KR20190083551A - Self healing elastomer, self healing complex and self healing film - Google Patents

Abstract

The present invention is to provide a self healing elastomer comprising a polyurethane resin including a disulfide bond in a main chain or a branch chain. The polyurethane resin of the self healing elastomer is a reactant of a polyol compound having the weight-average molecular weight of 900 to 3,500 Mw and an isocyanate compound. The self healing elastomer may repeatedly exhibit self healing and adhesive properties. Under certain temperature conditions, thermoreversible self-healing properties can be exhibited in particular.

Description

SELF HEALING ELASTOMER, SELF HEALING COMPLEX AND SELF HEALING FILM < RTI ID = 0.0 >

The present invention relates to a new self-healing elastomeric self-healing composite self-healing film. More particularly, the present invention relates to a self-healing elastomeric self-healing composite self-healing film exhibiting thermoreversible self-healing properties.

The self-healing system is an intelligent system that can extend the life span and recover the physical properties by restoring the self-structure in the molecule instead of passive repair when the structure of the material is destroyed or the physical properties are degraded due to external environmental factors.

In recent years, studies have been made to manufacture self-healing materials using a reversible chemical mechanism system that can be treated by binding in a molecular unit as compared with a capsule system which is difficult to be repeatedly treated. Although studies on individual compounds have been carried out, it has been found that even if the self-healing ability is achieved, the reaction is only performed at a high temperature, is not repeatedly restored, is slow in restoration, does not show excellent performance in terms of ductility or mechanical properties There is a problem that it is difficult to apply it to devices such as flexible devices, aerospace materials, building materials, and medical materials.

Accordingly, there is a desperate need to develop a material exhibiting excellent self-healing performance while exhibiting excellent performance in terms of ductility or mechanical properties.

KR 10-2016-0081052 A

Embodiments of the present invention provide a self-healing elastomer exhibiting thermoreversible self-healing properties.

Embodiments of the present invention provide a self-healing complex comprising the self-healing elastomer.

In still another embodiment of the present invention, there is provided a self-healing film made of the self-healing elastic material or the self-healing elastic material.

In one embodiment of the invention, the self-healing elastomer comprises a polyurethane resin having a disulfide bond in the main chain or branching chain, the polyurethane resin having an isocyanate-based compound and a weight average molecular weight of 900 to 3,500 (Mw) Wherein the self-healing elastomer is a reaction product of a polyol compound having a hydroxyl group.

In an exemplary embodiment, the polyol compound comprises a first polyol compound and a second polyol compound, the first polyol compound having a weight average molecular weight of 900 to 1500 (Mw), the second polyol compound having a weight average molecular weight And may have a weight average molecular weight of 3,500 (Mw).

In an exemplary embodiment, the polyurethane resin is obtained by reacting a polyol compound with an isocyanate compound in a molar ratio of 1: 2 to 2: 1, wherein the self-healing elastomer is a polyurethane resin and a disulfide compound in a molar ratio of 3: 1 to 2 : 1. ≪ / RTI >

In an exemplary embodiment, the disulfide bond may be comprised between 5 and 20 mole percent.

In an exemplary embodiment, the polyol compound is selected from the group consisting of polyalkylene ether glycols, polyester polyols, e-caprolactone polyols, polyethylene glycols, polypropylene glycols, polyester polyols, polycaprolactone diols, polycarbonate diols and polytetramethylene ethers Glycol, < / RTI >

In an exemplary embodiment, the isocyanate compound may include one or more selected from the group consisting of toluene diisocyanate, methylenediphenyl diisocyanate, hexamethylene diisocyanate, and isophorone diisocyanate.

In an exemplary embodiment, the disulfide compound is selected from the group consisting of 2-hydroxyl disulfide, 3,3'-dithiodipropionic acid, 2,2 '- (dithiodiethylene) Diazomethane dihydrochloride, 2,2'- (Dithodimethylene) difuran, 4-aminophenyl disulfide, 2,2'-Diaminodiethyl disulfide dihydrochloride and And 3,3'-Dihydroxydiphenyl disulfide. The term " 3,3'-dihydroxydiphenyl disulfide "

In another embodiment of the present invention, there is provided a process for producing the self-healing elastomer. Wherein the polyol compound and the isocyanate compound are mixed and then polymerized to form a polyurethane resin; And reacting the polyurethane resin with a disulfide compound to prepare a self-healing elastic body; Wherein the self-healing elastomer comprises a disulfide bond in the main chain or branching chain, and the polyol compound may have a weight average molecular weight of 900 to 3,500 (Mw).

In an exemplary embodiment, the polyol compound and the isocyanate compound may be reacted in a molar ratio of 1: 2 to 2: 1 in the preparation of the polyurethane resin.

In an exemplary embodiment, the polyurethane resin and the disulfide compound may react in a molar ratio of 3: 1 to 2: 1 in preparing the self-healing elastomer.

In another embodiment of the present invention, there is provided a self-healing film comprising the self-healing elastomer or a dry product thereof.

In yet another embodiment of the present invention, as a self-healing complex, a self-healing elastomer comprising a polyurethane resin containing a disulfide bond in the main chain or branching chain; And multi-hydrogen bondable monomers; Wherein the polyurethane resin is a reactant of a polyol compound and an isocyanate compound, and the polyol compound has a weight average molecular weight of 900 to 3,500 (Mw).

In an exemplary embodiment, the multiple hydrogen-bondable monomer is selected from the group consisting of isocyanate terminated ureido pyrimidinone (UPY-NCO) and isocyanate terminated ureido pyrimidinone (UPY-NCO) and polycarbonate diol complex ≪ / RTI >

In an exemplary embodiment, the mixing ratio of the self-healing elastomer and the multiple hydrogen-bondable monomer may be from 2: 8 to 8: 2.

In another embodiment of the present invention, there is provided a self-healing film comprising the self-healing complex or a dried product thereof.

In an exemplary embodiment, the self-healing film may exhibit a self-healing efficiency (%) of 90% or more at a temperature of 20 to 90 ° C.

In an exemplary embodiment, the self-healing film may exhibit a tensile stress in the range of 5 to 27 MPa.

The self-healing elastomer according to an embodiment of the present invention can exhibit self-recovery property and adhesion property repeatedly, and can exhibit thermo-reversible self-healing property under specific temperature conditions.

In particular, the self-healing elastomer includes a disulfide bond. Since such a disulfide bond (SS) exhibits a self-value capability of a molecular unit through chain exchange with a neighboring sulfur atom upon the damage, the disulfide bond Self-healing elastomers can exhibit excellent self-healing properties (shape recovery rate). In addition, the self-healing elastomer of the present invention includes repeating units derived from a polyol having a certain molecular weight, and can exhibit excellent self-healing efficiency not only at a high temperature but also at a low temperature. Accordingly, it can be widely used in various fields such as aerospace material, building material, medical material, coating agent and adhesive.

In addition, the self-healing elastomer can be manufactured by a very simple method, and thus is useful for commercialization.

Meanwhile, the self-healing complex prepared according to the present invention includes the self-healing elastomer and the multi-hydrogen bondable monomer, thereby inducing dual dynamic binding within the structure, thereby exhibiting improved self-healing performance.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a conceptual diagram showing a self-healing elastic body manufactured according to an embodiment of the present invention and its self-healing characteristics. FIG.
Figures 2a and 2b are conceptual diagrams illustrating self-healing complexes and their properties, prepared according to one embodiment of the present invention.
FIG. 3 is a Fourier transform infrared spectroscopy (FT-IR) spectrum of the self-healing elastic body prepared according to Examples 2 and 3 and Comparative Example 1. FIG.
4 is a graph showing differential scanning calorimetry (DSC) analysis results of self-healing elastomers prepared according to embodiments of the present invention.
FIG. 5 is a graph showing tensile stress and tensile strain of the self-healing elastic body produced according to Examples 2 and 3 and Comparative Example 1. FIG.
6 shows a cross-section of a self-healing elastomeric self-healing elastomeric film produced in accordance with embodiments of the present invention and a self-healing elastomeric film in each step.
FIGS. 7A and 7B are graphs showing changes in tensile stress according to time and temperature changes of a film made of the self-healing elastic material of Example 2. FIG.
8A and 8B are graphs showing changes in tensile stress with time and temperature change of a film made of the self-healing elastic material of Example 3. FIG.
9A and 9B are graphs showing changes in tensile stress according to time and temperature changes of a film made of the self-healing elastic material of Comparative Example 1. FIG.
Figure 10a is an NMR spectrum of ureidopyrimidinone (UPy-NCO), a quaternary hydrogen bonding compound that is end-functionalized with isocyanate, prepared according to embodiments of the present invention, Figure 10b is a non- NMR spectra of a material finally synthesized with linear UPC3K in combination with UPy-NCO using a linear polycarbonate (PC, molecular weight 3,000 g mol-1) for the synthesis of coupled dynamic-linking oligomers.
Figure 11 is a graph showing tensile stress and tensile strain changes of a self-healing film comprising self-healing elastomers and self-healing complexes prepared according to embodiments of the present invention.

Hereinafter, embodiments of the present invention will be described in detail. This is illustrated for illustrative purposes, and the technical idea of the present invention and its constitution and application are not limited thereby.

As used herein, the term " reactant " means a reaction product mainly formed as a final product formed by the reaction of materials.

Self-Healing Elastomers and Manufacturing Method Thereof

In one embodiment of the invention, a self-healing elastomer is provided comprising a polyurethane resin comprising a disulfide bond in the main chain or branching chain. Since the disulfide bond of the self-healing elastomer exhibits the self-value capability of a molecular unit through chain exchange with a neighboring sulfur atom at the time of damage, the self-healing elastomer containing the disulfide bond according to the present invention has a specific temperature 100 ° C), it can exhibit excellent self-recovery characteristics.

Meanwhile, the polyurethane resin contained in the self-healing elastomer of the present invention is produced by the reaction of an isocyanate compound and a polyol compound, wherein the polyol compound can be adjusted to have a weight average molecular weight of 900 to 3,500 (Mw). In this case, the fluidity (molecular motility) of the sample can be finally controlled by influencing the phase separation between the hard segment and the soft segment, which are components of the polyurethane, Good self-healing properties can be seen not only at the temperature but also at the low temperature.

When the polyol compound has a weight average molecular weight of less than 900 (Mw), the mobility of the polyurethane resin becomes excessively large, so that the synthesis of the polyurethane resin may be difficult. When the polyol compound has a weight average molecular weight exceeding 3,500 (Mw) Can be reduced.

In an exemplary embodiment, the polyol compound is selected from the group consisting of polyalkylene ether glycols, polyester polyols, e-caprolactone polyols, polyethylene glycols, polypropylene glycols, polyester polyols, polycaprolactone diols, polycarbonate diols and polytetramethylene ethers Glycol, < / RTI >

On the other hand, the polyol compound may be prepared to include two or more polyol compounds having molecular weights different from each other.

For example, the polyol compound may comprise a first polyol compound and a second polyol compound, wherein the first polyol compound may be produced to have a weight average molecular weight of 900 to 1500 (Mw) (Mw) to 3,500 (Mw). By using a polyol having a different molecular weight as a compound, the phase separation degree of the entire polyurethane structure can be controlled and the self-healing property can be controlled according to the controlled degree of phase separation.

Meanwhile, the isocyanate compound may include at least one member selected from the group consisting of toluene diisocyanate, methylenediphenyl diisocyanate, hexamethylene diisocyanate, and isophorone diisocyanate.

In an exemplary embodiment, the repeating unit derived from the isocyanate compound may correspond to a hard segment in the self-healing elastomer.

In an exemplary embodiment, the polyurethane resin may be a polyol compound and an isocyanate compound reacted at a molar ratio of 1: 2 to 2: 1. When the polyol compound is reacted with the isocyanate compound at a molar ratio of 1: 2 or less, the ductility is lowered, and when the polyol compound is more than 2: 1, the self-healing performance may be lowered.

On the other hand, the self-healing polymer may be a polyurethane resin and a disulfide compound reacted at a ratio of 3: 1 to 2: 1. When the reaction between the polyurethane resin and the disulfide compound is less than 3: 1, the self-healing performance is deteriorated. When the reaction rate exceeds 2: 1, the mechanical performance such as ductility and tensile strength may be deteriorated.

On the other hand, the disulfide compound may be selected from the group consisting of 2-hydroxyl disulfide, 3,3'-dithiodipropionic acid, 2,2 '- (dithiodiethylene) , 2 '- (Dithodimethylene) difuran, 4-aminophenyl disulfide, 2,2'-Diaminodiethyl disulfide dihydrochloride, and 3,3' -Dihydroxydiphenyl disulfide, and the like.

In one embodiment, the self-healing elastomer may be represented by the following formula (1).

[Chemical Formula 1]

(Wherein n is an integer of 5 to 20 and x is an integer of 10 to 40)

In an exemplary embodiment, the self-healing elastomer may have a linear or non-linear structure and may have a linear structure in particular.

On the other hand, the self-healing elastomer of the present invention may contain 5 to 20 mol% of disulfide bonds. If it is less than 5 mol%, the self-healing property may not be developed, and if it exceeds 20 mol%, the mechanical properties of the self-healing elastomer may be deteriorated.

On the other hand, the self-healing elastic body can exhibit self-healing performance even at room temperature. Specifically, it exhibits self-healing efficiency (%) of 90% or more at a temperature of 20 to 90 ° C, Efficiency can be seen.

The self-healing elastomer of the present invention exhibits the so-called " thermoreversible self-healing property " Thus, even if the self-healing elastic body is damaged, it can be cured by applying heat thereto. Thus, it is possible to perform repeated healing by controlling the heat applied to the self-healing elastic body.

In addition, the self-healing elastomer can exhibit excellent mechanical properties and exhibit tensile stresses in the range of, for example, 5 to 27 MPa.

The self-healing elastomer of the present invention can exhibit excellent self-healing properties even at a temperature of 90 ° C or less, for example, a temperature of 0 to 90 ° C at a temperature of 20 to 90 ° C, or a low temperature of 20 to 60 ° C.

Accordingly, the self-healing elastic body can be widely used in a variety of fields such as aerospace materials, building materials, medical materials, coating agents and adhesives.

In another embodiment of the present invention, there is provided a process for producing the above-mentioned self-healing elastomer. The process is very simple and useful for commercialization. The method comprises: mixing an isocyanate compound with a polyol compound having a weight average molecular weight of 900 to 3,500 (Mw) and then polymerizing to form a polyurethane resin; And reacting the polyurethane resin with a disulfide compound to prepare a self-healing elastic body; .

First, a polyol compound and an isocyanate compound are mixed and then polymerized to form a polyurethane resin.

At this time, the polyol compound and the isocyanate compound may be reacted at a molar ratio of 1: 2 to 2: 1 at the time of preparing the polyurethane resin.

Thereafter, the polyurethane resin and the disulfide compound are reacted to prepare a self-healing elastic body.

In an exemplary embodiment, the polyurethane resin and the disulfide compound may be reacted in a molar ratio of 3: 1 to 2: 1 in the preparation of self-healing elastomers.

Thus, a self-healing elastomer containing a disulfide bond in the main chain or the branch chain can be produced.

Self-healing complex and method for manufacturing the same

In another embodiment of the invention, the self-healing complex comprises a self-healing elastomer comprising a polyurethane resin comprising a disulfide bond in the main chain or branching chain; And multi-hydrogen bondable monomers; A self-healing complex is provided. The self-healing elastomer in the self-healing complex comprises substantially the same or similar construction as the self-healing elastomer described above.

That is, the self-healing elastomer of the self-healing complex includes a polyurethane resin containing a disulfide bond, wherein the polyurethane resin of the self-healing elastomer is a polyol compound having a weight average molecular weight of 900 to 3,500 (Mw) and an isocyanate compound Lt; / RTI >

On the other hand, the self-healing elastomer may further include a multi-hydrogen bondable monomer. In this case, the self-healing complex may include a self-healing elastomer including a covalent bond and a multi-hydrogen bondable monomer including a hydrogen bond (See Figs. 2A and 2B). In such a case, the self-healing performance can be further increased.

In an exemplary embodiment, the multiple hydrogen-bondable monomer is selected from the group consisting of isocyanate terminated ureido pyrimidinone (UPY-NCO), isocyanate terminated ureido pyrimidinone (UPY-NCO) and polycarbonate diol complex And the like.

In one embodiment, the multiple hydrogen-bondable monomers may have a weight average molecular weight of 400 to 700 g / mol.

In an exemplary embodiment, the mixing ratio of the self-healing elastomer and the self-healing complex in the self-healing complex may be from 2: 8 to 8: 2. If it is out of the above range, the self-healing efficiency may be lowered or it may be difficult to form it as a composite.

The self-healing complex of the present invention includes a self-healing elastomer containing a covalent bond and a multiple hydrogen-bondable monomer containing a hydrogen bond. In the self-healing complex, covalent derivatives and non-covalent derivatives are mixed, and the effect of shape recovery at the time of damage can be maximized.

In another embodiment of the present invention, there is provided a process for producing a self-healing complex as described above. The self-healing complex may comprise mixing self-healing elastomers and multiple hydrogen-bondable monomers.

The self-healing elastomers and multiple hydrogen-bondable monomers in the self-healing complex of the present invention all have self-healing properties, and the factors expressing self-healing in the above materials are classified into non-covalent or covalent bonds, Are mixed with each other to produce a composite material, complementary characteristics can be derived.

In addition, when the self-healing complex is used, the temperature and speed of expression of the self-healing performance can be improved as compared with the case of using the self-healing elastic body. Accordingly, it can be widely used in various fields such as aerospace material, building material, medical material, coating agent and adhesive.

Self-healing film

In another embodiment of the present invention, a self-healing film comprising the self-healing elastomer or self-healing complex can be produced. Alternatively, the self-healing film may comprise a dried product of the self-healing elastomer or a dried product of the self-healing complex.

Specifically, the self-healing elastomeric or self-healing complex can be dried for 10 to 30 hours to form a self-healing film. Since the self-healing film includes the above-mentioned self-healing elastic body (or self-healing complex), the self-healing film can exhibit excellent self-healing efficiency and excellent mechanical performance.

In an exemplary embodiment, the self-healing film may exhibit a self-healing efficiency of 90% or more at a temperature of 20 to 90 占 폚.

In an exemplary embodiment, the self-healing film may exhibit a tensile stress in the range of 5 to 27 MPa.

As described above, the self-healing elastic body of the present invention can exhibit self-recovery property and adhesive property repeatedly, and can exhibit thermo-reversible self-healing property under specific temperature conditions. In particular, the self-healing elastomer includes a disulfide bond. Since such a disulfide bond shows a self-value capability of a molecular unit through chain exchange with a neighboring sulfur atom at the time of damage, the self- The healing elastomer can exhibit excellent self-recovery properties (shape recovery rate).

In addition, the self-healing elastomer of the present invention includes a repeating unit derived from a polyol compound having a certain range of molecular weight. In this case, the self-healing elastomer can exhibit excellent self-recovery properties at a low temperature as well as a high temperature.

In addition, it is possible to produce self-healing films by drying them. Such self-healing films can exhibit excellent self-healing efficiency, ductility and mechanical performance. Accordingly, it can be widely used in various fields such as aerospace material, building material, medical material, coating agent and adhesive.

Hereinafter, the present invention will be described in more detail with reference to Examples. It is to be understood by those skilled in the art that these embodiments are only for illustrating the present invention and that the scope of the present invention is not construed as being limited by these embodiments.

[Experimental Example]

Self-healing elastomer

[Examples 1 to 3]

Solution synthesis was carried out using chloroform as a solvent. First, a polycarbonate diol (PC-diol) and 4,4'-diphenylmethane diisocyanate (MDI) (Sigma Aldrich) were reacted at 70 ° C for 3 hours in a 500 mL beaker type flask to prepare a polymer. (UH-100 or UH-300 manufactured by UBE Industries, Ltd. ETERNACOLL® UH) PC-diol 1: 1,000 g / mol, a PC-diol having a molecular weight of 1,000 g / diol 2: 3,000 g / mol). Then, 2-hydroxyethyl disulfide (2HEDS) (Sigma Aldrich) was reacted with the polymer to prepare a self-healing elastomer. At this time, the compositions according to Examples 1 to 3 were prepared by varying the feeding ratios of PC-diol 1, PC-diol 2, MDI and 2HEDS as shown in Table 1 below. Thereafter, the composition was precipitated in methanol, completely dried in a vacuum oven for 24 hours, and then re-dissolved in DMF solvent to prepare a sample according to Examples 1 to 3 which had a film thickness of about 400 to 450 mm.

[Comparative Example 1]

The same procedure was followed as in Example 1 except that 1,4-butanediol (1,4 BD-diol), a side chain extender, was used instead of 2-hydroxyethyl disulfide (2HEDS) A healing elastomer was prepared

The molar ratios in Examples 1 to 3 and Comparative Example 1 are shown in Table 1 below.

Remarks PC-diol < / RTI > 1 (mmol) PC-diol 2 (mmol) MDI (mmol) 2HEDS (mmol) 1.4 BD-diol (mmol) Example 1 40 - 20 20 - Example 2 - 6.67 13.4 6.67 - Example 3 10 3.3 26.6 13.3 - Comparative Example 1 10 3.3 26.6 - 13.3

(In Table 1, the molar ratio of PC-diol: MDI: 2HEDS in Examples 1 and 2 is 2: 1: 1, and the molar ratio of PC-diol: MDI: 2HEDS in Example 2 is 1 : The molar ratio of PC-diol: MDI: 1,4 BD-diol of Comparative Example 1 was 1: 2: 1, the molar ratio of PC-diol: MDI: 2HEDS of Example 2 was 1: 2: 1. In Table 1, the molar ratio of the hard segment MDI and the soft segment PC-diol to the 2HEDS (or 1, 4 BD-diol) molar ratio is 1: 1.

 [Experimental Example 1: Synthesis analysis of elastomer]

Experiments were carried out using FT-IR and Raman spectroscopy to confirm the chemical structures of the samples prepared according to Examples 2 and 3 and Comparative Example 1, which are shown in FIG.

Referring to FIG. 3, the samples according to Examples 2 and 3 are composed of repeating units derived from MD of a hard segment, repeating units derived from 2-hydroxyethyl disulfide, and repeating units derived from soft-segment poly Carbonate diol. As a result, it was confirmed that the elastomer synthesized in two segments having very different physical and chemical thermodynamic properties has a phase separation structure due to thermophilic incompatibility. In addition, the characteristic peaks of the NCO group at 2270 cm -1 disappear and at the same time, -NH stretching vibration (3500-3200 cm -1), δNH stretching vibration (1539-1531 cm -1), -C═O stretching vibration (1760- It was confirmed that a linear polyurethane block copolymer elastomer was synthesized by confirming formation of bands of 1690 cm -1, CO stretching vibration (1245 cm -1) and COC stretching vibration (1162-1159 and 1046-1044 cm -1) . In other words, it was confirmed that polyurethane was successfully synthesized by putting a chain extender (2HED and BD). However, it was confirmed that the sample according to Comparative Example 1 did not contain a repeating unit derived from 2-hydroxyethyl disulfide.

[Experimental Example 2: DSC analysis]

The T _g of samples prepared according to Examples 2 and 3 and Comparative Example 1 The values were confirmed by DSC analysis (Fig. 4). It can be confirmed that the self-healing elastomers produced according to the changes in the content of PC-diol having different molecular weights show different physical properties. Specifically, the elastomer synthesized in Example 2 (Mw 3,000 g / mol) had a T _g value of -25.4 ° C, but Example 3, which contained PC-diol at 1,000 g / mol and 3,000 g / mol, It was confirmed that Tg was increased. In addition, since Comparative Example 1 was also prepared to contain 1,4-butanediol instead of 2HEDS, the T _g tended to increase relatively.

[Experimental Example 3: Mechanical Properties Analysis]

The intrinsic mechanical properties (tensile stress and tensile strain) of the samples prepared according to Examples 2 and 3 and Comparative Example 1 are shown in Fig. The values shown in Fig. 5 are shown in Table 2 below.

Sample name Tensile strain (%) Tensile Stress (MPa) Tensile modulus (MPa) Comparative Example 1 306.61 + - 8.61 6.89 + - 0.48 47.13 + - 0.97 Example 2 536.61 + - 47.13 24.87 ± 2.16  116.08 ± 2.65 Example 3 633.27 ± 24.04 6.63 + 0.355 4.09 ± 0.56

As a result, it was confirmed that tensile stress and tensile modulus were increased with use of a polyol having a high molecular weight. In addition, the self-healing elastomers containing disulfide bonds showed a tendency to increase tensile stress while decreasing tensile strain.

 [Experimental Example 4: Characteristic Analysis of Self-Recovery]

The samples according to Examples 2 and 3 and Comparative Example 1 were subjected to a physical notch having a depth of about 150 mm with a sharp knife, and then the two cut surfaces were brought into contact with each other again. Then, at 50, 70 and 90 ° C The surface was photographed after heat treatment for 5 minutes, 1 hour, and 6 hours, respectively, and is shown in FIG. 6 (only the sample according to Example 3 is shown in cross section.

In addition, the self-healing efficiency of the sample according to Examples 2 and 3 and Comparative Example 1 under the respective temperature and time conditions was measured. The self-healing efficiency was calculated by the following formula (1) The results were confirmed in Figs. 7A to 9B. FIGS. 7A and 7B are graphs showing changes in tensile stress and tensile strain according to time and temperature changes of a film made of the self-healing elastic material of Example 2. FIG. FIGS. 8A and 8B are graphs showing changes in tensile stress and tensile strain according to time and temperature changes of a film made of the self-healing elastic material of Example 3. FIG. FIGS. 9A and 9B are graphs showing changes in tensile stress and tensile strain according to time and temperature changes of a film made of the self-healing elastic material of Comparative Example 1. FIG.

[Equation 1]

Self-healing efficiency (%) = [(tensile strain or tensile stress of self-restored elastomer) / (tensile strain or tensile stress of original elastomer)] X100

As a result, in Example 2 and Comparative Example 1, a tensile strain of 10% or less and a tensile stress of 30% or less, respectively, at 50 ° C; A tensile strain of less than 10% and a tensile stress of less than 20% at 70 ° C respectively; And a tensile stress of 50% or less and a tensile stress of 20 to 50% at 90 ° C, respectively, and it was confirmed that the self-recovery efficiency was 50% or more only at a temperature higher than 90 ° C.

On the other hand, Example 3 exhibits a tensile strain of 20-80% and a tensile stress of 20-80% at 50 ° C, respectively, and a tensile strain of 40-80% and a tensile strain of 40-70% at 70 ° C, respectively , And tensile strain of 50-99% and tensile stress of 30-80% at 90 ° C, respectively, and it was confirmed that the self-restoration efficiency was 70% or more and the self-restoration efficiency was 90% or more even at a high temperature as well as a low temperature.

As a result, it was confirmed that the sample according to Example 3 had the best self-healing properties.

Self-healing complex

[Example 4]

Amino-4-hydroxy-6-methylpyrimidine (hereinafter referred to as " 2-amino-4-hydroxypyrimidine ") was synthesized to synthesize ureidopyrimidinone hydroxy-6-methylpyrimidine and 1,6-diisocyanato-hexane were charged together with pyridine catalyst, and the mixture was heated to 100 ° C under a nitrogen gas atmosphere and stirred for 16 hours. Then, the reaction product was purified by using heptane and acetone, filtered, and then vacuum-dried at 60 DEG C for 24 hours to obtain UPy-NCO. In FIG. 10A, the synthesis of UPy-NCO was evaluated using ¹ H NMR (solvent CDCl ₃ ).

Then, a linear polycarbonate diol (PC, molecular weight: 3,000 g / mol) was dissolved in a chloroform solvent to introduce the prepared quaternary hydrogen-bonding compound (UPy-NCO) UPy-NCO was added at an equivalent ratio. Thereafter, the catalyst was added, and the mixture was stirred at 60 ° C for 16 hours. The formed urea was filtered, and silica gel was added to remove unreacted UPy-NCO. Subsequently, the silica gel was filtered, and the filtrate was concentrated and added to hexane to precipitate a multi-hydrogen-bondable monomer (organic oligomer functionalized with a tetra-heavy hydrogen bond). The precipitate was filtered and dried at room temperature for 24 hours, (UPy-NCO-PC) was obtained. In FIG. 10B, the synthesis was evaluated using 1 H NMR (solvent CDCl ₃ ).

Referring to FIG. 10B, the position, cleavage characteristics and atomic ratio of each peak were examined by 1H NMR spectrum. As a result, the synthesis of UPy-NCO-linearized linear hydrogen-bonding monomer (UPy-NCO-PC) .

Specifically, it was confirmed that the urethane functional groups (peaks 5 and 9) were newly formed by the hydroxyl group bonding of the isocyanate functional group and the PC terminal of UPy. Particularly, when the integral ratio of peak 4 and peak d was analyzed, To 96% of the total. In addition, it was confirmed that UPy-NCO imparts the quaternary hydrogen bonding force to PC from the amine peaks generated at 10 ppm or more.

Then, the self-healing elastomer prepared according to Example 3 and the prepared multi-hydrogen bondable monomer were blended and polymerized to obtain a polyurethane copolymer having a multiple dynamic bonding structure in which non-covalent bonding and covalent bonding were mixed Self-healing complex). The self-healing elastomer prepared according to Example 3 and the prepared multiple hydrogen-bondable monomer were dissolved in a chloroform solvent at room temperature for 6 hours using a magnetic bar, and then the thickness of about 300 mm (± 5-8%) was measured Was prepared.

At this time, the multi-hydrogen bondable monomer functions as a compound exhibiting non-covalent bond-type dynamic bonding, and the self-healing elastomer functions as a compound in which the arrangement of soft segment segments is controlled by covalent bond type dynamic bonding.

[Experimental Example 5: Mechanical Properties Analysis]

The stress-strain of the films comprising the self-healing elastomer according to Example 3, the multiple hydrogen-bondable monomer and the self-healing complex according to Example 4 was examined and shown in FIG.

11, when the self-healing composite according to Example 4 was used, the elongation was decreased, but the elastic modulus and the breaking strength were both increased.

The embodiments of the present invention described above should not be construed as limiting the technical idea of the present invention. The scope of protection of the present invention is limited only by the matters described in the claims, and those skilled in the art will be able to modify the technical idea of the present invention in various forms. Accordingly, such improvements and modifications will fall within the scope of protection of the present invention as long as it is obvious to those skilled in the art.

Claims (17)

As self-healing elastomers,
A polyurethane resin containing a disulfide bond in the main chain or the branch chain,
Wherein the polyurethane resin is a reaction product of an isocyanate compound and a polyol compound having a weight average molecular weight of 900 to 3,500 (Mw). The method according to claim 1,
Wherein the polyol compound comprises a first polyol compound and a second polyol compound,
Wherein the first polyol compound has a weight average molecular weight of 900 to 1500 (Mw)
Wherein the second polyol compound has a weight average molecular weight of 2,500 to 3,500 (Mw). The method according to claim 1,
The polyurethane resin is obtained by reacting a polyol compound and an isocyanate compound at a molar ratio of 1: 2 to 2: 1,
Wherein the self-healing elastomer is a polyurethane resin and a disulfide compound reacted at a ratio of 3: 1 to 2: 1. The method according to claim 1,
Wherein the disulfide bond is comprised between 5 and 20 mole%. The method according to claim 1,
Wherein the polyol compound is selected from the group consisting of polyalkylene ether glycols, polyester polyols, e-caprolactone polyols, polyethylene glycols, polypropylene glycols, polyester polyols, polycaprolactone diols, polycarbonate diols and polytetramethylene ether glycols Self-healing elastomer comprising at least one. The method according to claim 1,
Wherein the isocyanate compound comprises at least one member selected from the group consisting of toluene diisocyanate, methylenediphenyl diisocyanate, hexamethylene diisocyanate, and isophorone diisocyanate. The method according to claim 1,
The disulfide compound may be selected from the group consisting of 2-hydroxyl disulfide, 3,3'-dithiodipropionic acid, 2,2 '- (dithiodiethylene) '- (Dithodimethylene) difuran, 4-aminophenyl disulfide, 2,2'-Diaminodiethyl disulfide dihydrochloride and 3,3'-di Wherein the self-healing elastomer comprises at least one selected from the group consisting of 3,3'-Dihydroxydiphenyl disulfide. A self-healing elastic body,
Mixing a polyol compound and an isocyanate compound and then polymerizing to form a polyurethane resin; And
Preparing a self-healing elastomer by reacting the polyurethane resin with a disulfide compound; Lt; / RTI >
The self-healing elastomer comprises a disulfide bond in the main chain or the branch chain,
Wherein said polyol compound has a weight average molecular weight of 900 to 3,500 (Mw). 9. The method of claim 8,
Wherein the polyol compound and the isocyanate compound are reacted at a molar ratio of 1: 2 to 2: 1 in the production of the polyurethane resin. 9. The method of claim 8,
Wherein the polyurethane resin and the disulfide compound react in a molar ratio of 3: 1 to 2: 1 at the time of preparing the self-healing elastomer. A self-healing film comprising a self-healing elastomer according to any one of claims 1 to 7 or a dry product thereof. As self-healing complexes,
A self-healing elastomer comprising a polyurethane resin containing a disulfide bond in the main chain or branching chain; And multi-hydrogen bondable monomers; Lt; / RTI >
Wherein the polyurethane resin is a reactant of a polyol compound and an isocyanate compound, and the polyol compound has a weight average molecular weight of 900 to 3,500 (Mw). 13. The method of claim 12,
The multi-hydrogen bondable monomer is selected from the group consisting of isocyanate terminated functionalized ureido pyrimidinone (UPY-NCO) and isocyanate terminated functional ureido pyrimidinone (UPY-NCO) and polycarbonate diol Self-healing complex greater than 1. 13. The method of claim 12,
Wherein the mixing ratio of the self-healing elastomer to the multi-hydrogen bondable monomer is from 2: 8 to 8: 2. A self-healing film comprising a self-healing complex according to any one of claims 12 to 14 or a dried product thereof. 16. The method of claim 15,
The self-healing film has a self-healing efficiency (%) of 90% or more at a temperature of 20 to 90 ° C. 16. The method of claim 15,
Wherein the self-healing film exhibits a tensile stress in the range of 5 to 27 MPa.

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