阅读说明：本技术 一种可生物降解改性淀粉基玩具材料及其玩具的制备方法 (Biodegradable modified starch-based toy material and preparation method of toy thereof ) 是由 彭伟 王锦红 林勇 龙轩 李海林 李有兵 李奕萍 黄濠霖 石勇 于 2021-05-18 设计创作，主要内容包括：本发明公开一种可生物降解改性淀粉基玩具材料及其玩具的制备方法,包括以下步骤：按重量份计,将5-8份氯化钆、2-4份氯化铈、6-12份氯化钇加入至50-70份水中,然后向其中加入4-8份环烷酸和2-12份异辛酸,混合搅拌均匀后,将混合液的温度升至70-85℃后,保温1-2小时,然后冷却至室温,向其中继续加入2-5份聚乙烯亚胺和2-5份聚乙醇胺,混合搅拌均匀得改性剂；将淀粉和改性剂在70～100℃下混炼,得热塑性改性淀粉；将热塑性改性淀粉、聚乳酸、抗氧剂、增塑剂和稳定剂,加入至高速混合机中混合,采用三螺杆挤出机,经挤出后冷却、烘干、切粒。本发明方法有效提高淀粉基玩具材料的加工成型性能以及耐水性能,使其制备出断裂强度优异的可生物降解淀粉基塑料玩具。(The invention discloses a biodegradable modified starch-based toy material and a preparation method of the toy, which comprises the following steps: adding 5-8 parts by weight of gadolinium chloride, 2-4 parts by weight of cerium chloride and 6-12 parts by weight of yttrium chloride into 50-70 parts by weight of water, then adding 4-8 parts by weight of naphthenic acid and 2-12 parts by weight of isooctanoic acid into the water, uniformly mixing and stirring, raising the temperature of a mixed solution to 70-85 ℃, then preserving the heat for 1-2 hours, then cooling to room temperature, continuously adding 2-5 parts by weight of polyethyleneimine and 2-5 parts by weight of polyethanolamine into the mixed solution, uniformly mixing and stirring to obtain a modifier; mixing starch and a modifier at 70-100 ℃ to obtain thermoplastic modified starch; thermoplastic modified starch, polylactic acid, an antioxidant, a plasticizer and a stabilizer are added into a high-speed mixer for mixing, and a three-screw extruder is adopted for extrusion, cooling, drying and granulating. The method effectively improves the processing and forming performance and the water resistance of the starch-based toy material, so that the biodegradable starch-based plastic toy with excellent breaking strength is prepared.)

1. A biodegradable modified starch-based toy material, characterized in that: the preparation method comprises the following steps:

(1) adding 5-8 parts by weight of gadolinium chloride, 2-4 parts by weight of cerium chloride and 6-12 parts by weight of yttrium chloride into 50-70 parts by weight of water, then adding 4-8 parts by weight of naphthenic acid and 2-12 parts by weight of isooctanoic acid into the water, uniformly mixing and stirring, raising the temperature of a mixed solution to 70-85 ℃, carrying out heat preservation treatment for 1-2 hours, then cooling to room temperature, continuously adding 2-5 parts by weight of polyethyleneimine and 2-5 parts by weight of polyethanolamine into the mixed solution, uniformly mixing and stirring to obtain a modifier;

(2) adding starch and a modifier into an internal mixer, and mixing at 70-100 ℃ to prepare thermoplastic modified starch;

(3) adding thermoplastic modified starch, polylactic acid, an antioxidant, a plasticizer and a stabilizer into a high-speed mixer, uniformly mixing, extruding by a three-screw extruder, cooling, drying and granulating to obtain the modified starch-based toy material.

2. The biodegradable modified starch-based toy material according to claim 1, characterized in that: the proportion of the starch to the modifier in the step (2) is respectively 92-95 parts and 5-8 parts by weight.

3. The biodegradable modified starch-based toy material according to claim 2, characterized in that: the proportions of the thermoplastic modified starch, the polylactic acid, the antioxidant, the plasticizer and the stabilizer in the step (3) are respectively 60-70 parts, 30-35 parts, 0.1-0.3 part, 0.5-2 parts and 0.2-0.4 part by weight.

4. A biodegradable modified starch-based toy material according to claim 3, characterized in that: the antioxidant is one or more of phosphite ester, 2, 6-di-tert-butylphenol, thiopropionate and bis-salicylidene diamine.

5. The biodegradable modified starch-based toy material according to claim 4, characterized in that: the plasticizer is one or more of dioctyl phthalate and dibutyl phthalate.

6. The biodegradable modified starch-based toy material according to claim 5, characterized in that: the stabilizer is one or more of isooctanoic acid, calcium isooctanoate and zinc isooctanoate.

7. The biodegradable modified starch-based toy material according to claim 6, characterized in that: the antioxidant is 2, 6-di-tert-butylphenol, the plasticizer is dibutyl phthalate, and the stabilizer is zinc isooctanoate.

8. The biodegradable modified starch-based toy material according to claim 1, characterized in that: the barrel temperature of the three-screw extruder is as follows: the front section is 100-120 ℃, the middle section is 130-150 ℃, and the rear section is 150-180 ℃; the rotating speed of the screw is 12-20 r/min, and the pressure is 5-10 MPa.

9. A method of making a toy using the biodegradable modified starch-based toy material according to any one of claims 1-8, characterized in that: the method comprises the following steps:

(1) injecting the modified starch-based toy material into a storage barrel of an injection molding machine, setting the heating temperature of a screw in the storage barrel to be 70-135 ℃, extruding and melting the injection molding raw material, and maintaining the injection molding raw material in a molten state; then adjusting the temperature of the fixed die and the movable die to 30-60 ℃; setting the injection pressure to be 50-120bar, the injection time to be 2-6s and the injection speed to be 500-800mm/s, and injecting after the die is closed;

(2) entering a pressure maintaining state after the injection is finished, and setting the pressure maintaining pressure to be 90-120bar and the pressure maintaining time to be 1-3 s; cooling for 4-15s after pressure maintaining; and opening the mold, and taking out the product after demolding to obtain the biodegradable plastic toy.

Technical Field

The invention relates to a starch-based toy material, in particular to a biodegradable modified starch-based toy material and a preparation method of a toy thereof.

Background

Starch-based plastics are currently the major biodegradable plastics used in a large number of various packaging plastic products. The starch-based plastic is a plastic product which is prepared by taking starch as a main raw material, modifying and plasticizing the starch and then blending the starch with other polymers. However, starch is a natural high molecular polymer, and the molecules of the starch contain a large number of hydroxyl groups (molecular structures II and III), so that the interaction force between starch macromolecules is strong, and therefore, the starch does not have thermoplasticity, is difficult to form and process, and has poor water resistance. Therefore, the compatibility of starch and base resin is poor, the processing and forming performance of the material is affected, the existing common solution is to use a small-molecular polar plasticizer for thermoplastic treatment, but the water resistance of the obtained starch-based plastic is still poor. Therefore, the toy made of the existing starch-based plastic has poor water resistance, the service life of the toy after being soaked in water is shortened rapidly, the use feeling and the experience effect are influenced, and the oxidation resistance and the corrosion resistance are obviously insufficient. In addition, the existing starch-based plastic is easy to age and difficult to recover, so that the cost is high, and the popularization is greatly limited.

Disclosure of Invention

The invention aims to provide a biodegradable modified starch-based toy material, which improves the processing and forming properties and the water resistance of the starch-based toy material.

Another object of the present invention is to provide a method for preparing a toy from a biodegradable modified starch-based toy material.

In order to realize the first invention, the following technical scheme is adopted:

a biodegradable modified starch-based toy material is prepared by the following steps:

(1) adding 5-8 parts by weight of gadolinium chloride, 2-4 parts by weight of cerium chloride and 6-12 parts by weight of yttrium chloride into 50-70 parts by weight of water, then adding 4-8 parts by weight of naphthenic acid and 2-12 parts by weight of isooctanoic acid into the water, uniformly mixing and stirring, raising the temperature of a mixed solution to 70-85 ℃, carrying out heat preservation treatment for 1-2 hours, then cooling to room temperature, continuously adding 2-5 parts by weight of polyethyleneimine and 2-5 parts by weight of polyethanolamine into the mixed solution, uniformly mixing and stirring to obtain a modifier;

(2) adding starch and a modifier into an internal mixer, and mixing at 70-100 ℃ to prepare thermoplastic modified starch;

(3) adding thermoplastic modified starch, polylactic acid, an antioxidant, a plasticizer and a stabilizer into a high-speed mixer, uniformly mixing, extruding by a three-screw extruder, cooling, drying and granulating to obtain the modified starch-based toy material.

The proportion of the starch to the modifier in the step (2) is respectively 92-95 parts and 5-8 parts by weight.

The proportions of the thermoplastic modified starch, the polylactic acid, the antioxidant, the plasticizer and the stabilizer in the step (3) are respectively 60-70 parts, 30-35 parts, 0.1-0.3 part, 0.5-2 parts and 0.2-0.4 part by weight.

The barrel temperature of the three-screw extruder is as follows: the front section is 100-120 ℃, the middle section is 130-150 ℃, and the rear section is 150-180 ℃; the rotating speed of the screw is 12-20 r/min, and the pressure is 5-10 MPa.

The antioxidant is one or more of phosphite ester, 2, 6-di-tert-butylphenol, thiopropionate and bis-salicylidene diamine.

The plasticizer is one or more of dioctyl phthalate and dibutyl phthalate.

The stabilizer is one or more of isooctanoic acid, calcium isooctanoate and zinc isooctanoate.

Further, the antioxidant is 2, 6-di-tert-butylphenol, the plasticizer is dibutyl phthalate, and the stabilizer is zinc isooctanoate.

In order to realize the second invention, the following technical scheme is adopted:

a method for preparing a toy by adopting biodegradable modified starch-based toy material comprises the following steps:

(1) injecting the modified starch-based toy material into a storage barrel of an injection molding machine, setting the heating temperature of a screw in the storage barrel to be 70-135 ℃, extruding and melting the injection molding raw material, and maintaining the injection molding raw material in a molten state; then adjusting the temperature of the fixed die and the movable die to 30-60 ℃; setting the injection pressure to be 50-120bar, the injection time to be 2-6s and the injection speed to be 500-800mm/s, and injecting after the die is closed;

(2) entering a pressure maintaining state after the injection is finished, and setting the pressure maintaining pressure to be 90-120bar and the pressure maintaining time to be 1-3 s; cooling for 4-15s after the pressure maintaining is finished; and opening the mold, and taking out the product after demolding to obtain the biodegradable plastic toy.

The invention has the following beneficial effects:

according to the invention, the starch is mixed and esterified by adopting the modifier, so that the starch has thermoplasticity, the processing and forming performance of the starch-based toy material is improved, and the toy with excellent performance can be obtained through extrusion and injection molding processes; meanwhile, the mechanical property and the water resistance of the starch-based toy material are improved, and the oxidation resistance and the corrosion resistance of the starch-based toy material are also improved.

The biodegradable starch-based plastic toy product with excellent breaking strength and high density can be obtained by adopting specific component proportion and injection molding process parameters.

The starch-based toy material and the toy prepared by the method have excellent performance, so that the cost is lower compared with the existing starch-based plastic, and the starch-based toy material and the toy are suitable for large-scale industrial production.

Detailed Description

The following examples are only for illustrating the present invention, and the scope of the present invention is not limited to only the following examples. The objectives of the present invention can be achieved by the ordinary skilled person in the art according to the disclosure of the present invention and the ranges of the parameters.

Example 1

A biodegradable modified starch-based toy material is prepared by the following steps:

(1) adding 5 parts of gadolinium chloride, 4 parts of cerium chloride and 7 parts of yttrium chloride into 70 parts of water by weight, then adding 5 parts of naphthenic acid and 3 parts of isooctanoic acid into the water, uniformly mixing and stirring, raising the temperature of a mixed solution to 70 ℃, carrying out heat preservation treatment for 1 hour, then cooling to room temperature, continuously adding 3 parts of polyethyleneimine and 3 parts of polyethanolamine into the mixed solution, and uniformly mixing and stirring to obtain a starch modifier;

(2) adding 94 parts of starch and 6 parts of modifier into an internal mixer, and mixing at 80 ℃ to prepare thermoplastic modified starch;

(3) adding 64.5 parts by weight of thermoplastic modified starch, 33 parts by weight of polylactic acid, 0.3 part by weight of antioxidant, 0.5 part by weight of plasticizer and 0.2 part by weight of stabilizer into a high-speed mixer, uniformly mixing, extruding by a three-screw extruder, cooling, drying and granulating to obtain a modified starch-based toy material; the extruder parameters were as follows: barrel temperature: the front section is 110 ℃, the middle section is 140 ℃ and the rear section is 170 ℃; the rotating speed of the screw is 18r/min, and the pressure is 8 MPa.

Wherein the antioxidant adopts 2, 6-di-tert-butylphenol; the plasticizer adopts dibutyl phthalate; the stabilizer adopts zinc isooctoate.

The toy is prepared by adopting the modified starch-based toy material:

(1) drying the dried modified plastic particles for 1h at 100 ℃, injecting the dried modified plastic particles into a storage barrel of an injection molding machine, setting the heating temperature of a screw in the storage barrel to be 105 ℃, extruding and melting the injection molding raw materials, and maintaining the injection molding raw materials in a molten state; then adjusting the temperature of the fixed die and the movable die to 40 ℃; setting the injection pressure to be 80bar, the injection time to be 5s and the injection speed to be 600mm/s, and injecting after the die is closed;

(2) after the injection is finished, the injection enters a pressure maintaining state, the pressure maintaining pressure is set to be 110bar, and the pressure maintaining time is set to be 2 s; cooling for 5s after the pressure maintaining is finished; and opening the mold, and taking out the product after demolding to obtain the biodegradable modified plastic toy.

Example 2

A biodegradable modified starch-based toy material is prepared by the following steps:

(1) adding 6 parts by weight of gadolinium chloride, 4 parts by weight of cerium chloride and 6 parts by weight of yttrium chloride into 70 parts by weight of water, then adding 5 parts by weight of naphthenic acid and 4 parts by weight of isooctanoic acid into the water, uniformly mixing and stirring, raising the temperature of a mixed solution to 70 ℃, carrying out heat preservation treatment for 1 hour, then cooling to room temperature, continuously adding 2 parts by weight of polyethyleneimine and 3 parts by weight of polyethanolamine into the mixed solution, and uniformly mixing and stirring to obtain a starch modifier;

(2) adding 93 parts of starch and 7 parts of modifier into an internal mixer, and mixing at 90 ℃ to prepare thermoplastic modified starch;

(3) adding 65 parts by weight of thermoplastic modified starch, 34.5 parts by weight of polylactic acid, 0.2 part by weight of antioxidant, 0.5 part by weight of plasticizer and 0.3 part by weight of stabilizer into a high-speed mixer, uniformly mixing, extruding by using a three-screw extruder, cooling, drying and granulating to obtain a modified starch-based toy material; the extruder parameters were as follows: barrel temperature: the front section is 115 ℃, the middle section is 145 ℃ and the rear section is 165 ℃; the rotating speed of the screw is 16r/min, and the pressure is 7 MPa.

Wherein the antioxidant adopts 2, 6-di-tert-butylphenol; the plasticizer adopts dibutyl phthalate; the stabilizer adopts zinc isooctoate.

The toy is prepared by adopting the modified starch-based toy material:

(1) drying the dried modified plastic particles for 2h at 100 ℃, injecting the dried modified plastic particles into a storage barrel of an injection molding machine, setting the heating temperature of a screw in the storage barrel to be 105 ℃, extruding and melting the injection molding raw materials, and maintaining the injection molding raw materials in a molten state; then adjusting the temperature of the fixed die and the movable die to 40 ℃; setting the injection pressure to be 80bar, the injection time to be 5s and the injection speed to be 600mm/s, and injecting after the die is closed;

(2) after the injection is finished, the injection enters a pressure maintaining state, the pressure maintaining pressure is set to be 100bar, and the pressure maintaining time is set to be 1 s; cooling for 5s after the pressure maintaining is finished; and opening the mold, and taking out the product after demolding to obtain the biodegradable modified plastic toy.

Example 3

A biodegradable modified starch-based toy material is prepared by the following steps:

(1) adding 7 parts by weight of gadolinium chloride, 3 parts by weight of cerium chloride and 8 parts by weight of yttrium chloride into 70 parts by weight of water, then adding 4 parts by weight of naphthenic acid and 2 parts by weight of isooctanoic acid into the water, uniformly mixing and stirring, raising the temperature of a mixed solution to 70 ℃, carrying out heat preservation treatment for 1 hour, then cooling to room temperature, continuously adding 2 parts by weight of polyethyleneimine and 4 parts by weight of polyethanolamine into the mixed solution, and uniformly mixing and stirring to obtain a starch modifier;

(2) adding 93 parts of starch and 7 parts of modifier into an internal mixer, and mixing at 95 ℃ to prepare thermoplastic modified starch;

(3) adding 65 parts by weight of thermoplastic modified starch, 34.5 parts by weight of polylactic acid, 0.2 part by weight of antioxidant, 0.5 part by weight of plasticizer and 0.3 part by weight of stabilizer into a high-speed mixer, uniformly mixing, extruding by using a three-screw extruder, cooling, drying and granulating to obtain the modified starch-based toy material extruder, wherein the parameters of the extruder are as follows: barrel temperature: the front section is 120 ℃, the middle section is 150 ℃, and the rear section is 180 ℃; the rotating speed of the screw is 20r/min, and the pressure is 10 MPa.

Wherein the antioxidant adopts 2, 6-di-tert-butylphenol; the plasticizer adopts dibutyl phthalate; the stabilizer adopts zinc isooctoate.

The toy is prepared by adopting the modified starch-based toy material:

(1) drying the dried modified plastic particles for 3h at 100 ℃, injecting the dried modified plastic particles into a storage barrel of an injection molding machine, setting the heating temperature of a screw in the storage barrel to be 110 ℃, extruding and melting the injection molding raw materials, and maintaining the injection molding raw materials in a molten state; then adjusting the temperature of the fixed die and the movable die to 40 ℃; setting the injection pressure to be 100bar, the injection time to be 6s and the injection speed to be 700mm/s, and injecting after the die is closed;

(2) after the injection is finished, the injection enters a pressure maintaining state, the pressure maintaining pressure is set to be 100bar, and the pressure maintaining time is set to be 1 s; cooling for 5s after the pressure maintaining is finished; and opening the mold, and taking out the product after demolding to obtain the biodegradable modified plastic toy.

Example 4

A biodegradable modified starch-based toy material is prepared by the following steps:

(1) adding 8 parts of gadolinium chloride, 2 parts of cerium chloride and 6 parts of yttrium chloride into 70 parts of water, then adding 8 parts of naphthenic acid and 2 parts of isooctanoic acid into the water, uniformly mixing and stirring, raising the temperature of a mixed solution to 85 ℃, carrying out heat preservation treatment for 1 hour, then cooling to room temperature, continuously adding 5 parts of polyethyleneimine and 2 parts of polyethanolamine into the mixed solution, and uniformly mixing and stirring to obtain a starch modifier;

(2) adding 92 parts of starch and 8 parts of modifier into an internal mixer, and mixing at 70 ℃ to prepare thermoplastic modified starch;

(3) adding 60 parts by weight of thermoplastic modified starch, 35 parts by weight of polylactic acid, 0.3 part by weight of antioxidant, 0.5 part by weight of plasticizer and 0.4 part by weight of stabilizer into a high-speed mixer, uniformly mixing, adopting a three-screw extruder, cooling, drying and granulating after extrusion to obtain the modified starch-based toy material extruder, wherein the parameters of the extruder are as follows: barrel temperature: the front section is 120 ℃, the middle section is 150 ℃, and the rear section is 180 ℃; the rotating speed of the screw is 12r/min, and the pressure is 5 MPa.

Wherein the antioxidant adopts phosphite ester and 2, 6-di-tert-butylphenol; the plasticizer adopts dibutyl phthalate; isooctanoic acid is used as a stabilizer.

The toy is prepared by adopting the modified starch-based toy material:

(1) drying the dried modified plastic particles for 3h at 100 ℃, injecting the dried modified plastic particles into a storage barrel of an injection molding machine, setting the heating temperature of a screw in the storage barrel to be 135 ℃, extruding and melting the injection molding raw materials, and maintaining the injection molding raw materials in a molten state; then adjusting the temperature of the fixed die and the movable die to 60 ℃; setting the injection pressure to be 50bar, the injection time to be 2s and the injection speed to be 500mm/s, and injecting after the die is closed;

(2) after the injection is finished, the injection enters a pressure maintaining state, the pressure maintaining pressure is set to be 90bar, and the pressure maintaining time is set to be 1 s; cooling for 15s after the pressure maintaining is finished; and opening the mold, and taking out the product after demolding to obtain the biodegradable modified plastic toy.

Example 5

A biodegradable modified starch-based toy material is prepared by the following steps:

(1) adding 5 parts by weight of gadolinium chloride, 4 parts by weight of cerium chloride and 12 parts by weight of yttrium chloride into 50 parts by weight of water, then adding 4 parts by weight of naphthenic acid and 12 parts by weight of isooctanoic acid into the water, uniformly mixing and stirring, raising the temperature of a mixed solution to 85 ℃, carrying out heat preservation treatment for 2 hours, then cooling to room temperature, continuously adding 2 parts by weight of polyethyleneimine and 5 parts by weight of polyethanolamine into the mixed solution, and uniformly mixing and stirring to obtain a modifier of starch;

(2) according to the parts by weight, 95 parts of starch and 5 parts of modifier are added into an internal mixer and mixed at 100 ℃ to prepare thermoplastic modified starch;

(3) adding 70 parts by weight of thermoplastic modified starch, 30 parts by weight of polylactic acid, 0.1 part by weight of antioxidant, 2 parts by weight of plasticizer and 0.2 part by weight of stabilizer into a high-speed mixer, uniformly mixing, adopting a three-screw extruder, and cooling, drying and granulating after extrusion to obtain the modified starch-based toy material extruder with the following parameters: barrel temperature: the front section is 100 ℃, the middle section is 130 ℃ and the rear section is 150 ℃; the rotating speed of the screw is 20r/min, and the pressure is 10 MPa.

Wherein the antioxidant adopts thiopropionate and bis-salicylidene diamine; the plasticizer is dioctyl phthalate; the stabilizer adopts calcium isooctanoate and zinc isooctanoate.

The toy is prepared by adopting the modified starch-based toy material:

(1) drying the dried modified plastic particles for 3h at 100 ℃, injecting the dried modified plastic particles into a storage barrel of an injection molding machine, setting the heating temperature of a screw in the storage barrel to be 70 ℃, and extruding and melting injection molding raw materials and maintaining the injection molding raw materials in a molten state; then adjusting the temperature of the fixed die and the movable die to 30 ℃; setting the injection pressure to be 120bar, the injection time to be 6s and the injection speed to be 800mm/s, and injecting after the die is closed;

(2) entering a pressure maintaining state after the injection is finished, and setting the pressure maintaining pressure to be 120bar and the pressure maintaining time to be 3 s; cooling for 4s after the pressure maintaining is finished; and opening the mold, and taking out the product after demolding to obtain the biodegradable modified plastic toy.

The biodegradable modified starch-based toy materials of examples 1-3 were tested for breaking strength and elongation at break according to the test methods for tensile Properties of plastics GB/T1040-92, the results of which are given in the following table.

The comparative example is a common starch-based plastic, and from the results in the table above, it can be seen that the materials of examples 1-3 both have better breaking strength and elongation at break than the comparative example; after 48 hours of immersion, the breaking strength and elongation at break of the materials of examples 1-3 were still at the same level before immersion, whereas the values of breaking strength and elongation at break of the comparative example material were reduced after immersion, in particular the breaking strength was significantly reduced. The above results demonstrate that the method of the present invention effectively improves the mechanical properties and water resistance of starch-based toy materials, and that the improvement in mechanical properties also manifests itself in improved oxidation resistance and corrosion resistance.

The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The above-described embodiments of the present invention are to be considered in all respects as illustrative and not restrictive. Therefore, any minor modifications, equivalent changes and modifications to the above embodiments according to the spirit of the present invention are within the scope of the technical solution of the present invention.