CN111730839A - PE film and preparation method thereof - Google Patents

Abstract

The invention discloses a PE film and a preparation method thereof, and relates to the technical field of packaging bags. The technical key points of the method comprise an inner layer, an intermediate layer and an outer layer which are sequentially overlapped; the inner layer comprises 10 to 45 weight percent of low density polyethylene, 50 to 85 weight percent of linear low density polyethylene and 3 to 10 weight percent of myrcene; the middle layer comprises 10 to 45 weight percent of low density polyethylene, 50 to 85 weight percent of linear low density polyethylene, 1 to 5 weight percent of myrcene and 2 to 10 weight percent of aroma locking agent; the outer layer consists of 10 to 50 weight percent of low density polyethylene and 50 to 90 weight percent of linear low density polyethylene; the fragrance locking agent in the middle layer comprises the following components in parts by weight: 5-15 parts of myrcene; 30-40 parts of ethyl acetate; 40-60 parts of aloe gel, which has the advantages of greatly prolonging the fragrance maintaining time of the PE film, enabling the fragrance to act on consumers and enabling the value of the packaging material to be improved.

Description

PE film and preparation method thereof

Technical Field

The invention relates to the technical field of packaging bags, in particular to a PE film and a preparation method thereof.

Background

The PE film is generally formed by co-extruding an outer layer, a middle layer and an inner layer, and because the PE film is flexible, transparent and has good heat sealing properties, the PE film is widely used for packaging various goods, such as clothing, school supplies, home textiles and the like.

In chinese patent No. CN101480861B, a PE film is disclosed, comprising: the inner layer, the middle layer and the outer layer are sequentially overlapped, and the inner layer comprises 10-45 wt% of low-density polyethylene, 50-85 wt% of linear low-density polyethylene and 3-10 wt% of myrcene; the middle layer comprises 10-45 wt% of low density polyethylene, 50-85 wt% of linear low density polyethylene and 3-10 wt% of myrcene; the outer layer comprises 10 wt% -50 wt% of low density polyethylene and 50 wt% -90 wt% of linear low density polyethylene.

Similar to the above mentioned PE film, the prior art adds a certain proportion of the flavoring agent myrcene into the PE film product formulation, and after processing and forming, the film has a specific and suitable flavor. However, the applicant conducted experiments based on the examples of the above invention, and found that the fragrance-maintaining time of the above invention could only reach 92 hours at the maximum.

Since the PE film is produced by a manufacturer and used for packaging goods in downstream enterprises, a series of processes such as warehousing, ex-warehouse, using and the like of the PE film are required, and the processes require a certain time, the PE film easily loses fragrance before being ex-warehouse or loses fragrance before being packaged and sold, and the fragrance of the PE film cannot act on consumers due to the retention time period of the fragrance of the PE film, so that the value of the packaged goods cannot be improved.

Therefore, a new solution is needed to solve the above problems.

Disclosure of Invention

In view of the disadvantages of the prior art, an object of the present invention is to provide a PE film having the advantages of greatly increasing the fragrance retention time of the PE film, enabling the fragrance to act on the consumer, and enabling the value of the package to be increased.

The second purpose of the invention is to provide a preparation method of a PE film, which has the advantages of greatly prolonging the fragrance retention time of the PE film, enabling fragrance to act on consumers and enabling the value of a package to be improved.

In order to achieve the first purpose, the invention provides the following technical scheme:

a PE film comprises an inner layer, a middle layer and an outer layer which are sequentially superposed;

the inner layer comprises 10 to 45 weight percent of low density polyethylene, 50 to 85 weight percent of linear low density polyethylene and 3 to 10 weight percent of myrcene;

the middle layer comprises 10-45 wt% of low density polyethylene, 50-85 wt% of linear low density polyethylene, 1-5 wt% of myrcene and 2-10 wt% of aroma locking agent;

the outer layer consists of 10 to 50 weight percent of low density polyethylene and 50 to 90 weight percent of linear low density polyethylene;

the fragrance locking agent in the middle layer comprises the following components in parts by weight:

5-15 parts of myrcene;

30-40 parts of ethyl acetate;

40-60 parts of aloe gel.

By adopting the technical scheme, the inner layer provides primary fragrance, the middle layer is used for supplementing fragrance, and the outer layer is used as a composite base layer of other materials. Wherein, the fragrance locking agent in the middle layer plays the roles of locking fragrance and delaying fragrance emission: firstly, the myrcene is dissolved in ethyl acetate to reduce the concentration of myrcene, so that the volatility of myrcene during blow molding is reduced, and the fragrance of myrcene can be kept in the middle layer in a larger amount after the blow molding is finished.

And then, myrcene, ethyl acetate and aloe gel are mixed and dried to form a dry gel mixture, at the moment, myrcene and ethyl acetate are contained in the dry gel, the fragrance of myrcene is not easy to escape from the gel, and the slow storage amount of myrcene in the middle layer before the PE film is delivered out of a warehouse can be ensured.

With the time being prolonged, the residual ethyl acetate in the middle layer can gradually volatilize in the air, so that a channel for volatilizing myrcene is generated on the surface of the aloe gel, and the fragrance is supplemented after the fragrance of myrcene in the inner layer is lost; meanwhile, with the volatilization of ethyl acetate, the channels on the surface of the xerogel are more and more, and at the moment, myrcene can be fully volatilized, so that the fragrance supplementation efficiency is ensured.

Finally, the ethyl acetate is non-toxic and can generate fragrance while volatilizing, and the fragrance of the ethyl acetate and the fragrance of the myrcene are synergistically acted, so that the fragrance of the PE film is improved. Therefore, the PE film provided by the scheme can still maintain the fragrance for a long time after the PE film is delivered from a warehouse, and acts on consumers, so that the value of the packaging material can be improved.

More preferably, the weight part of myrcene in the aroma-locking agent is 13-15 parts.

By adopting the technical scheme, the retention amount of myrcene after blow molding is improved, and the mechanical property of the middle layer is not influenced.

More preferably, the weight part of the ethyl acetate is 35-40 parts.

By adopting the technical scheme, the amount of ethyl acetate is large, the myrcene is further diluted, the concentration of the myrcene is reduced, the retention amount of the myrcene after blow molding is improved, and the volatility of the myrcene before the PE film is taken out of a warehouse is reduced.

Further preferably, the aloe vera gel is 55-60 parts by weight.

By adopting the technical scheme, the myrcene can be completely coated by the aloe gel, so that the fragrance locking rate of the aloe gel is improved.

More preferably, the inner layer further comprises 1 wt% -2 wt% of an aroma locking agent.

Through adopting above-mentioned technical scheme, the lock incenses agent of inlayer also can slow down the volatilization of myrcene for myrcene's fragrant smell can remain for a longer time.

Further preferably, the fragrance locking agent also comprises 5-10 parts by weight of ethanol.

By adopting the technical scheme, the ethanol is used as the leveling agent, so that the myrcene can be better dispersed in the aloe gel, and the aloe gel can be uniformly dispersed in the middle layer, so that the myrcene is uniformly distributed in the middle layer.

More preferably, the weight part of the ethanol is 8-10 parts.

By adopting the technical scheme, the aloe gel is uniformly dispersed in the middle layer, and the myrcene is uniformly distributed in the middle layer.

In order to achieve the second purpose, the invention provides the following technical scheme:

a preparation method of a PE film comprises the following steps:

step one, mixing myrcene, low-density polyethylene and linear low-density polyethylene in corresponding weight percentages of an inner layer in a kneading machine to obtain inner layer mixed powder; carrying out blow molding on the inner layer mixed powder through an extrusion film blowing system to obtain an inner layer of the PE film;

step two, mixing myrcene, low-density polyethylene, linear low-density polyethylene and aroma locking agent which are corresponding components of the middle layer in a kneading machine to obtain mixed powder of the middle layer; blow molding the mixed powder of the middle layer by an extrusion film blowing system to obtain the middle layer of the PE film;

step three: mixing the low-density polyethylene and the linear low-density polyethylene in the outer layer according to the corresponding weight percentage in a kneading machine to obtain outer layer mixed powder; performing blow molding on the outer layer mixed powder through an extrusion film blowing system to obtain the outer layer of the PE film;

and step four, carrying out dry composite processing on the inner layer obtained in the step one, the intermediate layer obtained in the step two and the outer layer obtained in the step three to obtain the PE film.

Through adopting above-mentioned technical scheme, prepare three-layer individual layer's film in proper order, after compounding the three-layer film afterwards, the inlayer can provide preliminary fragrant smell, and the intermediate level can be as replenishing fragrance, and the skin can be as the compound basic unit of other materials.

In summary, compared with the prior art, the invention has the following beneficial effects:

(1) through adding the fragrance-locking agent in the middle layer, after the blow molding is finished, the fragrance-locking agent in the middle layer plays roles of locking fragrance and delaying fragrance emission: firstly, the myrcene is dissolved in ethyl acetate to reduce the concentration of myrcene, so that the volatility of myrcene during blow molding is reduced, and the fragrance of myrcene can be kept in the middle layer in a larger amount after the blow molding is finished. And then, myrcene, ethyl acetate and aloe gel are mixed and dried to form a dry gel mixture, at the moment, myrcene and ethyl acetate are contained in the dry gel, the fragrance of myrcene is not easy to escape from the gel, and the slow storage amount of myrcene in the middle layer before the PE film is delivered out of a warehouse can be ensured. With the time being prolonged, the residual ethyl acetate in the middle layer can gradually volatilize in the air, so that a channel for volatilizing myrcene is generated on the surface of the aloe gel, and the fragrance is supplemented after the fragrance of myrcene in the inner layer is lost; meanwhile, with the volatilization of ethyl acetate, the channels on the surface of the xerogel are more and more, and at the moment, myrcene can be fully volatilized, so that the fragrance supplementation efficiency is ensured. Finally, the ethyl acetate is non-toxic and can generate fragrance while volatilizing, and the fragrance of the ethyl acetate and the fragrance of the myrcene are synergistically acted, so that the fragrance of the PE film is improved;

(2) by adding the ethanol into the fragrance locking agent, the ethanol can be used as a leveling agent, so that the myrcene can be better dispersed in the aloe gel, and the aloe gel can be uniformly dispersed in the middle layer, so that the myrcene is uniformly distributed in the middle layer.

Detailed Description

The present invention will be described in detail with reference to examples.

Example 1: a PE film comprises an inner layer, a middle layer and an outer layer which are sequentially overlapped.

Wherein, the components and the corresponding weight percentages in the inner layer, the middle layer and the outer layer are shown in table 1, and the preparation method comprises the following steps:

step one, mixing myrcene, low-density polyethylene and linear low-density polyethylene in corresponding weight percentages of an inner layer in a kneading machine to obtain inner layer mixed powder; carrying out blow molding on the inner layer mixed powder through an extrusion film blowing system to obtain an inner layer of the PE film; the rotating speed of the kneading machine in the step is 800-900 r/min;

step two, mixing myrcene, low-density polyethylene, linear low-density polyethylene and aroma locking agent which are corresponding components of the middle layer in a kneading machine to obtain mixed powder of the middle layer; blow molding the mixed powder of the middle layer by an extrusion film blowing system to obtain the middle layer of the PE film; the rotating speed of the kneading machine in the step is 800-900 r/min;

mixing the low-density polyethylene and the linear low-density polyethylene in the outer layer according to the corresponding weight percentage in a kneading machine to obtain outer layer mixed powder; performing blow molding on the outer layer mixed powder through an extrusion film blowing system to obtain the outer layer of the PE film; the rotating speed of the kneading machine in the step is 800-900 r/min;

and step four, carrying out dry composite processing on the inner layer obtained in the step one, the intermediate layer obtained in the step two and the outer layer obtained in the step three to obtain the PE film.

The fragrance-locking agent in the middle layer comprises the following components in parts by weight as shown in table 2, and is prepared by the following steps: putting myrcene, ethyl acetate and aloe vera gel in corresponding parts by weight into a stirring pot, and stirring for 15min at the speed of 200 r/min.

Examples 2 to 5: a PE film, different from example 1 in that the components and their respective parts by weight in the inner layer, intermediate layer and outer layer are as shown in table 1; the components and parts by weight of the aroma-locking agent in the middle layer are shown in table 2.

TABLE 1 compositions and corresponding weight percentages of the inner, middle and outer layers (examples 1 to 5)

TABLE 2 fragrance-locking agent in the middle layer and its parts by weight (examples 1 to 5)

Example 6: a PE film, which is different from the PE film in the embodiment 1, in that when the inner layer is manufactured in the first step, 1 wt% of aroma locking agent is added into the inner layer, and the inner layer comprises 46 wt% of low-density polyethylene, 50 wt% of linear low-density polyethylene, 3 wt% of myrcene and 1 wt% of aroma locking agent; the inner fragrance-locking agent comprises the following components in parts by weight:

15 parts of myrcene;

40 parts of ethyl acetate;

60 parts of aloe gel.

Example 7: a PE film is different from the PE film in example 6 in that 2 wt% of aroma-locking agent is added into the inner layer, and the inner layer comprises 10 wt% of low-density polyethylene, 78 wt% of linear low-density polyethylene, 10 wt% of myrcene and 2 wt% of aroma-locking agent; the inner fragrance-locking agent comprises the following components in parts by weight:

5 parts of myrcene;

30 parts of ethyl acetate;

40 parts of aloe gel.

Example 8: a PE film is different from the PE film in the embodiment 1 in that 5 parts by weight of ethanol is also included in the fragrance-locking agent, and when the fragrance-locking agent is prepared, the ethanol, myrcene, ethyl acetate and aloe vera gel are put into a stirring pot and stirred for 15min under the condition of 200 r/min.

Example 9: a PE film is different from the PE film in the embodiment 1 in that 8 parts by weight of ethanol is also included in the fragrance-locking agent, and when the fragrance-locking agent is prepared, the ethanol, myrcene, ethyl acetate and aloe vera gel are put into a stirring pot and stirred for 15min under the condition of 200 r/min.

Example 10: a PE film is different from the PE film in the embodiment 1 in that the fragrance-locking agent also comprises 10 parts by weight of ethanol, and when the fragrance-locking agent is prepared, the ethanol, myrcene, ethyl acetate and aloe vera gel are put into a stirring pot and stirred for 15min at the speed of 200 r/min.

Example 11: a PE film is different from the PE film in the embodiment 6 in that 5 parts by weight of ethanol is also included in the fragrance-locking agent, and when the fragrance-locking agent is prepared, the ethanol, myrcene, ethyl acetate and aloe vera gel are put into a stirring pot and stirred for 15min under the condition of 200 r/min.

Example 12: a PE film is different from the PE film in the embodiment 6 in that 8 parts by weight of ethanol is also included in the fragrance-locking agent, and when the fragrance-locking agent is prepared, the ethanol, myrcene, ethyl acetate and aloe vera gel are put into a stirring pot and stirred for 15min under the condition of 200 r/min.

Example 13: a PE film is different from the PE film in the embodiment 6 in that the fragrance-locking agent also comprises 10 parts by weight of ethanol, and when the fragrance-locking agent is prepared, the ethanol, myrcene, ethyl acetate and aloe vera gel are put into a stirring pot and stirred for 15min at the speed of 200 r/min.

Comparative example 1: a PE film was obtained according to example 2 of the invention patent publication No. CN 103522699B.

Comparative example 2: a PE film was obtained according to example 4 of the invention patent publication No. CN 103522699B.

Comparative example 3: a PE film is different from the PE film obtained in the example 1 in that no fragrance-locking agent is added in the second step.

Test samples: the PE films obtained in examples 1 to 13 were used as test samples 1 to 13, and the PE films obtained in comparative examples 1 to 3 were used as control samples 1 to 3.

Test one: and (5) testing the performance of the PE film. The test results are shown in table 3.

And (2) test II: randomly arranging 10 testers, evaluating the fragrance maintaining time of the experimental samples 1-13 and the control samples 1-3, and setting the scoring standard as shown in table 4; the average of the scores of 10 testers was taken and the fragrance score data for the PE film is shown in table 5.

TABLE 3 PE film Performance test results

TABLE 4 Scoring standards

TABLE 5 fragrance Scoring data for PE films

And (4) analyzing results: the heat seal strength and the tensile strength at break were not much affected whether or not the fragrance-locking agent was added. Meanwhile, the whole aroma feeling is not influenced by the aroma-locking agent. And at the maintenance time: the retention time of the PE film without the aroma-locking agent can only be 47-92 h, and the aroma retention time of the PE film with the aroma-locking agent can reach 198-433 h, so that the PE film provided by the scheme can still retain the aroma for a long time after the PE film is taken out of a warehouse, acts on consumers, and the value of the packaging material can be improved.

The embodiments of the present invention are preferred embodiments of the present invention, and the scope of the present invention is not limited by these embodiments, so: all equivalent changes made according to the structure, shape and principle of the invention are covered by the protection scope of the invention.

Claims (8)

1. A PE film is characterized by comprising an inner layer, a middle layer and an outer layer which are sequentially superposed;

the inner layer comprises 10 to 45 weight percent of low density polyethylene, 50 to 85 weight percent of linear low density polyethylene and 3 to 10 weight percent of myrcene;

the middle layer comprises 10-45 wt% of low density polyethylene, 50-85 wt% of linear low density polyethylene, 1-5 wt% of myrcene and 2-10 wt% of aroma locking agent;

the outer layer consists of 10 to 50 weight percent of low density polyethylene and 50 to 90 weight percent of linear low density polyethylene;

the fragrance locking agent in the middle layer comprises the following components in parts by weight:

5-15 parts of myrcene;

30-40 parts of ethyl acetate;

40-60 parts of aloe gel.

2. The PE film according to claim 1, wherein the weight part of myrcene in the aroma-locking agent is 13-15 parts.

3. The PE film according to claim 2, wherein the ethyl acetate is 35 to 40 parts by weight.

4. The PE film according to claim 3, wherein the aloe vera gel is 55 to 60 parts by weight.

5. The PE film according to claim 1, wherein the inner layer further comprises 1-2 wt% of a fragrance-locking agent.

6. A PE film according to any one of claims 1 or 5, wherein the fragrance-retaining agent further comprises 5-10 parts by weight of ethanol.

7. A PE film according to claim 5, wherein the ethanol is present in an amount of 8 to 10 parts by weight.

8. A preparation method of a PE film is characterized by comprising the following steps:

step one, mixing myrcene, low-density polyethylene and linear low-density polyethylene in corresponding weight percentages of an inner layer in a kneading machine to obtain inner layer mixed powder; carrying out blow molding on the inner layer mixed powder through an extrusion film blowing system to obtain an inner layer of the PE film;

step two, mixing myrcene, low-density polyethylene, linear low-density polyethylene and aroma locking agent which are corresponding components of the middle layer in a kneading machine to obtain mixed powder of the middle layer; blow molding the mixed powder of the middle layer by an extrusion film blowing system to obtain the middle layer of the PE film;

mixing the low-density polyethylene and the linear low-density polyethylene in the outer layer according to the corresponding weight percentage in a kneading machine to obtain outer layer mixed powder; performing blow molding on the outer layer mixed powder through an extrusion film blowing system to obtain the outer layer of the PE film;

and step four, carrying out dry composite processing on the inner layer obtained in the step one, the intermediate layer obtained in the step two and the outer layer obtained in the step three to obtain the PE film.