阅读说明：本技术 一种新型高淀粉填充pbat及其制备方法 (Novel high-starch-filled PBAT and preparation method thereof ) 是由 涂丹 陈敏 王加浙 陈思松 陈思汕 蔡盛赢 陈盛介 于 2020-12-16 设计创作，主要内容包括：本发明公开了一种新型高淀粉填充PBAT及其制备方法,所述的新型高淀粉填充PBAT,包括以下原料：PBAT、淀粉凝胶、硅烷偶联剂KH550、交联剂、相容剂、淀粉改性剂、抗氧剂、芥酸酰胺、PE蜡、聚四氟乙烯微粉、成核剂、纳米硫酸钡,所述的新型高淀粉填充PBAT是经过制备主料、制备改性料,然后将主料、改性料、相容剂和纳米硫酸钡混合后加热,塑化,挤出,延压等步骤制成的。本发明制得的新型高淀粉填充PBAT的拉伸强度、维卡软化温度均显著高于现有技术制得的PBAT的拉伸强度、维卡软化温度,且能单独吹膜,此外降解速度快,成本远低,具有良好经济效益。(The invention discloses a novel high-starch filled PBAT and a preparation method thereof, wherein the novel high-starch filled PBAT comprises the following raw materials: PBAT, starch gel, a silane coupling agent KH550, a cross-linking agent, a compatilizer, a starch modifier, an antioxidant, erucamide, PE wax, polytetrafluoroethylene micro powder, a nucleating agent and nano barium sulfate, wherein the novel high-starch filled PBAT is prepared by preparing a main material and a modified material, mixing the main material, the modified material, the compatilizer and the nano barium sulfate, heating, plasticizing, extruding, calendering and the like. The tensile strength and the Vicat softening temperature of the novel high-starch-filled PBAT prepared by the method are obviously higher than those of the PBAT prepared by the prior art, and the PBAT can be independently blown into a film, and has the advantages of high degradation speed, low cost and good economic benefit.)

1. A novel high starch filled PBAT, characterized in that it comprises the following raw materials: PBAT, starch gel, a silane coupling agent KH550, a cross-linking agent, a compatilizer, a starch modifier, an antioxidant, erucamide, PE wax, polytetrafluoroethylene micro powder, a nucleating agent and nano barium sulfate;

the weight ratio of the PBAT to the starch gel to the silane coupling agent KH550 to the crosslinking agent to the compatilizer is (30-45): (50-60): (1-3): (2-4): (4-10).

2. The high starch gel PBAT of claim 1, characterized in that the weight ratio of PBAT, starch gel, silane coupling agent KH550, cross-linking agent, compatibilizing agent is 40: 55: 2: 3: 8.

3. the new high starch filled PBAT according to claim 1, characterized in that it comprises the following raw materials in parts by weight: PBAT30-45 parts, starch gel 50-60 parts, silane coupling agent KH 5501-3 parts, cross-linking agent 2-4 parts, compatilizer 4-10 parts, starch modifier 5-10 parts, antioxidant 1-2 parts, erucamide 2-5 parts, PE wax 2-5 parts, polytetrafluoroethylene micropowder 5-10 parts, nucleating agent 2-5 parts, and nano barium sulfate 5-10 parts.

4. A novel high starch filled PBAT according to claim 3, characterized in that it comprises the following raw materials in parts by weight: 40 parts of PBAT, 55 parts of starch gel, 2 parts of a silane coupling agent KH 5502 parts, 3 parts of a crosslinking agent, 8 parts of a compatilizer, 8 parts of a starch modifier, 1.6 parts of an antioxidant, 4 parts of erucamide, 3 parts of PE wax, 7 parts of polytetrafluoroethylene micropowder, 3 parts of a nucleating agent and 8 parts of nano barium sulfate.

5. A novel high starch filled PBAT according to any of claims 1-4, wherein the starch gel comprises the following raw materials, in parts by weight: 70-80 parts of edible starch, 20-30 parts of edible glycerin, 10-15 parts of citric acid and 20-30 parts of sodium carbonate.

6. The new high starch filled PBAT according to claim 5, characterized in that the starch gel is prepared according to the following process: uniformly mixing 20-30 parts by weight of edible glycerol and 10-15 parts by weight of citric acid at the temperature of 50-60 ℃, adding 70-80 parts by weight of edible starch, stirring for 1-1.5h to uniformly disperse the edible glycerol, stirring for 10-30min at the rotating speed of 850r/min of 650 plus materials, adding 20-30 parts by weight of sodium carbonate to adjust the pH value to 6.0-7.0, heating to 80-100 ℃, keeping the temperature for 0.5-1.0h, taking out the mixture, and cooling to room temperature to obtain the starch gel.

7. A novel high starch filled PBAT according to claim 6, wherein the edible starch comprises one or more of edible corn starch, sweet potato flour, mung bean flour.

8. The novel high starch filled PBAT of claim 1, 3 or 4, characterized in that the antioxidant comprises one or both of antioxidant 1010, antioxidant 168.

9. A method for the preparation of a novel high starch filled PBAT according to any of claims 1-8, characterized in that it comprises the following steps:

pretreating starch gel, a starch modifier and a coupling agent KH550 in a high-speed mixer, then adding PBAT, a compatilizer and nano barium sulfate, uniformly mixing, then adding a cross-linking agent, a nucleating agent, an antioxidant, erucamide, PE wax and polytetrafluoroethylene micropowder, and finally carrying out melt extrusion, bracing, air cooling and granulation by using a double-screw extruder to obtain the novel high-starch filled PBAT.

10. The method of preparing a novel high starch filled PBAT according to claim 9, characterized in that the screw length to diameter ratio of the twin screw extruder is 35-48: 1, the temperature of melt blending is 160-180 ℃.

Technical Field

The invention belongs to the technical field of PBAT material preparation, and particularly relates to a novel high-starch filled PBAT and a preparation method thereof.

Background

PBAT belongs to thermoplastic biodegradable plastic, is a copolymer of butanediol adipate and butanediol terephthalate, has the characteristics of PBA and PBT, and has better ductility and elongation at break as well as better heat resistance and impact property; in addition, the biodegradable plastic has excellent biodegradability, and is one of the best degradable materials which are very active in the research of the current biodegradable plastics and are applied to the market. However, the existing PBAT material has the problems of lower tensile strength, lower Vicat softening temperature, higher preparation cost and incapability of independently blowing the film.

Starch is an important natural biodegradable material polymer, is used as a renewable natural resource, and has the advantages of low cost and wide source. However, starch has a large number of intramolecular and intermolecular invitation cards inside, has a complex structure, is mostly in a granular state, and cannot be directly processed in a thermoplastic way. Therefore, how to improve the process is needed, so that the modified starch can be thermoplastically processed, and the new research trend is formed.

Disclosure of Invention

The invention provides a novel high-starch filled PBAT and a preparation method thereof, which are used for preparing starch into gel, solving the problems of dispersion and compatibility of the starch, greatly increasing the proportion of the starch, reducing the consumption of a base material PBAT, reducing the cost of materials, accelerating biodegradation, protecting ecological environment and saving energy.

In order to solve the technical problems, the invention adopts the following technical scheme:

a novel high starch filled PBAT comprising the following raw materials: PBAT, starch gel, a silane coupling agent KH550, a cross-linking agent, a compatilizer, a starch modifier, an antioxidant, erucamide, PE wax, polytetrafluoroethylene micro powder, a nucleating agent and nano barium sulfate;

the weight ratio of the PBAT to the starch gel to the silane coupling agent KH550 to the crosslinking agent to the compatilizer is (30-45): (50-60): (1-3): (2-4): (4-10).

Further, the weight ratio of the PBAT, the starch gel, the silane coupling agent KH550, the cross-linking agent and the compatilizer is 40: 55: 2: 3: 8.

further, the novel high-starch filled PBAT comprises the following raw materials in parts by weight: PBAT30-45 parts, starch gel 50-60 parts, silane coupling agent KH 5501-3 parts, cross-linking agent 2-4 parts, compatilizer 4-10 parts, starch modifier 5-10 parts, antioxidant 1-2 parts, erucamide 2-5 parts, PE wax 2-5 parts, polytetrafluoroethylene micropowder 5-10 parts, nucleating agent 2-5 parts, and nano barium sulfate 5-10 parts.

Further, the novel high-starch filled PBAT comprises the following raw materials in parts by weight: PBAT40 parts, starch gel 55 parts, silane coupling agent KH 5502 parts, crosslinking agent 3 parts, compatilizer 8 parts, starch modifier 8 parts, antioxidant 1.6 parts, erucamide 4 parts, PE wax 3 parts, polytetrafluoroethylene micropowder 7 parts, nucleating agent 3 parts, and nano barium sulfate 8 parts.

Further, the starch gel comprises the following raw materials in parts by weight: 70-80 parts of edible starch, 20-30 parts of edible glycerin, 10-15 parts of citric acid and 20-30 parts of sodium carbonate.

Further, the starch gel is prepared by the following process: uniformly mixing 20-30 parts by weight of edible glycerol and 10-15 parts by weight of citric acid at the temperature of 50-60 ℃, adding 70-80 parts by weight of edible starch, stirring for 1-1.5h to uniformly disperse the edible glycerol, stirring for 10-30min at the rotating speed of 850r/min of 650 plus materials, adding 20-30 parts by weight of sodium carbonate to adjust the pH value to 6.0-7.0, heating to 80-100 ℃, keeping the temperature for 0.5-1.0h, taking out the mixture, and cooling to room temperature to obtain the starch gel.

Further, the edible starch comprises one or more of edible corn starch, sweet potato powder and mung bean powder.

Further, the antioxidant comprises one or two of antioxidant 1010 and antioxidant 168.

The invention also provides a preparation method of the novel high-starch filled PBAT, which comprises the following steps:

pretreating starch gel, a starch modifier and a coupling agent KH550 in a high-speed mixer, then adding PBAT, a compatilizer and nano barium sulfate, uniformly mixing, then adding a cross-linking agent, a nucleating agent, an antioxidant, erucamide, PE wax and polytetrafluoroethylene micropowder, and finally carrying out melt extrusion, bracing, air cooling and granulation by using a double-screw extruder to obtain the novel high-starch filled PBAT.

Further, the length-diameter ratio of the screw of the double-screw extruder is 35-48: 1, the temperature of melt blending is 160-180 ℃.

The invention has the following beneficial effects:

(1) the glycerol and the sodium carbonate play a synergistic role in preparing the novel high-starch-filled PBAT, and the tensile strength and the Vicat softening temperature of the novel high-starch-filled PBAT are synergistically improved, because: in the preparation of the starch gel, citric acid is tricarboxylic acid, can form anhydride under the heating condition and then has esterification reaction with hydroxyl on starch molecules to generate citric acid starch ester which is in a cross-linked state, so that the water resistance of the starch is improved; and a certain amount of glycerin can increase the activity of starch molecular chains and promote esterification reaction, and sodium carbonate is added to obtain starch gel with good gel property, so that the tensile strength and the Vicat softening temperature of the novel high-starch filled PBAT are improved by cooperating with the glycerin.

(2) The lack of starch gel in the raw materials for preparing the novel high-starch filled PBAT of the invention has great influence on the performance of the novel high-starch filled PBAT, because: the gelatinized starch can form a semitransparent gel with certain elasticity and strength, and the starch gel is a multidimensional net structure formed by mutually connecting starch molecules and can be better added and dispersed in a base material of the material, so that the tensile strength and the Vicat softening temperature of the PBAT are improved; in addition, the starch gel prepared by the invention has good compatibility with PBAT, no starch powder layer, extremely high filling proportion and no bridging phenomenon, and can greatly reduce the cost of materials, accelerate biodegradation, protect ecological environment and save energy.

(3) The tensile strength and the Vicat softening temperature of the novel high-starch-filled PBAT prepared by the invention are both obviously higher than those of the PBAT prepared by the prior art, the novel high-starch-filled PBAT prepared by the invention can be independently blown into a film, but the PBAT prepared by the prior art can not be independently blown into the film, in addition, the number of days for completely degrading the novel high-starch-filled PBAT prepared by the invention is not more than 90 days, and is far less than the number of days (180 days) for completely degrading the PBAT prepared by the prior art, and in addition, the cost of the novel high-starch-filled PBAT prepared by the invention is far lower than that of the PBAT prepared by the prior art, and the economic benefit is good.

Detailed Description

In order to facilitate a better understanding of the invention, the following examples are given to illustrate, but not to limit the scope of the invention.

In an embodiment, the novel high starch filled PBAT comprises the following raw materials in parts by weight: 30-45 parts of PBAT, 50-60 parts of starch gel, 1-3 parts of a silane coupling agent KH550, 2-4 parts of a cross-linking agent, 4-10 parts of a compatilizer, 5-10 parts of a starch modifier, 1-2 parts of an antioxidant, 2-5 parts of erucamide, 2-5 parts of PE wax, 5-10 parts of polytetrafluoroethylene micro powder, 2-5 parts of a nucleating agent and 5-10 parts of nano barium sulfate, wherein the antioxidant comprises one or two of an antioxidant 1010 and an antioxidant 168;

the starch gel is prepared by the following process: uniformly mixing 20-30 parts by weight of edible glycerol and 10-15 parts by weight of citric acid at the temperature of 50-60 ℃, adding 70-80 parts by weight of edible starch, wherein the edible starch comprises one or more of edible corn starch, sweet potato powder and mung bean powder, stirring for 1-1.5 hours to uniformly disperse the edible starch, stirring at the rotation speed of 650 plus 850r/min for 10-30 minutes, adding 20-30 parts by weight of sodium carbonate to adjust the pH value to 6.0-7.0, heating to 80-100 ℃, keeping the temperature for 0.5-1.0 hour, taking out, and cooling to room temperature to obtain starch gel;

the preparation method of the novel high-starch filled PBAT comprises the following steps:

pretreating starch gel, a starch modifier and a coupling agent KH550 in a high-speed mixer at the temperature of 80 ℃, then adding PBAT, a compatilizer and nano barium sulfate, uniformly mixing, then adding a cross-linking agent, a nucleating agent, an antioxidant, erucamide, PE wax and polytetrafluoroethylene micro powder, finally performing melt extrusion, bracing, air cooling and granulation by using a double-screw extruder to obtain novel high-starch filled PBAT, wherein the length-diameter ratio of screws of the double-screw extruder is 35-48: 1, the temperature of melt blending is 160-180 ℃.

The following is a more specific example.

Example 1

A novel high starch filled PBAT comprises the following raw materials in parts by weight: PBAT32 parts, starch gel 50 parts, silane coupling agent KH 5501 parts, cross-linking agent 2 parts, compatilizer 5 parts, starch modifier 6 parts, antioxidant 10101 parts, erucamide 2 parts, PE wax 2 parts, polytetrafluoroethylene micropowder 5 parts, nucleating agent 2 parts, and nano barium sulfate 6 parts;

the starch gel is prepared by the following process: uniformly mixing 22 parts by weight of edible glycerol and 11 parts by weight of citric acid at the temperature of 50 ℃, adding 70 parts by weight of corn starch, stirring for 1.5 hours to uniformly disperse the corn starch, stirring for 30 minutes at the rotating speed of 650r/min, adding 20 parts by weight of sodium carbonate to adjust the pH value to 6.9, heating to 83 ℃, keeping the temperature for 0.9 hour, taking out, and cooling to room temperature to obtain starch gel;

the preparation method of the novel high-starch filled PBAT comprises the following steps:

pretreating starch gel, a starch modifier and a coupling agent KH550 in a high-speed mixer at the temperature of 80 ℃, then adding PBAT, a compatilizer and nano barium sulfate, uniformly mixing, then adding a cross-linking agent, a nucleating agent, an antioxidant, erucamide, PE wax and polytetrafluoroethylene micro powder, finally performing melt extrusion, bracing, air cooling and granulation by using a double-screw extruder to obtain novel high-starch filled PBAT, wherein the length-diameter ratio of screws of the double-screw extruder is 37: 1, the temperature of melt blending was 164 ℃.

Example 2

A novel high starch filled PBAT comprises the following raw materials in parts by weight: PBAT40 parts, starch gel 55 parts, silane coupling agent KH 5502 parts, crosslinking agent 3 parts, compatilizer 8 parts, starch modifier 8 parts, antioxidant 1681.6 parts, erucamide 4 parts, PE wax 3 parts, polytetrafluoroethylene micropowder 7 parts, nucleating agent 3 parts and nano barium sulfate 8 parts;

the starch gel is prepared by the following process: uniformly mixing 26 parts by weight of edible glycerol and 13 parts by weight of citric acid at the temperature of 54 ℃, adding 75 parts by weight of sweet potato powder, stirring for 1.3 hours to uniformly disperse the sweet potato powder, stirring for 13 minutes at the rotating speed of 800r/min, adding 26 parts by weight of sodium carbonate to adjust the pH value to 6.4, heating to 92 ℃, keeping the temperature for 0.7 hour, taking out, and cooling to room temperature to obtain starch gel;

the preparation method of the novel high-starch filled PBAT comprises the following steps:

pretreating starch gel, a starch modifier and a coupling agent KH550 in a high-speed mixer at the temperature of 80 ℃, then adding PBAT, a compatilizer and nano barium sulfate, uniformly mixing, then adding a cross-linking agent, a nucleating agent, an antioxidant, erucamide, PE wax and polytetrafluoroethylene micro powder, finally performing melt extrusion, bracing, air cooling and granulation by using a double-screw extruder to obtain novel high-starch filled PBAT, wherein the length-diameter ratio of screws of the double-screw extruder is 42: 1, the temperature of melt blending was 175 ℃.

Example 3

A novel high starch filled PBAT comprises the following raw materials in parts by weight: PBAT44 parts, starch gel 58 parts, silane coupling agent KH 5503 parts, crosslinking agent 4 parts, compatilizer 9 parts, starch modifier 9 parts, antioxidant 10102 parts, erucamide 5 parts, PE wax 4 parts, polytetrafluoroethylene micropowder 10 parts, nucleating agent 5 parts and nano barium sulfate 10 parts;

the starch gel is prepared by the following process: uniformly mixing 28 parts by weight of edible glycerol and 14 parts by weight of citric acid at the temperature of 58 ℃, adding 79 parts by weight of mung bean powder, stirring for 1.1h to uniformly disperse the mung bean powder, stirring at the rotating speed of 700r/min for 18min, adding 30 parts by weight of sodium carbonate to adjust the pH value to 6.2, heating to 87 ℃, keeping the temperature for 0.8h, taking out, and cooling to room temperature to obtain starch gel;

the preparation method of the novel high-starch filled PBAT comprises the following steps:

pretreating starch gel, a starch modifier and a coupling agent KH550 in a high-speed mixer at the temperature of 80 ℃, then adding PBAT, a compatilizer and nano barium sulfate, uniformly mixing, then adding a cross-linking agent, a nucleating agent, an antioxidant, erucamide, PE wax and polytetrafluoroethylene micro powder, finally performing melt extrusion, bracing, air cooling and granulation by using a double-screw extruder to obtain novel high-starch filled PBAT, wherein the length-diameter ratio of screws of the double-screw extruder is 46: 1, the temperature of melt blending was 178 ℃.

Comparative example 1

Essentially the same procedure as in example 2 was followed, except that the starting material for the preparation of the novel high starch filled PBAT was devoid of starch gel.

Comparative example 2

Essentially the same procedure as in example 2 was followed, except that the raw starch gel from which the novel high starch filled PBAT was prepared was devoid of glycerol and sodium carbonate.

Comparative example 3

The procedure was essentially the same as for example 2, except that the raw starch gel from which the novel high starch filled PBAT was prepared was devoid of glycerol.

Comparative example 4

Essentially the same procedure as in example 2 was followed, except that sodium carbonate was absent from the raw starch gel used to prepare the novel high starch filled PBAT.

Comparative example 5

The existing PBAT: xinjiang Lanshantun river TH801T

Carrying out various index detection on the PBAT products of the embodiments 1-3 and the comparative examples 1-5, detecting whether the film can be blown alone or not, calculating the cost, and obtaining the detection results as shown in the following table, wherein the tensile strength is detected by GB/T1040.1; the Vicat softening point temperature is detected by adopting ISO 306; the degradation performance is detected by GB/T19277.1-2011.

From the above table, it can be seen that: (1) as can be seen from the data of examples 1-3 and comparative example 5, the tensile strength and vicat softening temperature of the novel high starch filled PBAT prepared in examples 1-3 are significantly higher than those of PBAT prepared in comparative example 5 (prior art), and the novel high starch filled PBAT prepared in examples 1-3 can be blown into a film alone, while the PBAT prepared in comparative example 5 (prior art) can not be blown into a film alone, and in addition, the number of days required for complete degradation of the novel high starch filled PBAT prepared in examples 1-3 is not more than 90 days, which is much less than that of PBAT prepared in comparative example 5 (prior art) (180 days required), and the cost of the novel high starch filled PBAT prepared in examples 1-3 is much lower than that of PBAT prepared in comparative example 5 (prior art); meanwhile, as can be seen from the data of examples 1 to 3, example 2 is the most preferred example.

(2) As can be seen from the data of examples 1-3 and comparative example 1, the lack of starch gel in the raw materials to make the novel high starch filled PBAT has a great impact on the performance of the novel high starch filled PBAT because: the gelatinized starch can form translucent gel with certain elasticity and strength, and the starch gel is a multidimensional net structure formed by mutually connecting starch molecules and can be better added and dispersed in a base material of the material, so that the tensile strength and the Vicat softening temperature of the PBAT are improved.

(3) As can be seen from the data of example 1 and comparative examples 2-4, glycerol and sodium carbonate play a synergistic role in the preparation of the novel high starch filled PBAT, synergistically increasing the tensile strength, vicat softening temperature, of the novel high starch filled PBAT because: in the preparation of the starch gel, citric acid is tricarboxylic acid, can form anhydride under the heating condition and then has esterification reaction with hydroxyl on starch molecules to generate citric acid starch ester which is in a cross-linked state, so that the water resistance of the starch is improved; and a certain amount of glycerin can increase the activity of starch molecular chains and promote esterification reaction, and sodium carbonate is added to obtain starch gel with good gel property, so that the tensile strength and the Vicat softening temperature of the novel high-starch filled PBAT are improved by cooperating with the glycerin.

The above description should not be taken as limiting the invention to the embodiments, but rather, as will be apparent to those skilled in the art to which the invention pertains, numerous simplifications or substitutions may be made without departing from the spirit of the invention, which shall be deemed to fall within the scope of the invention as defined by the claims appended hereto.