethylene carbonate), small molecule lubricant, nucleating agent and inorganic toner by the high-speed mixer at a rotation speed of 450 - 900 r / min for 10 min - 25 min.

[0023] In one embodiment, stirring polyhydroxyalkanoate, inorganic powder, poly(methyl ethylene carbonate), small molecule lubricant, nucleating agent and inorganic toner by the high-speed mixer at a rotation speed of 450 - 900 r / min for 10 min - 25 min includes:

[0024] Stir polyhydroxyalkanoate, inorganic powder, poly(methyl ethylene carbonate), small molecule lubricant, nucleating agent and inorganic toner by the high-speed mixer at a rotation speed of 500 r / min for 15 min.

[0025] In one embodiment, the extruder is a parallel twin-screw extruder;

[0026] Starting the extruder and adjusting the temperature of each zone of the extruder to the corresponding preset temperature includes:

[0027] Start the parallel twin-screw extruder;

[0028] Adjust the temperature of the first zone of the parallel twin-screw extruder to 120°C - 135°C;

[0029] Adjust the temperature of the second zone of the parallel twin-screw extruder to 135°C - 150°C;

[0030] Adjust the temperature of the third zone of the parallel twin-screw extruder to 150°C - 175°C;

[0031] Adjust the temperature of the fourth zone of the parallel twin-screw extruder to 150°C - 175°C;

[0032] Adjust the temperature of the fifth zone of the parallel twin-screw extruder to 150°C - 175°C;

[0033] Adjust the temperature of the sixth zone of the parallel twin-screw extruder to 150°C - 175°C;

[0034] Adjust the temperature of the seventh zone of the parallel twin-screw extruder to 150°C - 175°C;

[0035] Adjust the temperature of the eighth zone of the parallel twin-screw extruder to 150°C - 175°C;

[0036] Adjust the temperature of the ninth zone of the parallel twin-screw extruder to 175°C - 180°C.

[0037] In one embodiment, starting the extruder and adjusting the temperature of each zone of the extruder to the corresponding preset temperature includes:

[0038] Start the parallel twin-screw extruder;

[0039] Adjust the temperature of the first zone of the parallel twin-screw extruder to 130°C;

[0040] Adjust the temperature of the second zone of the parallel twin-screw extruder to 130°C;

[0041] Adjust the temperature of the third zone of the parallel twin-screw extruder to 160°C;

[0042] Adjust the temperature of the fourth zone of the parallel twin-screw extruder to 160°C;

[0043] Adjust the temperature of the fifth zone of the parallel twin-screw extruder to 160°C;

[0044] Adjust the temperature of the sixth zone of the parallel twin-screw extruder to 160°C;

[0045] Adjust the temperature of the seventh zone of the parallel twin-screw extruder to 160°C;

[0046] Adjust the temperature of the eighth zone of the parallel twin-screw extruder to 160°C;

[0047] Adjust the temperature of the nine zones of the parallel twin-screw extruder to 178 °C.

[0048] In one embodiment, the operating parameters include the feeding speed, the extrusion speed, the pressure roller speed, the winding speed, and the pressure roller gap;

[0049] Adjust the operating parameters of the extruder, including:

[0050] Adjust the feeding speed to 13 - 25 r / min;

[0051] Adjust the extrusion speed to 45 - 90 r / min;

[0052] Adjust the pressure roller speed to 5 - 25 r / min;

[0053] Adjust the winding speed to 5 - 25 r / min;

[0054] Adjust the pressure roller gap to 0.1 - 1.5 mm.

[0055] In one embodiment, adjust the operating parameters of the extruder, including:

[0056] Adjust the feeding speed to 14 r / min;

[0057] Adjust the extrusion speed to 60 r / min;

[0058] Adjust the pressure roller speed to 10 r / min;

[0059] Adjust the winding speed to 10 r / min;

[0060] Adjust the pressure roller gap to 0.15 mm.

[0061] The third aspect of the present application provides a blister product, which is a product obtained by blister processing the biodegradable blister sheet according to any one of the first aspect based on the blister process;

[0062] Among them, the blister process includes:

[0063] Bake the biodegradable blister sheet at a baking temperature of 125 °C - 145 °C for 4 s - 8 s;

[0064] Perform shaping and cooling on the baked biodegradable blister sheet, and the shaping and cooling duration is 7 s - 25 s.

[0065] The technical solution provided by the present application may include the following beneficial effects:

[0066] The degradable blister sheet provided by this application comprises the following components by weight percentage: 30%-65% of polyhydroxyalkanoate, 10%-35% of inorganic powder, 5%-20% of poly(methyl ethylene carbonate), 1%-5% of small molecule lubricant, 0.2%-1% of nucleating agent, and 0.5%-3% of inorganic color powder. It can achieve biodegradation in nature, such as in water bodies like the ocean, rivers, etc. The degraded substances are carbon dioxide and water. It is a green and environmentally friendly plastic, which is beneficial to alleviating plastic pollution and reducing the harm of plastic use to the natural environment.

[0067] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit this application. BRIEF DESCRIPTION OF THE DRAWINGS

[0068] By describing the exemplary embodiments of this application in more detail in conjunction with the drawings, the above and other objects, features, and advantages of this application will become more obvious. Among them, in the exemplary embodiments of this application, the same reference numerals generally represent the same components.

[0069] Figure 1 It is a schematic flow chart of the preparation method of the degradable blister sheet shown in the embodiments of this application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0070] The preferred embodiments of this application will be described in more detail below with reference to the drawings. Although the preferred embodiments of this application are shown in the drawings, it should be understood that this application can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to make this application more thorough and complete, and to fully convey the scope of this application to those skilled in the art.

[0071] The terms used in this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The singular forms "a", "the", and "said" used in this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0072] It should be understood that although the terms "first", "second", "third", etc. may be used in this application to describe various information, such information should not be limited to these terms. These terms are only used to distinguish information of the same type from each other. For example, without departing from the scope of this application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of this application, the meaning of "a plurality" is two or more, unless otherwise specifically defined.

[0073] With the continuous and extensive use of plastics, approximately 8 million tons of plastics are dumped into the ocean every year. So far, it is estimated that there are 150 million tons of plastics in the ocean. According to the information of the Ocean Administration, within less than 10 years in the future, it is expected that the plastics in the ocean will increase to 250 million tons, which will cause a fatal blow to the marine ecosystem. The development and application of degradable plastics are extremely urgent.

[0074] In view of this, there is an urgent need to propose a blister sheet that can be naturally degraded in nature, relieve plastic pollution, and reduce the harm of plastic use to the natural environment.

[0075] In response to the above problems, the embodiments of this application provide a degradable blister sheet that can be naturally degraded in nature, which is beneficial to relieving plastic pollution and reducing the harm of plastic use to the natural environment.

[0076] The degradable blister sheet shown in the embodiments of this application may include the following components by weight percentage: polyhydroxyalkanoate 30%-65%, inorganic powder 10%-35%, poly(ethylene carbonate) 5%-20%, small molecule lubricant 1%-5%, nucleating agent 0.2%-1%, and inorganic color powder 0.5%-3%.

[0077] The above polyhydroxyalkanoate is polyhydroxyalkanoate (PHA), which is a kind of intracellular polyester synthesized by many microorganisms and is a natural polymer biomaterial. In the embodiments of this application, the polyhydroxyalkanoate includes one or more of polyhydroxybutyrate, hydroxybutyrate-valerate copolymer, hydroxybutyrate-caproate copolymer, and poly(3-hydroxybutyrate-4-hydroxybutyrate) copolymer.

[0078] Among them, polyhydroxybutyrate is PHB. PHB is a kind of thermoplastic biodegradable material manufactured by microbial fermenters. Pure PHB is a homopolymer of 3-hydroxybutyrate, with a melting point of 175°C and high cleanliness.

[0079] Hydroxybutyrate-valerate copolyester is PHBV, which is a copolymer of 3-hydroxybutyrate and 3-hydroxyvalerate, a new biopolymer. It is a biomaterial produced by fermentation engineering technology using starch as raw material. It is a biopolyester produced by bacteria, can be digested by bacteria, and completely decomposed into carbon dioxide, water and biomass under soil or composting conditions.

[0080] Hydroxybutyric acid and hexanoic acid copolyester is PHBHHx, which is a copolyester of 3-hydroxybutyric acid and 3-hydroxyhexanoic acid and is biodegradable.

[0081] Poly 3-hydroxybutyrate-4-hydroxybutyrate copolymer is P34HB. P34HB is a copolymer of 3-hydroxybutyrate and 4-hydroxybutyrate. It is synthesized by microorganisms using biomass materials as raw materials. It has good biocompatibility and is a completely degradable polymer material that can be completely decomposed by microorganisms in the natural environment and in organisms.

[0082] In an embodiment of the present application, the inorganic powder includes one or more of talc, diatomaceous earth, kaolin, calcium carbonate and barium sulfate.

[0083] Polymethyl ethylene carbonate refers to PPC plastic, which is a completely biodegradable and environmentally friendly plastic synthesized from carbon dioxide and propylene oxide.

[0084] The small molecule lubricant may be, for example, a small molecule amide lubricant, such as erucic acid amide, oleic acid amide, etc. The small molecule lubricant can improve the lubricity of the degradable blister sheet and can give the degradable blister sheet excellent scratch resistance.

[0085] Nucleating agent refers to a functional chemical additive that can change part of the crystallization behavior, improve the transparency, rigidity, surface gloss, impact toughness and heat deformation temperature of the sheet, shorten the sheet forming cycle, and improve the processing and application performance of the sheet.

[0086] Inorganic pigments are pigments made from natural minerals or inorganic compounds. Inorganic pigments are pure natural processing materials with natural and environmentally friendly characteristics. Inorganic pigments have environmental protection effects that organic pigments cannot match, and they will not volatilize or produce substances that are harmful to the human body during use.

[0087] In some embodiments, the degradable blister sheet may comprise the following components by weight percentage: polyhydroxyalkanoate 60%, inorganic powder 20%, poly(methyl ethylene carbonate) 15.5%, small molecule lubricant 3%, nucleating agent 0.5%, and inorganic color powder 1%. Among them, the polyhydroxyalkanoate is composed of polyhydroxybutyrate and poly(3-hydroxybutyrate-4-hydroxybutyrate) copolymer, and the weight ratio of polyhydroxybutyrate to poly(3-hydroxybutyrate-4-hydroxybutyrate) copolymer is 2:3. The inorganic color powder is composed of diatomaceous earth and barium sulfate, and the weight ratio of diatomaceous earth to barium sulfate is 1:1.

[0088] Corresponding to the foregoing embodiments of the degradable blister sheet, the present application also provides a method for preparing a degradable blister sheet and corresponding embodiments. Figure 1 is a schematic flow chart of the method for preparing a degradable blister sheet shown in the embodiments of the present application. Please refer to Figure 1 , the method for preparing a degradable blister sheet shown in the embodiments of the present application may include:

[0089] In step 101, weigh polyhydroxyalkanoate, inorganic powder, poly(methyl ethylene carbonate), small molecule lubricant, nucleating agent, and inorganic color powder.

[0090] Weigh 30%-65% of polyhydroxyalkanoate, 10%-35% of inorganic powder, 5%-20% of poly(methyl ethylene carbonate), 1%-5% of small molecule lubricant, 0.2%-1% of nucleating agent, and 0.5%-3% of inorganic color powder. Preferably, in some embodiments, 60% of polyhydroxyalkanoate, 20% of inorganic powder, 15.5% of poly(methyl ethylene carbonate), 3% of small molecule lubricant, 0.5% of nucleating agent, and 1% of inorganic color powder may be weighed. Among them, the polyhydroxyalkanoate is composed of polyhydroxybutyrate and poly(3-hydroxybutyrate-4-hydroxybutyrate) copolymer, and the weight ratio of polyhydroxybutyrate to poly(3-hydroxybutyrate-4-hydroxybutyrate) copolymer is 2:3. The inorganic color powder is composed of diatomaceous earth and barium sulfate, and the weight ratio of diatomaceous earth to barium sulfate is 1:1.

[0091] In step 102, stir and mix polyhydroxyalkanoate, inorganic powder, poly(methyl ethylene carbonate), small molecule lubricant, nucleating agent, and inorganic color powder to obtain a mixed material. Specifically, in the embodiments of the present application, polyhydroxyalkanoate, inorganic powder, poly(methyl ethylene carbonate), small molecule lubricant, nucleating agent, and inorganic color powder may be added to a high-speed mixer, and then the polyhydroxyalkanoate, inorganic powder, poly(methyl ethylene carbonate), small molecule lubricant, nucleating agent, and inorganic color powder are stirred for 10 min - 25 min at a rotation speed of 450 - 900 r / min by the high-speed mixer.

[0092] Specifically, when 60% of polyhydroxyalkanoate, 20% of inorganic powder, 15.5% of poly(ethylene carbonate), 3% of small molecule lubricant, 0.5% of nucleating agent, and 1% of inorganic color powder are weighed, the polyhydroxyalkanoate, inorganic powder, poly(ethylene carbonate), small molecule lubricant, nucleating agent, and inorganic color powder can be stirred for 15 min at a rotational speed of 500 r / min by a high-speed mixer. It can be understood that in practical applications, the stirring speed and stirring duration can be adjusted according to the actual application situation, and there is no unique limitation here.

[0093] In step 103, start the extruder and adjust the temperatures of the respective zones of the extruder to the corresponding preset temperatures. In the embodiments of the present application, the extruder can be a parallel twin-screw extruder, which is widely used in the filling, blending, modification, reinforcement of rubber and plastics and engineering resins, the devolatilization treatment of chlorinated polypropylene and superabsorbent resins, the extrusion of degradable masterbatch, polyamide polycondensation, and polyurethane polyaddition reactions; the granulation of carbon powder and magnetic powder, the preparation of insulating materials, sheath materials, low-smoke and low-halogen flame-retardant PVC cable materials, and various silane cross-linked materials for cables, etc.

[0094] Specifically, the parallel twin-screw extruder can be started first. Further, the temperature of zone 1 of the parallel twin-screw extruder is adjusted to 120°C - 135°C; the temperature of zone 2 of the parallel twin-screw extruder is adjusted to 135°C - 150°C; the temperature of zone 3 of the parallel twin-screw extruder is adjusted to 150°C - 175°C; the temperature of zone 4 of the parallel twin-screw extruder is adjusted to 150°C - 175°C; the temperature of zone 5 of the parallel twin-screw extruder is adjusted to 150°C - 175°C; the temperature of zone 6 of the parallel twin-screw extruder is adjusted to 150°C - 175°C; the temperature of zone 7 of the parallel twin-screw extruder is adjusted to 150°C - 175°C; the temperature of zone 8 of the parallel twin-screw extruder is adjusted to 150°C - 175°C; the temperature of zone 9 of the parallel twin-screw extruder is adjusted to 175°C - 180°C.

[0095] Specifically, when 60% of polyhydroxyalkanoate, 20% of inorganic powder, 15.5% of poly(ethylene carbonate), 3% of small molecule lubricant, 0.5% of nucleating agent, and 1% of inorganic color powder are weighed, the temperature of zone 1 of the parallel twin-screw extruder can be adjusted to 130°C; the temperature of zone 2 of the parallel twin-screw extruder is adjusted to 130°C; the temperature of zone 3 of the parallel twin-screw extruder is adjusted to 160°C; the temperature of zone 4 of the parallel twin-screw extruder is adjusted to 160°C; the temperature of zone 5 of the parallel twin-screw extruder is adjusted to 160°C; the temperature of zone 6 of the parallel twin-screw extruder is adjusted to 160°C; the temperature of zone 7 of the parallel twin-screw extruder is adjusted to 160°C; the temperature of zone 8 of the parallel twin-screw extruder is adjusted to 160°C; the temperature of zone 9 of the parallel twin-screw extruder is adjusted to 178°C.

[0096] It can be understood that in practical applications, the temperatures of the first to ninth zones of the parallel twin-screw extruder can be adjusted according to the actual application situation, and there is no unique limitation here.

[0097] In step 104, the mixed material is added to the hopper of the extruder and the operating parameters of the extruder are adjusted so that the extruder extrudes a sheet to obtain a degradable thermoformed sheet. In the embodiments of the present application, the above operating parameters may include but are not limited to the feeding speed, the extrusion speed, the pressure roller speed, the winding speed, and the pressure roller gap.

[0098] Adjusting the operating parameters of the extruder may specifically be to adjust the feeding speed to 13 - 25 r / min; adjust the extrusion speed to 45 - 90 r / min; adjust the pressure roller speed to 5 - 25 r / min; adjust the winding speed to 5 - 25 r / min; and adjust the pressure roller gap to 0.1 - 1.5 mm.

[0099] Specifically, when 60% of polyhydroxyalkanoate, 20% of inorganic powder, 15.5% of poly(methyl ethylene carbonate), 3% of small molecule lubricant, 0.5% of nucleating agent, and 1% of inorganic color powder are weighed, the feeding speed can be adjusted to 14 r / min; the extrusion speed can be adjusted to 60 r / min; the pressure roller speed can be adjusted to 10 r / min; the winding speed can be adjusted to 10 r / min; and the pressure roller gap can be adjusted to 0.15 mm.

[0100] In the embodiments of the present application, after testing, the physical properties of the prepared degradable thermoformed sheet can be as shown in Table 1 below:

[0101] Table 1:

[0102] Test content Test method Test value Test unit Density ASTM-D1283 1.3-1.5 <![CDATA[g / cm 3 > Melt index ASTM-D792 3-6 g / 10min Elongation at break ASTM-D1708 45-135 ％ Tensile yield strength ASTM-D1708 9-17 Mpa Tensile modulus ASTM-D1708 2700-4500 Heat distortion temperature 70-90 ℃

[0103] Among them, ASTM-D1283, ASTM-D792, and ASTM-D1708 are all standard methods for testing the properties of polymer materials.

[0104] In particular, when 60% of polyhydroxyalkanoate, 20% of inorganic powder, 15.5% of poly(methyl ethylene carbonate), 3% of small molecule lubricant, 0.5% of nucleating agent, and 1% of inorganic color powder are weighed, among which, the polyhydroxyalkanoate is composed of polyhydroxybutyrate and poly(3-hydroxybutyrate-4-hydroxybutyrate) copolymer, and the weight ratio of polyhydroxybutyrate to poly(3-hydroxybutyrate-4-hydroxybutyrate) copolymer is 2:3, the inorganic color powder is composed of diatomite and barium sulfate, and the weight ratio of diatomite to barium sulfate is 1:1; then, the polyhydroxyalkanoate, inorganic powder, poly(methyl ethylene carbonate), small molecule lubricant, nucleating agent, and inorganic color powder are stirred at a speed of 500 r / min by a high-speed mixer for 15 min; then, the temperature of the first zone of the parallel twin-screw extruder is adjusted to 130 °C; the temperature of the second zone of the parallel twin-screw extruder is adjusted to 130 °C; the temperature of the third zone of the parallel twin-screw extruder is adjusted to 160 °C; the temperature of the fourth zone of the parallel twin-screw extruder is adjusted to 160 °C; the temperature of the fifth zone of the parallel twin-screw extruder is adjusted to 160 °C; the temperature of the sixth zone of the parallel twin-screw extruder is adjusted to 160 °C; the temperature of the seventh zone of the parallel twin-screw extruder is adjusted to 160 °C; the temperature of the eighth zone of the parallel twin-screw extruder is adjusted to 160 °C; the temperature of the ninth zone of the parallel twin-screw extruder is adjusted to 178 °C; finally, the feeding speed is adjusted to 14 r / min; the extrusion speed is adjusted to 60 r / min; the pressure roller speed is adjusted to 10 r / min; the winding speed is adjusted to 10 r / min; the pressure roller gap is adjusted to 0.15 mm, so that the extruder extrudes and draws a sheet to obtain a degradable thermoformed sheet. The physical properties of the degradable thermoformed sheet obtained in this case can be as shown in Table 2 below:

[0105] Table 2:

[0106] Test content Test method Test value Test unit Density ASTM-D1283 1.32 <![CDATA[g / cm 3 > Melt index ASTM-D792 4 g / 10min Elongation at break ASTM-D1708 55 ％ Tensile yield strength ASTM-D1708 11 Mpa Tensile modulus ASTM-D1708 3700 Heat distortion temperature 85 ℃

[0107] Corresponding to the foregoing embodiments of the degradable thermoformed sheet, the present application further provides a thermoformed product, which is a product obtained by thermoforming the degradable thermoformed sheet based on a thermoforming process. Among them, the above thermoforming process may specifically include: baking the degradable thermoformed sheet at a baking temperature of 125 °C - 145 °C for 4 s - 8 s; performing shaping and cooling on the baked degradable thermoformed sheet, and the shaping and cooling duration is 7 s - 25 s.

[0108] In some embodiments, preferably, the degradable thermoformed sheet can be baked at a baking temperature of 135 °C for 4 s; perform shaping and cooling on the baked degradable thermoformed sheet, and the shaping and cooling duration is 12 s. It can be understood that in actual applications, the baking temperature, baking time, and shaping and cooling duration need to be determined according to the actual application situation, and there is no unique limitation here.

[0109] After testing, the marine degradation test results of the above-mentioned plastic blister products can be shown in Table 3 below:

[0110] Table 3:

[0111] Serial number Product thickness Degradation condition Degradation time 1 0.1mm Marine environment 40 - 52 weeks 2 0.2mm Marine environment 60 - 75 weeks 3 0.3mm Marine environment 70 - 95 weeks 4 0.15mm Marine environment 55 weeks

[0112] Among them, the product thickness is determined by the length of the pressure roller gap.

[0113] The degradable plastic blister sheet provided by this application includes the following components by weight percentage: polyhydroxyalkanoate 30%-65%, inorganic powder 10%-35%, poly(methyl ethylene carbonate) 5%-20%, small molecule lubricant 1%-5%, nucleating agent 0.2%-1% and inorganic color powder 0.5%-3%. After experimental testing, compared with the traditional PLA plastic blister sheet, the heat distortion temperature of the degradable plastic blister sheet prepared by this application is 60%-80% higher than that of the traditional PLA plastic blister sheet (58°C), and the elongation at break of the degradable plastic blister sheet is higher than that of the traditional PLA plastic blister sheet (4%-15%), which can meet the application scenarios such as disposable food packaging products and electronic product packaging products with higher toughness requirements. Moreover, the degradable plastic blister sheet can be biodegradable in nature, such as in water bodies such as the ocean and rivers, and the degraded substances are carbon dioxide and water. It is a green and environmentally friendly plastic, which is conducive to alleviating plastic pollution and reducing the harm of plastic use to the natural environment.

[0114] The solution of this application has been described in detail above with reference to the accompanying drawings. In the above embodiments, the descriptions of each embodiment have their own emphases. For the parts not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments. Those skilled in the art should also know that the actions and modules involved in the specification are not necessarily essential to this application. In addition, it can be understood that the steps in the method embodiments of this application can be adjusted, combined and deleted according to actual needs, and the modules in the device embodiments of this application can be combined, divided and deleted according to actual needs.

[0115] The above has described the embodiments of this application. The above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes are obvious to those of ordinary skill in the art in the technical field without departing from the scope and spirit of the described embodiments. The selection of the terms used herein is intended to best explain the principles of the embodiments, practical applications or improvements to the technologies in the market, or to enable other ordinary technicians in the technical field to understand the embodiments disclosed herein.

Claims

1. A degradable blister sheet, characterized in that, Comprising the following components by weight percentage: Polyhydroxyalkanoate 30%-65%, inorganic powder 10%-35%, poly(ethylene carbonate) 5%-20%, small molecule lubricant 1%-5%, nucleating agent 0.2%-1% and inorganic color powder 0.5%-3%; Wherein, the polyhydroxyalkanoate comprises one or more of polyhydroxybutyrate, hydroxybutyrate valerate copolyester, hydroxybutyrate hexanoate copolyester and poly(3-hydroxybutyrate-4-hydroxybutyrate) copolymer; The degradable blister sheet comprises the following components by weight percentage: Polyhydroxyalkanoate 60%, inorganic powder 20%, poly(ethylene carbonate) 15.5%, small molecule lubricant 3%, nucleating agent 0.5%, inorganic color powder 1%; The polyhydroxyalkanoate is composed of the polyhydroxybutyrate and the poly(3-hydroxybutyrate-4-hydroxybutyrate) copolymer; The weight ratio of the polyhydroxybutyrate to the poly(3-hydroxybutyrate-4-hydroxybutyrate) copolymer is 2:3; The inorganic powder comprises one or more of talc, diatomite, kaolin, calcium carbonate and barium sulfate; The inorganic color powder is composed of the diatomite and the barium sulfate; The weight ratio of the diatomite to the barium sulfate is 1:

1.

2. A preparation method of a degradable plastic sheet, characterized in that, For preparing the degradable blister sheet according to any one of claims 1, comprising: Weighing polyhydroxyalkanoate, inorganic powder, poly(ethylene carbonate), small molecule lubricant, nucleating agent and inorganic color powder; Stirring and mixing the polyhydroxyalkanoate, the inorganic powder, the poly(ethylene carbonate), the small molecule lubricant, the nucleating agent and the inorganic color powder to obtain a mixed material; Starting the extruder and adjusting the temperatures of each zone of the extruder to the corresponding preset temperatures respectively; Adding the mixed material into the hopper of the extruder and adjusting the operating parameters of the extruder so that the extruder extrudes and draws a sheet to obtain the degradable blister sheet.

3. The method for preparing a degradable blister sheet according to claim 2, wherein The stirring and mixing of the polyhydroxyalkanoate, the inorganic powder, the poly(ethylene carbonate), the small molecule lubricant, the nucleating agent and the inorganic color powder comprises: Adding the polyhydroxyalkanoate, the inorganic powder, the poly(ethylene carbonate), the small molecule lubricant, the nucleating agent and the inorganic color powder into a high-speed mixer; Stirring the polyhydroxyalkanoate, the inorganic powder, the poly(ethylene carbonate), the small molecule lubricant, the nucleating agent and the inorganic color powder by the high-speed mixer at a rotation speed of 450-900 r / min for 10 min-25 min.

4. The method for preparing a degradable blister sheet according to claim 3, wherein The stirring of the polyhydroxyalkanoate, the inorganic powder, the poly(ethylene carbonate), the small molecule lubricant, the nucleating agent and the inorganic color powder by the high-speed mixer at a rotation speed of 450-900 r / min for 10 min-25 min comprises: Stir the polyhydroxyalkanoate, the inorganic powder, the poly(ethylene carbonate), the small molecule lubricant, the nucleating agent and the inorganic color powder at a speed of 500 r / min for 15 min by means of the high-speed stirrer.

5. The preparation method of the degradable blister sheet according to claim 2, characterized in that, The extruder is a parallel twin-screw extruder; Starting the extruder and adjusting the temperatures of the respective zones of the extruder to corresponding preset temperatures includes: Starting the parallel twin-screw extruder; Adjusting the temperature of the first zone of the parallel twin-screw extruder to 120°C - 135°C; Adjusting the temperature of the second zone of the parallel twin-screw extruder to 135°C - 150°C; Adjusting the temperature of the third zone of the parallel twin-screw extruder to 150°C - 175°C; Adjusting the temperature of the fourth zone of the parallel twin-screw extruder to 150°C - 175°C; Adjusting the temperature of the fifth zone of the parallel twin-screw extruder to 150°C - 175°C; Adjusting the temperature of the sixth zone of the parallel twin-screw extruder to 150°C - 175°C; Adjusting the temperature of the seventh zone of the parallel twin-screw extruder to 150°C - 175°C; Adjusting the temperature of the eighth zone of the parallel twin-screw extruder to 150°C - 175°C; Adjusting the temperature of the ninth zone of the parallel twin-screw extruder to 175°C - 180°C.

6. The method for preparing a degradable blister sheet according to claim 5, wherein Starting the extruder and adjusting the temperatures of the respective zones of the extruder to corresponding preset temperatures includes: Starting the parallel twin-screw extruder; Adjusting the temperature of the first zone of the parallel twin-screw extruder to 130°C; Adjusting the temperature of the second zone of the parallel twin-screw extruder to 130°C; Adjusting the temperature of the third zone of the parallel twin-screw extruder to 160°C; Adjusting the temperature of the fourth zone of the parallel twin-screw extruder to 160°C; Adjusting the temperature of the fifth zone of the parallel twin-screw extruder to 160°C; Adjusting the temperature of the sixth zone of the parallel twin-screw extruder to 160°C; Adjusting the temperature of the seventh zone of the parallel twin-screw extruder to 160°C; Adjusting the temperature of the eighth zone of the parallel twin-screw extruder to 160°C; Adjusting the temperature of the ninth zone of the parallel twin-screw extruder to 178°C.

7. The preparation method of the degradable plastic sheet according to claim 2, characterized in that, The operating parameters include the feeding speed, the extrusion speed, the pressure roller speed, the winding speed and the pressure roller gap; Adjusting the operating parameters of the extruder includes: Adjusting the feeding speed to 13 - 25 r / min; Adjusting the extrusion speed to 45 - 90 r / min; Adjusting the pressure roller speed to 5 - 25 r / min; Adjusting the winding speed to 5 - 25 r / min; Adjusting the pressure roller gap to 0.1 - 1.5 mm.

8. The method for preparing a degradable blister sheet according to claim 7, wherein Adjusting the operating parameters of the extruder includes: Adjusting the feeding speed to 14 r / min; Adjusting the extrusion speed to 60 r / min; Adjusting the pressure roller speed to 10 r / min; Adjusting the winding speed to 10 r / min; Adjusting the pressure roller gap to 0.15 mm.

9. A blister product, characterized in that, The blister product is a product obtained by blister processing the degradable blister sheet as described in any one of claims 1 based on the blister process; Among them, the blister process includes: Baking the degradable blister sheet at a baking temperature of 125°C - 145°C for 4s - 8s; Performing shaping and cooling on the baked degradable blister sheet, and the shaping and cooling duration is 7s - 25s.

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