JP2754217B2 - Stabilized polyurethane composition - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to stabilized polyurethane compositions, and in particular to polyurethane compositions stabilized against yellowing and degradation by light.

Polyurethanes obtained from polyisocyanates and polyhydroxy polymers having a relatively low degree of polymerization and functional active hydrogen-containing compounds have excellent mechanical properties with elasticity, and can be used for fibers, films, foams, adhesives, It is used for a wide range of valuable applications, such as paints and resins.Among them, polyurethanes based on aromatic isocyanates such as diphenylmethane diisocyanate exhibit high rubber elasticity, excellent tensile stress, excellent recoverability, and This is particularly important because it has excellent properties in heat resistance behavior.

According to the present invention, the durability and whiteness retention characteristics of the elastic function of these materials can be enhanced, and their performance can be maintained. As a result, commercial value can be significantly improved.

[Conventional technology]

Polyurethane is unstable to light, and is liable to yellow and deteriorate when exposed to light. For this reason, various antioxidants, ultraviolet absorbers and anti-tarnish agents have been proposed,
Attempts to improve performance have been made, but have not yet reached a satisfactory level. As a stabilizer, for example, a hindered phenol compound having an increased molecular weight (JP-A-61-4761)
No. 819, JP-A-62-96560). It is also widely known that a combination of a hindered phenol compound and a benzotriazole compound (JP-B-60-21187, JP-A-56-11948) exhibits an excellent synergistic effect.

In addition, a benzophenone compound is also known as a typical ultraviolet absorber, but when used for polyurethane having extremely low durability against light, the effect is inferior to that of a benzotriazole compound, The benzophenone compounds are rarely, if ever, used industrially in fiber or film-like polyurethane. Conventionally known low molecular weight benzophenone compounds, for example, 2,
Since 2'-dihydroxy-5,5'-dimethoxybenzophenone is extremely sublimable, when producing a fiber from a polyurethane composition containing the same, the fiber is scattered in a spinning cylinder during dry spinning, or the resulting fiber It was found that it had disadvantages such as easy falling off during dry cleaning.

As a benzophenone compound which is relatively effective in stabilizing polyurethane, 2,2'-dihydroxy-4,4'-
There are dimethoxybenzophenone (manufactured by BASF, trade name Ubinal D-49) and 2,2 ', 4,4'-tetrahydroxybenzophenone (manufactured by BASF, trade name Ubinal D-50). Therefore, it cannot be used for polyurethane fibers for which whiteness is an important commercial element, because even a small amount of addition gives a significant change in hue.

Further, U.S. Patent No. 3,313,866, U.S. Patent No. 3,365,421
The specification describes that the benzophenone compound is effective for polyvinyl halide, but when the compound was used alone in polyurethane, it was unable to exhibit a sufficient stabilizing effect.

[Problems to be solved by the invention]

Based on the above current situation, the present inventors can prevent coloring and deterioration of physical properties even when exposed to light or heat for a long period of time, and have no scattering due to evaporation or the like during the manufacturing process of the product, thus preventing the product from being used. Intensive research was conducted to find a polyurethane stabilizer that does not fall off during washing or the like.

[Means for solving the problem]

As a result, conventionally, as a stabilizer for polyurethane,
Benzophenone compounds, which were considered to have low performance, show only a lower stabilizing effect than benzotriazole compounds at low molecular weights, but high molecular weight compounds have superior effects to benzotriazole compounds. Was found to be unexpected. When a high-molecular-weight benzophenone compound represented by the following formula (1) is used in combination with a hindered phenol compound having a certain molecular weight range, a significantly excellent stabilizing effect can be imparted to the polyurethane, and at the same time, a conventionally known method is used. It was also found that the above-mentioned drawbacks of the benzophenone compound, such as being easily lost, were eliminated.

That is, in the present invention, the polyurethane has (A) a number average molecular weight comprising a repeating unit represented by the following general formula (1).
The present invention relates to a polyurethane composition comprising a stabilizing amount of a benzophenone compound having a range of 1,000 to 100,000 and a hindered phenol compound having a number average molecular weight of 600 to 10,000 (B).

(However, R ₁ is a hydrogen atom or a methyl group, R ₂ and R ₃ are a hydrogen atom or a methyl group, and at least one of R ₂ and R ₃ is a hydrogen atom, and R ₄ is a hydrogen atom or a carbon atom. And an alkyl group of Formulas 1 to 4).

Further, in addition to the components (A) and (B) of the present invention, (C)
It has been found that a tertiary nitrogen-containing polymer used as a component can impart more excellent light embrittlement resistance and light coloring resistance.

The number average molecular weight of the benzophenone compound represented by the general formula (1) used in the present invention must be in the range of 1,000 to 100,000, and more preferably in the range of 10,000 to 80,000. The number average molecular weight of the hindered phenol compound must be in the range of 600 to 10,000, and more preferably in the range of 700 to 4,000. When the number-average molecular weight is lower than the lower limit, the polyurethane composition containing these is liable to be scattered by heat at the time of processing or to fall off at the time of using the processed product. If the number average molecular weight is higher than the upper limit, the compatibility with the polyurethane decreases, and the stabilizing effect also decreases.

The number average molecular weight referred to in the present invention is determined by GPC (manufactured by Waters) in terms of standard polystyrene.

Next, as preferred specific examples of the benzophenone compound (A) of the present invention represented by the general formula (1), (R ₁ , R ₂ , R ₃ , R ₄ ) in the formula (1) will be specifically shown. Compound, A-1 to A-
6 can be mentioned.

A-1: (H, H , H, H), A-2: (H, H, H, t-C 4 H 9), A-3: (CH 3, H, H, H), A- _{4: (H, CH 3,} H, H), A-5: (CH 3, CH 3, H, H), A-6: (H, H, CH 3, H), also hindered phenol compounds Specific examples of (B) include the following B-1 to B-5.

B-1: 1,3,5-Tris (4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanuric acid (n
= 700) (manufactured by American Cyanamid Co., Ltd., product name: Cyanox 1790), B-2: 3,9-bis [1,1-dimethyl-2-Δβ- (3-
t-butyl-4-hydroxy-5-methylphenyl)
Propionyloxydiethyl] -2,4,8,10-tetraoxaspiro [5,5] undecane (n = 741) (trade name MARK AO-80, manufactured by Adeka Argus Chemical Co., Ltd.), B-3: A polymer obtained by adding isobutylene to an addition polymer of dicyclopentadiene and p-cresol (n = 20)
00) (synthesized with reference to JP-A-61-47819), B-4: an addition polymer of p-cresol and divinylbenzene (n = 2800) (see JP-B-47-6510). B-5: an addition polymer of p-chloromethylstyrene and p-cresol (n = 2700) (synthesized with reference to JP-A-62-96560).

Specific examples of the tertiary nitrogen-containing polymer (C) include a diol component (the former) and a diisocyanate component (the latter) which are synthesized by a reaction at a molar ratio of 1.10.
-1 to C-4.

C-1: Nt-butyl-N, N-diethanolamine and 4,
4'-methylenedicyclohexyl diisocyanate (molar ratio 1.10), C-2: N-ethyl-N, N-diisopropanolamine
4,4'-methylenedicyclohexyl diisocyanate (molar ratio 1.10), C-3: Nt-amyl-N, N-diethanolamine and isophorone diisocyanate (molar ratio 1.10), C-4: Nt-amyl-N, N-diisopropanolamine and 4,4'-methylenedicyclohexyl diisocyanate (molar ratio 1.10).

In the present invention, the compounding amount of the components (A), (B) and (C) to the polyurethane is such that the amount of the component (A) relative to the polyurethane is 0.1%.
1 to 3% by weight, and the components (A), (B),
The total content of (C) is 0.3 to 1 with respect to polyurethane.
0% by weight, preferably 1.0 to 7% by weight. If the total amount is less than 0.3% by weight, the effect is insufficient.
If the total exceeds 10% by weight, the mechanical properties of the polyurethane molded article are adversely affected.

The composition of the present invention may also contain other known stabilizers, for example,
Benzotriazole UV absorbers, hindered amine light stabilizers, phosphite antioxidants (eg, Johoku Chemical Co., Ltd., JPH-3800, Adeka Argus Chemical Co., Ltd.)
MARK PEP-8, etc.), heavy metal deactivator (for example, Ciba Geigy, IRGANOX MD1024, Adeka Argus Chemical Co., Ltd., MARK CDA-1 or MARK)
Further effects can be expected when CDA-6, etc.) are used in combination.

Examples of known stabilizers include the following compounds. Benzotrizole UV absorbers, for example, 2-
(2'-hydroxy-5'-methyl-phenyl) benzotriazole, 2- (2'-hydroxy-5'-t-butyl-phenyl) benzotriazole, 2- (2'-hydroxy-3 ', 5'- Di-tert-butylphenyl) benzotriazole, 2- (2'-hydroxy-3'-tert-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3 ', 5 '-Di-t
-Butyl-phenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3 ', 5'-di-isoamyl-phenyl) benzotriazole, 2- [2-hydroxy-3,5- (1,1 -Dimethyl-1-phenylmethyl) phenyl] benzotriazole, 2- [2-hydroxy-
5- (1,1,3,3-tetramethylbutyl) phenyl] benzotriazole, methyl-3- [3-t-butyl-5-
(2H-benzotriazol-2-yl) -4-hydroxyphenyl] propionate and polyethylene glycol.

The following known examples can be given as hindered amine light stabilizers.

4-oxo-2,2,6,6-tetramethylpiperidine, 1,
3,8-triaza-2,4-dioxo-3-stearyl-7,7,
9,9-tetramethyl-spiro [4,5] decane, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate , Bis (2,2,6,6-tetramethyl-4-piperidyl)
Hexamethylene-1,6-dicarbamate, 1,3,8-triaza-2-oxo-3-phenyl-4-imino-7,7,9,9
-Tetramethyl-spiro [4,5] decane, 1,3,8-triaza-2,4-dioxo-3-n-octyl-7,7,9,9-tetramethyl-8-benzyl-spiro [4 , 5] Decane, Sanol LS-944 (Sankyo Pharmaceutical Co., Ltd., trade name), Chimassorb 1
19FL (manufactured by Ciba Geigy), trade name).

The compounding into the polyurethane can be carried out by adding it at any stage of the production of the polyurethane, but it is preferable to mix it after the completion of the polyurethane polymerization.

The solution or molten polyurethane composition thus obtained can be dried, wet or melt spun to obtain fibers. In particular, fibers obtained by dry spinning had excellent performance. Also, by performing various moldings, films and resin molded products can be obtained. In the case of foams, adhesives and paints, they can be added at an appropriate time during the manufacturing process or to the final product.

〔Example〕

 Next, examples will be described.

First, a method for producing a polymer and a fiber used in the examples, a treatment method performed before the evaluation of physical properties, items of the evaluation physical properties, a measuring method thereof, and the like are described.

Synthesis of Polyurethane Polymer 1000 parts by weight of polytetramethylene ether glycol having an average molecular weight of 1600 and 250 parts by weight of 4,4′-diphenylmethane diisocyanate are reacted while stirring at 80 ° C. for 2 hours in a stream of nitrogen gas to form an isocyanate group. A prepolymer having both ends was obtained. To this dimethylacetamide 1800
A part by weight was added and dissolved to obtain a homogeneous solution. Separately, 24.4 parts by weight of ethynylenediamine and 2.2 parts by weight of diethylamine are dissolved in 1100 parts by weight of dimethylacetamide, and the above intermediate polymer solution is added thereto at room temperature. A high viscosity solution of Poise was obtained. This is called dope A.

Production of Polyurethane Fiber To the dope A, the stabilizer shown in the example was added, and the mixture was stirred so as to be uniform. Then, the solution was vacuum degassed to remove air bubbles in the solution. The mixture was discharged from a spinneret having individual pieces into an atmosphere of about 200 ° C., spinning, drying, calcining, and oiling were performed, and the resultant was wound up at a winding speed of 500 m / min to obtain a 40-denier multifilament yarn.

Treatment of fiber The 40 denier yarn obtained by dry spinning was subjected to the following two treatments, treatment A and treatment B.

Treatment A: This is a washing treatment, in which 40 denier polyurethane fibers are immersed in boiling water under 50% elongation for 1 hour, and then a detergent (trade name, New Beads) dissolved at a concentration of 1.3 g / is used. After washing at 40 ° C for 40 minutes,
Dry at ℃ for 15 minutes.

Treatment B: This treatment combines dyeing and commercial dry cleaning.
Soak in boiling dye bath for 1 hour under% elongation. The composition of the dye bath is
As a dye, 1.2% owf of Blancophor CL (trade name) and 0.5 g / ammonium acetate were added to make the pH at room temperature 4.0.
And acetic acid in required amounts.

Then immerse in a stream of tap water and wash for 20 minutes, at 40 ° C
Dry for 30 minutes. Then, 25 ℃ in perchlor ethylene
And dried at 30 ° C. for 30 minutes.

Evaluation of light embrittlement resistance The test for light embrittlement resistance was performed by treatment methods A and B.
The denier fiber is stuck on white cardboard without stretching, and light is irradiated with a fade meter (FAL-3 type, manufactured by Suga Test Instruments Co., Ltd.). The tensile strength of the irradiated sample is measured at a strain rate of 1000% / min using a tensile tester (UTM-3, manufactured by Toyo Baldwin Co., Ltd.).

The degree of light embrittlement resistance was represented by a strength half-life (denoted as τ1 / 2), and determined from a relationship curve between irradiation time and strength retention.

Evaluation of heat resistance The heat resistance was measured by measuring the time required for cutting 40 denier fibers treated by treatment methods A and B, by elongating the fibers by 100%, bringing the fibers into contact with a dry heat body at 180 ° C, and cutting them.

Evaluation of light resistance The degree of coloring by light is as follows: 40 denier fibers treated by treatment methods A and B are wound in parallel on a 10 cm long, 5 cm wide aluminum plate, and the processed yarns are wound in parallel. After covering with
After irradiating with the fade meter for 40 hours, the b value of the light-irradiated portion and the light-irradiated portion covered with white paper was measured with a colorimeter (CR-121, manufactured by Minolta Co., Ltd.). The difference between the b values, Δ
b was expressed as the degree of discoloration.

Examples 1 to 3, Comparative Examples 1 to 6 In order to see the effect of the molecular weight of the benzophenone compound (A) of the formula (1) of the present invention, as shown in Table 1, as a hindered phenol compound (B), B-3 in an amount of 1.0% by weight (weight fraction based on the polymer solid content, the same applies hereinafter);
As (A), various number average molecular weights shown in Table 1 (
A polyurethane composition containing 1% by weight of A-1 in n) was prepared and evaluated as the above-mentioned physical properties. For comparison, B-3 was 1.
A polyurethane composition containing 0% by weight and 1.0% by weight of a known ultraviolet absorber and an additive-free material were prepared, a polyurethane fiber was prepared in the same manner as described above, and the yarn subjected to the treatments A and B was subjected to the above-described process. Evaluation items were evaluated. The results are shown in Table 1.

Examples 4 to 7 and Comparative Examples 7 to 9 As shown in Table 2, the benzophenone compounds (A) of the formula (1) of the present invention each contained 1% by weight of A-1 and A-.
1 and 1% by weight of B-1 and B-
2, B-3, B-5, and a known stabilizer 2,2'-methylenebis (4-methyl-6-t-butylphenol) (
n = 340), the combined effect of (A) and (B) was observed. Table 2 shows the evaluation results.

Examples 8 to 11, Comparative Examples 10 and 11 As shown in Table 3, (A), (B) and (C) (third
Grade nitrogen-containing polymer). The amounts added to the polyurethane polymer were A = 0.5% by weight, B = 1.0% by weight, and C = 3.5% by weight.

 Table 3 shows the evaluation results.

[Effects of the Invention] As shown by the results of Examples and Comparative Examples, the stabilized polyurethane composition containing the combination of stabilizers of the present invention is compared with a known polyurethane composition containing a conventional stabilizer,
The stability to heat and light is greatly improved, and the excellent stabilizing effect can be maintained even in processing under severe conditions such as processing B.

 ──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-55-54312 (JP, A) JP-A-63-139958 (JP, A) JP-A-56-125414 (JP, A) JP-A 57-54 74310 (JP, A) JP-A-1-299559 (JP, A) JP-A-62-138558 (JP, A) JP-B-43-27737 (JP, B1) JP-B-46-26860 (JP, B1) Tokiko Sho 45-34800 (JP, B1)

Claims (2)

(57) [Claims] (1) The polyurethane has the following general formula (1): (However, R ₁ is a hydrogen atom or a methyl group, R ₂ and R ₃ are a hydrogen atom or a methyl group, and at least one of R ₂ and R ₃ is a hydrogen atom, and R ₄ is a hydrogen atom or a carbon atom. And a number average molecular weight of 1,000 consisting of a repeating unit represented by the following formula:
And a hindered phenol compound having a number average molecular weight of from 600 to 10,000 in a stabilized amount. 2. Polyurethane has the following general formula (1): (However, R ₁ is a hydrogen atom or a methyl group, R ₂ and R ₃ are a hydrogen atom or a methyl group, and at least one of R ₂ and R ₃ is a hydrogen atom, and R ₄ is a hydrogen atom or a carbon atom. And a number average molecular weight of 1,000 consisting of a repeating unit represented by the following formula:
A benzophenone compound in the range of from 100,000 to
A polyurethane composition comprising (B) a hindered phenol compound having a number average molecular weight in the range of 600 to 10,000 and (C) a tertiary nitrogen-containing polymer in a stabilizing amount.