阅读说明：本技术 改性海藻酸钠、其制备方法、压敏胶及贴剂 (Modified sodium alginate, preparation method thereof, pressure-sensitive adhesive and patch ) 是由 黄海东 黄振伟 付钦中 于 2021-11-18 设计创作，主要内容包括：本发明提供了一种改性海藻酸钠、其制备方法、压敏胶及贴剂。改性海藻酸钠的制备方法包括：使海藻酸钠与碱液混合,得到海藻酸钠溶液；使海藻酸钠溶液与N-(2-氯乙基)邻苯二甲酰亚胺进行接枝反应,得到改性海藻酸钠。采用上述改性海藻酸钠制得的压敏胶能够获得较好的粘结稳定性和较为适宜的剥离强度。同时由于上述改性海藻酸钠具有很好的亲肤性,因而其应用过程中能够很好地降低皮肤过敏的风险。(The invention provides modified sodium alginate, a preparation method thereof, a pressure-sensitive adhesive and a patch. The preparation method of the modified sodium alginate comprises the following steps: mixing sodium alginate with alkali liquor to obtain sodium alginate solution; and carrying out grafting reaction on the sodium alginate solution and N- (2-chloroethyl) phthalimide to obtain the modified sodium alginate. The pressure-sensitive adhesive prepared from the modified sodium alginate can obtain better bonding stability and more appropriate peel strength. Meanwhile, the modified sodium alginate has good skin-friendly property, so that the risk of skin allergy can be well reduced in the application process.)

1. A preparation method of modified sodium alginate is characterized in that the preparation method of the modified sodium alginate comprises the following steps:

mixing sodium alginate with alkali liquor to obtain sodium alginate solution;

and carrying out grafting reaction on the sodium alginate solution and N- (2-chloroethyl) phthalimide to obtain the modified sodium alginate.

2. The preparation method of modified sodium alginate according to claim 1, wherein in the grafting reaction process, the reaction temperature is 60-80 ℃, and the weight ratio of sodium alginate to N- (2-chloroethyl) phthalimide in the sodium alginate solution is (40-50): 45-55);

preferably, in the grafting reaction process, the reaction temperature is 70-80 ℃, and the weight ratio of the sodium alginate in the sodium alginate solution to the N- (2-chloroethyl) phthalimide is (45-47): (48-52).

3. The preparation method of modified sodium alginate as claimed in claim 1 or 2, wherein in the preparation process of the sodium alginate solution, the alkali solution is sodium hydroxide aqueous solution with the concentration of 5-10 wt%, and the mixing temperature is 50-70 ℃.

4. A modified sodium alginate, which is prepared by the preparation method of the modified sodium alginate as claimed in any one of claims 1 to 3.

5. A pressure-sensitive adhesive comprising the modified sodium alginate of claim 4 and a filler.

6. The pressure-sensitive adhesive according to claim 5, wherein the pressure-sensitive adhesive comprises 10-30 parts by weight of the filler, based on 100 parts by weight of the modified sodium alginate in the pressure-sensitive adhesive;

preferably, the filler is selected from talc;

preferably, the particle size of the filler is 100-300 nm.

7. The pressure-sensitive adhesive according to claim 5 or 6, further comprising 5-15 parts by weight of N-tris (hydroxymethyl) methylamino-2-aminopropanesulfonic acid based on 100 parts by weight of the modified sodium alginate contained in the pressure-sensitive adhesive.

8. A patch comprising a pressure-sensitive adhesive tape composed of a pressure-sensitive adhesive layer and a release film layer, characterized in that the pressure-sensitive adhesive layer is made of the pressure-sensitive adhesive of any one of claims 5 to 7.

9. The patch according to claim 8, wherein said patch is a breathable medical temperature-controlled heat application, comprising a non-woven fabric bag, a heat generating layer disposed inside said non-woven fabric bag, and said pressure-sensitive adhesive tape for fixing said non-woven fabric bag.

10. The patch according to claim 9, wherein the pressure-sensitive adhesive tape has a thickness of 20 to 50 μm.

Technical Field

The invention relates to the field of medical patches, and in particular relates to modified sodium alginate, a preparation method thereof, a pressure-sensitive adhesive and a patch.

Background

The hot compress patch is an external moxibustion patch, and is suitable for warming uterus of puerpera. It has the following effects: consolidating constitution, promoting blood circulation, dispelling blood stasis, warming channels, relieving pain, and expelling cold; regulating qi and blood, improving microcirculation, warming uterus and protecting yin, warming channels and promoting blood circulation, caring ovary, promoting uterine contraction, and regulating female reproductive system.

The hot compress patch generally comprises a non-woven fabric bag, a heating material arranged inside the non-woven fabric bag, and a pressure-sensitive adhesive tape for fixing the non-woven fabric bag. Pressure-sensitive adhesive tapes are a special type of tape made by applying a pressure-sensitive adhesive to a strip-like substrate. Pressure-sensitive adhesives are the most important components of pressure-sensitive adhesive tapes, and serve to impart pressure-sensitive adhesive properties to the tapes. When in use, the adhesive tape is slightly pressed to be adhered to the surface of an adherend.

The peel strength of the pressure-sensitive adhesive directly influences the use effect and use feeling of the hot application, if the peel strength is too small, the phenomenon that the hot application is not attached to the skin or even peels off can occur, and the use effect of the hot application is influenced; if the peel strength is too large, there may be a phenomenon that it is difficult to easily remove the heat application from the skin or that the pressure-sensitive adhesive remains on the skin, which greatly affects the feeling of use of the heat application. In addition, if the skin-friendly property of the pressure-sensitive adhesive is not good, it is likely to cause a skin allergy problem. Therefore, it is of great significance to develop a pressure-sensitive adhesive tape having moderate peel strength and good skin-friendliness.

Disclosure of Invention

The invention mainly aims to provide modified sodium alginate, a preparation method thereof, a pressure-sensitive adhesive and a patch, and aims to solve the problems that the existing patch cannot simultaneously meet the requirements of good skin-friendly property and moderate peel strength.

In order to achieve the above object, the present invention provides a preparation method of modified sodium alginate, which comprises: mixing sodium alginate with alkali liquor to obtain sodium alginate solution; and carrying out grafting reaction on the sodium alginate solution and N- (2-chloroethyl) phthalimide to obtain the modified sodium alginate.

Further, in the grafting reaction process, the reaction temperature is 60-80 ℃, and the weight ratio of sodium alginate to N- (2-chloroethyl) phthalimide in the sodium alginate solution is (40-50) to (45-55); preferably, in the grafting reaction process, the reaction temperature is 70-80 ℃, and the weight ratio of the sodium alginate to the N- (2-chloroethyl) phthalimide in the sodium alginate solution is (45-47) to (48-52).

Further, in the preparation process of the sodium alginate solution, the alkali liquor is a sodium hydroxide aqueous solution, the concentration is 5-10 wt%, and the mixing temperature is 50-70 ℃.

The second aspect of the application also provides modified sodium alginate, and the modified sodium alginate is prepared by the preparation method of the modified sodium alginate.

The third aspect of the application also provides a pressure-sensitive adhesive, which comprises the modified sodium alginate and the filler.

Further, the pressure-sensitive adhesive comprises 10-30 parts by weight of filler based on 100 parts by weight of modified sodium alginate in the pressure-sensitive adhesive; preferably, the filler is selected from talc; preferably, the particle size of the filler is 100 to 300 nm.

Further, the pressure-sensitive adhesive also comprises 5-15 parts by weight of N-tri (hydroxymethyl) methylamino-2-aminopropanesulfonic acid based on 100 parts by weight of modified sodium alginate.

The fourth aspect of the present application also provides a patch comprising a pressure-sensitive adhesive tape composed of a pressure-sensitive adhesive layer and a release film layer, wherein the pressure-sensitive adhesive layer is made of the pressure-sensitive adhesive provided by the present application.

Further, the patch is a breathable medical temperature control hot compress patch, and comprises a non-woven fabric cloth bag, a heating layer arranged inside the non-woven fabric cloth bag, and a pressure sensitive adhesive tape for fixing the non-woven fabric cloth bag.

Further, the thickness of the pressure sensitive adhesive tape is 20-50 μm.

By applying the technical scheme of the invention, sodium alginate is used as a raw material, and N- (2-ethyl) phthalimide is grafted into a molecular structure of alginic acid through a grafting reaction to obtain modified alginic acid; this modified alginic acid is thick form, has very strong viscidity, need not to adopt water or organic solvent to dilute in order to form colloidal state, has avoided conventional adhesive to contain moisture or organic solvent and has the problem that the viscidity reduces or risees after the solvent volatilizees, guarantees the adhesive force and the adhesive stability of the pressure-sensitive adhesive of making. Therefore, the pressure-sensitive adhesive prepared by the modified sodium alginate can obtain better bonding stability and more proper peel strength. Meanwhile, the modified sodium alginate has good skin-friendly property, so that the risk of skin allergy can be well reduced in the application process.

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail with reference to examples.

As described in the background art, the existing patch has a problem that it cannot satisfy both of good skin-friendly property and moderate peel strength. In order to solve the technical problem, the application provides a preparation method of modified sodium alginate, which comprises the following steps: mixing sodium alginate with alkali liquor to obtain sodium alginate solution; and carrying out grafting reaction on the sodium alginate solution and N- (2-chloroethyl) phthalimide to obtain the modified sodium alginate.

Sodium alginate is a by-product obtained by extracting iodine and mannitol from brown algae such as herba Zosterae Marinae or Sargassum, is a natural polysaccharide, and has stability, solubility, viscosity and safety required for medicinal adjuvants. Sodium alginate is soluble in water and insoluble in organic solvents such as ethanol, diethyl ether, chloroform, etc., and has high viscosity, and has been used as thickener, stabilizer, and emulsifier for food. The sodium alginate aqueous solution is viscous but belongs to hydrogel, and when the sodium alginate aqueous solution is exposed to air for use, the viscosity is reduced along with the continuous reduction of the moisture content, so that the sodium alginate aqueous solution cannot be directly used as a pressure-sensitive adhesive for fixing a hot compress patch.

Taking sodium alginate as a raw material, and inoculating N- (2-ethyl) phthalimide into a molecular structure of alginic acid through a grafting reaction to obtain modified alginic acid; this modified alginic acid is thick form, has very strong viscidity, need not to adopt water or organic solvent to dilute in order to form colloidal state, has avoided conventional adhesive to contain moisture or organic solvent and has the problem that the viscidity reduces or risees after the solvent volatilizees, guarantees the adhesive force and the adhesive stability of the pressure-sensitive adhesive of making. Therefore, the pressure-sensitive adhesive prepared by the modified sodium alginate can obtain better bonding stability and more proper peel strength. Meanwhile, the modified sodium alginate has good skin-friendly property, so that the risk of skin allergy can be well reduced in the application process.

The synthetic route of the modified alginic acid is as follows:

the N- (2-ethyl) phthalimide group is introduced to be grafted into the sodium alginate through a grafting reaction, so that the bonding stability and the skin-friendly property of the sodium alginate in the air are greatly improved, and the sodium alginate has better peel strength. In a preferred embodiment, the reaction temperature is 60-80 ℃ during the grafting reaction, and the weight ratio of sodium alginate to N- (2-chloroethyl) phthalimide in the sodium alginate solution is (40-50) to (45-55). The reaction temperature and the raw material ratio in the grafting reaction include but are not limited to the ranges, and the limitation of the reaction temperature and the raw material ratio in the ranges is favorable for further improving the grafting rate of the grafting group in the sodium alginate, so that the bonding stability of the modified sodium alginate in the air is greatly improved, and the proper bonding force of the modified sodium alginate is ensured. In order to further improve the comprehensive performance of the modified sodium alginate, more preferably, in the grafting reaction process, the reaction temperature is 70-80 ℃, and the weight ratio of the sodium alginate to the N- (2-chloroethyl) phthalimide in the sodium alginate solution is (45-47) to (48-52).

In a preferred embodiment, in the preparation process of the sodium alginate solution, the alkali solution is a sodium hydroxide aqueous solution with the concentration of 5-10 wt%, and the mixing temperature is 50-70 ℃. The temperature of the mixing process is limited in the range, so that the mixing uniformity and the mixing speed of the sodium alginate are improved, the concentration of the alkali liquor is limited in the range, the grafting rate of the subsequent grafting reaction is improved, and the adhesive stability of the modified sodium alginate is improved.

The second aspect of the application also provides modified sodium alginate, and the modified sodium alginate is prepared by the preparation method of the modified sodium alginate. Taking sodium alginate as a raw material, and inoculating N- (2-ethyl) phthalimide into a molecular structure of alginic acid through a grafting reaction to obtain modified alginic acid; this modified alginic acid is thick form, has very strong viscidity, need not to adopt water or organic solvent to dilute in order to form colloidal state, has avoided conventional adhesive to contain moisture or organic solvent and has the problem that the viscidity reduces or risees after the solvent volatilizees, guarantees the adhesive force and the adhesive stability of the pressure-sensitive adhesive of making. Therefore, the pressure-sensitive adhesive prepared by the modified sodium alginate can obtain better bonding stability and more proper peel strength. Meanwhile, the modified sodium alginate has good skin-friendly property, so that the risk of skin allergy can be well reduced in the application process.

The third aspect of the application also provides a pressure-sensitive adhesive, which comprises the modified sodium alginate and the filler.

The filler can reduce the using amount of modified sodium alginate in the pressure-sensitive adhesive and reduce the cost, and can adjust the adhesiveness of the pressure-sensitive adhesive, so that the pressure-sensitive adhesive has more proper peel strength and the risk that the pressure-sensitive adhesive is difficult to easily tear or remain on the skin after being used is reduced.

In order to further improve the comprehensive performance of the pressure-sensitive adhesive, the pressure-sensitive adhesive preferably contains 10-30 parts by weight of filler based on 100 parts by weight of modified sodium alginate. More preferably, the filler is selected from talc. Compared with other fillers, the talcum powder has better dispersibility in the modified sodium alginate.

Preferably, the particle size of the filler is 100 to 300 nm. The particle size of the filler includes, but is not limited to, the above range, and it is advantageous to further improve the dispersibility of the filler in the modified sodium alginate.

Although the addition of the coupling agent is beneficial to improving the dispersibility between the filler and the modified sodium alginate, the addition of the coupling agent can influence the adhesive property of the pressure-sensitive adhesive to a certain extent. In order to improve the dispersibility between the filler and the modified sodium alginate and not affect the adhesive property of the pressure-sensitive adhesive, in another preferred embodiment, the pressure-sensitive adhesive further comprises 5-15 parts by weight of N-tris (hydroxymethyl) methylamino-2-aminopropanesulfonic acid based on 100 parts by weight of the modified sodium alginate. The N-tri (hydroxymethyl) methylamino-2-aminopropanesulfonic acid, the modified sodium alginate and the talcum powder can form hydrogen bonds, so that the dispersibility and the compatibility of the two components can be improved, and the bonding performance of the formed pressure-sensitive adhesive is not influenced.

The fourth aspect of the present application also provides a patch comprising a pressure-sensitive adhesive tape composed of a pressure-sensitive adhesive layer and a release film layer, wherein the pressure-sensitive adhesive layer is made of the pressure-sensitive adhesive provided by the present application.

Because the pressure-sensitive adhesive provided by the application is hydrogel, the pressure-sensitive adhesive has good skin-friendly property and can reduce the risk of skin allergy; meanwhile, the pressure-sensitive adhesive tape prepared from the adhesive has good adhesive stability and proper adhesive strength, so that the normal use of the hot-compress patch can be ensured, and the pressure-sensitive adhesive tape can be easily peeled off from the skin after the hot-compress patch is used.

The patch may be of any kind including a pressure-sensitive adhesive tape, such as hot and cold application. In a preferred embodiment, the patch is a breathable medical temperature control hot compress patch, and comprises a non-woven fabric bag, a heating layer arranged inside the non-woven fabric bag, and a pressure sensitive adhesive tape for fixing the non-woven fabric bag. Preferably, the thickness of the pressure sensitive adhesive tape is 20 to 50 μm.

The present application is described in further detail below with reference to specific examples, which should not be construed as limiting the scope of the invention as claimed.

Example 1

A breathable medical temperature-control hot compress patch comprises a non-woven fabric cloth bag, a heating layer arranged in the non-woven fabric cloth bag, and a pressure-sensitive adhesive tape used for fixing the non-woven fabric cloth bag, wherein the pressure-sensitive adhesive tape consists of a pressure-sensitive adhesive with the thickness of 35 mu m and release paper.

The preparation method of the pressure-sensitive adhesive comprises the following steps:

(1) 47g of sodium alginate was dissolved in a 5% sodium hydroxide aqueous solution at 60 ℃ under heating to obtain a sodium alginate solution.

(2) 48g N- (2-chloroethyl) phthalimide was dissolved in tetrahydrofuran to give a solution of N- (2-chloroethyl) phthalimide.

(3) Dropwise adding an N- (2-chloroethyl) phthalimide solution into a sodium alginate solution, heating to 70 ℃, preserving heat, stirring, reacting for 8 hours, standing, layering, taking a water phase, concentrating and removing water to obtain modified alginic acid; infrared spectrum of modified alginic acid: 1740cm^-1(O-C＝O)，1632cm^-1(C＝O)，1330cm^-1(C-N)。

(4) Adding 15g of talcum powder (with average particle size of 200nm) into 100g of prepared modified alginic acid, and mixing at the rotating speed of 250r/min for 10min to obtain the pressure-sensitive adhesive.

Example 2

A breathable medical temperature-control hot compress patch comprises a non-woven fabric cloth bag, a heating layer arranged in the non-woven fabric cloth bag, and a pressure-sensitive adhesive tape used for fixing the non-woven fabric cloth bag, wherein the pressure-sensitive adhesive tape consists of a pressure-sensitive adhesive with the thickness of 35 mu m and release paper.

The preparation method of the pressure-sensitive adhesive comprises the following steps:

(1) 47g of sodium alginate was dissolved in a 5% sodium hydroxide aqueous solution at 60 ℃ under heating to obtain a sodium alginate solution.

(2) 52g N- (2-chloroethyl) phthalimide was dissolved in tetrahydrofuran to give a solution of N- (2-chloroethyl) phthalimide.

(3) Dropwise adding an N- (2-chloroethyl) phthalimide solution into a sodium alginate solution, heating to 70 ℃, keeping the temperature, stirring, reacting for 8 hours, standing, layering, taking a water phase, concentrating and removing water to obtain the modified alginic acid.

(4) Adding 20g of talcum powder (with average particle size of 200nm) into 100g of prepared modified alginic acid, and mixing at the rotating speed of 250r/min for 10min to obtain the pressure-sensitive adhesive.

Example 3

Based on example 1, example 3 was prepared by adding N-tris (hydroxymethyl) methylamino-2-aminopropanesulfonic acid to a pressure sensitive adhesive, a blank test was prepared by the configuration of example 1 and example 3 only with or without the addition of N-tris (hydroxymethyl) methylamino-2-aminopropanesulfonic acid, and the other preparation procedures were the same as example 1.

A breathable medical temperature-control hot compress patch comprises a non-woven fabric cloth bag, a heating layer arranged in the non-woven fabric cloth bag, and a pressure-sensitive adhesive tape used for fixing the non-woven fabric cloth bag, wherein the pressure-sensitive adhesive tape consists of a pressure-sensitive adhesive with the thickness of 35 mu m and release paper.

The preparation method of the pressure-sensitive adhesive comprises the following steps:

(1) 47g of sodium alginate was dissolved in a 5% sodium hydroxide aqueous solution at 60 ℃ under heating to obtain a sodium alginate solution.

(2) 48g N- (2-chloroethyl) phthalimide was dissolved in tetrahydrofuran to give a solution of N- (2-chloroethyl) phthalimide.

(3) Dropwise adding an N- (2-chloroethyl) phthalimide solution into a sodium alginate solution, heating to 70 ℃, keeping the temperature, stirring, reacting for 8 hours, standing, layering, taking a water phase, concentrating and removing water to obtain the modified alginic acid.

(4) Adding 15g of talcum powder (with average particle size of 200nm) and 8g N-tris (hydroxymethyl) methylamino-2-aminopropanesulfonic acid into 100g of prepared modified alginic acid, and mixing for 10min at the rotating speed of 250r/min to obtain the pressure-sensitive adhesive.

Example 4

A breathable medical temperature-control hot compress patch comprises a non-woven fabric cloth bag, a heating layer arranged in the non-woven fabric cloth bag, and a pressure-sensitive adhesive tape used for fixing the non-woven fabric cloth bag, wherein the pressure-sensitive adhesive tape consists of a pressure-sensitive adhesive with the thickness of 35 mu m and release paper.

The preparation method of the pressure-sensitive adhesive comprises the following steps:

(1) 40g of sodium alginate was dissolved in a 5% sodium hydroxide aqueous solution at 60 ℃ under heating to obtain a sodium alginate solution.

(2) 55g N- (2-chloroethyl) phthalimide was dissolved in tetrahydrofuran to give a solution of N- (2-chloroethyl) phthalimide.

(3) Dropwise adding an N- (2-chloroethyl) phthalimide solution into a sodium alginate solution, heating to 70 ℃, preserving heat, stirring, reacting for 8 hours, standing, layering, taking a water phase, concentrating and removing water to obtain modified alginic acid; infrared spectrum of modified alginic acid: 1740cm^-1(O-C＝O)，1632cm^-1(C＝O)，1330cm^-1(C-N)。

(4) Adding 15g of talcum powder (with average particle size of 200nm) into 100g of prepared modified alginic acid, and mixing at the rotating speed of 250r/min for 10min to obtain the pressure-sensitive adhesive.

Example 5

A breathable medical temperature-control hot compress patch comprises a non-woven fabric cloth bag, a heating layer arranged in the non-woven fabric cloth bag, and a pressure-sensitive adhesive tape used for fixing the non-woven fabric cloth bag, wherein the pressure-sensitive adhesive tape consists of a pressure-sensitive adhesive with the thickness of 35 mu m and release paper.

The preparation method of the pressure-sensitive adhesive comprises the following steps:

(1) 50g of sodium alginate was dissolved in a 5% sodium hydroxide aqueous solution at 60 ℃ under heating to obtain a sodium alginate solution.

(2) 45g N- (2-chloroethyl) phthalimide was dissolved in tetrahydrofuran to give a solution of N- (2-chloroethyl) phthalimide.

(3) Dropwise adding an N- (2-chloroethyl) phthalimide solution into a sodium alginate solution, heating to 70 ℃, preserving heat, stirring, reacting for 8 hours, standing, layering, taking a water phase, concentrating and removing water to obtain modified alginic acid; infrared spectrum of modified alginic acid: 1740cm^-1(O-C＝O)，1632cm^-1(C＝O)，1330cm^-1(C-N)。

(4) Adding 15g of talcum powder (with average particle size of 200nm) into 100g of prepared modified alginic acid, and mixing at the rotating speed of 250r/min for 10min to obtain the pressure-sensitive adhesive.

Example 6

A breathable medical temperature-control hot compress patch comprises a non-woven fabric cloth bag, a heating layer arranged in the non-woven fabric cloth bag, and a pressure-sensitive adhesive tape used for fixing the non-woven fabric cloth bag, wherein the pressure-sensitive adhesive tape consists of a pressure-sensitive adhesive with the thickness of 35 mu m and release paper.

The preparation method of the pressure-sensitive adhesive comprises the following steps:

(1) 30g of sodium alginate was dissolved in a 5% sodium hydroxide aqueous solution at 60 ℃ under heating to obtain a sodium alginate solution.

(2) 60g N- (2-chloroethyl) phthalimide was dissolved in tetrahydrofuran to give a solution of N- (2-chloroethyl) phthalimide.

(3) Dropwise adding an N- (2-chloroethyl) phthalimide solution into a sodium alginate solution, heating to 70 ℃, preserving heat, stirring, reacting for 8 hours, standing, layering, taking a water phase, concentrating and removing water to obtain modified alginic acid; infrared spectrum of modified alginic acid: 1740cm^-1(O-C＝O)，1632cm^-1(C＝O)，1330cm^-1(C-N)。

(4) Adding 15g of talcum powder (with average particle size of 200nm) into 100g of prepared modified alginic acid, and mixing at the rotating speed of 250r/min for 10min to obtain the pressure-sensitive adhesive.

Example 7

The differences from example 3 are: and (4) adding 15g of talcum powder (with the average particle size of 200nm) and 5g N-tris (hydroxymethyl) methylamino-2-aminopropanesulfonic acid into 100g of prepared modified alginic acid, and mixing at the rotating speed of 250r/min for 10min to obtain the pressure-sensitive adhesive.

Example 8

The differences from example 3 are: and (4) adding 15g of talcum powder (with the average particle size of 200nm) and 15g N-tris (hydroxymethyl) methylamino-2-aminopropanesulfonic acid into 100g of prepared modified alginic acid, and mixing at the rotating speed of 250r/min for 10min to obtain the pressure-sensitive adhesive.

Example 9

The differences from example 3 are: and (4) adding 15g of talcum powder (with the average particle size of 200nm) and 2g N-tris (hydroxymethyl) methylamino-2-aminopropanesulfonic acid into 100g of prepared modified alginic acid, and mixing at the rotating speed of 250r/min for 10min to obtain the pressure-sensitive adhesive.

Example 10

The differences from example 3 are: the same procedure as in example 3 was repeated except that an equivalent amount of KH550, a silane coupling agent, was used instead of N-tris (hydroxymethyl) methylamino-2-aminopropanesulfonic acid.

Comparative example 1

The differences from example 1 are: the procedure of example 1 was otherwise the same as in the case of sodium alginate without modification.

The pressure-sensitive adhesives prepared in examples 1 to 10 and comparative example 1 were subjected to performance tests, the test methods and test results were as follows: GB/T4852-2002 tests the initial viscosity, and the larger the steel ball number is, the stronger the initial viscosity is; GB/T4851-2014 tests the permanent adhesion; GB/T2792-2014 tests 180 DEG peel strength. The results of the performance tests of the pressure sensitive adhesive are shown in table 1.

TABLE 1

	Initial tack/Steel ball number	Constant viscosity force separation time/h	180 DEG peel strength/N
				Example 1	18	20.1	14.79
Example 2	17	17.2	12.36
				Example 3	18	22.4	16.58
Example 4	15	16.5	11.50
				Example 5	19	21.3	15.30
Example 6	16	15.7	16.83
				Example 7	18	20.1	13.86
Example 8	19	21.5	11.52
				Example 9	18	22.1	15.03
Example 10	16	15.0	10.42
				Comparative example 1	7	6.3	5.01

From the above description, it can be seen that the above-described embodiments of the present invention achieve the following technical effects:

comparing examples 1-2 and 4 to 6, it is found that limiting the ratio of sodium alginate to N- (2-chloroethyl) phthalimide to the preferred range in the present application facilitates the improvement of the overall performance of the pressure sensitive adhesive produced without the addition of N-tris (hydroxymethyl) methylamino-2-aminopropanesulfonic acid.

Comparing examples 1, 3 and 7 to 9, it is found that limiting the amount of N-tris (hydroxymethyl) methylamino-2-aminopropanesulfonic acid to the preferred range of the present application is advantageous in improving the overall performance of the pressure sensitive adhesive produced therefrom.

Comparing examples 3, 7 to 10, it can be seen that the addition of N-tris (hydroxymethyl) methylamino-2-aminopropanesulfonic acid is advantageous in further improving the overall performance of the pressure-sensitive adhesive prepared therefrom, as compared to the coupling agent.

Comparing examples 1 to 10 with comparative example 1, the pressure-sensitive adhesive prepared by the present application has more excellent adhesive property and adhesive stability.

It is noted that the terms first, second and the like in the description and in the claims of the present application are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the application described herein are, for example, capable of operation in sequences other than those described or illustrated herein.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.