Raw material composition for thermoplastic products containing microalgae, the product itself, and method of manufacture.

Abstract

[Solution] A raw material composition for a thermoplastic product mixed with microalgae, the product itself, and a method for producing it, wherein the composition comprises polyvinyl alcohol, microalgae, a compatibilizer, a plasticizer, a crosslinking agent, a reaction aid, and a lubricant, wherein the weight percentage of microalgae relative to the weight of polyvinyl alcohol is between 10% and 30%, the weight percentage of the compatibilizer relative to the weight of polyvinyl alcohol is between 2% and 5%, the weight percentage of the plasticizer relative to the weight of polyvinyl alcohol is between 20% and 30%, the weight percentage of the crosslinking agent relative to the weight of polyvinyl alcohol is between 0% and 1.5%, the weight percentage of the reaction aid relative to the weight of polyvinyl alcohol is between 1% and 5%, and the weight percentage of the lubricant relative to the weight of polyvinyl alcohol is between 0.1% and 0.5%.

Description

Technical Field

[0001] The present invention relates to a raw material composition of a thermoplastic product mixed with microalgae, and particularly relates to a raw material composition of a thermoplastic product mixed with microalgae, the product, and a manufacturing method thereof.

Background Art

[0002] Reduction or elimination of plastic waste is both a global desire and a global issue, and the use of biodegradable plastics is one of the main solutions. Among biodegradable plastics, oxo-degradable plastics require decomposition conditions, so there is a lack of evidence regarding the consistency of the decomposition rate in the environment, and recently, they are being prohibited by public institutions including the European Union. At the same time, plastics derived from natural resources such as starch-based composites are expected to have a wide range of applications, but may lead to competition over food sources. Therefore, developing functional bioplastics and composites that can satisfy biodegradability, water solubility, good mechanical properties, and thermal properties has become an important issue.

[0003] The raw material of biodegradable plastics has a very high content of algae, and it has advantages such as a high production rate, easy cultivation, and little impact on the food chain, so it is suitable for use as a polymer filler in plastic production.

Summary of the Invention

[0004] The present invention aims to provide a raw material composition for thermoplastic products mixed with microalgae, the composition comprising polyvinyl alcohol, microalgae, a compatibilizer, a plasticizer, a crosslinking agent, a reaction aid, and a lubricant, wherein the weight percentage of the microalgae relative to the weight of the polyvinyl alcohol is between 10% and 30%, the weight percentage of the compatibilizer relative to the weight of the polyvinyl alcohol is between 2% and 5%, the weight percentage of the plasticizer relative to the weight of the polyvinyl alcohol is between 20% and 30%, the weight percentage of the crosslinking agent relative to the weight of the polyvinyl alcohol is between 0% and 1.5%, the weight percentage of the reaction aid relative to the weight of the polyvinyl alcohol is between 1% and 5%, and the weight percentage of the lubricant relative to the weight of the polyvinyl alcohol is between 0.1% and 0.5%.

[0005] According to one embodiment, the present invention also provides a thermoplastic product mixed with microalgae, manufactured from the above-mentioned raw material composition.

[0006] According to one embodiment, the present invention further comprises the step of mixing polyvinyl alcohol, microalgae, a compatibilizer, a plasticizer, a crosslinking agent, a reaction aid, and a lubricant to obtain a mixture, wherein the weight percentage of the microalgae based on the weight of the polyvinyl alcohol is between 10% and 30%, the weight percentage of the compatibilizer based on the weight of the polyvinyl alcohol is between 2% and 5%, and the weight percentage of the plasticizer based on the weight of the polyvinyl alcohol is between 20% and 30%. A method for producing a thermoplastic product mixed with microalgae is provided, comprising the steps of: setting the weight percentage of the crosslinking agent based on the weight of the alcohol to be between 0% and 1.5%, setting the weight percentage of the reaction aid based on the weight of the polyvinyl alcohol to be between 1% and 5%, and setting the weight percentage of the lubricant based on the weight of the polyvinyl alcohol to be between 0.1% and 0.5%; drying the mixture; making pellets from the mixture; and molding the pellets into a product. [Brief explanation of the drawing]

[0007] [Figure 1] This is a flowchart of one embodiment of the present invention. [Modes for carrying out the invention]

[0008] In this specification, some embodiments perform the steps in a specific order, but these steps can also be performed in a different, reasonable order. Some of the features described below can be replaced or eliminated by the embodiments or examples. Some additional operations can be performed before, during, or after the methods described, and it should be understood that some operations can be replaced or omitted in other embodiments of the methods.

[0009] Unless otherwise specified, all numerical values ​​relating to size, number, and physical properties described herein and in the claims should be understood to be modified in all cases with the term “approximately.” Therefore, unless otherwise stated, all numerical parameters described herein and in the claims are approximations, and a person skilled in the art can modify these approximations as appropriate to obtain desired properties using the information disclosed herein. Where numerical ranges are given at endpoints, this includes all numerical values ​​within that range and any range within that range; for example, 1 to 5 includes numerical values ​​such as 1, 1.2, 1.5, 1.7, 2, 2.75, 3, 3.80, 4, and 5.

[0010] The present invention discloses a raw material composition for a thermoplastic product mixed with microalgae, wherein protein-rich microalgae are mainly used as fillers, and the raw material composition further comprises a water-soluble additive containing polyvinyl alcohol, the additive being soluble in cold or hot water. In one example, the raw material composition comprises polyvinyl alcohol, microalgae, a compatibilizer, a plasticizer, a cross-linking agent, a processing aid, and a slipping agent. In another example, the raw material composition may selectively contain a reinforcing agent.

[0011] Looking at the ratios, the weight percentage of the microalgae relative to the weight of the polyvinyl alcohol is between 10% and 30%, the weight percentage of the compatibilizer relative to the weight of the polyvinyl alcohol is between 2% and 5%, the weight percentage of the plasticizer relative to the weight of the polyvinyl alcohol is between 20% and 30%, the weight percentage of the crosslinking agent relative to the weight of the polyvinyl alcohol is between 0% and 1.5%, the weight percentage of the reaction aid relative to the weight of the polyvinyl alcohol is between 1% and 5%, the weight percentage of the lubricant relative to the weight of the polyvinyl alcohol is between 0.1% and 0.5%, and the weight percentage of the reinforcing agent relative to the weight of the polyvinyl alcohol is between 0.2% and 0.5%.

[0012] For example, the weight percentage of the microalgae relative to the weight of the polyvinyl alcohol is 10%±0.5%, 12%±0.5%, 15%±0.5%, or 18%±0.5%, the weight percentage of the compatibilizer relative to the weight of the polyvinyl alcohol is 2%±0.5%, 3%±0.5%, 4%±0.5%, or 5%±0.5%, the weight percentage of the plasticizer relative to the weight of the polyvinyl alcohol is 16%±0.5%, 20%±0.5%, 24%±0.5%, or 25%±0.5%, and the weight percentage of the crosslinking agent crosslinking agent relative to the weight of the polyvinyl alcohol is 16%±0.5%, 20%±0.5%, 24%±0.5%, or 25%±0.5%, and the weight percentage of the crosslinking The percentages are 0% (i.e., no crosslinking agent is added), 0.2%±0.1%, 0.3%±0.1%, or 0.5%±0.1%; the weight percentage of the reaction aid relative to the weight of the polyvinyl alcohol is 3.4%±0.5%, 3.6%±0.5%, 4%±0.5%, or 5%±0.5%; the weight percentage of the lubricant relative to the weight of the polyvinyl alcohol is 0.2%±0.1%, 0.3%±0.1%, or 0.4%±0.1%; and the weight percentage of the reinforcing agent relative to the weight of the polyvinyl alcohol is 0.2±0.1% or 0.4±0.1%.

[0013] For the microalgae, those rich in protein were selected, with a protein content of at least 30%, such as Spirulina sp., Chlorella sp., Nannochloropsis sp., Dunaliella sp., Tetraselmis sp., or combinations thereof.

[0014] In terms of properties, for example, the degree of polymerization of the polyvinyl alcohol is between 300 and 2400. When the degree of polymerization is low, both the melting point and melt viscosity are low, the Young's modulus and tensile strength of the final product are low, and the elongation at break is high. When the degree of polymerization is high, both the melting point and melt viscosity are high, the Young's modulus and tensile strength of the final product are high, but the elongation at break is low. Therefore, it is necessary to keep the degree of polymerization of the polyvinyl alcohol within an appropriate range.

[0015] The hydrolysis rate of the polyvinyl alcohol in question is between 88% and 99%. For example, polyvinyl alcohol with a hydrolysis rate of 88% and model numbers PVA-0588, PVA-1788, PVA-2088, PVA-2288, or PVA-2488 can be used, or polyvinyl alcohol with a hydrolysis rate of 99% and model numbers PVA-0599, PVA-1799, PVA-2099, PVA-2299, or PVA-2499 can be used. If the hydrolysis rate of the polyvinyl alcohol is high, for example 99%, the final product will not dissolve unless the water is at a relatively high temperature (approximately 50°C), but it will have good heat resistance during use. If the hydrolysis rate of the polyvinyl alcohol is very low, for example 88%, the final product will dissolve even in water at room temperature, but it will have poor heat resistance during use. Therefore, it is necessary to keep the hydrolysis rate of the polyvinyl alcohol within an appropriate range.

[0016] Because the melting point of polyvinyl alcohol is close to its decomposition temperature, heat treatment of polyvinyl alcohol is generally difficult. Therefore, it is necessary to add plasticizers as appropriate to expand the process window, which can also improve the processability and flexibility of the product. As such plasticizers, polyols, such as glycerol, polyethylene glycol, sorbitol, xylitol, and mannitol can be used. In some cases, low molecular weight polyols can be selected, as they have good permeability and are advantageous for filling gaps between molecular chains.

[0017] To promote compatibility and melt-mixing between polyvinyl alcohol and microalgae, it is necessary to add a compatibilizer. As the compatibilizer, a natural material such as gum rosin can be selected to improve interfacial adhesion between polyvinyl alcohol and microalgae, thereby giving the product better mechanical and thermal properties.

[0018] As the crosslinking agent, one having multiple functional groups that can react with polyvinyl alcohol and microalgae, such as boric acid, citric acid, adipic acid, succinic acid, or suberic acid, can be selected. As the reaction aid, a lubricant, such as stearic acid and / or polyethylene oxide, or an internal lubricant such as myristic acid, palmitic acid, or stearic acid, or an external lubricant such as polyethylene oxide, can be used. The lubricant is, for example, an alkali metal salt of stearic acid, such as sodium stearate or potassium stearate.

[0019] Depending on the example, each component of the raw material composition may be one type or multiple types. For example, the polyvinyl alcohol may be selected as a single type or as a combination of two or more types, for example, a combination of PVA-0588 and PVA-1788, or a combination of PVA-0599 and PVA-1799. The microalgae may be selected as a single genus or as a combination of two or more genera, for example, a combination of Spirulina and Nannochloropsis. Similarly, the compatibilizer, plasticizer, crosslinking agent, reaction aid and lubricant may be selected as a single type or as a combination of two or more types.

[0020] Figure 1 is a flowchart of a manufacturing method according to one embodiment of the present invention, which includes the steps of: first, step S1 of mixing polyvinyl alcohol, microalgae, a compatibilizer, a plasticizer, a crosslinking agent, a reaction aid, and a lubricant to obtain a mixture, wherein the ratio of the raw material composition is as described above; then, step S2 of drying the mixture; next, step S3 of making pellets from the mixture; and finally, step S4 of molding the pellets into a product. In one example, the reinforcing agent may be further added to the mixture.

[0021] The present invention will be described more specifically below with reference to experimental examples; however, the experimental examples of the present invention are not limited to the following and may be modified as appropriate.

[0022] Table 1 shows the raw materials and ratios used in Experimental Examples 1-6, and Table 2 shows the raw materials and ratios used in Experimental Examples 7-12.

[0023] In Experimental Examples 1-8, these raw materials were first mixed in a mixer at a rotational speed of 300 rpm for approximately 3 minutes, and then mixed again at a rotational speed of 800 rpm for approximately 5 minutes to obtain a mixture. This mixture was then dried at a temperature of 55°C for approximately 24 hours. Pelletization was performed on the dried mixture using an extrusion pelletizing machine, and then plastic film was produced using an inflation film molding machine.

[0024] In Experimental Example 1, the temperature profile of the extrusion process from Zone 1 to the die head was 165°C, 165°C, 180°C, 185°C, 190°C, 185°C, 180°C, 170°C, and 165°C. The temperature profile of the inflation film forming process from Zone 1 to the die head was 185°C, 193°C, 205°C, 205°C, and 185°C.

[0025] In Experimental Example 2, the temperature profile of the extrusion process from Zone 1 to the die head was 175°C, 175°C, 190°C, 195°C, 200°C, 195°C, 190°C, 180°C, and 175°C, while the temperature profile of the inflation film forming process from Zone 1 to the die head was 195°C, 203°C, 215°C, 215°C, and 195°C.

[0026] In Experimental Example 3, the temperature profile of the extrusion process from Zone 1 to the die head was in the order of 175°C, 175°C, 190°C, 195°C, 200°C, 195°C, 190°C, 180°C, 175°C, and the temperature profile of the inflation film forming process from Zone 1 to the die head was in the order of 190°C, 198°C, 210°C, 210°C, 190°C.

[0027] In Experimental Example 4, the temperature profile of the extrusion process from Zone 1 to the die head was in the order of 185°C, 185°C, 200°C, 205°C, 210°C, 205°C, 200°C, 190°C, 185°C, and the temperature profile of the inflation film forming process from Zone 1 to the die head was in the order of 195°C, 203°C, 215°C, 215°C, 195°C.

[0028] In Experimental Examples 5 to 7, the temperature profile of the extrusion process from Zone 1 to the die head was in the order of 165°C, 165°C, 180°C, 185°C, 190°C, 185°C, 180°C, 170°C, 165°C, and the temperature profile of the inflation film forming process from Zone 1 to the die head was in the order of 185°C, 193°C, 205°C, 205°C, 185°C.

[0029] In Experimental Example 8, the temperature profile of the extrusion process from Zone 1 to the die head was in the order of 175°C, 185°C, 200°C, 205°C, 210°C, 205°C, 200°C, 190°C, 185°C, and the temperature profile of the inflation film forming process from Zone 1 to the die head was in the order of 185°C, 193°C, 205°C, 205°C, 185°C.

[0030] In Experimental Examples 9-12, these raw materials were first mixed in a mixer at a rotation speed of 300 rpm for about 5 minutes, and then mixed again at a rotation speed of 800 rpm for about 3 minutes to obtain a mixture. This mixture was then dried at a temperature of 55°C for about 24 hours. Pellet was produced from the dried mixture using a twin-screw extruder, and then dumbbell-shaped plastic products were manufactured using an injection molding machine (BOY 22M).

[0031] In Experimental Example 9, the temperature profile for the extrusion process from Zone 1 to the die head was 165°C, 165°C, 180°C, 185°C, 190°C, 185°C, 180°C, 170°C, and 165°C. The temperature profile for the injection molding process from Zone 1 to Zone 3 was 165°C, 175°C, and 175°C. The nozzle temperature was 170°C, the holding pressure was set to 30-40-50 (bar), and the back pressure was set to 40-60 (bar).

[0032] In Experimental Example 10, the temperature profile for the extrusion process from Zone 1 to the die head was 175°C, 175°C, 190°C, 195°C, 200°C, 195°C, 190°C, 180°C, and 175°C. The temperature profile for the injection molding process from Zone 1 to Zone 3 was 185°C, 195°C, and 195°C. The nozzle temperature was 190°C, the holding pressure was set to 65-75-85 (bar), and the back pressure was set to 80-100 (bar).

[0033] In Experiment Example 11, the temperature profile for the extrusion process from Zone 1 to the die head was 175°C, 175°C, 190°C, 195°C, 200°C, 195°C, 190°C, 180°C, and 175°C. The temperature profile for the injection molding process from Zone 1 to Zone 3 was 185°C, 195°C, and 195°C. The nozzle temperature was 190°C, the holding pressure was set to 30-40-50 (bar), and the back pressure was set to 40-60 (bar).

[0034] In Experiment Example 12, the temperature profile for the extrusion process from Zone 1 to the die head was 185°C, 195°C, 210°C, 215°C, 220°C, 215°C, 210°C, 200°C, and 195°C. The temperature profile for the injection molding process from Zone 1 to Zone 3 was 185°C, 205°C, and 205°C. The nozzle temperature was 195°C, the holding pressure was set to 40-50-60 (bar), and the back pressure was set to 60-80 (bar).

[0035] The plastic film product in Experimental Example 8 was tested for tensile strength using the ASTM D882 standard, and the products in Experimental Examples 9-12 were tested for tensile strength using the ASTM D638 standard. The results are shown in Table 3.

[0036] As can be seen from the results of the mechanical property measurements, the raw material compositions disclosed in this invention can be used to produce materials with different mechanical properties by appropriately adjusting the ratios, and can be used according to different needs. For example, the film product of Experimental Example 8 has excellent ductility and a certain strength, and the plastic product of Experimental Example 12 has good mechanical strength. JPEG2026512921000002.jpg132170JPEG2026512921000003.jpg220170JPEG2026512921 000004.jpg218170JPEG2026512921000005.jpg136170JPEG2026512921000006.jpg52170 [Explanation of Symbols]

[0037] S1, S2, S3, S4 Step

Claims

1. Polyvinyl alcohol and Microalgae having a weight percentage of 10% to 30% based on the weight of the aforementioned polyvinyl alcohol, A compatibilizer having a weight percentage of 2% to 5% based on the weight of the aforementioned polyvinyl alcohol, A plasticizer having a weight percentage of 20% to 30% based on the weight of the aforementioned polyvinyl alcohol, A crosslinking agent having a weight percentage of 0% to 1.5% based on the weight of the aforementioned polyvinyl alcohol, A reaction aid having a weight percentage between 1% and 5% based on the weight of the aforementioned polyvinyl alcohol, A raw material composition for a thermoplastic product mixed with microalgae, comprising a lubricant having a weight percentage of 0.1% to 0.5% based on the weight of the polyvinyl alcohol.

2. The raw material composition according to claim 1, further comprising a reinforcing agent having a weight percentage of 0.2% to 0.5% based on the weight of the polyvinyl alcohol.

3. The raw material composition according to claim 1, wherein the degree of polymerization of the polyvinyl alcohol is between 300 and 2400.

4. The raw material composition according to claim 1, wherein the hydrolysis rate of the polyvinyl alcohol is between 88% and 99%.

5. The raw material composition according to claim 1, wherein the protein content of the microalgae is 30% or more.

6. The raw material composition according to claim 1, wherein the microalgae are of the genera Spirulina sp., Chlorella sp., Nannochloropsis sp., Dunaliella sp., Tetraselmis sp., or a combination thereof.

7. The raw material composition according to claim 1, wherein the plasticizer is a polyol.

8. The raw material composition according to claim 7, wherein the polyol is glycerol, polyethylene glycol, sorbitol, xylitol, mannitol, or a combination thereof.

9. The raw material composition according to claim 1, wherein the compatibilizer is gum rosin.

10. The raw material composition according to claim 1, wherein the crosslinking agent is boric acid, citric acid, adipic acid, succinic acid, or suberic acid.

11. The raw material composition according to claim 1, wherein the reaction aid is a lubricant.

12. The raw material composition according to claim 1, wherein the lubricant comprises an alkali metal salt of stearic acid.

13. A thermoplastic product containing microalgae, manufactured from the raw material composition according to any one of claims 1 to 12.

14. The step of obtaining a mixture by mixing polyvinyl alcohol, microalgae, a compatibilizer, a plasticizer, a crosslinking agent, a reaction aid, and a lubricant, wherein the weight percentage of the microalgae relative to the weight of the polyvinyl alcohol is between 10% and 30%, the weight percentage of the compatibilizer relative to the weight of the polyvinyl alcohol is between 2% and 5%, the weight percentage of the plasticizer relative to the weight of the polyvinyl alcohol is between 20% and 30%, the weight percentage of the crosslinking agent relative to the weight of the polyvinyl alcohol is between 0% and 1.5%, the weight percentage of the reaction aid relative to the weight of the polyvinyl alcohol is between 1% and 5%, and the weight percentage of the lubricant relative to the weight of the polyvinyl alcohol is between 0.1% and 0.5%. The steps include drying the mixture, The steps include: preparing pellets from the aforementioned mixture; The steps include: forming the pellets into a product, A method for producing thermoplastic products mixed with microalgae.

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