KR20170067332A

KR20170067332A - Graphene oxide/polyurethante composite, preparation method thereof and medical tube comprising the same

Info

Publication number: KR20170067332A
Application number: KR1020150173875A
Authority: KR
Inventors: 허훈; 최석훈; 이지현
Original assignee: 한국생산기술연구원
Priority date: 2015-12-08
Filing date: 2015-12-08
Publication date: 2017-06-16
Also published as: KR101754994B1

Abstract

The present invention relates to a graphene oxide / polyurethane composite, a method for producing the graphene oxide / polyurethane composite, and a medical tube comprising the graphene oxide / polyurethane composite, and more particularly to a graphene oxide / polyurethane composite in which graphene oxide and polyurethane are chemically bonded, And a medical tube containing the same.
According to the present invention, application of a graphene oxide / polyurethane composite excellent in compatibility with polyurethane to an outer layer of a medical tube can be expected to improve the mechanical strength and improve the pressure resistance.

Description

TECHNICAL FIELD The present invention relates to a graphene oxide / polyurethane composite, a method for producing the graphene oxide / polyurethane composite, and a medical tube containing the same. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a graphene oxide /

The present invention relates to a graphene oxide / polyurethane composite polymerized by in-situ method using functional groups present in graphene oxide, a method for producing the graphene oxide / polyurethane composite, and a medical tube having improved pressure resistance using the graphene oxide / polyurethane composite.

As the development of modern industry and the demand of high functional products are increasing, the market of polymer complexes in which various materials and polymers are combined is being developed, despite being expensive materials.

Among various materials that can be combined with polymers, graphene, which is widely regarded as a carbon material, is considered as a material capable of satisfying both high rigidity and light weight due to high rigidity and low density. Various graphene / polymer complexes have been proposed.

Polymers used in graphene / polymer composites include epoxy, polyaniline, polycarbonate, and polycaprolactone. Methods for producing graphene / polymer are divided into in-situ polymerization, solution mixing, and direct mixing. The in-situ polymerization method is a method for uniformly dispersing in a polymer resin by adding graphene or functionalized graphene to a state where a monomer and a monomer are synthesized at an intermediate stage of polymer synthesis It is one. The graphene / polymer composite produced by the in-situ polymerization method is a composite material prepared by inducing grafting of graphene oxide and a polymer because the monomer is inserted between the expanded graphene oxide and polymerized by the polymerization reaction. The mechanical strength of the material can be improved.

On the other hand, the medical tube includes a tube for injecting or extracting drugs, biological fluids, etc. from the body, and a catheter inserted into the body for examination and treatment. Specifically, the tube is provided with a tube such as a liquid tube, a nutritional tube, a peritoneal dialysis tube, a blood transfusion tube, a urine tube bag or the like, a blood circuit for hemodialysis, Circuit tubes for use in blood circuits for replacement, and materials for medical applications such as transmission tubes. The material transfer tubing may be, for example, a tube attached to a multiple blood bag, a tube used to connect the aspirator to the catheter, and the like. In addition, catheters include catheter catheters, gastric catheters, suction catheters, and the like.

Such a tube is required to have position adjustability for the operation of the operator to be surely transmitted from the base to the distal end, such as insertion and withdrawal of a blood vessel, and pressure resistance when circulating a drug solution or the like therein. In addition, a press-fit property is also required so that the pressure input of the practitioner can be surely transmitted from the proximal end side to the distal end side in order to advance the inside of the blood vessel by achieving torque transfer for reliably transmitting the rotational force applied at the base portion of the catheter tube.

In order to obtain a catheter tube having the above-described characteristics, there is known a method of constructing a catheter tube by covering an outer layer in a state where a strand is wound or coiled in a coil shape as a stiffener layer in an inner layer tube. For example, Korean Patent Registration No. 10-1314714 discloses a method of manufacturing a catheter tube for medical use by forming a reinforcing material layer braided with metal strands. Japanese Laid-Open Patent Publication No. 2010-537793 discloses a configuration in which a carbon-related material such as carbon nanofibers and carbon nanotubes is used as a reinforcing material of a medical tube.

Korean Patent No. 10-1314714 Japanese Patent Laid-Open No. 2010-537793

The object of the present invention is to provide a graphene oxide / polyurethane composite which is excellent in compatibility with polyurethane and has improved mechanical properties as compared with polyurethane, and can be used as a reinforcing material for supplementing mechanical properties of a matrix made of polyurethane .

Another object of the present invention is to provide a method for producing a graphene oxide / polyurethane composite by an in-situ method without phase separation.

Another object of the present invention is to provide a medical tube having improved pressure resistance using the graphene oxide / polyurethane composite as a reinforcing material.

To this end,

Graphene oxide / polyurethane composite in which graphene oxide and polyurethane are chemically bonded.

Also,

A first step of reacting graphene oxide with a diisocyanate to prepare an isocyanate terminal graphene oxide,

A second step of reacting the isocyanate terminal graphene oxide with a polyol,

And a third step of subjecting the product of the second step to a chain extension reaction using a chain extender and simultaneously reducing graphene oxide. The present invention also provides a method for producing a graphene oxide / polyurethane composite.

Also,

In a medical tube formed of at least two layers,

The hollow tube-shaped inner layer

An outer layer formed on the inner layer and comprising the graphene oxide / polyurethane composite of claim 1;

And a medical tube.

According to the present invention, application of a graphene oxide / polyurethane composite excellent in compatibility with polyurethane to an outer layer of a medical tube can be expected to improve the mechanical strength and improve the pressure resistance.

1 is a flowchart illustrating a process for producing a graphene oxide / polyurethane composite according to an embodiment of the present invention.
2 is a photograph showing the result of observation of graphene oxide prepared in Example 1 by a transmission electron microscope.
Fig. 3 shows the results of X-ray diffraction analysis of the graphene oxide prepared in Example 1. Fig.
FIG. 4 is a graph showing the results of Raman analysis after reducing EDA by adding EDA as a reducing agent to graphene oxide prepared in Example 1 at 80 ° C. for 30 minutes.
5 shows the results of FT-IR measurement of graphene oxide prepared in Example 1 and graphene oxide before and after an isocyanate compound reaction.
Fig. 6 shows the results of FT-IR measurements of Examples 1 to 3 and Comparative Example 3. Fig.
Fig. 7 shows XPS analysis results of Examples 1 to 3 and Comparative Example 3. Fig.
8 shows the TGA analysis results of Examples 1 to 3 and Comparative Example 3.
9 shows the DSC analysis results of Examples 1 to 3 and Comparative Example 3.
10 is a graph showing the results of a T-type peel test after the urethane of Comparative Example 1 and the graphene oxide / polyurethane composite samples of Examples 1 to 3 were prepared in accordance with the KS-11339 standard.

Hereinafter, the present invention will be described in more detail.

Grapina Oxide / Polyurethane composite

The composite of the present invention is chemically bonded to graphene oxide and polyurethane. Specifically, the hydroxy groups present in the graphene oxide are converted to urethane bonds to form a complex with the polymer chains.

Graphene oxide has functional groups such as hydroxyl group, epoxy group and carboxyl group, and has a distance between layers that is longer than the interlayer distance of graphite. This functional group forms a complex through chemical bonding with polyurethane by in-situ method.

According to one embodiment of the present invention, graphene oxide is reduced graphene oxide (RGO) through chemical reduction or heat treatment of graphene oxide.

In one embodiment of the present invention, the content of graphene oxide may be 0.01 to 20 wt% of the total amount of the composite. If the content of graphene oxide is less than the above range, the effect of improving mechanical properties through complexation is insignificant. On the contrary, when the content exceeds the above range, the mechanical strength is drastically lowered.

Grapina Oxide / Polyurethane composite manufacturing method

The graphene oxide / polyurethane composite according to the present invention comprises

A second step of reacting the isocyanate terminal graphene oxide with a polyol,

And a third step of subjecting the product of the second step to a chain extension reaction using a chain extender and simultaneously reducing graphene oxide.

Each step will be described in detail below.

Step 1) First, an isocyanate-terminated graphene oxide is prepared by reacting graphene oxide with a diisocyanate.

When the solid phase graphene and the liquid phase polyurethane are combined, there is a problem that phase separation occurs. Therefore, in the present invention, a hydroxy group of graphene oxide is reacted with a diisocyanate to form a urethane bond, and both graphene oxide and diisocyanate can be compounded well without phase separation as a solid phase.

Diisocyanate Not specifically limited, those used in the technical field can be used. According to one embodiment of the present invention, there is provided a process for producing a diisocyanate compound, which comprises reacting 2,4-toluene diisocyanate, methylene bisdiphenylenediisocyanate, toluene diisocyanate, isophorone diisocyanate, 1,6-hexane diisocyanate, methylene biscyclohexyl diisocyanate, Or a combination thereof.

The reaction may be carried out at 60 to 100 ° C for 1 to 5 hours.

The reaction temperature is preferably from 60 to 100 ° C. If the reaction temperature is less than 60 ° C., the reactivity is lowered. If the reaction temperature is more than 100 ° C., the addition reaction is undesirably formed.

Further, the reaction time varies depending on the temperature and the amount of the catalyst.

The catalyst may be an organic polyvalent metal compound, bismuth octoate, dibutyltin dilaurate, stannus dilaurate, or the like.

Step 2) Next, the isocyanate-terminated graphene oxide is reacted with the polyol.

The polyol which can be used includes at least two hydroxy groups. The specific kind is not particularly limited in the present invention, but one kind selected from the group consisting of a polyether polyol, a polyester polyol, a polyester ether polyol, It is possible.

According to one embodiment of the present invention, the polyol may be selected from the group consisting of polyethylene glycol, polypropylene glycol, polyester polyol, polycaprolactone diol, polycarbonate diol, and polytetramethylene ether glycol.

Step 3) Next, the product of the second step is subjected to a chain extension reaction using a chain extender, and at the same time, the graphene oxide is reduced.

The chain extender may be a chain extender widely used in the art. According to one embodiment of the present invention, there is provided a process for the preparation of a compound represented by the general formula (1), which comprises using one selected from triethyltetramine, triethylamine, 1,3-diaminopropane, 1,4-diaminobutane, ethylenediamine, hexamethylenediamine and cadaverine The graphene oxide can be reduced simultaneously with the chain extension reaction.

Thus, in one embodiment of the present invention, instead of reacting reduced graphene oxide (RGO) with a diisocyanate through chemical reduction or heat treatment of the graphene oxide, the graphene oxide is reacted with a diisocyanate or a polyol The following chain extender is used to simultaneously reduce the chain extension. Therefore, reduction of the hydroxyl group reacting with the diisocyanate by reduction can be minimized.

Each of the reaction conditions is not limited to the present invention, but may be suitably selected by employing temperature, pressure, time, atmosphere, and the like by a person skilled in the art.

Through this reaction, the hydroxy groups present in the graphene oxide are converted to urethane bonds to form a graphene oxide / polyurethane composite in which the graphene oxide and the polyurethane are chemically bonded.

Medical Tubes

The medical tube of the present invention improves the pressure resistance by using a graphene oxide / polyurethane composite excellent in compatibility with polyurethane as a reinforcing material.

A medical tube of the present invention is a medical tube formed of at least two layers comprising an inner layer in the form of a hollow tube and an outer layer formed on the inner layer and comprising a graphene oxide / polyurethane composite.

Wherein the outer layer means the layer farthest from the center of the tube section and the inner layer means the layer closest to the center of the tube section. One or more intermediate layers may be formed between the outer layer and the inner layer.

The material of the inner layer can be used without restriction as long as it is used as a medical tube material. According to one embodiment of the present invention, the inner layer may comprise one selected from the group consisting of polyvinyl chloride, polyurethane, polyolefin, styrene-butadiene copolymer, styrene-ethylene-butylene-styrene copolymer and thermoplastic elastomer .

The graphene oxide / polyurethane composites included in the outer layer are as described above.

In addition, the outer layer may comprise polyurethane.

Specifically, the content of the graphene oxide / polyurethane composite in the outer layer is 1 to 100% by weight. If the content of the complex is less than the above range, the effect of improving the pressure resistance is insignificant.

According to an embodiment of the present invention, a reinforcing layer formed by winding a reinforcing wire around the inner layer may be formed between the outer layer and the inner layer. Specifically, the reinforcing layer can be formed by braiding the reinforcing wire by coil winding or mesh formation.

At this time, the material of the reinforcing wire can be any material as long as it has sufficient rigidity to obtain a sufficient reinforcing effect. Specifically, it is possible to use various metal materials such as tungsten, stainless steel, nickel-titanium based alloy, steel, titanium, copper, titanium alloy or copper alloy, polyimide, polyamideimide or polyethylene terephthalate, polybutylene terephthalate, , Polyolefins such as polyethylene and polypropylene, rigid polyvinyl chloride, polyamide, polystyrene, thermoplastic polyurethane, polycarbonate, ABS resin, acrylic resin, polymethyl methacrylate, polyacetal, polyarylate, (P0M), high tensile polyvinyl alcohol, fluororesin, polyvinylidene fluoride (PVdF), polytetrafluoroethylene, polysulfone, polyethersulfone, polyether ketone, polyphenylene oxide, polyphenylene sulfide, aromatic poly Aramid and the like, carbon fibers, glass fibers and the like can be used.

The diameter of the reinforcing wire is such that a sufficient reinforcing effect can be obtained. For example, in the case of the metal material, the diameter is preferably about 10 nm to 50 m.

The medical tube according to the present invention includes the steps of extruding an inner layer using an extrusion apparatus, forming a reinforcing layer by winding a reinforcing wire around the inner layer, And then extruding the layer to produce a medical tube. The extrusion process and the reinforcing layer forming process are well known in the art, and thus a detailed description thereof will be omitted herein.

Hereinafter, preferred embodiments and experimental examples of the present invention will be described. However, the following examples are only preferred examples of the present invention, and the present invention is not limited by these examples.

Comparative Example 1 (Pristine PU)

A 3-necked round bottom flask was charged with an equivalent (NCO: Polyol) solution of polytetramethylene glycol (BASF), diisocyanate (2,4-Toluene Diisocyanate (TDI), Isophorone Diisocyanate (IPDI), Junsei) 2: 1 and TDI: IPDI 3: 1), and reacted in N ₂ phase at 60 ° C for 3 hours. As a solvent, 100 ml of acetone was added, and a small amount of water was added every time the viscosity increased and stirring was difficult. After 3 hours, EDA was added and reacted for 1 hour. Then, the sample was transferred to a 1-necked round bottom flask, distilled under reduced pressure, and the solvent was distilled off and concentrated.

Example 1 to Example 3

Grapina Oxide synthesis

2 g of expanded graphite prepared by irradiating expandable graphite with microwave for 10 seconds, and 200 ml of sulfuric acid were uniformly added to the expandable graphite, and the mixture was stirred at 300 rpm. The temperature of the reactor was set at 35 占 폚. Then, 12 g of KMnO ₄ was added in small portions and stirred for 3 hours. After the temperature of the reactor was lowered to 5 ° C, 30 ml of distilled water was added to the reactor at a rate of 1 ml / min, and the mixture was stirred until it was evenly mixed with brown. The resulting solution was diluted with 500 ml of distilled water and 200 ml of a 30 wt% aqueous solution of HCl was added. After rinsing the acid with a large amount of distilled water, a grape-like oxide water-dispersed solution in a thick form was taken by centrifugation. This solution was placed in a vacuum oven at 80 DEG C for 24 hours to blow off water to prepare a solid graphene oxide sheet.

Grapina Oxide / Preparation of polyurethane composites

The graphene oxide sheet was sampled as much as the reaction equivalent, placed in a beaker containing 100 ml of acetone, and dispersed by a homogenizer for 1 minute and an ultrasonicator for 3 hours. After the mouth 3 the solution was placed in a round bottom flask was added the isocyanate compound (2,4-Toluene Diisocyanate (TDI) , Isophorone Diisocyanate (IPDI), Junsei) N 2 Phase, 1 hour at 60 ℃ respectively, 2 hours, 3 hours Lt; / RTI >

After the reaction, the mixture was reacted for 3 hours with addition of polyol (Polytetramethylene glycol, BASF) and catalyst (Dibutyl tin dilaurate, TCI), and then EDA was added for 1 hour. Then, the sample was transferred to a one- Lt; / RTI >

division Detail NCO: Polyol TDI: IPDI PU GO Comparative Example 1 Pristine PU 2: 1 3: 1 100wt% 0 Example 1 NCO-GO
(Reaction time 1 hr) 99.9 wt% 0.1 wt% Example 2 NCO-GO
(Reaction time 2 hr) 99.9 wt% 0.1 wt% Example 3 NCO-GO
(Reaction time 3 hr) 99.9 wt% 0.1 wt%

Experimental Example 1: Complex analysis

end) TEM Analysis

A transmission electron microscope (JEM-2100F, Jeol LTD) was observed for the graphene oxide prepared in Example 1 and the results are shown in Fig.

As shown in FIG. 2, a few layers of graphene oxide were observed by TEM analysis of the produced graphene oxide.

I) XRD Analysis

The graphene oxide prepared in Example 1 was analyzed by X-ray diffraction (Mimiflex, Rigaku, 25 to 90 ° C). The results are shown in FIG.

Referring to FIG. 3, XRD analysis of dried graphene oxide revealed that the graphene oxide had a high intensity at a characteristic peak of graphene oxide at 10 °, and the purity of the graphene oxide thus prepared was confirmed.

C) Raman analysis results

EDA as a reducing agent was added to the prepared graphene oxide to confirm whether EDA (ethylene diamine), which is mainly used as a urethane reducing agent, participates in the reduction reaction of graphene oxide, followed by heating at 80 ° C. for 30 minutes, Respectively.

Referring to FIG. 4, after the EDA treatment, the G peak at 1600 cm ^-1 was down-shifted to confirm the reduction of graphene oxide by EDA. It was confirmed that EDA causes chain extension effect of urethane and reduction of graphene oxide.

D) Results of FT-IR measurement

FT-IR (Magna 550 series, Nicolet: 25 ° C, KBr) of graphene oxide was measured before and after the reaction with isopropoxide and isocyanate compound to confirm the graphene oxide-NCO reactivity. The results are shown in FIG. 5, after the reaction of graphene oxide with an isocyanate compound, urethane characteristics peaks of 2800 cm ^-1 (NH) and 1700 cm ^-1 (Carbonyl) were found, and 2270 cm ^-1 (NCO) peaks were found. As a result, it was confirmed that a urethane functional group was produced.

FT-IR of Examples 1 to 3 and Comparative Example 3 were measured, and the results are shown in Fig. Referring to FIG. 6, FT-IR spectra of the graphene oxide and urethane complexes at reaction times showed urethane characteristics peaks at 2800 cm ^-1 (NH) and 1700 cm ^-1 (Carbonyl) peaks, and peaks at 2270 cm ^-1 (NCO) Found.

hemp) XPS Measurement result

XPS analysis was performed for each reaction time in order to examine the change of the functional groups generated by the reaction time of graphene oxide and isocyanate, and the results are shown in FIG. Referring to FIG. 7, as the reaction time increases, the content of the NHC = O characteristic peak at 400 cm ^-1 is increased. As a result, the reaction between graphene oxide and the isocyanate compound increases as the reaction time increases Respectively.

bar) TGA & DSC Analysis

TGA and DSC analysis (Perkinelmer, TGA7 / DSC7, 30 ~ 500 ℃) were performed to investigate the thermal properties of the prepared graphene oxide-urethane composites. Referring to FIG. 8, TGA analysis showed that the thermogravimetric trends of similar types were observed in all kinds of samples.

As shown in FIG. 9, DSC analysis showed that all of the four samples showed a similar graph shape. The amount of heat absorbed at 30 to 180 ° C by the reaction time of the graphene-isocyanate compound is shown in Table 2 below.

Reaction time (hr) Example 1
(1 hours) Example 2
(2 hours) Example 3
(3 hours) Heat absorption (mW) -517 -331 -589

As can be seen from the results in Table 2, the reduction of the heat absorption and the curing reaction during the 2-hour reaction seem to be less than those of the other samples.

G) Mechanical properties

The urethane of Comparative Example 1 and the urethane-graphene composite samples of Examples 1 to 3 were prepared in accordance with the KS-11339 standard, and the T-type peel test was conducted. The results are shown in FIG. As a result of the analysis, it was confirmed that the mechanical strength of Example 3, in which the graphene-isocyanate reaction time was 3 hours, was higher than that of pure urethane, thereby improving the mechanical properties.

Claims

The complex of claim 1, wherein the hydroxy group present in the graphene oxide is converted to a urethane bond.

The method of claim 1, wherein the graphene oxide
Wherein the graphene oxide is reduced graphene oxide (RGO) through chemical reduction or heat treatment.

The composite of claim 1, wherein the content of graphene oxide is from 0.01 to 20% by weight of the composite.

A first step of reacting graphene oxide with a diisocyanate to prepare an isocyanate terminal graphene oxide,
A second step of reacting the isocyanate terminal graphene oxide with a polyol,
A third step of subjecting the product of the second step to a chain extension reaction using a chain extender and simultaneously reducing graphene oxide
Lt; RTI ID = 0.0 > 1, < / RTI >

6. The method of claim 5, wherein the first step comprises:
RTI ID = 0.0 > 1 < / RTI > to 5 hours.

6. The method of claim 5, wherein the diisocyanate is
Which is one selected from the group consisting of 2,4-toluene diisocyanate, methylene bisdiphenylenediisocyanate, toluene diisocyanate, isophorone diisocyanate, 1,6-hexane diisocyanate, methylenebiscyclohexyldiisocyanate, and combinations thereof .

The method of claim 5, wherein the polyol
Wherein the polymer is one selected from the group consisting of polyethylene glycol, polypropylene glycol, polyester polyol, polycaprolactone diol, polycarbonate diol, and polytetramethylene ether glycol.

The method of claim 5, wherein the chain extender is
Wherein the compound is one selected from the group consisting of triethylamine, triethylamine, triethylamine, triethylamine, triethylamine, triethylamine, triethylamine, triethylamine, triethylamine, triethylamine, triethylamine, triethylamine, triethylamine, triethylamine, triethylamine,

In a medical tube formed of at least two layers,
The hollow tube-shaped inner layer
An outer layer formed on the inner layer and comprising the graphene oxide / polyurethane composite of claim 1;
. &Lt; / RTI >

11. The method of claim 10, wherein the outer layer
Further comprising a polyurethane.

11. The method of claim 10, wherein between the inner layer and the outer layer
And a reinforcing layer formed by winding an inner layer with a reinforcing wire.

The method of claim 10, wherein the graphene oxide / polyurethane composite comprises
Wherein the hydroxy groups present in graphene oxide are converted to urethane bonds.

The medical tube according to claim 10, wherein the content of graphene oxide in the graphene oxide / polyurethane composite is 0.01 to 20% by weight.

The medical tube of claim 10, wherein the inner layer is one selected from the group consisting of polyvinyl chloride, polyurethane, polyolefin, styrene-butadiene copolymer, styrene-ethylene-butylene-styrene copolymer and thermoplastic elastomer. .