JPH02102215A - Moisture-curable urethane prepolymer composition and moisture-curable fixing material for medical use - Google Patents

Abstract

PURPOSE:To provide the title compsn. with excellent storage stability and adjustable curing time in use by compounding a urethane prepolymer having isocyanate groups on its terminals with dimorpholino-triethyl ether as a curing catalyst. CONSTITUTION:A urethane prepolymer having isocyanate groups on its terminals is prepd. by reacting a diisocyanate compd. (e.g., 2,4-toluene diisocyanate) with a polyol compd. (e.g., polypropylene glycol). A moisture-curable urethane prepolymer compsn. is prepd. by compounding said urethane prepolymer with dimorpholinotriethyl ether of the formula as a curing agent. It is possible to prepare a moisture-curable fixing material for medical use suitable for a plaster cast for orthopedic surgery by preparing a reticular supporting material carrying this resin compsn.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention can be used as a paint, an adhesive, and the like. Moisture-curing urethane prepolymer composition with excellent storage stability and moderate curing speed after immersion in water, and use as an orthopedic cast bandage by impregnating a mesh support with the urethane prepolymer composition The present invention relates to a medical fixative having excellent storage stability and a reasonable curing speed.

(Prior Art) Moisture-curable urethane prepolymer compositions are used as paints, adhesives, etc., and in recent years, they have been applied to orthopedic cast bandages by supporting them on net-like supports such as glass cloth and polyester cloth. is increasingly being used as a medical fixative.

The following are the essential requirements for an orthopedic cast bandage: - It must be moistened by soaking it in water and set on the affected area, and then harden in an appropriate amount of time. - The cast bandage must have appropriate strength after hardening. The product does not change or deteriorate even if it is stored as a cast bandage for a long period of time.

Among the above essential requirements, ■ has been formulated for some time by devising the molecular structure of the urethane prepolymer, but the essential requirements ■ and ■ have contradictory properties, so the requirements are not fully met. Most things are
It is extremely common for products to change shape and become unusable while being stocked and stored by urethane prepolymer manufacturers, medical fixing material manufacturers, medical supplies dealers, and clinics.

As for specific changes in product form, in most cases the urethane prepolymer composition supported on glass cloth, polyester cloth, etc. solidifies during inventory and storage.

It may be poorly packaged, absorb moisture in the air and harden before being used as an orthopedic cast dressing, but the addition of a curing catalyst aims to meet the essential requirements ■ If the amount is increased, the rate of progress of the allophanate reaction in the urethane prepolymer increases during inventory and storage, resulting in solidification due to self-polymerization.

(Objective of the Invention) The object of the present invention is not only to satisfy the above-mentioned essential requirement (■) as an orthopedic cast bandage, but also to satisfy the contradictory characteristics (■) and (2) which are lacking in conventional products. It is an object of the present invention to provide a moisture-curable urethane prepolymer composition and a medical fixing material that can simultaneously satisfy these requirements.

(Structure of the Invention) That is, 1. The present invention is characterized in that: (1) it contains a urethane prepolymer having an -NCO group at the end, which is composed of a diisocyanate compound and a polyol compound, and dimorpholinotriethyl ether having the following chemical structure as a curing catalyst. and (2) a resin containing a urethane prepolymer having an -NCO group at the terminal consisting of a diisocyanate compound and a polyol compound and dimorpholinotriethyl ether having the following chemical structure as a curing catalyst. A moisture-curable medical fixing material characterized in that the composition is supported on a net-like support.

The present invention will be explained in detail below.

First, the diisocyanate compound, which is one of the compounds constituting the urethane prepolymer, which is the main resin component in the urethane prepolymer composition, will be described.

The molecular structure of the diisocyanate compound that can be used in the moisture-curing urethane prepolymer composition and moisture-curing medical fixing material of the present invention is not particularly limited, but aromatic and group diisocyanate compounds are particularly preferred.

Specific examples of aromatic diisocyanate compounds include 2
．． 4-) toluene diisocyanate, 2°6-toluene diisocyanate, isomer mixtures thereof, 2.4-diphenylmethane diisocyanate, 1,4-diphenylmethane diisocyanate, 2.2-diphenylmethane diisocyanate), 4.4°-diphenylmethane These include diisocyanates and mixtures thereof.

Among them, it is particularly preferable to use 4,4'-diphenylmethane diisocyanate.

As the other polyol compound constituting the urethane prepolymer, a polyol having a primary hydroxyl group is particularly suitable.

Specific examples of polyols having primary hydroxyl groups include polytetramethylene oxide glycol, polypropylene glycol, polyethylene glycol, and polyester polyols (such as polycaprolactone polyol).

Among them, two grades of various prices are mass-produced,
Polypropylene glycol is particularly preferred because it is easily available.

Among these polyol compounds, those having two hydroxyl groups in one molecule and a number average molecular weight in the range of 400 to 2,500, or those having three hydroxyl groups in one molecule and a number average molecular weight in the range of 400 to 2,500. Particularly preferred are those in the range of 2,500 to 2,500, prepared so that the average number of hydroxyl groups per molecule is 2 or more and 2.5 or less.

Therefore, it is also possible to use alone one having two hydroxyl groups in one molecule and having a number average molecular weight in the range of 400 to 2,500.

If the average hydroxyl group per molecule is less than 2, inocyanate groups are not necessarily present at the ends of the urethane prepolymer, which limits the elongation of the molecule due to reaction with water. It becomes impossible to form long-chain molecular structures.

Therefore, the polymer after curing due to reaction with water can be used as a paint.
When applied as an adhesive or an orthopedic cast bandage, it cannot exhibit sufficient strength and cannot withstand use.

On the other hand, when the average number of hydroxyl groups per molecule of the polyol compound exceeds 2.0, the reaction between the obtained urethane prepolymer and water causes parts that form a network structure, and as the network structure increases, the number of hydroxyl groups gradually increases. It will increase in hardness.

In this way, when the average number of hydroxyl groups per molecule of polypropylene glycol exceeds 2.5, on the contrary, the network structure in the constituent molecules occupies a considerable number, and the length of the segment becomes short. If the material becomes too stiff, brittleness becomes noticeable as the hardness increases, making it unsuitable for use as paint, adhesive, orthopedic cast bandage, etc.

The urethane prepolymer composition of the present invention is prepared by adding 0.1 to 2.0 parts by weight of a curing catalyst and a storage stabilizer, respectively, to the urethane prepolymer as described above.

When the moisture-curable urethane prepolymer composition of the present invention is used particularly as an orthopedic cast bandage, the polyol compound and the diisocyanate compound are combined with a terminal -NCO
If the reaction is carried out so that the group content is in the range of 7 to 15%, a grade having appropriate strength and tenacity can be obtained.

When synthesizing a urethane prepolymer containing -NCO groups in the range of 7 to 15% by weight, if a polyol compound with a number average molecular weight of 400 or less is used, the viscosity of the urethane prepolymer increases too much, resulting in a network formation. This results in the disadvantage that it becomes difficult to impregnate.

Even if it were possible to impregnate this material, the cured product caused by the reaction with water would be too hard and brittle, so paints,
Not suitable for use with adhesives, orthopedic plaster bandages, etc.

On the other hand, when using a polyol compound with a number average molecular weight of 2,500 or more and a urethane prepolymer containing -NCO groups in the range of 7 to 15% by weight, the viscosity becomes too low, making it difficult to secure a coating amount. , a sufficient binder effect cannot be expected.

Even if glass fiber cloth or the like is impregnated as an orthopedic cast bandage, liquid will bleed during packaging, storage, and transportation, making it unusable.

Furthermore, the hardened product resulting from the reaction with water is not sufficiently hard and cannot serve the role of fixing the affected area as a cast bandage.

The effect of the formulation by adjusting the number of hydroxyl groups of the present invention is that by adjusting the number of functional groups, even if the prepolymer has the same -NCO group content (7 to 15% by weight in the present invention), (1) The viscosity can be adjusted to obtain a desired viscosity (2) The hardness and strength of the cured coating film can be adjusted.

Dimorpholinotriethyl ether, which is a curing catalyst used in the moisture-curable urethane prepolymer composition and moisture-curable medical fixative of the present invention, has the following chemical structure, and contains morpholine and triethylene glycol, for example. , can be produced by dehydration condensation reaction in the presence of a catalyst consisting of a Cu--Ni--Pt group element (see, for example, JP-A-62-149647).

Note that 2-morpholine can be produced by subjecting jetanolamine and sulfuric acid to a superheated reaction.

Add this curing catalyst to the urethane prepolymer at a rate of 0.1~
It is recommended to add 2 parts by weight.

The storage stability of the urethane prepolymer can be increased by adding an acid chloride compound as a storage stabilizer used in the present invention together with a catalyst.

Specific examples of acid chloride compounds include the following.

For example, isophthaloyl chloride, 2-ethylhexinoyl chloride, octanoyl chloride, chlorobenzoyl chloride, benzoyl chloride, steproyl chloride, sebacoyl chloride, decanoyl chloride, dodecanoyl chloride, nonanoyl chloride, balmitoyl chloride, 3-phenylpropenoyl chloride, n chloride -butanoyl, hexanoyl chloride, 2-methylpropanoyl chloride, 2,4-dichlorobenzoyl chloride, 2,6
- Diku0 benzoyl chloride, lauroyl chloride, methyl benzoyl chloride, etc.

It is possible to use one kind or a combination of two or more kinds of the above acid chloride compounds.

The amount of acid chloride compound added is 1 of urethane prepolymer.
If it is less than 0.1 part by weight per 00 parts by weight,
During the coating, packaging, etc. process, it reacts with a small amount of moisture in the air and loses its effect as a storage stabilizer, so it cannot exhibit its storage stability imparting effect.

Moreover, no effect was observed even when treatment was performed with sufficient attention paid to the moisture in the air.

On the other hand, if the amount of acid chloride compound added is more than 2.0 parts by weight, although the storage stabilizer has excellent effects, the rate of effect due to the reaction with water during use is too different, resulting in poor performance in paints, adhesives, etc. It has poor workability when used as an agent or orthopedic cast bandage, and it also generates a pungent odor unique to acid chloride compounds, which has a negative impact on work.

In addition, moisture-curable urethane prepolymer compositions generate carbon dioxide gas as they react with moisture and become polymerized, so when used in paints, adhesives, orthopedic cast bandages, etc., the resin may It may foam and cause a decrease in strength or cause a blemish on the appearance. As a method of suppressing foaming caused by the generation of carbon dioxide gas, a silicone-based antifoaming agent is added to the urethane prepolymer at a concentration of 0.01 to 1.0%.
It is satisfied by adding part by weight. This silicone antifoaming agent is not always used, but may be used depending on the case.

Next, a case will be described in which a moisture-curable urethane prepolymer composition containing a curing catalyst, a storage stabilizer, an antifoaming agent, etc. is used as an orthopedic cast bandage by the above-mentioned operation.

The urethane prepolymer composition after blending with the various additives mentioned above is impregnated into a cloth, net, etc. made of fibers such as glass, polyester, Kevlar, polyaramid, ceramic, boron, stainless wool, etc., and is removed from moisture in the air. Pack for protection.

Suitable packaging materials include aluminum and plastic laminate films.

When in use, tear a cloth or mesh impregnated with moisture-curable urethane prepolymer, tear the packaging, take it out, soak it in water, and immediately wrap it around the affected area to harden the urethane prepolymer composition and increase its strength. The affected area is fixed by leaving it as it is until it appears.

The amount of the urethane prepolymer composition impregnated into the base fabric such as cloth or net-like material is preferably in the range of 30 to 300% when the weight of the base fabric is 100%.

When it is less than 30, the binder effect on the base fabric is insufficient and the necessary strength cannot be maintained.

On the other hand, if it is more than 300, liquid may drip during impregnation, or a resin pool may form at the inner bottom of the packaging material during storage and transportation after packaging, which is not appropriate.

Furthermore, when immersed in water, it is difficult for water to penetrate into the interior, which lengthens the curing time, forcing patients to wait for a long time, and the desorption of carbon dioxide generated during curing becomes difficult, causing foaming. This is not desirable as it may cause

Also, material is wasted.

Specific embodiments of the moisture-curable urethane prepolymer composition and moisture-curable medical fixative of the present invention are as follows.

The moisture-curable urethane prepolymer composition according to claim (1), wherein the diisocyanate compound (a) is an aromatic diisocyanate compound.

(b) The moisture-curable urethane prepolymer composition according to claim 1, wherein the aromatic diisocyanate compound is 4,4' diphenylmethane diisocyanate and the polyol compound is polypropylene glycol.

(C) The polypropylene polyol has 2 or 3 hydroxyl groups in one molecule, the average number of hydroxyl groups per molecule is 2 or more and 2.5 or less, and the number average molecular weight is in the range of 400 to 2,500. (1) Moisture-curable urethane prepolymer composition as described in claim 1.

(d) A patented rethane prepolymer composition characterized in that it contains a storage stabilizer consisting of one or a combination of two or more acid chlorides.

[Example] The present invention will be described below with reference to Examples and Comparative Examples.

[Comparative Example-1] Weigh out 775 g of 4.4'-diphenylmethane diisocyanate into a three-neck seperate flask, and heat it to 50°C.

Next, 2700 g of polypropylene glycol having an average molecular weight of 2700 was weighed into a dropping funnel, and the entire amount of polypropylene glycol was dropped into the separable flask over 1 hour while stirring the flask.

At this time, the temperature was controlled so that the internal temperature of the flask was within the range of 50 to 80°C.

After dropping the entire amount of polypropylene glycol, the internal temperature of the flask was maintained at 75° C., and stirring was continued for 3 hours to synthesize a urethane prepolymer.

Next, 0.3 parts by weight of dimethylaminoethanol was added as a curing catalyst to 100 parts by weight of the urethane prepolymer.
0.5 part by weight of lauroyl chloride as a storage stabilizer was added, and further 0.1 part by weight of a silicone antifoaming agent was added, followed by thorough mixing and stirring.

This material was taken out into a 500 ml container and sealed tightly to complete the preparation of a moisture-curable urethane prepolymer composition.

[Example-1] Using the same apparatus as in Comparative Example-1, 775 g of 4,4'-diphenylmethane diisocyanate was prepared with an average molecular weight of 1700.
1700 g of polypropylene glycol was weighed out and a urethane prepolymer was synthesized in the same manner as in Comparative Example-1.

Next, 0 parts of dimorpholinotriethyl ether was added as a curing catalyst to 100 parts by weight of the above urethane prepolymer.
．． 3 parts by weight, 0.5 parts by weight of lauroyl chloride as a storage stabilizer
0.1 parts by weight of a silicone antifoaming agent were added, thoroughly mixed, and the mixture was placed in a 500 ml container and sealed.

[Example-2] Using the same apparatus as in Comparative Example-1, 1550 g of 4,4°-diphenylmethane diisocyanate, average molecular weight 700
1400 g of polypropylene glycol was weighed out and a urethane prepolymer composition was prepared in the same manner as in Comparative Example-1.

Next, 0.3 parts of dimorpholino triethyl ether was added as a curing catalyst to 100 parts by weight of the urethane prepolymer.
0.5 parts by weight of lauroyl chloride as a storage stabilizer and 0.1 parts by weight of a silicone antifoaming agent were added, and after thorough mixing and stirring, the mixture was placed in a 500 ml container and sealed tightly.

[Example-3] Using the same apparatus as in Comparative Example-1, 1550 g of 4,4'-diphenylmethane diisocyanate and an average molecular weight of 400
8°Og of polypropylene glycol was weighed out, and a urethane prepolymer was synthesized in the same manner as in Comparative Example-1.

Next, to 100 parts by weight of the urethane prepolymer, 0.8 parts by weight of dimorpholinotriethyl ether as a curing catalyst, 0.5 parts by weight of lauroyl chloride as a storage stabilizer, and 0.1 part by weight of a silicone antifoaming agent were added. After thoroughly mixing and stirring, divide into a 500-all container and seal tightly.

[Comparative Example-2] Using the same apparatus as in Comparative Example-1, 1550 g of 4.4'-diphenylmethane diisocyanate, average molecular weight 300
6°Og of polypropylene glycol was weighed out and a urethane prepolymer was synthesized in the same manner as in Comparative Example-1.

Next, to 100 parts by weight of the urethane prepolymer, 0.8 parts by weight of dimethylaminoethanol as a curing catalyst, 0.5 parts by weight of lauroyl chloride, and 0 parts by weight of a silicone antifoaming agent were added.
．． After adding 1 part by weight and stirring thoroughly, 500 mr
Aliquot it into a container and seal it tightly.

The five samples of Examples 1 and 2.3 and Comparative Example 1.2 described above were subjected to the following operations and evaluated as orthopedic cast bandages.

〔Evaluation methods〕

B-A useful tape made of glass fiber with a commercial density of 0.035 g/-, a mesh number of 90 numerical apertures/in2, and a fabric width of 7°5C11 is impregnated with moisture-curable urethane prepoly 7- using a coater head of two rollers. Then, create an impregnated tape with a length of 4 m, wrap the tape around a plastic cylinder with a diameter of 10 cI+ in 5 layers, immerse it in water for 30 seconds, leave it in the air for 1 hour, and immediately pull out the plastic cylinder. A pressure load was applied in the diametrical direction of the layered tape, and its pressure resistance and breaking strain were measured.

Here, the necessary conditions for an orthopedic cast bandage are that it has both a pressure resistance of 10 kf or more and a fracture strain of 20% or more.

[Example-4] Using the same apparatus as in Comparative Example-1, 490 g of polypropylene glycol with an average molecular weight of 700 and 490 g of polypropylene glycol with an average molecular weight of 100 were added to 885 g of 4,4°-diphenylmethane diisocyanate.
A urethane prepolymer was synthesized from a mixture of 300 g of polypropylene triol of No. 0 in the same manner as in Comparative Example-1.

Next, for 100 parts by weight of the above urethane prepolymer,
0.0% dimorpholinotriethyl ether as a curing catalyst.
3 parts by weight, 0.5 parts by weight of lauroyl chloride as a storage stabilizer, and 0.1 part by weight of a silicone antifoaming agent were added, and after thorough mixing, the mixture was dispensed into a 500 ml container.

[Example-5] Using the same apparatus as in Comparative Example-1, 960 g of 4,4°-diphenylmethane diisocyanate, 350 g of polypropylene glycol with an average molecular weight of 700, and 350 g of polypropylene glycol with an average molecular weight of 100 were added.
A urethane prepolymer was synthesized from a mixture of 350 g of polypropylene triol of No. 0 in the same manner as in Comparative Example-1.

Next, for 100 parts by weight of the above urethane prepolymer,
0.0% dimorpholinotriethyl ether as a curing catalyst.
Add 3 parts by weight of lauroyl chloride, 0.5 parts by weight of lauroyl chloride, and 0.1 part by weight of silicone antifoaming agent, stir thoroughly and mix.
Aliquoted into 0 ml containers.

[Comparative Example-3] Using the same apparatus as in Comparative Example-1, 1030 g of 4,4'-diphenylmethane diisocyanate was mixed with an average molecular weight of 700.
210g of polypropylene glycol and average molecular weight 10
A urethane prepolymer was synthesized from a mixture of 700 g of polypropylene triol No. 00 in the same manner as in Comparative Example-1.

Next, for 100 parts by weight of the above urethane prepolymer,
0.3 parts by weight of dimethylaminoethanol, 0.5 parts by weight of lauroyl chloride, and 0.1 parts by weight of a silicone antifoaming agent were added, thoroughly stirred and mixed, and then fractionated into a 500 ml container.

These Examples-4, -5 and Comparative Example-3 were evaluated as orthopedic cast bandages according to the above-mentioned evaluation method, and the results are shown below.The results of the previous Example-2 are also referred to. Listed for.

[Measurement results] Here, moisture-curable urethane prepolymer weight + fabric weight pressure load capacity (kg) = load at yield point = λ outside resin coating pressure load capacity at break (%) (kr) (%) Example-480
2542 Example-5852725 Example-2752250 Comparative Example-3105339 Next, examples will be described in which various combinations of 3-iron amine and acid chloride are used in the same prepolymer.

[Synthesis of prepolymer]

3100 g of 4,4'-diphenylmethane diisocyanate was weighed into a 3-meter separable flask, and the temperature was raised to 50°C.

Next, polypropylene glycol 2 with an average molecular weight of 700
800 g was weighed into a dropping funnel, set in a separable flask, and the entire amount of polypropylene glycol was added dropwise over 1 hour while stirring the flask.

At this time, the temperature was controlled so that the internal temperature of the flask was within the range of 50 to 80°C.

After dropping the entire amount of polypropylene glycol, the internal temperature of the flask was maintained at 75° C., and stirring was continued for 3 hours to synthesize a urethane prepolymer.

0.1 parts by weight of silicone antifoaming agent was added to the entire synthesized urethane prepolymer, and the mixture was further stirred for 30 minutes.
The sample was separated and sealed in a 500 ml container.

This product will be referred to as prepolymer A hereinafter.

A tertiary amine and acid chloride were added to prepolymer A separated by the above method, and the pressure resistance and breaking strain were measured according to the evaluation method described above, and the curing time and storage stability acceleration test were also conducted. It was measured.

Here, the curing time refers to a fabric tape made of E-glass fiber impregnated with a moisture-curable urethane prepolymer, immersed in water for 30 seconds, left in the air at room temperature, and the fabric surface is rubbed with a finger. It refers to the time it takes for the tack to disappear when touched, preferably 5 minutes or more and 20 minutes or less.

Further, an accelerated storage stability test was conducted as follows. Weigh out 50 g of moisture-curable urethane prepolymer into a 100 ml polypropylene container and seal the container.

This product was left standing in an atmosphere of 130°C, and the fluidity of the prepolymer in the container was observed every 100 minutes.

The end point is the time when the fluidity of the prepolymer in the container is no longer observed even when the container is tilted, and the time elapsed at that point is recorded.

The longer the time to this end point, the better the storage stability of the prepolymer.

(Effects of the Invention) As described above, according to the present invention, it is possible to obtain a moisture-curable urethane prepolymer composition that has excellent storage stability and can appropriately adjust the curing time during use, and It exhibits excellent performance in the fields of adhesives, orthopedic casts, etc.

Procedural amendment (voluntary)

Claims (2)

[Claims] (1) It is characterized by containing a urethane prepolymer having a -NCO group at the end consisting of a diisocyanate compound and a polyol compound and dimorpholinotriethyl ether having the following chemical structure ▲Mathical formula, chemical formula, table, etc. ▼ as a curing catalyst. Moisture-curable urethane prepolymer composition. (2) A resin composition containing a urethane prepolymer having a -NCO group at the terminal consisting of a diisocyanate compound and a polyol compound and dimorpholinotriethyl ether having the following chemical structure ▲Mathical formula, chemical formula, table, etc.▼ as a curing catalyst. A moisture-curable medical fixing material, characterized in that it is supported on a net-like support.