阅读说明：本技术 一种薄膜用聚乳酸组合物及其制备方法 (Polylactic acid composition for film and preparation method thereof ) 是由 涂志刚 熊立贵 张尚先 何镜奎 陈利伟 张云云 张凌涛 于 2020-01-09 设计创作，主要内容包括：本发明涉及薄膜材料制备技术领域,具体公开了一种薄膜用聚乳酸组合物及其制备方法。所述的薄膜用聚乳酸组合物,其包含如下重量份的原料组分：聚乳酸80～100份；改性环糊精10～20份；填料1～10份；润滑剂1～2份；扩链剂1～3份；抗氧剂0.1～1份。所述的薄膜用聚乳酸组合物具有较高的玻璃化转变温度以及很好的拉伸强度。(The invention relates to the technical field of film material preparation, and particularly discloses a polylactic acid composition for a film and a preparation method thereof. The polylactic acid composition for the film comprises the following raw material components in parts by weight: 80-100 parts of polylactic acid; 10-20 parts of modified cyclodextrin; 1-10 parts of a filler; 1-2 parts of a lubricant; 1-3 parts of a chain extender; 0.1-1 part of antioxidant. The polylactic acid composition for the film has higher glass transition temperature and good tensile strength.)

1. The polylactic acid composition for the film is characterized by comprising the following raw material components in parts by weight:

80-100 parts of polylactic acid; 10-20 parts of modified cyclodextrin; 1-10 parts of a filler; 1-2 parts of a lubricant; 1-3 parts of a chain extender; 0.1-1 part of antioxidant.

2. The polylactic acid composition for films according to claim 1, which comprises the following raw material components in parts by weight:

80-90 parts of polylactic acid; 10-15 parts of modified cyclodextrin; 3-6 parts of a filler; 1-2 parts of a lubricant; 1-2 parts of a chain extender; 0.5-1 part of antioxidant.

3. The polylactic acid composition for films according to claim 1, which comprises the following raw material components in parts by weight:

85 parts of polylactic acid; 12 parts of modified cyclodextrin; 3 parts of a filler; 2 parts of a lubricant; 1 part of a chain extender; 0.5 part of antioxidant.

4. The polylactic acid composition for films according to claim 1, wherein the filler is selected from the group consisting of calcium carbonate; the lubricant is selected from zinc stearate.

5. The polylactic acid composition for films according to claim 1, wherein the chain extender is selected from benzoyl peroxide.

6. The polylactic acid composition for films according to claim 1, wherein the antioxidant is selected from the group consisting of antioxidants 1076.

7. The polylactic acid composition for films according to claim 1, wherein the modified cyclodextrin is prepared by the following method: dissolving gamma-cyclodextrin in water, adding acrylic acid and polyethylene glycol (8000-10000 polyethylene glycol), adding an initiator, reacting for 4-6 h at the temperature of 60-80 ℃, cooling to room temperature, filtering, washing and drying precipitates to obtain modified cyclodextrin;

the dosage ratio of the gamma-cyclodextrin to the water is 1 g: 20-40 m L;

the weight ratio of the gamma-cyclodextrin to the acrylic acid polyethylene glycol is 1: 0.1-0.3: 5 to 10.

8. The polylactic acid composition for films according to claim 7, wherein the amount ratio of the gamma-cyclodextrin to water is 1g to 30m L;

the weight ratio of the gamma-cyclodextrin to the acrylic acid to the polyethylene glycol is 1: 0.2: 6.

9. the polylactic acid composition for films according to claim 7, wherein the initiator is ammonium persulfate; the adding amount of the ammonium persulfate is 0.5-1% of the weight of the water.

10. The method for preparing a polylactic acid composition for films according to any one of claims 1 to 9, comprising the steps of: uniformly mixing polylactic acid, modified cyclodextrin, filler, lubricant, chain extender and antioxidant, and then carrying out melt extrusion granulation by a double-screw extruder to obtain the polylactic acid composition for the film.

Technical Field

The invention relates to the technical field of film material preparation, in particular to a polylactic acid composition for a film and a preparation method thereof.

Background

Polylactic acid is a polymer obtained by polymerizing lactic acid serving as a main raw material, and a product prepared from the polylactic acid can be biodegraded, so that the polylactic acid is an ideal environment-friendly high polymer material; it is biodegradable and has excellent biocompatibility, glossiness and transparency. Therefore, polylactic acid is also a common raw material for preparing environment-friendly film materials.

However, the polylactic acid has low glass transition temperature, generally 60-65 ℃, large deformation in the heat treatment process and poor heat resistance; therefore, a polylactic acid material with a higher glass transition temperature is urgently needed.

Disclosure of Invention

The invention aims to solve the technical problem of providing a polylactic acid composition for a film, wherein the polylactic acid composition for the film has a higher glass transition temperature.

The technical problem to be solved by the invention is realized by the following technical scheme:

a polylactic acid composition for a film comprises the following raw material components in parts by weight:

80-100 parts of polylactic acid; 10-20 parts of modified cyclodextrin; 1-10 parts of a filler; 1-3 parts of a lubricant; 1-3 parts of a chain extender; 0.1-1 part of antioxidant.

Preferably, the polylactic acid composition for films comprises the following raw material components in parts by weight:

80-90 parts of polylactic acid; 10-15 parts of modified cyclodextrin; 3-6 parts of a filler; 1-2 parts of a lubricant; 1-3 parts of a chain extender; 0.5-1 part of antioxidant.

Most preferably, the polylactic acid composition for films comprises the following raw material components in parts by weight:

85 parts of polylactic acid; 12 parts of modified cyclodextrin; 3 parts of a filler; 2 parts of a lubricant; 1 part of a chain extender; 0.5 part of antioxidant.

Preferably, the filler is selected from calcium carbonate.

Preferably, the lubricant is selected from zinc stearate.

Preferably, the chain extender is selected from benzoyl peroxide.

Preferably, the antioxidant is selected from antioxidants 1076.

Preferably, the modified cyclodextrin is prepared by the following method: dissolving gamma-cyclodextrin in water, adding acrylic acid and polyethylene glycol (8000-10000 polyethylene glycol), adding an initiator, reacting for 4-6 h at the temperature of 60-80 ℃, cooling to room temperature, filtering, washing and drying precipitates to obtain modified cyclodextrin;

the dosage ratio of the gamma-cyclodextrin to the water is 1 g: 20-40 m L;

the weight ratio of the gamma-cyclodextrin to the acrylic acid polyethylene glycol is 1: 0.1-0.3: 5 to 10.

Further preferably, the dosage ratio of the gamma-cyclodextrin to the water is 1g to 30m L;

the weight ratio of the gamma-cyclodextrin to the acrylic acid to the polyethylene glycol is 1: 0.2: 6.

preferably, the initiator is ammonium persulfate; the adding amount of the ammonium persulfate is 0.5-1% of the weight of the water.

The preparation method of the polylactic acid composition for the film comprises the following steps: uniformly mixing polylactic acid, modified cyclodextrin, filler, lubricant, chain extender and antioxidant, and then carrying out melt extrusion granulation by a double-screw extruder to obtain the polylactic acid composition for the film.

Has the advantages that: the invention provides a polylactic acid composition for a film with a brand new composition, and the polylactic acid composition for the film is added with modified cyclodextrin prepared by a brand new method, so that the glass transition temperature of the polylactic acid composition is greatly improved, and the polylactic acid composition has better heat resistance; in addition, the addition of the modified cyclodextrin is also beneficial to improving the tensile strength of the polylactic acid composition for the film.

Detailed Description

The invention is further explained below with reference to specific examples, but the scope of protection described herein is not limited to the examples.