Shape memory polymer and preparation method and application thereof
阅读说明：本技术 一种形状记忆聚合物及其制备方法和应用 (Shape memory polymer and preparation method and application thereof ) 是由 陈少军 肖旋 陈恒 卓海涛 于 2019-08-15 设计创作，主要内容包括：本发明提供了形状记忆聚合物,由单体A、二异氰酸酯和分子量为400～1000的二元醇共聚,然后将所的聚合物与单体B季铵盐化得到；在其中单体A与二异氰酸酯、二元醇和单体B的摩尔比例为1：[0.9-1.1]:[0-1]：[0.1-1.1]；所述单体A为带两个羟基的甜菜碱。与现有技术相比,本发明所述的形状记忆聚合物采用甜菜碱作为单体,显著提升了本发明的形状记忆聚合物的生物相容性和抗菌性能。另外通过合理的配方调配使其具备良好的形状记忆性能。最后所述的形状记忆聚合物还具备自修复性能,在一定湿度下可以自我修复,自我修复条件很温和。(The invention provides a shape memory polymer, which is prepared by copolymerizing a monomer A, diisocyanate and dihydric alcohol with the molecular weight of 400-1000, and then salifying the polymer and a monomer B quaternary ammonium; wherein the molar ratio of monomer a to diisocyanate, diol and monomer B is 1: [0.9-1.1]:[0-1]: [0.1-1.1 ]; the monomer A is betaine with two hydroxyl groups. Compared with the prior art, the shape memory polymer provided by the invention adopts betaine as a monomer, so that the biocompatibility and antibacterial property of the shape memory polymer are obviously improved. In addition, the material has good shape memory performance through reasonable formula blending. Finally, the shape memory polymer also has self-repairing performance, can be self-repaired under certain humidity, and has mild self-repairing condition.)
1. A shape memory polymer characterized by: copolymerizing a monomer A, diisocyanate and dihydric alcohol with the molecular weight of 400-1000, and then salinizing the polymer and monomer B to obtain quaternary ammonium salt; wherein the molar ratio of monomer a to diisocyanate, diol and monomer B is 1: [0.9-1.1]:[0-1]: [0.1-1.1 ]; the chemical formula of the monomer A is
Any one of them;
wherein R has the formula-CnH2nR' has the formula-CxH2x，x＝0～18。
2. A shape memory polymer in accordance with claim 1, wherein: the diisocyanate comprises at least one of hexamethylene diisocyanate, diphenylmethane diisocyanate and isophorone diisocyanate.
3. A shape memory polymer in accordance with claim 1, wherein: the dihydric alcohol comprises at least one of 1, 4-butanediol, propylene glycol, ethylene glycol, and 1, 6-hexanediol.
4. A shape memory polymer in accordance with claim 1, wherein: the monomer B is chlorinated or brominated aliphatic carboxylic acid or aliphatic carboxylate, and the length of the aliphatic chain segment is 2-18.
5. A shape memory polymer in accordance with claim 4, wherein: the carboxylic acid or carboxylate salt includes at least one of bromoacetic acid, chloroacetic acid, bromobutyric acid, chlorobutyric acid, bromohexanoic acid, and chlorohexanoic acid, and salts thereof.
6. A method of preparing a shape memory polymer according to any of claims 1 to 5, comprising the steps of:
s01: preparing a monomer A and diisocyanate in proportion under an inert environment, adding an organic solvent, adding a catalyst, and heating for reaction;
s02: adding dihydric alcohol in proportion under an inert environment, and heating to react to obtain a shape memory polymer precursor solution;
s03: and adding the solution of the monomer B into the shape memory polymer precursor solution in proportion under an inert environment, and reacting to obtain the shape memory polymer solution.
7. The method of preparing a shape memory polymer of claim 6, wherein: the catalyst comprises at least one of dibutyltin dilaurate, stannous octoate and tetramethylethylenediamine.
8. The method of preparing a shape memory polymer of claim 6, wherein: the heating reaction condition in the step S01 is that the reaction is carried out for 1-4h at the temperature of 60-80 ℃;
the heating reaction condition in the step S02 is that the reaction is carried out for 1-5h at the temperature of 60-80 ℃;
the heating reaction condition in the step S03 is that the reaction is carried out for 6-24h at 40-80 ℃.
9. The method of preparing a shape memory polymer of claim 6, wherein: the mass fraction of the solute in the step S02 is 20-40%;
the mass fraction of the solute in the step S03 is 5-15%.
10. Use of a shape memory polymer according to any of claims 1 to 5 in the fields of biomedical, smart apparel and wearable devices.
Technical Field
The invention belongs to the field of high molecular materials, and particularly relates to a shape memory polymer, and a preparation method and application thereof.
Background
Shape memory polymers are intelligent polymers that deform when an external stimulus (e.g., temperature, electromagnetic, solvent, light) is sensed, fix a temporary shape after the stimulus is removed, and recover to the original shape when exposed to an environmental stimulus again. Shape memory materials can be classified into a thermotropic type, a photoinduced type, a chemical induction type, an electromagnetic induction type, and the like according to different stimulation conditions. To date, shape memory polymer materials are widely used in high-end fields such as biomedical, textile clothing, aerospace and the like, and various shape memory polymers have been developed and used; but its application in the biomedical field requires good biocompatibility and moisture sensitivity characteristics, which are not possessed by the conventional thermotropic shape memory polymers. Therefore, the method has very important application prospect in improving the biocompatibility of the common thermotropic shape memory polymer.
In the fields of biomedical treatment, textile clothing and wearable equipment, intelligent materials with good performance are urgently needed. However, since these devices are directly contacted with the human body, and some devices are even implanted into the body, it is necessary to have good biocompatibility, and in addition, the devices are exogenous foreign matters, have good compatibility, and are easy to cause infection, so that it is necessary to have antibacterial performance. The existing shape memory polymers have no antibacterial property. The existing polymer with antibacterial performance cannot give consideration to good shape memory function.
In order to meet the recent requirements for smart materials, it is necessary to develop a shape memory polymer smart material having good biocompatibility and good antibacterial properties.
Disclosure of Invention
The invention aims to provide a shape memory polymer, which aims to solve the technical problem that the existing shape memory polymer cannot give consideration to both antibacterial performance and biocompatibility.
In order to solve the technical problems, the invention provides a shape memory polymer on one hand, which is obtained by copolymerizing a monomer A, diisocyanate and dihydric alcohol with the molecular weight of 400-1000 and then carrying out quaternary ammonium salinization on the obtained polymer and a monomer B; wherein the molar ratio of monomer a to diisocyanate, diol and monomer B is 1: [0.9-1.1]:[0-1]: [0.1-1.1 ]; the chemical formula of the monomer A is
Any one of them;
wherein R has the formula-CnH2nR' has the formula-CxH2x，x＝0～18。
Preferably, the diisocyanate comprises at least one of hexamethylene diisocyanate, diphenylmethane diisocyanate, isophorone diisocyanate.
Preferably, the dihydric alcohol comprises at least one of 1, 4-butanediol, monopropylene glycol, monoethylene glycol and 1, 6-hexanediol.
Preferably, the monomer B is chlorinated or brominated aliphatic carboxylic acid or aliphatic carboxylate, and the length of an aliphatic chain segment of the monomer B is 2-18.
Further preferably, the carboxylic acid or carboxylate salt includes at least one of bromoacetic acid, chloroacetic acid, bromobutyric acid, chlorobutyric acid, bromohexanoic acid, and chlorohexanoic acid, and salts thereof.
In another aspect, the present invention provides a method for preparing the shape memory polymer, which comprises the following steps:
s01: preparing a monomer A and diisocyanate in proportion under an inert environment, adding an organic solvent, adding a catalyst, and heating for reaction;
s02: adding dihydric alcohol in proportion under an inert environment, and heating to react to obtain a shape memory polymer precursor solution;
s03: and adding the solution of the monomer B into the shape memory polymer precursor solution in proportion under an inert environment, and reacting to obtain the shape memory polymer solution.
Preferably, the catalyst comprises at least one of dibutyltin dilaurate, stannous octoate, and tetramethylethylenediamine.
Preferably, the heating reaction in the step S01 is carried out at 60-80 ℃ for 1-4 h;
the heating reaction condition in the step S02 is that the reaction is carried out for 1-5h at the temperature of 60-80 ℃;
the heating reaction condition in the step S03 is that the reaction is carried out for 6-24h at 40-80 ℃.
Preferably, the mass fraction of the solute in the step S02 is 20-40%;
the mass fraction of the solute in the step S03 is 5-15%.
The invention also provides application of the shape memory polymer in the fields of biomedicine, intelligent clothing and wearable equipment.
Compared with the prior art, the shape memory polymer provided by the invention adopts betaine as a monomer, so that the biocompatibility and antibacterial property of the shape memory polymer are obviously improved. In addition, the material has good shape memory performance through reasonable formula blending. Finally, the shape memory polymer also has self-repairing performance, can be self-repaired under certain humidity, and has mild self-repairing condition.
The preparation method of the shape memory polymer does not have any high-threshold operating condition, does not use a reagent with strong pollution, has good controllability of each step, adopts mature known reactions and has high yield. Therefore, the method is suitable for large-scale popularization and application.
Drawings
FIG. 1 is a schematic diagram of the molecular structure of a shape memory polymer according to an embodiment of the present invention;
FIG. 2 is a shape memory curve of a shape memory polymer according to an embodiment of the present invention;
FIG. 3 is an infrared test chart of a shape memory polymer according to an embodiment of the present invention;
FIG. 4 is a nuclear magnetic hydrogen spectrum of a shape memory polymer according to an embodiment of the present invention;
FIG. 5 is a self-healing performance test chart of a shape memory polymer according to an embodiment of the present invention;
FIG. 6 is a diagram illustrating the re-molding performance of a shape memory polymer according to an embodiment of the present invention.
Detailed Description
In order to make the technical problems, technical solutions and advantageous effects to be solved by the present invention more clearly apparent, the present invention is further described in detail below with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
The embodiment of the invention provides a shape memory polymer, which is obtained by copolymerizing a monomer A, diisocyanate and dihydric alcohol with the molecular weight of 400-1000 and then performing quaternary ammonium salinization on the obtained polymer and a monomer B; wherein the molar ratio of monomer a to diisocyanate, diol and monomer B is 1: [0.9-1.1]:[0-1]: [0.1-1.1 ]; the chemical formula of the monomer A is
Any one of them;
wherein R has the formula-CnH2n，R’Is of the general formula-CxH2x，x＝0～18。
Specifically, in a preferred embodiment, the diisocyanate comprises at least one of hexamethylene diisocyanate, diphenylmethane diisocyanate, and isophorone diisocyanate. The diisocyanate has good stability and strong reaction activity. And the raw materials are easy to obtain, so that the method is the first choice for the polyurethane reaction.
Specifically, in a preferred embodiment, the diol comprises at least one of 1, 4-butanediol, monopropylene glycol, monoethylene glycol and 1, 6-hexanediol. The small molecular alcohols are selected to have low melting point and good compatibility on one hand, and short carbon chains and high reaction activity on the other hand, provide crystallization cores, promote the high molecular weight polyester alcohol phase in polyurethane to quickly form a crystallization phase, and promote the shape memory polymer to quickly fix a temporary shape.
Specifically, in a preferred embodiment, the monomer B is chlorinated or brominated aliphatic carboxylic acid or aliphatic carboxylate, and the length of an aliphatic chain segment of the monomer B is 2-18. In a further preferred embodiment, the carboxylic acid or carboxylate salt comprises at least one of bromoacetic acid, chloroacetic acid, bromobutyric acid, chlorobutyric acid, bromohexanoic acid and chlorohexanoic acid, and salts thereof. The short carbon chain can be selected from chloro compounds, so that the price is advantageous, but when the carbon chain is longer, bromo compounds are generally selected when the activity is lower, so that the activity is higher. The residual betaine in the system is sufficiently basic to act as both a catalyst and a reactant, and preferably a carboxylate is selected to provide a further basic environment to promote quaternization. Finally, the carboxyl can also improve the water solubility of the shape memory polymer and further improve the biocompatibility and antibacterial property of the shape memory polymer.
In conclusion, betaine is used as a monomer, so that the shape memory polymer material has antibacterial performance, and the polymer system has good biological affinity due to the existence of a large number of groups such as carbonyl, amido bond, amino, ether bond and the like; however, since betaine has a rigid aromatic ring structure and is not easy to have a good shape memory function, the shape memory function is enhanced by the ratio of monomers. In addition, on one hand, the hydrophilicity is good due to a large number of hydrophilic groups such as carbonyl groups, amido bonds, amino groups, ether bonds and the like in a polymer system; on the other hand quaternization and addition of carboxylic acids further enhance their water solubility. Under the environment with higher humidity, the hydrophilic property is added, so that the shape memory polymer can automatically enrich water, the intermolecular distance of the cross section is shortened after the shape memory polymer is dissolved, and the self-repairing effect is achieved under the action of the active group. Finally, the shape memory polymer has rich and adjustable performance by means of chain length of a group, monomer ratio, reaction condition control and the like, and meets different application scenes.
In another aspect, the present invention provides a method for preparing the shape memory polymer, which comprises the following steps:
s01: preparing a monomer A and diisocyanate in proportion under an inert environment, adding an organic solvent, adding a catalyst, and heating for reaction;
s02: adding dihydric alcohol in proportion under an inert environment, and heating to react to obtain a shape memory polymer precursor solution;
s03: and adding the solution of the monomer B into the shape memory polymer precursor solution in proportion under an inert environment, and reacting to obtain the shape memory polymer solution.
In a specific step S01, the catalyst includes at least one of dibutyltin dilaurate, stannous octoate, and tetramethylethylenediamine. The tin catalyst is a common polyurethane catalyst, and has easily obtained raw materials and good catalytic effect. The crosslinking reaction is promoted by the addition of a small amount of tetramethylethylenediamine.
Specifically, the heating reaction in the step S01 is carried out for 1-4h at 60-80 ℃;
specifically, the heating reaction in the step S02 is carried out for 1-5h at 60-80 ℃;
specifically, the heating reaction condition in the step S03 is to react for 6 to 24 hours at 40 to 80 ℃.
Specifically, the mass fraction of the solute in the step S02 is 20-40%;
specifically, the mass fraction of the solute in the step S03 is 5 to 15%.
The concentration and the temperature are controlled to control the polymerization reaction rate, ensure the controllability of the polymerization reaction, prevent uncontrollable conditions such as excessive polymerization and the like, and obtain stable and uniform products.
The invention also provides application of the shape memory polymer in the fields of biomedicine, intelligent clothing and wearable equipment. The shape memory polymer provided by the embodiment of the invention has good antibacterial performance, biological affinity and self-repairing performance, so that the shape memory polymer can be applied to the field of biological materials, such as the fields of biological medicine, intelligent clothing and wearable equipment.
The following is a further description of the shape memory polymer embodiments of the present invention with reference to the accompanying examples and drawings.