KR0167828B1 - Water dispersed curable polyurethane resin composition - Google Patents

Abstract

The present invention relates to a moisture-curable polyurethane resin composition, and more particularly, water-curable polyurethane resin useful as an orthopedic bandage made by prepolymerization of polyol, aromatic diisocyanate, trimethylolpropane, benzoyl chloride and dimethylolpropionic acid. It relates to a composition.

Description

Moisture Curable Polyurethane Resin Composition

The present invention relates to a moisture-curable polyurethane resin composition, and more particularly, water-curable polyurethane resin useful as an orthopedic bandage formed by prepolymerizing polyol, aromatic diisocyanate, trimethylolpropane, benzoyl chloride and dimethylolpropionic acid. It relates to a composition.

Conventionally, orthopedic surgeons have used bandages using gypsum as casts for osteopathic patients, but recently many bandages using synthetic resins, especially polyurethane resins, have been used due to many problems as follows. Problems with the use of gypsum are as follows: First, the heavy weight of the elderly may cause muscle and skeletal problems caused by long-term use. Second, because gypsum does not penetrate X-rays well, it is necessary to irradiate X-rays with high wavelengths. If they are used by pregnant women, newborns may have disorders. Not good at Third, the wound may worsen in the case of patients with trauma because sweat and air are poorly permeable. Fourth, due to the summer sweat and the like contains the possibility of odor and bacterial infection. Fifth, when removing the cast after use, gypsum powder may be blown in the air and deposited on the respiratory organs, which is not good for the environment.

In comparison, cast using polyurethane is difficult to obtain high strength due to the use of polyurethane resins. However, rather than maintaining high fracture strength in actual use, it is more appropriate to maintain appropriate elasticity while maintaining appropriate strength. I think it will help protect the patient. In addition, polyurethane cast has many advantages, for example, the material is light and does not impede the activity of the patient much, and it is easy to transmit X-rays, so it does not need to penetrate high X-rays, and has excellent permeability such as air and sweat. In some cases, showering is possible, and there is less risk of odor and bacterial infection, which is good for hygiene, and it is possible to make various colors by adding pigment, so it looks good, and when weaving and removing cast after use Edo is less harmful to humans due to dust and has the advantage of environmental factors that can reduce the amount of waste by complete incineration at disposal.

An overview of water support fees and synthesis methods for preparing polyurethane resins is described in detail in US Pat. No. 4,433,680.

In Korean Patent Publication No. 90-3365, hydrophilic ethylene oxide and surfactant polysiloxane are used to reduce adhesiveness and improve lubricity, but in this case, these additives dissolve when submerged in water to contaminate water. In some cases, due to excessive lubricity, some bubbles block the breathing holes.

In US Pat. No. 376,421, polymer particles such as polyacrylonitrile are used as additives to reduce foaming properties, but they have a particle form, which causes some impregnation in water.

U.S. Patent Nos. 4,667,661 and 4,774,937 describe the general content of polyols and polyisocyanates by reaction, and mention the use of increased lubricity to improve usability, and these additives are described in detail. have. However, in this method, there is a problem of maximizing the hydrophilic material or the siloxane-based material in order to improve lubricity and to improve lubricity in order to lower the kinetic friction coefficient.

In addition, there are many known methods for reducing the adhesiveness, and a general method is to first apply a resin to a substrate (i.e., glass fiber or polyester fiber knitting tape) and to apply a lubricant to the substrate, or to apply a hydrophilic material having a lubricating component. The method of reacting with an isocyanate-reacting substance or adding a lubricant as an adduct to the finished reactant as a resin is used.

As a general method for improving lubricity, macromolecules of hydrophilic materials such as ethylene oxide (-CH ₂ CH ₂ O-) or propylene oxide (-CH ₂ CH ₂ CH ₂ O-) and ethylene oxide ( -CH ₂ CH ₂ O-) the part a material (-CH ₂ CHCH ₂ O in the polymerization - as there may be a method of adding a CH ₂ CH ₂ O-), another method is the method using a steel ball surfactant It is becoming. As the type of the surfactant, a patent of a material of a silicon oxide (SiO ₂ ) series, a monomer polymerizing three or more SiO ₂ is used, and in some cases, silicon oxide is a substance that is not directly impregnated during synthesis and directly participates in the reaction. do.

The problem with the conventional method of improving lubricity is that the substance used as a lubricant does not participate in the reaction and remains as an unreacted monomer, so that the lubricant dissolves in water when the cast is used, causing water pollution. The excessive increase in slippery caused by excessive use may adversely affect workability.

Therefore, in the manufacture of the conventional moisture-curable polyurethane resin, the lubricant added to give lubricity dissolves in water when using cast, and the problem of fixing the resin on the applicator's gloves in fixing the cast. In the present invention, by limiting the composition and content ratio of the polyurethane resin composition to prepare a moisture-curable polyurethane resin composition with reduced adhesiveness and improved lubricity without adding a lubricant or through a separate lubrication process Was completed.

SUMMARY OF THE INVENTION An object of the present invention is to provide a polyurethane resin composition with reduced adhesiveness and improved lubricity and an orthopedic cast using the same.

Hereinafter, the present invention will be described in detail.

The present invention provides a water-curable polyurethane resin composition prepared by prepolymerization of 30 to 45% by weight of polyol, 50 to 70% by weight of aromatic diisocyanate, 0.01 to 0.1% by weight of benzoyl chloride and 0.3 to 3% by weight of dimethylolpropionic acid. It features.

The present invention also includes an orthopedic cast in which the moisture-curable polyurethane resin composition is coated on a substrate.

Referring to the present invention in more detail as follows.

The polyurethane resin composition of the present invention is a prepolymer obtained by prepolymerizing a polyol component and an aromatic diisocyanate component by a conventional polymerization method in the presence of a stabilizer and a catalyst.

As the polyol, one or a mixture of two or more selected from polyetherdiol, polyesterdiol, polycarbonatediol, and the like may be used. [JHSaunders, Polyurethane Chemistry and Technology], polyol used There may be slight changes in physical properties depending on the type of, but any may be used. Among the polyol components, it is preferable to use polyetherdiol, and polyether glycol is particularly preferably used among polyetherdiol, which is good in synthesis due to low viscosity at room temperature. It is because adhesive force is favorable. Next, it is preferable to use polyethylene glycol, which contains a hydrophilic group, which helps to improve the lubricity of the resin, but it is maintained at a solid state at room temperature. When used alone, high viscosity is maintained even after synthesis, which may cause processing problems. In the case of polyesterdiol (polyesterdiol) various physical properties are good, but may be a problem due to hydrolysis phenomenon. In the present invention, polycaprolactone having a molecular weight of 1000 to 2000 prepared by ring-opening and polymerizing ε-caprolactone may be used as the polyol component, and in particular, polycaprolactone having a molecular weight of 1250 may be used. Excellent physical properties. Polycaprolactone is a solid phase at room temperature, which may cause problems in actual use.However, this problem may be solved by controlling other synthetic variables such as the content of isocyanate and the type and amount of chain extender. In particular, in terms of physical properties, it is excellent in weather resistance and water resistance, and has the property of reducing adhesive properties. Therefore, the composition of the most preferred polyol component which can be used in the present invention is 80 to 95% by weight of polycaprolactone and 5 to 20% by weight of two or more mixtures selected from polyetherdiol and polyethertriol. The polyol component presented above is preferably contained in 30 to 45% by weight in the total polyurethane resin composition, if the content is less than 30% by weight, the lubricity is not good and if the content exceeds 45% by weight, the adhesive force is reduced.

As the aromatic diisocyanate component, a general liquid-diphenylmethane diisocytate (L-MDI) or diphenylmethane diisocytate (L-MDI) shown in US Pat. No. 4,433,680 is used. The aromatic diisocyanate component in the polyurethane resin composition is preferably contained in an amount of 50 to 70% by weight. If the content is less than 50% by weight, the viscosity becomes too high. If the content exceeds 70% by weight, the viscosity becomes too low. There is a problem with stability due to excessive use of tate.

In addition, in the present invention, polyether triol and trimethylolpropane having an average molecular weight of 300 to 1,000 may be used as a method for enhancing adhesion in addition to the polyol component and the aromatic diisocyanate component. They are preferably contained in an amount of 0.1 to 10% by weight in the polyurethane resin composition, when contained too much, the adhesive force is improved, but the viscosity may be high, causing problems in use.

In addition, benzoyl chloride (benzoyl chloride), which is generally used, was used as a storage stabilizer, which showed a clear storage stability effect when used, but there was a problem in use due to severe odor. Therefore, the present invention uses dimethylolpropionic acid (DMPA) together with benzoyl chloride as a method for increasing the storage stability effect and hydrophilic properties, thereby reducing the amount of benzoyl chloride used, so that water pollution according to excess additive content And some unpleasant odors of the substance itself, and DMPA contains a carboxylic acid group (-COOH), which is a hydrophilic component, to impart a lubricating effect. DMPA is used as a reactant, not as an additive, and also has a characteristic that it does not elute in water when immersed in water. The DMPA is contained in the polyurethane resin composition 0.3 to 3% by weight, if the content is less than 0.3% by weight does not have a role of storage stability and sufficient lubricating effect, when exceeding 3% by weight is not well synthesized and There is also a problem with use.

In addition, in the prepolymerization for preparing the polyurethane resin composition of the present invention, various kinds of catalysts, including those known in the art, may be used, and particularly preferably dimorpholinoethyl ether (DMDEE) or 4- [2. -(Dimethylamino) ethyl] morpholine (DMDEE). The amount is preferably 0.5 to 2 parts by weight based on 100 parts by weight of the polyurethane resin composition. The amount of the catalyst used is less than 0.5 parts by weight, and the curing time is long. If the amount is more than 2 parts by weight, the curing time is too fast and the storage stability is not good. Will result.

In addition, in the present invention, a pigment may be used to produce a color, and as the pigment, any of the organic pigments described in Korean Patent Publication No. 93-17559 may be used, and the amount thereof is used in an amount of 1 part by weight based on 100 parts by weight of the total resin composition. Is less than. In the present invention, a plasticizer such as dioctyl adipate (DPA) may be added to the organic pigment in an amount of 80 to 95 parts by weight based on 100 parts by weight of the whole pigment composition.

All of the substances listed above have been used in that they are harmless to the human body and are unlikely to cause strong dermatitis on contact with the body.

The above components were prepolymerized by a conventional polymerization method to prepare a prepolymer, which was then coated on a substrate to obtain a cast according to the present invention in the form of a tape, and the cast must be kept stable until use. In other words, the resin must not harden in a sealed state and must be completely hardened in a reasonable time when wetted with water or left in the air when in use.

The substrate used in the present invention is a knitting machine so that the cross yarns and the workings are woven in one direction so as to have a proper porosity, and casts useful for the use of curved surfaces are produced only when the substrate maintains the proper elasticity. Can be. Therefore, the material of the substrate useful as a cast may be a variety of chemical fibers such as glass fiber, polyester fiber, nylon fiber, acrylic fiber, or natural fiber, such as cotton, hemp, silk, etc. Although it may be used, in particular, the polyurethane resin composition of the present invention exhibits very excellent physical properties even when applied to glass fibers which have not undergone heat treatment after weaving. The pore size of the substrate is preferably about 150 to 250 mesh (mesh), and if the pores are too large, the hardness does not come out, and if the pores are too small, poor breathability.

In addition, if the amount of the polyurethane resin composition coated on the substrate is large, it can flow down, there is a lot of bubbles generated during use to block the pores, the cast does not exhibit the re-function, if the application amount is small, the adhesive strength is small and well Since the case of falling off occurs, the amount of the polyurethane resin composition applied to the substrate is preferably 40 to 60% of the total weight of the molded article. In addition, when the viscosity of the polyurethane resin is high during application, the problem of not penetrating deep into the substrate occurs, and even when the viscosity is too low, it is not buried in the substrate and flows down, resulting in a small coating amount. It is desirable to maintain 15000 center poises.

Polyurethane cast according to the present invention as described above is usually stored in an aluminum bag protected with air and moisture, taken out when used and soaked in water at room temperature for a while, then wound around the site of fractures and muscle damage, in order to maintain an appropriate form Rub with your hands and cover them to be fixed to your body. At this point, the reaction with water starts and the adhesive force and hardness increase. If the adhesiveness is too strong, it becomes difficult to form a shape because it is buried in the glove. Also, bubbles are generated by the generation of carbon dioxide gas by the reaction of isocyanate and water. When the foaming phenomenon increases, the resins that start to cure become entangled with each other and block pores of the porous cloth, thereby causing bad breathability. However, in the present invention, by using a method of changing the composition and content of the polyurethane resin composition without adding a lubricant and a separate lubrication process, bubbles are not generated, and slipperiness (lubrication) can be appropriately controlled, and workability is further improved. It was satisfactory and there was no problem in adhesion to the substrate surface, which could occur when curing with water occurred quickly.

In the present invention, the isocyanate content measuring method (NCO%) and the viscosity measuring method were used when preparing a prepolymer, that is, a polyurethane resin composition.

Isocyanate content measurement method shows the result of the completion of the reaction. If the NOC content is more than 15%, the synthesis is not completed yet. If the content is less than 10%, there are many side reactions, which adversely affects the overall physical properties and decreases the adhesion. Or higher viscosity may result in less sticking to the substrate surface during processing. The preferred isocyanate content is therefore 10-15%.

To explain in more detail the isocyanate content measurement method, first, weigh 2 to 5 g of the prepolymer synthesized in the flask to four decimal places, exactly 10 ml of 2N-dibutylamine is accurately followed and completely dissolved, and then isopropyl alcohol. Dilute. Bromophenol Blue was added as an indicator and titrated with 0.5 N hydrochloric acid (HCl) to find the endpoint at the point where it turned yellow, and the NCO% value was obtained by the following equation.

NCO% = [(amount of hydrochloric acid used in the blank test x amount of hydrochloric acid used in this test) × 2.101 × factor] / sample amount

In the above formula, 'public test' refers to the amount when tested without using a sample, and 'factor' refers to an error that may occur when preparing 0.5N-HCl.

Viscosity measurement is an indication of the degree of flowability (lubrication). The spindle is # 4 for a Brookfield RVT viscometer. The measurement temperature is 25 ℃, and the viscosity is measured after leaving for 30 minutes in a 25 ℃ oven so that the overall temperature of the liquid contained in the resin is maintained uniformly.

If the measured viscosity is higher than 15000 centipoise or lower than 5000 centipoise, it will adversely affect the operation.

Hereinafter, the present invention will be described in detail with reference to the following examples, but the present invention is not limited by the examples.

[Examples 1-10 and Comparative Examples 1-8: Preparation of Polyurethane Resin Composition]

While injecting nitrogen into the 1L reactor, the aromatic diisocyanate components shown in the following Tables 1 and 2 were added, the reaction temperature was maintained at 55-60 ° C, and the polyol components were added dropwise, but the temperature did not exceed 75 ° C. .

All synthesis was deemed complete when within ± 1% of the specified NOC% range. The reaction temperature was lowered to room temperature while stirring, a stabilizer component was added at room temperature, stirred for 30 minutes, and then the catalyst component was added and stirred for 10 minutes. And 1 part by weight of Cyanine Blue B-7800 (product of Songwon Color) containing a plasticizer (DOA) as a pigment was added to 100 parts by weight of the total resin composition.

The prepared polyurethane resin composition was packaged, and after one day, 3 inches of glass fiber GT-3 (manufactured by Daesung Fiber Co., Ltd.) was used as a substrate.

The substrate was coated with 45% of the polyurethane resin composition prepared above, and then sealed in an aluminum bag.

(1) L-MDI (Liquid-diphenylmethane diisocyanate): Hanyang BASF Products

(2) MDI (Diphenylmethane diisocyanate): Hanyang BASF Products

(3) Placel 212: manufactured by DICELL Co., Ltd.

(4) PPG-400 (Polypropylene glycol-400): Korea Polyol Products

(5) PPG-750 (Polypropylene glycol-750): Korea Polyol Products

(6) PPG-1000 (Polypropylene glycol-1000): Korean polyol product

(7) GP-400 (Polypropylene triol-400): Korean polyol product.

(8) GP-700 (Polypropylene triol-700): Korean polyol product.

(9) GP-750 (Polypropylene triol-750): Korean polyol product.

(10) GP-1000 (Polypropylene triol-1000): Korean polyol product.

(11) TMP (Trimethylolpropane): Youngwoo Chemical.

(12) PEAD (Polyethyleneadipate diol): Dongsung Chemical Co., Ltd.

(13) DMPA (Dimethylolpropionic acid): Japan Tokyo Chemical Industries.

(14) Benzoyl chloride (BC): Japanese physicochemical science

(15) DMDEE (Dimorpholinoethylether): manufactured by HUNTSMAN.

(16) DMAEMO [4- [2- (dimethylamino) ethyl] morpholine]: Tosoh Co., Japan.

Experimental Example

[Measurement of adhesion]

The polyurethane casts prepared in Examples 1 to 10 and Comparative Examples 1 to 8 were cut into three pieces of 1.5 cm x 1.5 cm in size, and the adhesiveness was measured according to the following test method. 3 is shown.

The measuring method measures the degree of adhesive force of resin coated on a base material, and can easily obtain the adhesive force according to the value as a numerical value. The name of this machine is probe adhesion test and the test method is AS Test Method D-2979 (adhesiveness of pressure sensitive adhesives using a prober machine).

[Test Methods]

1. Material and test conditions

When using test sample, it should be kept at 21 ~ 25 ℃ for 2 hours. The water used in this test should be soft water maintained at 22-25 ℃. The test temperature should be maintained at 21-25 ℃, and the relative humidity should be prepared under the conditions of 45-55 ℃.

2. Appliance

The PROVE adhesion test consists of a drive unit, contact surface, instrumentation unit, thermostat, and operation panel. The instrumentation part consists of 10, 20, 50, 100, 200, 500, and 1000 g / cm 2 depending on the measured load.The sample holding link (LINK) consists of 20, 80, 180 g of 2, 4, 10, 20g weights. have. In the case of 200 g / cm 2 or more, 20, 80, 180 g of additional weight is added to 20 g of 100 g / cm 2 to make 200, 500 and 1000 g / cm 2, respectively. At this time, the thermostat maintains the proper temperature.

3. How to

① Set contact time and peel strength.

② Open the bag containing the test sample and immediately cut the sample to 1.5cm × 1.5cm in the length direction.

③ After immersing the cut sample in soft water of 21-25 ℃, take it out after 3 seconds and squeeze it out.

④ Attach the sample holding link (LINK) and cover the top with tape.

⑤ Press the start switch to lower the sample stage and compress it under any test load on the adhesive side of the sample and the upper side of the probe. The sample holding link is held by the probe, and the contact time is calculated when the contact is dropped from above.

⑥ When the contact time is completed, the required force is displayed as the probe falls from the sample bonding surface.

⑦ As the sample hardens with time, it is regarded as the result of one test that results in the highest adhesive strength between 2 and 5 minutes after opening the package.

⑧ Perform three times as above and average the results.

In the results of Table 3, the stronger the average adhesiveness, the poorer the adhesiveness and the worse the workability. The polyurethane resin compositions of Examples 1 to 10 according to the present invention have an average adhesiveness of 20 to 30 and are currently commercially available. Compared to Delta-Lite S, the adhesiveness is also very low, indicating workability.

Claims (9)

A water curable polyurethane resin composition prepared by prepolymerization of 30 to 40% by weight of polyol, 50 to 70% by weight of aromatic diisocytate, 0.01 to 0.1% by weight of benzoyl chloride and 0.3 to 3% by weight of dimethylolpropionic acid. . According to claim 1, wherein the polyol is water-curable poly, characterized in that consisting of 80 to 95% by weight of polycaprolactone, and 5 to 20% by weight of one or a mixture of two or more selected from polyetherdiol and polyethertriol. Urethane Resin Composition. The moisture-curable polyurethane resin composition according to claim 1, wherein the aromatic diisocyanate is liquid-diphenylmethane diisocytate, diphenylmethane diisocytate or a mixture thereof. The method of claim 1, wherein the catalyst during the prepolymerization reaction uses dimorpholinoethyl ether or 4- [2- (dimethylamino) ethyl] morpholine in an amount of 0.5 to 2 parts by weight based on 100 parts by weight of the resin composition. A moisture curable polyurethane resin composition. The moisture-curable polyurethane resin composition according to claim 1, wherein less than 1 part by weight of a normal pigment is added to 100 parts by weight of the resin composition. The moisture-curable polyurethane resin composition according to claim 1, wherein the resin composition has a viscosity of 5000 to 15000 centipoise and an NCO% of 10 to 15. An orthopedic cast formed by coating and molding the moisture-curable polyurethane resin composition substrate of claim 1. The cast for orthopedic according to claim 7, wherein the moisture curable polyurethane resin composition is coated in the range of 40 to 60% of the total weight of the cast. 8. The cast of orthopedic according to claim 7, wherein the substrate is glass fiber which is not heat treated after being served.