JPH069746A - Composition - Google Patents

Abstract

PURPOSE:To obtain a polyisocyanate compound composition not causing the corrosion of the equipment and the worsening of the working environment by mixing a polyisocyanate compound with an alkylene carbonate and optional assistants. CONSTITUTION:The composition comprises a polyisocyanate compound, an alkylene carbonate and optional assistants. The amount of the polyisocyanate compound is desirably 50-95wt.% based on the total composition. Examples of the polyisocyanate compounds include 4,4'-diphenylmethane diisocyanate, toluene diisocyanate, urethane-modified isocyanates and allophanate-modified isocyanates. Desirable examples of the alkylene carbonates include ethylene carbonate and propylene carbonate. The amount of this compound is desirably 5-50wt.% based on the total composition.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a composition containing a polyisocyanate compound.

[0002]

2. Description of the Related Art Conventionally, a difunctional isocyanate compound represented by 4,4'-diphenylmethane diisocyanate (MDI) or toluene diisocyanate (TDI), or a urethane-modified isocyanate called a prepolymer which is polyfunctional by modifying these compounds. Polyisocyanate compounds such as allophanate-modified isocyanates and biuret-modified isocyanate compounds, or compositions mainly containing these are used as curing agents, adhesives, raw materials for polyurethanes, and the like.

When these are used as curing agents,
By impregnating the composition into a material that can be impregnated, such as a soft foam, and compressing the soft foam or the like to shape it, and reacting the polyisocyanate compound in the composition with water or the like. It cures and fixes the compressed shape. When it is used as an adhesive, it utilizes the self-adhesiveness exhibited when the composition is cured.

However, since this compound, particularly the polyisocyanate compound used as a prepolymer, has a high viscosity,
When impregnating these into the soft foam or the like,
Dilution is performed with a halogenated hydrocarbon such as 1,1-trichloroethane. Most of the halogenated hydrocarbons are volatile, and most of them are volatilized by the heat of compression molding during the curing. However, a part of it is decomposed by heat to generate halogen gas.

For example, since 1,1,1-trichloroethane contains chlorine, it decomposes by heating or the like to generate chlorine gas. The chlorine gas may corrode the equipment or short circuit the electric wiring due to the corrosion. Also, due to the chlorine gas, or 1,1,
There is also a problem that the working environment is deteriorated due to the pungent odor peculiar to 1-trichloroethane.

[0006]

Therefore, the present invention has been made in view of the above points, and provides a composition containing a polyisocyanate compound which does not cause corrosion of equipment and does not deteriorate the working environment. It is a thing.

[0007]

The present invention relates to a composition comprising a polyisocyanate compound, an alkylene carbonate, and an auxiliary agent which is optionally added.

[0008]

The polyisocyanate compound used in the present invention is 4,4'-diphenylmethane diisocyanate (MDI) or toluene diisocyanate (TD).
A bifunctional isocyanate compound typified by I) or a urethane-modified isocyanate, an allophanate-modified isocyanate, a biuret-modified isocyanate compound, which are so-called polypolymers obtained by modifying these, are used alone or as a mixture.

The amount of the polyisocyanate compound is preferably in the range of 50 to 95% by weight based on the total amount of the composition, and is preferably determined according to the polyisocyanate compound to be used, the alkylene carbonate or the use of the composition. This is because when the amount is less than the above range, the original action of the polyisocyanate compound becomes low, and when the amount is more than the above range, the action of the alkylene carbonate becomes low.

As the alkylene carbonate used in the present invention, those having 2 to 4 carbon atoms may be used alone or in combination. Among them, ethylene carbonate or propylene carbonate is preferably used alone or as a mixture. Since these alkylene carbonates do not have an irritating odor and do not contain harmful chlorine, they do not corrode equipment or deteriorate the environment.

The alkylene carbonate has a function of diluting the polyisocyanate compound without directly reacting with the polyisocyanate compound, so that the composition of the present invention can have a desired viscosity. Therefore, when the composition of the present invention is used by being impregnated into a soft foam or the like, the amount of alkylene carbonate can be adjusted to facilitate impregnation of the composition into the soft foam or the like. On the other hand, when the composition of the present invention is used as a polyurethane raw material, the viscosity on the polyisocyanate side, which is usually higher than the viscosity on the polyol side, can be lowered according to the viscosity on the polyol side. Therefore, the stirring can be improved and the reaction between the polyol and the polyisocyanate compound can be efficiently performed.

Further, the alkylene carbonate is hydrolyzed in the presence of water to produce a dihydric alcohol such as ethylene glycol as shown in the following formula.

[Chemical 1]

By the way, the dihydric alcohol has the action of reacting with the polyisocyanate compound to extend the chain of the polyurethane resin, and has been widely used as a chain extender (also referred to as a cross-linking agent) of the polyurethane resin. Is.

Therefore, by impregnating the composition of the present invention into an impregnable molding material such as polyurethane foam,
When the polyisocyanate compound in the composition is cured by water, the dihydric alcohol generated by the hydrolysis reacts with the excess polyisocyanate compound in the composition to form a polyurethane resin in the molding material. To do. Therefore, the molding material can be reinforced and modified. Further, when the composition of the present invention is used as a polyurethane raw material together with water, the dihydric alcohol generated by the hydrolysis can be used as a chain extender for the polyurethane resin.

The amount of alkylene carbonate is preferably in the range of 5 to 50% by weight based on the total amount of the composition, and is preferably determined according to the use of the alkylene carbonate, polyisocyanate compound or composition used. If less than the above range, the action of alkylene carbonate becomes low,
On the contrary, when the amount is larger than the above range, the original action of the polyisocyanate compound is lowered.

Further, in the present invention, as an auxiliary agent added as required, there are amine-based or metal-based catalysts, silicon-based foam stabilizers, flame retardants and the like. These auxiliaries are appropriately added in appropriate amounts according to the use of the composition according to the present invention.

[0017]

EXAMPLES Examples 1 to 7 of the present invention will be described below. The polyisocyanate compound used was 4,4 ′.
-Diphenylmethane diisocyanate (MDI) and toluene diisocyanate (TDI). The alkylene carbonate used is propylene carbonate and ethylene carbonate.

As an auxiliary agent, a catalyst, a silicone foam stabilizer,
A flame retardant was used. The catalyst used was triethylenediamine,
The silicone foam stabilizer is L-520 (manufactured by Nippon Unica), and the flame retardant is a phosphorus compound.

The above polyisocyanate compound, alkylene carbonate and auxiliary agent were mixed in the blending ratio (% by weight) shown in the following table to prepare the compositions of Examples 1 to 7.

The compositions of the above examples can be used in various applications. As an example of its application, an example used for molding a panel molded product is shown below.

First, a soft urethane foam is impregnated with the composition of Example 1 obtained above to form an impregnated foam. At that time, the polyisocyanate compound (M
Since DI) is diluted with alkylene carbonate (propylene carbonate) so that the entire composition has an appropriate viscosity, the composition easily impregnates a flexible urethane foam.

Then, water is sprayed on the surface of the impregnated foam, and then a surface material and a back surface material are laminated on the impregnated foam. The water content appropriately contains a catalyst.

Thereafter, the laminated body made of the soft urethane foam or the like is sandwiched between the mold surfaces of the heating press mold heated to about 120 ° C. to form the mold surface shape, and the sprayed water is sprayed onto the mold surface of the heating mold. The retained heat produces steam, and the steam causes the polyisocyanate compound in the composition to react and cure. Then, by curing the polyisocyanate compound, the laminate is fixed in a compressed shape, and each member of the laminate is bonded and integrated by the adhesiveness of the polyisocyanate compound at the time of curing to obtain a desired panel molded article.

During molding of the panel molded article, in the composition of the present invention, the alkylene carbonate reacts with water vapor to hydrolyze to produce a dihydric alcohol. However, since alkylene carbonate does not contain chlorine, chlorine gas is not generated, and there is no fear of facility corrosion or environmental deterioration. Further, the dihydric alcohol produced by the hydrolysis reacts with the excess polyisocyanate compound in the composition to form a polyurethane resin in the impregnated foam,
Reinforces and reforms panel molded products.

[0025]

As described above, the composition of the present invention comprises the polyisocyanate compound, the alkylene carbonate, and
Since it comprises an auxiliary agent which is added as necessary, it can be used not only as an impregnating and curing agent but also for various purposes. Moreover, even if the alkylene carbonate is decomposed, halogen gas such as chlorine gas is not generated, and there is no risk of corrosion of equipment and deterioration of working environment. Further, since the composition of the present invention has no irritating odor, it does not make the operator feel uncomfortable. Furthermore, the composition of the present invention has an advantage that it can be used as a chain extender for a polyurethane resin because it hydrolyzes to generate a dihydric alcohol when used together with water.

Claims (1)

[Claims] 1. A composition comprising a polyisocyanate compound, an alkylene carbonate, and an auxiliary agent added if necessary.