阅读说明：本技术 一种生物可降解保护膜的制备方法 (Preparation method of biodegradable protective film ) 是由 金小林 刘宏波 王述明 于 2021-06-25 设计创作，主要内容包括：本发明公开了一种生物可降解保护膜的制备方法,保护膜包括由上至下依次设置的基材层、第一改性层和第二改性层,基材层包括以下按重量份计的各组分：葡聚糖20～35份、透明质酸18～27份、硫酸软骨素15～19份、甲基聚甘油脂肪酸酯十三碳烷基酯13～16份和添加剂17～21份。本发明的制备的保护膜不仅具有很好的生物可降解性,且具有较高的拉伸强度、耐水性和柔软性。(The invention discloses a preparation method of a biodegradable protective film, wherein the protective film comprises a base material layer, a first modified layer and a second modified layer which are sequentially arranged from top to bottom, and the base material layer comprises the following components in parts by weight: 20-35 parts of glucan, 18-27 parts of hyaluronic acid, 15-19 parts of chondroitin sulfate, 13-16 parts of methyl polyglycerol fatty acid ester tridecyl ester and 17-21 parts of additive. The protective film prepared by the invention has good biodegradability, and has high tensile strength, water resistance and flexibility.)

1. The preparation method of the biodegradable protective film is characterized in that the protective film comprises a base material layer, a first modified layer and a second modified layer which are sequentially arranged from top to bottom, wherein the base material layer comprises the following components in parts by weight: 20-35 parts of glucan, 18-27 parts of hyaluronic acid, 15-19 parts of chondroitin sulfate, 13-16 parts of methyl polyglycerol fatty acid ester tridecyl ester and 17-21 parts of additive, wherein the first modification layer comprises the following components in parts by weight: 33-42 parts of polybutylene succinate, 26-31 parts of polylactic acid, 14-20 parts of polyvinyl alcohol, 10-13 parts of citric acid and 7-9 parts of a polymerization initiator, wherein the second modification layer comprises the following components in parts by weight: 23-28 parts of nano silicon dioxide, 15-21 parts of aluminum hydroxide, 11-13 parts of ethyl acetate and 4-8 parts of polyglycerol fatty acid ester.

2. The method for preparing a biodegradable protective film according to claim 1, wherein the additive comprises the following components in a mass ratio of (5-8): (3-4): (2-3) methanol, trifluoroacetic acid and sodium silicate.

3. The method for preparing a biodegradable protective film according to claim 2, wherein the preparation steps of the additive are as follows: dividing methanol into two equal parts, adding weighed trifluoroacetic acid, sodium silicate and the first part of methanol into a reaction container, and continuously stirring for 15-25 min to obtain the additive.

4. The method for preparing a biodegradable protective film according to claim 3, wherein the substrate layer is prepared by the following steps: putting required amounts of dextran, hyaluronic acid, chondroitin sulfate and methyl polyglycerol fatty acid ester tridecyl ester into a reaction container, continuously stirring and mixing for 10-15 min, slowly adding an additive, continuously stirring until the additive is added, slowly adding a second portion of methanol, and continuously stirring until the methanol is added to obtain a mixture; putting the mixture into a double-screw extruder for mixing and melting to obtain a mixed material, cooling after mixing is finished, and granulating after cooling to room temperature; and (3) drying the obtained particles in drying equipment, and then placing the particles in a film blowing machine for film blowing to obtain a substrate layer.

5. The method for preparing a biodegradable protective film according to claim 4, wherein the temperature of the reaction vessel before the raw materials are put in is 50-60 ℃, the raw materials are added and then the temperature is kept raised under continuous stirring, and the temperature raising rate is 2-3 ℃/min.

6. The method for preparing a biodegradable protective film according to claim 1, wherein the first modified layer is prepared by the following steps: placing polybutylene succinate, polylactic acid and polyvinyl alcohol into a reaction vessel, reacting at 65-70 ℃ for 20-30 min, adding citric acid and a polymerization initiator, raising the temperature to 80-95 ℃, and reacting for 30-45 min to obtain the first modified layer coating.

7. The method as claimed in claim 1, wherein the polymerization initiator is one of benzoyl peroxide, azobisisobutyronitrile and tert-butyl peroxybenzoate.

8. The method for preparing a biodegradable protective film according to claim 1, wherein the second modified layer is prepared by the following steps: and (3) placing the nano silicon dioxide, the aluminum hydroxide, the ethyl acetate and the polyglycerol fatty acid ester into a reaction vessel, placing the reaction vessel at the temperature of 75-90 ℃, and reacting for 35-50 min to obtain the second modified layer coating.

9. The method for preparing a biodegradable protective film according to any one of claims 1-8, wherein the protective film is prepared by the following steps: preheating the prepared substrate layer, coating a first modified layer coating on the lower surface of the substrate layer when the substrate layer is heated to 45-55 ℃, and reacting at 85-95 ℃ for 0.5-1.5 h to form a first modified layer; and coating a second modified layer coating on the lower surface of the first modified layer, reacting at 85-95 ℃ for 0.5-1.5 h to form a second modified layer, cooling, and cutting to obtain the protective film.

Technical Field

The invention belongs to the technical field of processing of protective films, and particularly relates to a preparation method of a biodegradable protective film.

Background

Along with the development of scientific technology, the application and production scale of protective films are continuously enlarged, the protective films are widely applied to automobile glass, door and window glass, display screens, mobile phone shells and the like, the protective films have a good use effect, but a large amount of protective film waste materials are generated at the same time, if the protective films are directly discarded in soil after being used, the pollution to the soil environment can be caused, great harm is brought to the life of people, in order to relieve the pollution of waste plastics to the environment, the protective films can be prepared by adopting biodegradable materials, certain defects exist in the existing degradable environment-friendly release films during use, the toughness is poor, the films are easy to break due to pulling during use, inconvenience is brought to the use of the degradable environment-friendly release films, and therefore, the preparation method of the traditional biodegradable protective films is necessary to be improved.

Disclosure of Invention

In order to overcome the defects in the prior art, the invention aims to improve the preparation method of the biodegradable protective film, which not only has good biodegradability, but also has higher tensile strength, water resistance and flexibility.

In order to achieve the above object, the present invention adopts the following technical solutions:

the preparation method of the biodegradable protective film comprises a base material layer, a first modified layer and a second modified layer which are sequentially arranged from top to bottom, wherein the base material layer comprises the following components in parts by weight: 20-35 parts of glucan, 18-27 parts of hyaluronic acid, 15-19 parts of chondroitin sulfate, 13-16 parts of methyl polyglycerol fatty acid ester tridecyl ester and 17-21 parts of additive, wherein the first modification layer comprises the following components in parts by weight: 33-42 parts of polybutylene succinate, 26-31 parts of polylactic acid, 14-20 parts of polyvinyl alcohol, 10-13 parts of citric acid and 7-9 parts of a polymerization initiator, wherein the second modification layer comprises the following components in parts by weight: 23-28 parts of nano silicon dioxide, 15-21 parts of aluminum hydroxide, 11-13 parts of ethyl acetate and 4-8 parts of polyglycerol fatty acid ester.

Preferably, the additive comprises the following components in a mass ratio of (5-8): (3-4): (2-3) methanol, trifluoroacetic acid and sodium silicate.

Still preferably, the preparation steps of the aforementioned additive are as follows: dividing methanol into two equal parts, adding weighed trifluoroacetic acid, sodium silicate and the first part of methanol into a reaction container, and continuously stirring for 15-25 min to obtain the additive.

More preferably, the preparation step of the substrate layer is as follows: putting required amounts of dextran, hyaluronic acid, chondroitin sulfate and methyl polyglycerol fatty acid ester tridecyl ester into a reaction container, continuously stirring and mixing for 10-15 min, slowly adding an additive, continuously stirring until the additive is added, slowly adding a second portion of methanol, and continuously stirring until the methanol is added to obtain a mixture; putting the mixture into a double-screw extruder for mixing and melting to obtain a mixed material, cooling after mixing is finished, and granulating after cooling to room temperature; and (3) drying the obtained particles in drying equipment, and then placing the particles in a film blowing machine for film blowing to obtain a substrate layer.

Further preferably, the temperature of the reaction vessel before the raw materials are put therein is 50 to 60 ℃, the temperature of the reaction vessel is kept raised under continuous stirring after the raw materials are added, and the temperature raising rate is 2 to 3 ℃/min.

Specifically, the preparation steps of the first modified layer are as follows: placing polybutylene succinate, polylactic acid and polyvinyl alcohol into a reaction vessel, reacting at 65-70 ℃ for 20-30 min, adding citric acid and a polymerization initiator, raising the temperature to 80-95 ℃, and reacting for 30-45 min to obtain the first modified layer coating.

Preferably, the polymerization initiator is one of benzoyl peroxide, azobisisobutyronitrile and tert-butyl peroxybenzoate.

Still preferably, the preparation steps of the second modified layer are as follows: and (3) placing the nano silicon dioxide, the aluminum hydroxide, the ethyl acetate and the polyglycerol fatty acid ester into a reaction vessel, placing the reaction vessel at the temperature of 75-90 ℃, and reacting for 35-50 min to obtain the second modified layer coating.

More preferably, the preparation steps of the protective film are as follows: preheating the prepared substrate layer, coating a first modified layer coating on the lower surface of the substrate layer when the substrate layer is heated to 45-55 ℃, and reacting at 85-95 ℃ for 0.5-1.5 h to form a first modified layer; and coating a second modified layer coating on the lower surface of the first modified layer, reacting at 85-95 ℃ for 0.5-1.5 h to form a second modified layer, cooling, and cutting to obtain the protective film.

The invention has the advantages that:

(1) the protective film prepared by the invention has good biodegradability, high tensile strength, water resistance and flexibility, is not easy to tear in the using process, and effectively improves the product quality;

(2) the dextran, the hyaluronic acid and the chondroitin sulfate have good degradability and biocompatibility, and degraded products are nontoxic, so that the problem of environmental pollution is effectively avoided; the added trifluoroacetic acid, sodium silicate and methanol can reduce intramolecular and intermolecular hydrogen bonds formed among glucan, hyaluronic acid and chondroitin sulfate, and the formation of the hydrogen bonds can be further limited by keeping the temperature rise in the preparation process of the base material layer so as to reduce the influence of the hydrogen bonds on the melting process, thereby effectively promoting the preparation process of the base material layer;

(3) the lower surface of the base material layer is coated with a first modified layer coating, wherein polybutylene succinate, polylactic acid and polyvinyl alcohol react under the action of citric acid and a polymerization initiator to form a polymerization modified system, the adhesion force is good, and the water resistance and flexibility of the protective film can be effectively improved after the protective film is combined with the base material layer;

(4) the nano silicon dioxide and the aluminum hydroxide added into the second modified layer have good interface binding force, and the ethyl acetate and the polyglycerol fatty acid ester can be chemically bonded, so that the use strength of the protective film is effectively improved.

Detailed Description

The present invention will be described in detail with reference to the following embodiments.

Example 1

The preparation method of the biodegradable protective film comprises a base material layer, a first modified layer and a second modified layer which are sequentially arranged from top to bottom, wherein the base material layer comprises the following components in parts by weight: 20 parts of glucan, 18 parts of hyaluronic acid, 15 parts of chondroitin sulfate, 13 parts of methyl polyglycerol fatty acid ester tridecyl ester and 17 parts of additive, wherein the first modified layer comprises the following components in parts by weight: 33 parts of polybutylene succinate, 26 parts of polylactic acid, 14 parts of polyvinyl alcohol, 10 parts of citric acid and 7 parts of polymerization initiator benzoyl peroxide, wherein the second modification layer comprises the following components in parts by weight: 23 parts of nano silicon dioxide, 15 parts of aluminum hydroxide, 11 parts of ethyl acetate and 4 parts of polyglycerol fatty acid ester.

Wherein the additive comprises the following components in percentage by mass: 3: 2, and sodium silicate, the preparation steps of the additive are as follows: dividing methanol into two equal parts, adding weighed trifluoroacetic acid, sodium silicate and the first part of methanol into a reaction vessel, and continuously stirring for 15min to obtain the additive.

The preparation steps of the substrate layer are as follows: putting required amounts of dextran, hyaluronic acid, chondroitin sulfate and methyl polyglycerol fatty acid ester tridecyl ester into a reaction container, wherein the initial temperature of the reaction container is 50-60 ℃, adding all raw materials, keeping heating while continuously stirring, keeping the heating rate at 2-3 ℃/min, continuously stirring and mixing for 10-15 min, slowly adding an additive, continuously stirring until the additive is added, slowly adding a second part of methanol, and continuously stirring until the methanol is added to obtain a mixture; putting the mixture into a double-screw extruder for mixing and melting to obtain a mixed material, cooling after mixing is finished, and granulating after cooling to room temperature; and (3) drying the obtained particles in drying equipment, and then placing the particles in a film blowing machine for film blowing to obtain a substrate layer.

The first modified layer was prepared as follows: placing polybutylene succinate, polylactic acid and polyvinyl alcohol into a reaction vessel, reacting at 65-70 ℃ for 20-30 min, adding citric acid and a polymerization initiator, raising the temperature to 80-95 ℃, and reacting for 30-45 min to obtain the first modified layer coating.

The preparation steps of the second modified layer are as follows: and (3) placing the nano silicon dioxide, the aluminum hydroxide, the ethyl acetate and the polyglycerol fatty acid ester into a reaction vessel, placing the reaction vessel at the temperature of 75-90 ℃, and reacting for 35-50 min to obtain the second modified layer coating.

The preparation steps of the protective film are as follows: preheating the prepared substrate layer, coating a first modified layer coating on the lower surface of the substrate layer when the substrate layer is heated to 45-55 ℃, and reacting at 85-95 ℃ for 0.5-1.5 h to form a first modified layer; and coating a second modified layer coating on the lower surface of the first modified layer, reacting at 85-95 ℃ for 0.5-1.5 h to form a second modified layer, cooling, and cutting to obtain the protective film.

Example 2

The preparation method of the biodegradable protective film comprises a base material layer, a first modified layer and a second modified layer which are sequentially arranged from top to bottom, wherein the base material layer comprises the following components in parts by weight: 35 parts of glucan, 27 parts of hyaluronic acid, 19 parts of chondroitin sulfate, 16 parts of methyl polyglycerol fatty acid ester tridecyl ester and 21 parts of additive, wherein the first modified layer comprises the following components in parts by weight: 42 parts of polybutylene succinate, 31 parts of polylactic acid, 20 parts of polyvinyl alcohol, 13 parts of citric acid and 9 parts of azodiisobutyronitrile serving as a polymerization initiator, wherein the second modification layer comprises the following components in parts by weight: 28 parts of nano silicon dioxide, 21 parts of aluminum hydroxide, 13 parts of ethyl acetate and 8 parts of polyglycerol fatty acid ester.

Wherein the additive comprises the following components in percentage by mass: 4: 3 of methanol, trifluoroacetic acid and sodium silicate, the preparation steps of the additive are as follows: dividing methanol into two equal parts, adding weighed trifluoroacetic acid, sodium silicate and the first part of methanol into a reaction container, and continuously stirring for 15-25 min to obtain the additive.

The preparation steps of the substrate layer are as follows: putting required amounts of dextran, hyaluronic acid, chondroitin sulfate and methyl polyglycerol fatty acid ester tridecyl ester into a reaction container, wherein the initial temperature of the reaction container is 50-60 ℃, adding all raw materials, keeping heating while continuously stirring, keeping the heating rate at 2-3 ℃/min, continuously stirring and mixing for 10-15 min, slowly adding an additive, continuously stirring until the additive is added, slowly adding a second part of methanol, and continuously stirring until the methanol is added to obtain a mixture; putting the mixture into a double-screw extruder for mixing and melting to obtain a mixed material, cooling after mixing is finished, and granulating after cooling to room temperature; and (3) drying the obtained particles in drying equipment, and then placing the particles in a film blowing machine for film blowing to obtain a substrate layer.

The first modified layer was prepared as follows: placing polybutylene succinate, polylactic acid and polyvinyl alcohol into a reaction vessel, reacting at 65-70 ℃ for 20-30 min, adding citric acid and a polymerization initiator, raising the temperature to 80-95 ℃, and reacting for 30-45 min to obtain the first modified layer coating.

The preparation steps of the second modified layer are as follows: and (3) placing the nano silicon dioxide, the aluminum hydroxide, the ethyl acetate and the polyglycerol fatty acid ester into a reaction vessel, placing the reaction vessel at the temperature of 75-90 ℃, and reacting for 35-50 min to obtain the second modified layer coating.

The preparation steps of the protective film are as follows: preheating the prepared substrate layer, coating a first modified layer coating on the lower surface of the substrate layer when the substrate layer is heated to 45-55 ℃, and reacting at 85-95 ℃ for 0.5-1.5 h to form a first modified layer; and coating a second modified layer coating on the lower surface of the first modified layer, reacting at 85-95 ℃ for 0.5-1.5 h to form a second modified layer, cooling, and cutting to obtain the protective film.

Example 3

The preparation method of the biodegradable protective film comprises a base material layer, a first modified layer and a second modified layer which are sequentially arranged from top to bottom, wherein the base material layer comprises the following components in parts by weight: 25 parts of glucan, 22 parts of hyaluronic acid, 17 parts of chondroitin sulfate, 15 parts of methyl polyglycerol fatty acid ester tridecyl ester and 19 parts of additive, wherein the first modified layer comprises the following components in parts by weight: 37 parts of polybutylene succinate, 28 parts of polylactic acid, 17 parts of polyvinyl alcohol, 12 parts of citric acid and 8 parts of a polymerization initiator, wherein the polymerization initiator is one of benzoyl peroxide, azobisisobutyronitrile and tert-butyl peroxybenzoate. The second modified layer comprises the following components in parts by weight: 26 parts of nano silicon dioxide, 18 parts of aluminum hydroxide, 12 parts of ethyl acetate and 6 parts of polyglycerol fatty acid ester.

Wherein the additive comprises the following components in percentage by mass: 3: 2, and sodium silicate, the preparation steps of the additive are as follows: dividing methanol into two equal parts, adding weighed trifluoroacetic acid, sodium silicate and the first part of methanol into a reaction container, and continuously stirring for 15-25 min to obtain the additive.

The preparation steps of the substrate layer are as follows: putting required amounts of dextran, hyaluronic acid, chondroitin sulfate and methyl polyglycerol fatty acid ester tridecyl ester into a reaction container, wherein the initial temperature of the reaction container is 50-60 ℃, adding all raw materials, keeping heating while continuously stirring, keeping the heating rate at 2-3 ℃/min, continuously stirring and mixing for 10-15 min, slowly adding an additive, continuously stirring until the additive is added, slowly adding a second part of methanol, and continuously stirring until the methanol is added to obtain a mixture; putting the mixture into a double-screw extruder for mixing and melting to obtain a mixed material, cooling after mixing is finished, and granulating after cooling to room temperature; and (3) drying the obtained particles in drying equipment, and then placing the particles in a film blowing machine for film blowing to obtain a substrate layer.

The first modified layer was prepared as follows: placing polybutylene succinate, polylactic acid and polyvinyl alcohol into a reaction vessel, reacting at 65-70 ℃ for 20-30 min, adding citric acid and a polymerization initiator, raising the temperature to 80-95 ℃, and reacting for 30-45 min to obtain the first modified layer coating.

The preparation steps of the second modified layer are as follows: and (3) placing the nano silicon dioxide, the aluminum hydroxide, the ethyl acetate and the polyglycerol fatty acid ester into a reaction vessel, placing the reaction vessel at the temperature of 75-90 ℃, and reacting for 35-50 min to obtain the second modified layer coating.

The preparation steps of the protective film are as follows: preheating the prepared substrate layer, coating a first modified layer coating on the lower surface of the substrate layer when the substrate layer is heated to 45-55 ℃, and reacting at 85-95 ℃ for 0.5-1.5 h to form a first modified layer; and coating a second modified layer coating on the lower surface of the first modified layer, reacting at 85-95 ℃ for 0.5-1.5 h to form a second modified layer, cooling, and cutting to obtain the protective film.

Comparative example 1

This comparative example is similar to the preparation procedure in example 1 except that the protective film has only the base material layer and does not have the first modified layer and the second modified layer.

Comparative example 2

This comparative example is similar to the preparation procedure in example 1 except that the substrate layer of the protective film has no additive.

Comparative example 3

The common degradable protective film sold in the market is selected for the comparative example.

Performance test

Taking the protective films in example 1, example 2, example 3, comparative example 1, comparative example 2 and comparative example 3 as test samples, respectively, testing the tensile strength and the elongation at break of each sample by referring to the standard GB/T1040.3-2006, taking a proper amount of the samples to be placed in humid soil at normal temperature, and recording the mass loss rate of the test samples after 30 days and 60 days as degradability, wherein the test results are shown in the following table:

from the table above, the tensile strength, elongation at break and degradation performance of the protective films prepared in examples 1-3 are all obviously higher than those of comparative example 3, which shows that the preparation method of the invention improves the service strength and degradation performance of the protective films. The tensile strength and elongation at break of comparative example 1 were reduced compared to example 1, indicating that the first modified layer and the second modified layer of the present invention effectively improve the service strength of the protective film. Compared with the example 1 and the comparative example 2, the tensile degradation performance is obviously reduced, which shows that intramolecular and intermolecular hydrogen bonds are formed among the glucan, the hyaluronic acid and the chondroitin sulfate in the comparative example 2, the hydrogen bonds influence the melting process and reduce the performance of preparing the base material layer, so that the additive effectively promotes the melting process of preparing the base material layer.

The foregoing illustrates and describes the principles, general features, and advantages of the present invention. It should be understood by those skilled in the art that the above embodiments do not limit the present invention in any way, and all technical solutions obtained by using equivalent alternatives or equivalent variations fall within the scope of the present invention.