阅读说明：本技术 一种可降解变色材料及其制备方法 (Degradable color-changing material and preparation method thereof ) 是由 李盈 兰翠芹 吴婧乙 于 2020-03-27 设计创作，主要内容包括：本发明提供了一种可降解变色材料及其制备方法,所述可降解变色材料包括如下质量份数的组分：淀粉20-40份、增塑剂10-20份、乙酸10-20份、粘合剂14-56份、变色油墨25-81份。本发明通过在淀粉中引入增塑剂、醋酸、粘合剂以及变色油墨,使得在淀粉变性过程中与变色油墨结合,形成可塑性的变色材料；这样利用淀粉代替衍生于石化资源的基材,使得该变色材料能够被生物降解,对环境友好,实现资源合理利用的同时,降低了变色材料的生产成本；且变色材料的颜色能随外界条件的变化而呈现出动态变化效果,迎合了人们对复合材料求新、求个性化及功能化的消费心理,使变色材料在装饰领域有了全新的发展。(The invention provides a degradable color-changing material and a preparation method thereof, wherein the degradable color-changing material comprises the following components in parts by mass: 20-40 parts of starch, 10-20 parts of plasticizer, 10-20 parts of acetic acid, 14-56 parts of adhesive and 25-81 parts of color-changing ink. The invention leads the plasticizer, the acetic acid, the adhesive and the color-changing printing ink into the starch, so that the starch is combined with the color-changing printing ink in the modification process of the starch to form a plastic color-changing material; the starch is used for replacing a base material derived from petrochemical resources, so that the color-changing material can be biodegraded, is environment-friendly, realizes reasonable utilization of resources and reduces the production cost of the color-changing material; and the color of the color-changing material can show a dynamic change effect along with the change of external conditions, thus meeting the consumption psychology of people for seeking novelty, individuation and functionalization of the composite material and leading the color-changing material to have brand new development in the decoration field.)

1. The degradable color-changing material is characterized by comprising the following components in parts by mass: 20-40 parts of starch, 10-20 parts of plasticizer, 10-20 parts of acetic acid, 14-56 parts of adhesive and 25-81 parts of color-changing ink.

2. The degradable color-changing material of claim 1, wherein the binder comprises one or more of marshmallow, gelatin, and acacia.

3. The degradable color-changing material of claim 1, wherein the plasticizer comprises one of ethylene glycol, glycerol, and an amino-containing compound, wherein the amino-containing compound comprises one or more of urea and formamide.

4. The degradable color-changing material of claim 1 wherein the starch comprises one or more of corn starch, wheat starch, potato starch, tapioca starch, soluble starch and dextrin pregelatinized starch.

5. The degradable color-changing material according to claim 1, wherein the color-changing ink comprises one or more of a temperature-sensitive color-changing ink, an ultraviolet-fluorescent color-changing ink, an infrared-excited color-changing ink, a water-sensitive color-changing ink, an optical color-changing ink, a microcapsule fragrance ink, and a noctilucent color-changing ink.

6. A method for preparing a degradable color-changing material, the degradable color-changing material according to any one of claims 1 to 5 being prepared, the method comprising:

adding starch, a plasticizer and acetic acid into water, and uniformly stirring to form a mixture A;

adding a binder into the mixture A, heating and stirring in a water bath at 80-100 ℃ to form a mixture B;

and after the mixture B is cooled to 45-55 ℃, adding color-changing ink, uniformly stirring to form a mixture C, pouring the mixture C into a mold, heating for curing, drying, and demolding to obtain the degradable color-changing material.

7. The method for preparing the degradable color-changing material according to claim 6, wherein the mass ratio of the starch, the plasticizer, the acetic acid and the water is: (1.8-2.2): (0.8-1.2): (0.8-1.2): (9-11).

8. The method for preparing the degradable color-changing material according to claim 7, wherein the mass ratio of the adhesive to the mixture A is (1-2): 10.

9. the method for preparing the degradable color-changing material according to claim 8, wherein the mass ratio of the color-changing ink to the mixture B is (0.8-1.2): 5.

10. the method for preparing the degradable color-changing material according to claim 6, wherein the heating curing, drying and demolding comprise:

and (3) placing the mold filled with the mixture C into an electric heating air blowing drying oven, curing at the temperature of 75-85 ℃, air-drying for 6-7 hours, then opening the mold and taking out a sample, wherein the sample is the degradable color-changing material.

Technical Field

The invention relates to the technical field of color-changing materials, in particular to a degradable color-changing material and a preparation method thereof.

Background

The phenomenon of color change refers to a change of a substance in response to light under the action of an external environment, and the phenomenon generally exists in the nature. The phenomenon that a substance or a system undergoes a significant change in color under the action of an external excitation source (light, heat, electricity, etc.) is called discoloration, and devices made using the discoloration of a material are called discoloration materials.

Over the past 50 to 60 years, the development of color-changing materials based on petroleum-based synthetic polymers has been rapidly progressing, such as: the color-changing material is used for military affairs, so that the military uniform changes color along with the surrounding environment; the Nippon rayon company develops color-changeable clothes by using photochromic materials, and the color of the clothes is changed by the irradiation of ultraviolet rays; most of the color-changing materials are made of photochromic dyes, so that fibers are printed and dyed by a coloring technology. However, most of the color-changing materials are obtained through petrochemical approaches, petroleum-based high polymer materials are used as nonrenewable resources, the natural degradation speed is too slow, and the soil structure and the performance can be damaged when the color-changing materials are buried in the soil.

Disclosure of Invention

The invention aims to solve the problem of how to provide a degradable color-changing material to a certain extent, thereby improving the environmental friendliness of the color-changing material.

In order to solve the problems, the invention provides a degradable color-changing material which comprises the following components in parts by mass: 20-40 parts of starch, 10-20 parts of plasticizer, 10-20 parts of acetic acid, 14-56 parts of adhesive and 25-81 parts of color-changing ink.

Optionally, the binder comprises one or more of marshmallow, gelatin, and acacia.

Optionally, the plasticizer comprises one of ethylene glycol, glycerol, or an amino-containing compound, wherein the amino-containing compound comprises one or more of urea and formamide.

Optionally, the starch comprises one or more of corn starch, wheat starch, potato starch, tapioca starch, soluble starch, and dextrin pregelatinized starch.

Optionally, the color-changing ink comprises one or more of temperature-sensitive color-changing ink, ultraviolet light-sensitive color-changing ink, ultraviolet fluorescence color-changing ink, infrared excitation color-changing ink, water-sensitive color-changing ink, optical color-changing ink, microcapsule fragrant ink and noctilucent color-changing ink.

The invention also aims to provide a preparation method of the degradable color-changing material, which aims to improve the environmental friendliness of the color-changing material by using the degradable color-changing material.

In order to achieve the purpose, the technical scheme of the invention is realized as follows:

a preparation method of a degradable color-changing material comprises the following steps:

adding starch, a plasticizer and acetic acid into water, and uniformly stirring to form a mixture A;

adding a binder into the mixture A, heating and stirring in a water bath at 80-100 ℃ to form a mixture B;

and after the mixture B is cooled to 45-55 ℃, adding color-changing ink, uniformly stirring to form a mixture C, pouring the mixture C into a mold, heating for curing, drying, and demolding to obtain the degradable color-changing material.

Optionally, the mass ratio of the starch, the plasticizer, the acetic acid and the water is: (1.8-2.2): (0.8-1.2): (0.8-1.2): (9-11).

Optionally, the mass ratio of the binder to the mixture a is (1-2): 10.

optionally, the mass ratio of the color-changing ink to the mixture B is (0.8-1.2): 5.

optionally, the heat curing, dry demolding comprises: and (3) placing the mold filled with the mixture C into an electric heating air blowing drying oven, curing at the temperature of 75-85 ℃, air-drying for 6-7 hours, then opening the mold and taking out a sample, wherein the sample is the degradable color-changing material.

Compared with the prior art, the degradable color-changing material and the preparation method thereof provided by the invention have the following advantages:

(1) the invention leads plasticizer, acetic acid, adhesive and color-changing printing ink into starch, so that the starch is combined with the color-changing printing ink in the starch modification process to form a plastic color-changing material; the starch is used for replacing a base material derived from petrochemical resources, so that the color-changing material can be biodegraded, is environment-friendly, realizes reasonable utilization of resources and reduces the production cost of the color-changing material; and the color of the color-changing material can show a dynamic change effect along with the change of external conditions, so that the material is endowed with dynamic inspiration visual impact, and the consumption psychology of people for seeking novelty, individuation and functionalization of the composite material is met, so that the color-changing material has brand new development in the decoration field.

(2) The preparation method is simple in preparation process, the starch adopted by the preparation method can be biodegraded, the source is rich, the price is low, the problems of difficult dissolution and difficult dissolution of corn starch can be solved by adding the glycerol and the water, the starch is plasticized, the acetic acid can further perform the plasticizing and toughening effects, the reaction uniformity is improved by the adhesive, the mechanical property of the color-changing material is enhanced, and the method is suitable for large-scale production.

Drawings

FIG. 1 is a schematic diagram illustrating a color change process of a degradable color-changing material according to an embodiment of the present invention;

FIG. 2 is a flow chart of a method for preparing a degradable color-changing material according to an embodiment of the invention;

fig. 3 is a drawing graph of a degradable color-changing material according to an embodiment of the invention.

Detailed Description

It should be noted that the embodiments and features of the embodiments of the present invention may be combined with each other without conflict.

In addition, the terms "comprising," "including," "containing," and "having" are intended to be non-limiting, i.e., that other steps and other ingredients can be added that do not affect the results. Unless otherwise specified, materials, equipment and reagents are commercially available.

In addition, although the invention has described the forms of S1, S2, S3 and the like for each step in the preparation, the description is only for the convenience of understanding, and the forms of S1, S2, S3 and the like do not represent the limitation of the sequence of each step.

In the Vietnam war period of 1970, the color-changing material is applied to military by the United states department of defense and serves as a 'invisible' military uniform to achieve the purpose of camouflage; in the eighties of the twentieth century, after the war is over, Japan has been forced to research color-changing materials, so that the color-changing materials enter the daily life of people, and Nintendo Nippon rayon company develops color-changing clothes called YiUV silk by using photosensitive color-changing materials; after twenty-first century, the company Jialibao, Japan, developed photochromic microcapsule dyes which change the color of the dyes by absorbing ultraviolet rays, can print patterns on fibers, and made photochromic material fabrics; in addition, the color-changing material can also be applied to specific parts of certain trademarks, for example, the technology of 'ultraviolet invisible character patterns', 'temperature change identification' or 'hand feeling three-dimensional characters' can be used for realizing the identification of true and false through a currency detector or a hand feeling. However, the inventor finds that the development path of the color-changing material focuses on how to better realize the color change and how to better combine the color-changing ink with the substrate, and little concern is about whether the color-changing material can be degraded or not. However, most of the existing color-changing materials are polymer materials obtained through petrochemical processes, and have many disadvantages, such as limited resources, difficult degradation, ecological system threat, and environmental burden aggravation, so that research and development of renewable biodegradable color-changing materials are urgent.

It can be known that starch is a natural polymer material with abundant sources and low price, and is also an inexhaustible renewable resource, which can be biodegraded under various environmental conditions, and the final degradation products, namely carbon dioxide and water, can be recycled through photosynthesis of plants without causing any pollution to the environment, so that starch is highly valued by people in the fields of agriculture, industry, science and technology and the like. If degradable starch is used as a raw material to prepare the color-changing material, a new idea can be provided for realizing the resource utilization of the starch.

In order to solve the problems, the invention provides a degradable color-changing material, which is prepared by adding color-changing ink into a base material taking starch as a raw material, and the main material of the color-changing material is degradable starch, so that on one hand, the color of the color-changing material can show a dynamic change effect along with the change of external conditions, and on the other hand, the color-changing material is simple and easy to obtain, the cost of the color-changing material is reduced, and the color-changing material can be degraded and regenerated, meets the green environmental protection requirement advocated by the modern society, is easier to accept by consumers, and has better market application value.

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.

Referring to fig. 1, an embodiment of the present invention provides a degradable color-changing material, including the following components in parts by weight: 20-40 parts of starch, 10-20 parts of plasticizer, 10-20 parts of acetic acid, 14-56 parts of adhesive and 25-81 parts of color-changing ink.

Therefore, the plasticizer and the acetic acid are added into the starch to reduce the intermolecular force of the starch, so that the starch shows fluidity, and then the starch is mixed with the color-changing ink under the action of the binder and is solidified to form the degradable color-changing material. Fig. 1a is the degradable color-changing material provided by the invention, fig. 1b is the degradable color-changing material which changes color after external stimulation, because the raw materials are easily available, the cost is low, and the material is biodegradable, the pollution problem of petroleum-based materials can be effectively relieved, and meanwhile, the starch is white solid and is easy to develop color, so the color development performance of the color-changing ink can be further enhanced.

Wherein the starch comprises one or more of corn starch, wheat starch, potato starch, tapioca starch, soluble starch and dextrin pregelatinized starch.

It is understood that starch is a natural macromolecule containing hydroxyl groups, the intermolecular hydroxyl-hydrogen bonding action is strong, the starch molecule is composed of two molecules of amylose and amylopectin, and the proportion of amylose and amylopectin is related to the origin from different origins (e.g., difference in longitude and latitude) and categories (e.g., difference in potato and corn species). The starch with higher straight chain content has higher crystallinity, and the high crystallinity causes no melting process in the heating process of the starch, so the modification difficulty is larger. Therefore, the degradable color-changing material provided by the invention comprises starch which is preferably starch with lower amylose content, and further is corn starch with lower amylose content.

In addition, starch has low elongation at break and poor processing fluidity, is not easily processed and used alone, and cannot obtain properties of flowing and deforming when heated and maintaining a certain shape after cooling unless the original structure is changed, that is, cannot be used as a base material of a color-changing material.

In the embodiment of the invention, the plasticizer is added into the starch, and the active groups on the plasticizer and the hydroxyl groups on the starch are utilized to perform hydrogen bond reaction, so that the intermolecular force of the starch is reduced. Wherein, the plasticizer can be glycol, glycerol or amino-containing compounds such as urea, formamide and the like.

In the degradable color-changing material provided by the invention, preferably, the plasticizer is glycerol (glycerol), the glycerol can also be degraded in microorganisms, and the glycerol can be used as a carbon source generated by the microorganisms. The interaction of hydroxyl on the glycerol and polar groups of the starch greatly weakens hydrogen bonds among starch molecules, large molecules can move at a lower temperature, and the purpose of lowering the melting temperature is achieved.

In addition, the degradable color-changing material provided by the invention also comprises acetic acid, on one hand, the acetic acid can react with hydroxyl in starch macromolecules under certain conditions to obtain acetate starch, and the acetate starch introduces a small amount of ester groups into starch molecules, so that intermolecular association of amylose is prevented or reduced, and the processing stability of the starch is improved; on the other hand, acetic acid and glycerol can form acetin, and the acetin can also be used as a plasticizer to improve the mechanical property of the starch, so that the structural stability of the degradable color-changing material is enhanced.

The adhesive has the main function of improving the compatibility of the starch and the color-changing printing ink, thereby enhancing the mechanical property of the degradable color-changing material. In embodiments of the invention, the binder comprises one or more of marshmallow, gelatin and gum arabic, preferably the binder is marshmallow. The cotton candy is low in cost and easy to obtain, is mainly prepared from corn syrup, gelatin and Arabic gum, and has better compatibility with starch compared with the pure gelatin and Arabic gum.

The color-changing ink in the embodiment of the invention comprises one or more of temperature-sensitive color-changing ink, ultraviolet photosensitive color-changing ink, ultraviolet fluorescent color-changing ink, infrared excitation color-changing ink, water color-changing ink, optical color-changing ink, microcapsule fragrance ink and noctilucent color-changing ink.

Therefore, color-changing ink with different properties can be added according to actual requirements, so that different use effects are achieved. For example, the thermochromic ink is added, so that the color-changing material can show a certain specific color at normal temperature, the color disappears and becomes colorless after being heated, and the original color is immediately recovered after being cooled; or colorless at room temperature, changing into another color after heating, and recovering to original colorless after cooling; or by adding the photosensitive color-changing ink, color change occurs when the color-changing material meets sunlight or ultraviolet light.

According to the embodiment of the invention, the plasticizer, the acetic acid, the adhesive and the color-changing ink are introduced into the starch, so that the starch is combined with the color-changing ink in the starch modification process to form a plastic color-changing material; the starch is used for replacing a base material derived from petrochemical resources, so that the color-changing material can be biodegraded, is environment-friendly, realizes reasonable utilization of resources and reduces the production cost of the color-changing material; and the color of the color-changing material can show a dynamic change effect along with the change of external conditions, so that the material is endowed with dynamic inspiration visual impact, and the consumption psychology of people for seeking novelty, individuation and functionalization of the composite material is met, so that the color-changing material has brand new development in the decoration field.

Referring to fig. 2, another embodiment of the present invention provides a method for preparing the degradable color-changing material, which specifically includes the steps of:

s1, adding starch, a plasticizer and acetic acid into water, and stirring uniformly to form a mixture A;

s2, adding a binder into the mixture A to form a mixture B, and heating and stirring the mixture B in a water bath at the temperature of 80-100 ℃ until the mixture B is viscous;

s3, cooling to 45-55 ℃, adding the color-changing ink, uniformly stirring to form a mixture C, pouring the mixture C into a mold, heating for curing, drying, and demolding to obtain the degradable color-changing material.

Specifically, in step S1, starch, plasticizer, acetic acid, and water are mixed at a mass ratio (1.8-2.2): (0.8-1.2): (0.8-1.2): (9-11) mixing, and stirring uniformly to form a mixture A.

Wherein the starch comprises one or more of corn starch, wheat starch, potato starch, tapioca starch, soluble starch and dextrin pregelatinized starch; the plasticizer comprises one of ethylene glycol, glycerol or an amino-containing compound, wherein the amino-containing compound comprises one or more of urea and formamide.

The addition of the plasticizer, acetic acid and water can improve the problems of difficult dissolution and infusibility of the starch, and plays a role in plasticizing the corn starch.

In step S2, the mass ratio of the binder to the mixture a is (1-2): 10. wherein the binder comprises one or more of marshmallow, gelatin, and acacia.

The adhesive can effectively promote the mixing uniformity among the plasticizer, the starch and the color-changing printing ink, under the external physical factors of temperature rise and mixing, the plasticizer permeates and destroys the original crystalline structure of starch granules, the hydrogen bond action among starch molecules is weakened, the molecular chain motion is intensified, the glass transition temperature of the molecular chain is reduced, and finally the disordered continuous phase of the starch molecular chain is formed, so that the thermoplastic processing process is realized. Meanwhile, due to the movement flexibility of micromolecules of the plasticizer, the generation of starch crystalline state is inhibited, and the starch and the gelatin are subjected to cross-linking action, so that the mechanical property of the prepared color-changing material is improved.

In step S3, the mass ratio of the color-changing ink to the mixture B is (0.8 to 1.2): 5. the mixture B is cooled to 45-55 ℃, and then the color-changing ink is added, so that complete reaction of starch, plasticizer, acetic acid and gelatin is avoided, and the color-changing ink is added after the reaction temperature is reduced because certain temperature conditions (80-100 ℃) are required for modification crosslinking reaction among the gelatin, the plasticizer and the starch, so that the dispersibility of the color-changing ink in the base material can be enhanced.

The heating curing, drying and demoulding in the step 3 comprises the following steps: and (3) placing the mold filled with the mixture C into an electric heating air blast drying oven, curing at the temperature of 75-85 ℃, air-drying for 6-7 hours, then opening the mold and taking out a sample, wherein the sample is the degradable color-changing material.

After the color-changing ink is added at the temperature of 45-55 ℃, the mixture C is cured at the temperature of 75-85 ℃, so that the color-changing ink and the starch substrate can be fully mixed and uniformly dispersed in a network structure formed by the starch, the plasticizer and the gelatin, and the color-changing material further plays a role in strengthening and toughening on the basis of ensuring the color-changing effect of the color-changing material, and improves the mechanical property of the degradable color-changing material.

Therefore, the starch adopted by the preparation method can be biodegraded, the source is rich, the price is low, the problems of difficult dissolution and difficult dissolution of the corn starch can be solved by adding the glycerol and the water, the starch is plasticized, the acetic acid can further play a role in plasticization and toughening, the adhesive improves the reaction uniformity, and the mechanical property of the color-changing material is enhanced; simple process and is suitable for large-scale production.

The invention will be further illustrated with reference to the following specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. The following examples are examples of experiments where no specific conditions are indicated, generally according to the conditions suggested by the manufacturer. Unless otherwise indicated, percentages and parts are by weight. Wherein, in the embodiment, the starch is corn starch, and the plasticizer is glycerol.