KR100428748B1 - Water-setting polyurethane resin composition for casting tape - Google Patents

Abstract

The present invention relates to a water-curable polyurethane resin composition for casting tape, and more particularly, polyether glycol and polyester glycol are mixed in a specific ratio with a polyol component, and a certain amount is contained in the entire polyurethane resin composition to produce a water-curable polyurethane resin. By preparing the composition, the present invention relates to a hydrosetting polyurethane resin composition for casting tape, which is excellent in lubricity, molding property and strength, and can reduce the phenomenon of the resin being localized when used in an orthopedic casting tape.

Description

Water-setting polyurethane resin composition for casting tape

The present invention relates to a water-curable polyurethane resin composition for casting tape, and more particularly, polyether glycol and polyester glycol are mixed in a specific ratio with a polyol component, and a certain amount is contained in the entire polyurethane resin composition to produce a water-curable polyurethane resin. By preparing the composition, the present invention relates to a hydrosetting polyurethane resin composition for casting tape, which is excellent in lubricity, molding property and strength, and can reduce the phenomenon of the resin being localized when used in an orthopedic casting tape.

Conventionally, gypsum bandages have been used as a method for fixing fractures, but the procedure is inconvenient and heavy, and the air permeability is poor and the comfort is poor and the X-ray permeability is poor. There was a problem that was difficult to pinpoint the progress. Therefore, in recent years, in order to supplement the disadvantages of the gypsum bandage has been replaced by orthopedic splint prepared by applying a polyurethane resin on a flexible support such as glass fiber substrate.

U.S. Patent Nos. 3,241,501, 3,881,473, 4,667,611 and 4,774,937 refer to UV curable polyurethane resins. However, this UV curing method requires an ultraviolet lamp and has a disadvantage of long curing time, and thus does not have a great effect on commercialization.

In order to solve this problem, U.S. Patent Nos. 4,131,114, 4,502,479, 4,376,438, and 4,411,262 disclose a casting tape coated with a glass fiber substrate with a hydrocurable polyurethane resin. In addition, US Patent No. 4,433,680 discloses a catalyst that effectively acts on the curing reaction of the hydrocurable polyurethane resin.

In the known art, glass fiber knitted fabric is mainly used as the fibrous support used in the synthetic casting tape. Glass fiber knitted fabrics have excellent fracture and impact strengths compared to general gypsum bandages and are recognized as suitable materials for casting tape supports. However, the glass fiber knitted fabric has a low elongation of the fiber itself and thus lacks consistency with the fractured part of the body, as well as tearing of clothing and skin in this part after hardening due to loosening of the loop at the part cut after casting or during manufacture of the product. Has problems such as.

On the other hand, U.S. Patent No. 4,667,661 discloses the improvement of the lubricity by introducing polyethylene polyols or polysiloxanes having a plurality of hydrophilic groups in the water-curable polyurethane resin, but the resin may cause water pollution by recording in water during processing. there is a problem. In addition, US Pat. No. 4,655,208 discloses a method of improving the curing rate by introducing a hydrophilic polyol in a hydrocurable polyurethane resin, but the casting tape is not completely incinerated after use by using a glass fiber substrate, thereby preventing environmental pollution. When cut, glass fiber dust can penetrate the patient's skin and cause itching or acute dermal toxicity.

In addition, US Pat. No. 4,937,146 uses mineral oils and natural oils to improve adhesiveness and lubricity, but there is a problem in that the oil escapes from the substrate and deteriorates in appearance during long-term storage.

Korean Patent Application No. 95-34111 mentions a method for improving lubricity by adding dimethylolpropionic acid to a hydrocurable polyurethane resin, but it does not loosen well during the procedure due to localization of the coated resin during long-term storage. This casting tape has a problem of bringing color unevenness.

Thus, the present inventors to solve the above problems by mixing polyether glycol and polyester glycol in a specific ratio as a polyol component by containing a certain amount in the entire polyurethane resin composition to produce a casting-type polyurethane resin composition for casting tape The present invention has been completed.

Accordingly, an object of the present invention is to provide a hydraulically curable polyurethane resin composition for a casting tape that is excellent in lubricity, molding property and strength, and can reduce localization of the resin due to resin flowability during long-term storage. .

The present invention relates to a polyurethane resin composition comprising a polyol component and an aromatic diisocyanate as a main component, wherein the polyol component contains 20 to 40 wt% of a mixture (1: 1 to 3: 1 weight ratio) of polyether glycol and polyester glycol. It is characterized by the water-curable polyurethane resin composition for casting tape.

Referring to the present invention in more detail as follows.

In the present invention, polyether glycol and polyester glycol are mixed in a specific ratio as a polyol component to be contained in a predetermined amount in the entire polyurethane resin composition to prepare a hydrocurable polyurethane resin composition, which is excellent in lubricity, molding property and strength, as well as orthopedics The present invention relates to a water-curable polyurethane resin composition for a casting tape that can reduce the phenomenon that the resin is localized when used in the casting tape.

Generally, the hydrocurable polyurethane resin composition contains a polyol component and a diisocyanate as main components.

In the present invention, it is preferable to contain 20 to 40% by weight of the polyol component, which is the greatest feature in the hydrocurable polyurethane resin composition, of a mixture of polyether glycol and polyester glycol in a weight ratio of 1: 1 to 3: 1 in the total resin composition. Do. If the content is less than 20% by weight, the viscosity is low, so that the storage stability is bad, and if the content is more than 40% by weight, the viscosity is high and there is a problem in processing. In particular, as the polyether glycol, a high molecular weight polypropylene triol having a weight average molecular weight of 2,000 to 3,000 and a low molecular weight polypropylene triol having a weight average molecular weight of 200 to 1,000 are mixed at a weight ratio of 1: 1 to 4: 1. It is good to use. And it is good to use the polyester glycol whose weight average molecular weights are 1,000-2,000. If the mixing ratio of the polyether glycol and polyester glycol outside the above range there is a problem that the storage stability is not good. In addition, when the mixing ratio of the high molecular weight polypropylene triol and the low molecular weight polypropylene triol used as the polyether glycol is outside the above range, there is a problem that the compressive strength is weak. In addition, if the weight average molecular weight of the polyester glycol is less than 1,000, the viscosity is high, there is a problem in processing, if it exceeds 2,000 there is a problem that the compressive strength is lowered.

In the present invention, the high molecular weight (Mw 2,000 to 3,000) polypropylene triol imparts elasticity to the resin by acting as a soft segment in the water-curable polyurethane resin, and the low molecular weight (Mw 200 to 1,000) poly Propylene triol improves compressive strength by acting as a hard segment in the resin. In addition, polyester glycols act as soft segments in the resin, increasing adhesion between substrates. As described above, the present invention is used as a polyol component by mixing a specific range of polypropylene triol and polyester glycol in a specific ratio to improve the lubricity, molding and strength to the hydrocurable polyurethane resin as well as orthopedic casting tape When used in the present invention reduces the phenomenon that the resin is localized.

It is preferable to contain 50-65 weight% of diisocyanate compounds in all the resin compositions, and if the content is less than 50 weight%, it will become high viscosity, and when it exceeds 65 weight%, there exists a problem that a viscosity becomes low. The diisocyanate compound is a polyurethane [Polyurethanes; Chemistry and Technology II, p453-607, p609-659, Interscience Publishers] may be used any of the diisocyanate known. Especially, it is preferable to use liquid diphenylmethane diisocyanate (L-MDI), diphenylmethane diisocyanate (MDI), etc. preferably.

It is preferable to contain 0.5 to 3% by weight of the chain extender in the total resin composition, and if the content is less than 0.5% by weight, there is a problem of low compressive strength. have. Examples of the chain extender include 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentylglycol, propylene glycol, ethylene glycol, and the like having two or more hydroxyl groups in a molecule. Reserol, trimethylolethane, trimethylolpropane, pentaerythritol, sorbose, sorbitol, and the like may be used alone or in combination, preferably 1,3-butanediol, 1,4 Butanediol, ethylene glycol, glycerol or trimethylolpropane may be used. The chain extender improves compressive strength by acting as a hard segment in the resin.

In the present invention, it is preferable to contain 0.01 to 1% by weight of a stabilizer which serves to prevent premature curing reaction of the hydrocurable polyurethane resin during the storage of the casting tape in the total resin composition, and if the content is less than 0.01% by weight Stabilization effect cannot be obtained during storage, and if it exceeds 1% by weight, there is a problem of lowering reactivity. As the stabilizer, benzoyl chloride and triethylphosphate or tributyl phosphate may be used. Preferably, triethylphospate or phosphoric acid based on phosphoric acid rather than benzoyl chloride, which is highly toxic and odorous, may be used. It is preferable to use tributyl phosphate.

In the present invention, the hydrocuring catalyst which serves to promote the reaction between the polyurethane resin and water is preferably contained in the total resin composition of 0.7 to 2% by weight, and if the content is less than 0.7% by weight, the curing time is slow, If it exceeds 2% by weight, there is a problem in the work hardening too fast, the long-term storage stability is bad. Examples of the hydrocuring catalyst include amine compounds such as triethylamine, dimethylethanolamine, tetramethyl-1,3-butanediamine, bis-2-dimethylaminoethyl ether and triethylenediamine, stenosoctoate and dibutyl tin di. Metal compounds such as laurate and dibutyl tin acetate, N-methyl morpholine, N-ethyl morpholine, dimoporn diethyl ether, dimoporn diethoxyethane, bis (2,6-dimethylmorpholino) ethyl ether, and mortar Morpholine compounds such as linoethyl- (2,6-dimethylmorpholinoethyl) ether and 1- (2-morpholinoethoxy) -2-2- (2,6-dimethylmorpholinoethoxy) ethane; It can be used, it is preferable to use dimorpholino diethyl ether (DMDEE).

The lubricant is preferably contained in an amount of 2 to 15% by weight in the total resin composition, and if the content is less than 2% by weight, the lubricity is poor. If the content is more than 15% by weight, the lubricant is good. There is a problem in that the compressive strength is worsened by lowering the adhesion between the substrates. The lubricant is a natural product, liquid low viscosity mineral oil (hydrogenated butylene ethylene stylene copolymer), hydrogenated ethylene propylene styrene styrene copolymer (hydrogenated ethylene propylene) which is not harmful to the human body High viscosity mineral oil containing stylene copolymer) can be used. In addition, the lubricant is preferably used by mixing a low viscosity mineral oil having a viscosity of 100 to 200 cps and a high viscosity mineral oil having a viscosity of 18,000 to 22,000 cps at a weight ratio of 1: 9 to 9: 1 at 25 ° C. The present invention is used by mixing the low viscosity mineral oil and high viscosity mineral oil in the above range to impart lubricity in the resin to provide a convenient and soft feeling to the patient when applied to the casting tape to improve the physical fitness, the detachment of the resin from the substrate The phenomenon can be improved.

Since the resin composition which consists of said component has a viscosity of 40,000-60,000 cps / 30 degreeC, it has the favorable characteristic of resin flow.

On the other hand, the present invention includes an orthopedic casting tape molded by coating the substrate with the curable polyurethane resin composition according to the present invention containing the above-mentioned composition in a conventional manner. At this time, the content of the hydrocurable polyurethane resin composition to be applied to the substrate is preferably used 35 to 60% by weight, more preferably 45 to 55% by weight relative to the total casting tape. When the content of the added hydrocurable polyurethane resin composition is less than 35% by weight, the crushing strength is lowered after curing. When the content of the hydrocurable polyurethane resin composition is less than 35% by weight, the resin is unevenly distributed during storage due to the excessive amount of resin. It is not preferable in appearance. In addition, the substrate is environmentally friendly to use polyester having an elongation of 20 to 50%, and may be harmful to the human body.

Such a present invention will be described in more detail based on the following examples, but the present invention is not limited thereto.

Example 1 Preparation of Hydrosetting Polyurethane Resin

Next to the composition as shown in Table 1 to prepare a hydrocurable polyurethane resin composition in the following manner.

The isocyanate component was added while nitrogen was injected into the reactor, the reaction temperature was maintained at 55 to 60 ° C., and then the polyol component was added dropwise. The reaction was assumed to be complete when the NCO% reached 14%. After the reaction was completed, the temperature was lowered to room temperature, a stabilizer was added, followed by stirring for 30 minutes, and then a catalyst was added thereto, followed by further stirring for 10 minutes. Then, a lubricant was added to prepare a final hydrocurable polyurethane resin.

Examples 4-6 and Comparative Examples 5-10. Casting Tape Preparation

The casting tape was prepared by applying the hydrocurable polyurethane resin composition prepared according to Examples 1 to 3 and Comparative Examples 1 to 4 to the polyester base in the amounts shown in Table 2 below. Casting tape was manufactured using a one-roll coating device and coated with a water-curable polyurethane resin while being coated with aluminum wrapping paper while preventing excessive tension on the substrate.

As a comparative example, Scotch Cast Plus (US 3M, Comparative Example 9) and Shinto-Cast (Kirschner Medical, Comparative Example 10), which are conventional casting tapes, were used.

Test Example 1.

Physical properties of the casting tapes of Examples 4 to 6 and Comparative Examples 5 to 10 were measured by the following methods, and the results are shown in Table 2 above.

1. Measurement of elongation of substrate

The casting tape was opened, cut about 10 cm, and pulled with normal force to calculate the elongation of the substrate by the following equations (1) and (2).

Length elongation (%) = (length-initial length when extended) / initial length * 100

Width elongation (%) = (length-initial length when it increased) / initial length * 100

2. Measurement of resin flow

The casting tape was opened and weighed, placed in a dried glass jar and filled with dry nitrogen to seal it. The sealed glass bottle was placed in a drying oven at 70 ° C., and after 5 days, only the casting tape was taken out to measure the glass bottle weight, and the resin flowability was calculated by the following equation (3).

3. Compressive strength measurement

The casting tape was opened, immersed in water at room temperature for 5-10 seconds, squeezed 2-3 times to remove excess water, and then wound 6 times in a 5 cm diameter cylinder to form a cylinder. After 5 minutes, the cured casting tape was removed from the cylinder and stored for 24 hours in an atmosphere with a relative humidity of 55 ± 5%. Then, the compressive strength was measured by a tensile tester. At this time, the crosshead descending speed of the tensile tester was 5 cm / min, and the load value received when the casting tape was pressed 1 cm was calculated and the unit was kg / cm.

4. Resin solubility measurement

The casting tape was opened, immersed in water at 23 ° C., squeezed three times to remove excess water, dried in an oven at 80 ° C. for 4 hours, and then calculated by Equation 4 below.

5. Measurement of coating amount of resin

Open the casting tape, cut it into 10 cm lengths, put it in a PE bottle containing 500 ml of acetone, squeeze it 10 times, dissolve the polyurethane resin coated on the surface, and wash it again with acetone 4 to 5 times to dry the weight of the substrate. Was measured and calculated by the following equation.

As shown in Table 2, the casting tapes of Examples 4 to 6 according to the present invention showed a strong strength by using a mixture of polypropylene triol and polyester glycol in a specific ratio as a polyol component, resin flow properties It was confirmed that the removal of the resin from the substrate to less than 8%, and the low-viscosity mineral oil and high-viscosity mineral oil was used as a lubricant to give the casting tape lubricity.

However, Comparative Examples 5, 6 and 8, which are casting tapes coated with a polyurethane resin when the polyol component is outside the scope of the present invention, do not impart elasticity to the resin due to the low content of high molecular weight polypropylenetriol. As a result, the adhesive strength between the substrates is not good, and Comparative Example 7 did not contain polyester glycol, and thus, it was confirmed that sufficient crosslinking was not formed, thereby obtaining a strength reinforcing effect.

Test Example 2.

The viscosity of the polyurethane resins prepared in Examples 1 to 3 and Comparative Examples 1 to 4 was measured using a Brookfield RVT viscometer having a spindle # 4. The temperature was measured at 30 ℃, the viscosity of the resin contained in the container was stored in a 30 ℃ oven for 30 minutes in order to maintain a uniform temperature and then measured the viscosity, the results are shown in Table 3 below.

As shown in Table 3, the polyurethane resin of Examples 1 to 3 according to the present invention has a viscosity of 40,000 to 60,000cps can be confirmed that the flowability of the resin does not flow down from the substrate, the scope of the present invention The comparative example deviated from the low viscosity was confirmed that there is a problem that the resin is detached from the substrate.

As described above, the water-curable polyurethane resin composition for casting tape according to the present invention is a polyol component by using a mixture of polyether glycol and polyester glycol of a specific molecular weight range in a certain ratio, the strength is strengthened, the resin during long-term storage In addition to reducing the localization of the resin due to flowability, and improve the problems of lubricity and water pollution, as well as excellent molding properties in the curved area can be useful for orthopedic casting tape.

Claims (4)

A polyurethane resin composition comprising a polyol component and an aromatic diisocyanate as a main component, wherein the polyol component contains 20 to 40 wt% of a mixture (1: 1 to 3: 1 weight ratio) of polyether glycol and polyester glycol. Hydrocurable polyurethane resin composition for casting tapes. The method according to claim 1, wherein the polyether glycol is used by mixing a weight average molecular weight of 2,000 to 3,000 and a polypropylene glycol of 200 to 1,000 in a weight ratio of 1: 1 to 4: 1, the polyester glycol is a weight average molecular weight The thing of 1,000-2,000 is used, The water-curable polyurethane resin composition for casting tapes characterized by the above-mentioned. Orthopedic casting tape, characterized in that formed by coating the hydrocurable polyurethane resin composition according to claim 1 on a substrate. The orthopedic casting tape according to claim 3, wherein the substrate is polyester having an elongation of 20 to 50%.