JPS62115019A - Production of polyurethane - Google Patents

Abstract

PURPOSE:To obtain a polyurethane excellent in solvent resistance and hydrolysis resistance, by reacting a specified polyol component with a diisocyanate compound and a chain extender component. CONSTITUTION:1mol of a polyol compound (A) such as a polyester polyol of MW of 500-4,000, which is a mixed polyol comprising 0.6X0.8mol of a polyester (a) formed by using succinic acid as an acid component (e.g., succinic acid/ diethylene glycol) and 0.4-0.2mol of 3-methylpentanediol (b) is reacted with 1-5mol of a diisocyanate (B) (e.g., 4,4'-diphenylmethane diisocyanate) at 50-100 deg.C for 3-12hr to obtain an isocyanate group-terminated prepolymer. This prepolymer is diluted with an organic solvent (e.g., dimethylformamide) and 0-4mol of a chain extender component (e.g., dimethylformamide) and 0-4mol of a chain extender component (e.g., 1,4-butanediol) is added to this solution to conduct reaction at 40-100 deg.C for 2-50hr.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Application of the Invention) The present invention is directed to polyurethane. ! Regarding the manufacturing method, it relates to a method for manufacturing polyurethane that has excellent solvent resistance and hydrolysis resistance.

(Prior Art) Conventionally, as a method for producing polyurethane, it has been widely practiced to react a polyol component, a diisocyanate compound, and a chain extension component.

Polyurethane is used as a base material for synthetic leather, a surface treatment agent, a fiber base material, etc. because the formed film or fiber has excellent properties such as flexibility, elasticity, and strength.

However, especially in order to be used as a synthetic leather material for clothing or as a surface treatment agent, polyurethane is required to have excellent dry cleaning resistance and washing resistance. However, it has not yet been developed and its development is desired.

(Problems to be Solved by the Invention) An object of the present invention is to provide a method for producing polyurethane having excellent solvent resistance and hydrolysis resistance.

(Means for Solving the Problem) As a result of research to achieve the above object, the present inventor succeeded by using a specific type of polyol in a specific ratio as a polyol component, and completed the present invention.

To summarize the present invention, in producing polyurethane by reacting a polyol component, a diisocyanate compound, and a chain extension component, (1) a polyester having succinic acid as an essential acid component;
- A method for producing polyurethane characterized by using a mixed polyol consisting of methylpentanediol.

To explain the present invention in more detail, as the polyol component used in the present invention, a polyester using succinic acid as an acid component and 3-methylpentanediol are used together.

The mixing ratio of these two components is 0.4 to 0.8 mol of the former polyester and 0.4 to 0.2 mol of the latter diol per 1 mol of the polyol component.

This is because polyester that uses succinic acid as the acid component has 0
．． When the amount exceeds 8 mol, hydrolysis resistance deteriorates,
On the other hand, if the amount is less than 0.6 mol, sufficient solvent resistance cannot be obtained.

Diincyanate compounds used in the present invention include aliphatic diisocyanates such as hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, 2,6-lysine diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,4- and 2,6 - Aromatic diisocyanates such as lylene diisocyanate, isophorone diisocyanate, alicyclic diisocyanates such as hydrogenated compounds of aromatic diisocyanates, and the like can be used.

Diol components used for chain extension include ethylene glycol, propylene glycol, trimethylene glycol, 1,4-butanediol, 1°5-bentanediol, 1,6-hexanediol, cyclopentane-1,
2-diol, cyclohexane-1,4 diol, etc. are suitable.

On the other hand, diamines used in combination with the above diol or used alone include aliphatic diamines such as ethylene diamine, hexamethylene diamine, trimethylhexamethylene diamine, isophorone diamine, piperazine, aminoethyl piperazine, 2,5-dimethyl piperazine, 3
,9-bis-(3-aminopropyl)-2,4,8,1
Alicyclic and heterocyclic diamines such as 0-tetraxaspiro[5,5]undecane, Zarani, m-phenylenediamine, p-phenylenediamine, 2,4-tolylenediamine, m-xylylenediamine, p -Aromatic diamines such as xylylene diamine and 4,4-diaminodiphenylmethane are used.

The organic solvent used in the production of polyurethane may be any combination of those conventionally generally used as a dissolving agent for polyurethane, such as dimethylformamide, diethylformamide, dimethylacetamide, acetone, methyl ethyl ketone, and dimethyl sulfoxide. You can use them selectively. The number average molecular weight of polyurethane is adjusted by the number average molecular weight of the polyol component and the molar amount of the chain extender used in polyurethane production.

An example of the polyurethane used in the present invention is that 1 mol of a specific polyester polyol having a molecular weight of 500 to 4000 is reacted with 1 mol to 5 mol of a diisocyanate component at 50 to 100'C for 3 to 12 hours. A urethane prepolymer having a terminal isocyanate group is diluted with an organic solvent and then reacted with 0 to 4 moles of a chain extender at 40 to 100'C for 2 to 50 hours.

The polyurethane obtained in the present invention can be used as a base material or coating agent for woven fabrics, non-woven fabrics, synthetic leather, artificial leather, paper, wall covering materials, synthetic resin sheets, etc., and particularly as a base material or coating agent for clothing. suitable.

(Examples) Examples will be shown below to more specifically explain the present invention. However, the present invention is not limited to the scope of these examples. All parts in the examples are by weight unless otherwise specified.

Example 1 Volume 13 with reflux condenser and stirrer. l! 320 parts of polyester (succinic acid-diethylene glycol) with an average molecular weight of 2000, 80 parts of 3-methylpentanediol, and 150 parts of 4.4'-difnyelmethane diisocyanate were added to a four-round flask, and 1 part of dibutyltin acetate was added as a catalyst. did. This product was subjected to a reaction at 80'C for 3 hours under nitrogen gas. Next, 1231 parts of dimethylformamide, 252 parts of methylbutyleth
Add the fu part and 36 parts of 1,4-butanediol to 70°C.
The reaction was carried out for 4 hours to prepare polyurethane.

Examples 2 to 4 and Comparative Examples 1 to 4 Polyurethanes were prepared in the same manner as in Example 1 except that the type of polyester and the ratio used were changed to those shown in Table 1.

However, film performance was measured by the method shown below.

Solvent resistance: A film (film thickness: 60 μm, 4 cm x 4 cm) was left in a solvent at 50° C. for 30 minutes and then taken out, and the percentage of surface area before and after immersion was measured.

Hydrolysis resistance: The film was immersed in a 5% potassium hydroxide aqueous solution at 100℃ for 15 minutes, and the rating was N based on the change in appearance.

It was displayed in

(Effects of the Invention) As is clear from the above explanation, the polyurethane obtained by the present invention has excellent solvent resistance and hydrolysis resistance.

Claims (1)

[Claims] 1. In producing polyurethane by reacting a polyol component, a diisocyanate compound, and a chain extension component,
As a polyol component, (1) 0.6 to 0.8 mol% of a polyester having succinic acid as an essential acid component and (2
) A method for producing polyurethane, which comprises using a mixed polyol containing 0.4 to 0.2 mol% of 3-methylpentanediol.