阅读说明：本技术 一种淀粉基可生物降解塑料及其制备方法及应用 (Starch-based biodegradable plastic and preparation method and application thereof ) 是由 张兆平 张乃庆 张苗苗 于 2019-11-05 设计创作，主要内容包括：本发明提供了本发明提供的一种淀粉基可生物降解塑料组合物,其特征在于,由包括酰基肌氨酸盐、磷酸、蒙脱土制备而成,其有效成分重量份数比为：酰基肌氨酸盐100、磷酸50-100、蒙脱土300-500。采用本发明制备的淀粉基可生物降解塑料组合物,可促进塑料制品的生物分解性能,增强淀粉基的物理强度和拉伸性能。本发明还提供了一种含上述淀粉基可生物降解塑料组合物的淀粉基可生物降解塑料,包括淀粉；聚丁二酸丁二醇酯(PBS)；淀粉基可生物降解塑料组合物；多元醇；海藻酸钠制备面成。(The invention provides a starch-based biodegradable plastic composition, which is characterized by being prepared from acyl sarcosinate, phosphoric acid and montmorillonite, wherein the weight parts of the effective components are as follows: 100 parts of acyl sarcosinate, 50-100 parts of phosphoric acid and 300-500 parts of montmorillonite. The starch-based biodegradable plastic composition prepared by the invention can promote the biological decomposition performance of plastic products and enhance the physical strength and tensile property of starch base. The invention also provides a starch-based biodegradable plastic containing the starch-based biodegradable plastic composition, which comprises starch; polybutylene succinate (PBS); starch-based biodegradable plastic compositions; a polyol; the sodium alginate is used for preparing the flour.)

1. A starch-based biodegradable plastic composition is characterized by being prepared from acyl sarcosinate and phosphoric acid.

2. A starch-based biodegradable plastic composition according to claim 1, characterized in that: the acyl sarcosinate is selected from one or a mixture of more of cocoyl sarcosinate sodium and lauroyl sarcosinate sodium.

3. A starch-based biodegradable plastic composition according to claim 1, characterized in that: also included are montmorillonites.

4. A starch-based biodegradable plastic composition according to claim 3, characterized in that: the acyl sarcosinate, the phosphoric acid and the montmorillonite comprise the following effective components in parts by weight: 100 parts of acyl sarcosinate, 50-100 parts of phosphoric acid and 300-500 parts of montmorillonite.

5. A starch-based biodegradable plastic composition according to claim 4, characterized in that:

the phosphoric acid is industrial phosphoric acid with the effective component not less than 50%;

the montmorillonite is preferably nano-montmorillonite with particle size not greater than 100 nm.

6. A starch-based biodegradable plastic composition according to claim 4, characterized in that: the preparation method of the starch-based biodegradable plastic composition comprises the following steps:

weighing acyl sarcosinate, phosphoric acid and montmorillonite, adding into a grinder or a homogenizer, grinding or homogenizing and stirring for 30-60 minutes to form a sticky substance, namely the starch-based biodegradable plastic composition. Or adding acyl sarcosinate, phosphoric acid, montmorillonite and water into a grinder or a homogenizer, grinding or homogenizing and stirring for 30-60 minutes to form relatively stable suspension of the composition, namely the starch-based biodegradable plastic composition.

7. The starch-based biodegradable plastic composition according to claim 6, wherein: adding nonionic surfactant 1-2% of total weight of acyl sarcosinate, phosphoric acid and montmorillonite during stirring; the nonionic surfactant is preferably fatty alcohol-polyoxyethylene ether, and more preferably one or more of commercial products AEO-9, AEO-10, AEO-12 and AEO-15.

8. The starch-based biodegradable plastic is characterized by being prepared from the following components in parts by weight:

9. the starch-based biodegradable plastic according to claim 8, wherein:

the starch is selected from one or more of corn starch, sweet potato starch and potato starch, and preferably corn starch;

the polyalcohol is preferably one or more of glycerol, trimethylolpropane, mannitol, glucose and sorbitol.

10. The method for preparing a starch-based biodegradable plastic according to claim 8 or 9, wherein:

heating starch, a starch-based biodegradable plastic composition and deionized water to 85-95 ℃, stirring and gelatinizing for about 60 minutes, adding polybutylene succinate, polyol and sodium alginate, stirring, extruding by using a screw extruder, controlling the temperature of an extrusion end at 165-175 ℃, cooling, crushing and granulating to obtain the starch-based biodegradable plastic;

the dosage of the ionic water is 2-3 times of the weight of the starch.

Technical Field

The invention belongs to the technical field of plastics, and particularly relates to a starch-based degradable plastic and a preparation method and application thereof.

Background

Since the last 90 s, the use of plastic products in the packaging field has rapidly increased for reasons of convenience, low cost, etc. The raw materials of plastic products such as PP, PE, PVC and PS wait for almost all petroleum products, are discarded in the environment after consumption and cannot be naturally degraded, and how to treat the plastic wastes becomes a global problem. The disposal of plastic waste by landfill obviously imposes a great burden on the environment, and the disposal by recycling and incineration also imposes certain influence on the environment.

For the reasons, the development of green and environment-friendly degradable plastic materials has great practical significance, and the research and application of the degradable plastics should draw attention and support of research and development institutions, enterprises and government related functional departments.

Biodegradable plastic refers to plastic that is acted upon by microorganisms existing in nature under natural environment or specific conditions and is finally completely degraded into carbon dioxide, methane, water and inorganic minerals as well as new biomass.

Disclosure of Invention

In view of the above, the present invention aims to overcome the disadvantages of the prior art and to provide a starch-based biodegradable plastic composition.

In order to achieve the above object, the present invention provides a starch-based biodegradable plastic composition, which is characterized by comprising acyl sarcosinate and phosphoric acid,

the acyl sarcosinate is one or more of coconut oil acyl sarcosinate sodium and lauroyl sarcosinate sodium. Acyl sarcosinate is a good anionic surfactant, is beneficial to forming activity on the surface of a filler and is uniformly distributed in starch-based plastics, and can promote biological decomposition of organic matters due to the existence of-NH-group necessary for microbial organisms in a molecular structure.

The phosphoric acid can be industrial phosphoric acid with the effective component not less than 50%. Phosphoric acid can react with-OH of starch to form phosphate ester when the starch-based material is processed, the ductility and tensile strength of the starch-based plastic are improved, and the existence of the element P is also beneficial to the degradation of microorganisms.

The invention provides a starch-based biodegradable plastic composition, which is characterized by further comprising montmorillonite.

The montmorillonite is preferably nano-montmorillonite with particle size not greater than 100 nm. The montmorillonite can improve the crystallinity and physical properties of the starch-based plastic and enhance the tensile strength of the starch plastic.

The invention provides a starch-based biodegradable plastic composition, which comprises the following effective components in parts by weight: 100 parts of acyl sarcosinate, 50-100 parts of phosphoric acid and 300-500 parts of montmorillonite.

When preparing the starch-based biodegradable plastic composition, it is preferable to add water in an amount of 2 to 3 times the total weight of the composition.

The invention also provides a preparation method of the starch-based biodegradable plastic composition, which comprises the following steps: weighing acyl sarcosinate, phosphoric acid and montmorillonite, adding into a grinder or a homogenizer, grinding or homogenizing and stirring for 30-60 minutes to form a sticky substance, namely the starch-based biodegradable plastic composition. Or adding acyl sarcosinate, phosphoric acid, montmorillonite and water into a grinder or a homogenizer, grinding or homogenizing and stirring for 30-60 minutes to form relatively stable suspension of the composition, namely the starch-based biodegradable plastic composition.

In order to stabilize the suspension, a nonionic surfactant which is 1-2% of the total weight of acyl sarcosinate, phosphoric acid and montmorillonite can be added in the stirring process.

The nonionic surfactant is preferably fatty alcohol-polyoxyethylene ether, and more preferably one or more of commercial products AEO-9, AEO-10, AEO-12 and AEO-15.

In addition, the invention also provides a starch-based biodegradable plastic containing the starch-based biodegradable plastic composition, which is characterized by being prepared from the following components in parts by weight:

the starch can be one or more selected from corn starch, sweet potato starch and potato starch, and preferably corn starch.

The polyalcohol is one or more selected from glycerol, trimethylolpropane, mannitol, glucose and sorbitol. Providing a plasticizing function.

The poly (butylene succinate) can be prepared by directly carrying out esterification reaction on 1, 4-butanediol and 1, 4-succinic acid. The preparation method comprises the following steps:

weighing succinic acid and 1, 4-butanediol with equal molar ratio, adding the succinic acid and the 1, 4-butanediol into a reaction kettle, stirring and heating to 230 ℃, fully reacting for 8-10 hours, and reducing pressure to discharge water for 2-3 times during and after the reaction, namely the poly (butylene succinate).

In order to accelerate the reaction process, a catalyst can be added to promote the reaction, and the catalyst can be one or a mixture of several of cation exchange resin, protonic acid and phase transfer catalyst.

The catalyst is preferably phosphoric acid with a concentration of 85%, and when phosphoric acid is selected as the catalyst, the phosphoric acid ester compound generated by the catalytic reaction does not need to be separated, so that the environmental pollution and the consumption of water, electricity, chemical reagents and the like caused by the separation of the catalyst can be reduced.

When the catalyst is phosphoric acid, the usage amount of the effective components of the phosphoric acid accounts for 0.2-0.5% of the total weight of the succinic acid and the 1, 4-butanediol.

In addition, the invention provides a preparation method of the starch-based biodegradable plastic prepared from the starch-based biodegradable plastic composition, which comprises the following steps: heating starch, a starch-based biodegradable plastic composition and deionized water (the dosage of the ionized water is generally 2-3 times of the weight of the starch, and is preferably 2-3 times of the weight of the starch, so that the ionized water can be soaked in the starch) to 85-95 ℃, stirring and pasting for about 60 minutes, adding polybutylene succinate, polyhydric alcohol and sodium alginate, stirring, extruding by using a screw extruder (the temperature of an extrusion end is generally controlled to 165-175 ℃), and cooling, crushing and granulating to obtain the starch-based biodegradable plastic.

In addition, the invention provides a using method of the starch-based biodegradable plastic prepared from the starch-based biodegradable plastic composition, which comprises the following steps: the starch-based biodegradable plastic can be directly injected into a mold or added into other plastic (such as PP or PE) to prepare snack boxes, disposable water cups, convenience food packaging boxes and the like.

Action and Effect of the invention

The starch-based biodegradable plastic composition prepared by the invention can promote the biological decomposition performance of plastic products and enhance the physical strength and tensile property of starch base.

The starch has wide sources and good degradability, has the defects of poor tensile strength, poor physical elasticity and poor acid and alkali resistance, and needs to be added with other components to enhance the physical and chemical properties.

In the invention, the poly (butylene succinate) is a good biodegradable plastic raw material, and the tensile resistance, the melting heating property, the heat resistance and the corrosion resistance can be enhanced by adding the poly (butylene succinate) into starch-based biodegradable plastic.

The polyalcohol in the invention is a good plasticizing modification auxiliary agent and can improve the performance of starch-based biodegradable plastics.

The sodium alginate in the invention is biodegradable, is a good dispersant and stabilizer, can improve the elastic gelatinization and film forming property of starch and PBS, and can improve the processing ductility of plastics.

In the formula of the invention, after the components are mixed, weak bond acting force among molecules can occur based on respective structural characteristics, and after the components are dissolved and accelerated mutually, the performances of tensile resistance, physical strength, corrosion resistance, biodegradability and the like of the components are improved and excited.

Detailed Description