JPS61203115A - Production of polyurethane resin - Google Patents

Abstract

PURPOSE:To obtain a polyurethane resin which has excellent weather resistance and can stand long-term use, by producing the polyurethane resin by using an ultraviolet absorber, a specified phosphite and a specified semicarbazide. CONSTITUTION:A polyurethane resin is produced from an isocyanate compound and an active hydrogen-containing compound by using a stabilizer comprising an ultraviolet absorber (a), a phosphate (b) represented by formula I and having a phosphorus content of 4.0-14.0wt% and a 1,1-dialkyl-substituted semicarbazide or carbazinate (c) having a group of formula II, III or IV (wherein R1, R2 and R3 are each alkyl, cycloalkyl, aryl or the like and R4 and R5 are each 1-10C alkyl or substituted alkyl).

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for producing stabilized polyurethane resins. More specifically, the present invention relates to a method for producing a polyurethane resin that is extremely stable against external factors such as light, heat, moisture, oxygen, and combustion gas.

[Conventional technology]

Polyurethane is a polymer with excellent impact resistance, chemical resistance, abrasion resistance, cold resistance, etc., and is therefore a material that has been conventionally used in various fields and applications. However, on the other hand, polyurethane also has the property of being easily affected by external factors such as light, heat, moisture, oxygen, and combustion gas, and these external factors can affect the surface condition of polyurethane molded products. deterioration, i.e., surface cracking,
Phenomena that are unfavorable to the quality of polyurethane products, such as occurrence of cranks and changes in hue, occur.

For this reason, various stabilizers have been developed for the purpose of improving polyurethane's poor weather resistance against these external factors. For example, in JP-A-56-100848, phenylenediamine compounds and sterically hindered phenol compounds, phenylenediamine compounds and phosphite compounds, phenylenediamine compounds and quinoline compounds, phenylenediamine compounds and benzotriazole A phenylenediamine compound and a thiourea compound, a phenylenediamine compound and a piperidine compound, or a phenylenediamine compound and a metal oxide are used as stabilizers for polyurethane. or,
In JP-A-57-49653, a hindered phenol compound and a phosphorous acid ester are used to improve the weather resistance of polyurethane.

[Problem that the invention seeks to solve]

However, the stabilizers for polyurethane that have been developed so far are not necessarily satisfactory in terms of maintaining the whiteness of white polyurethane. That is, the stabilizer disclosed in JP-A No. 56-100848 serves the purpose of preventing gloss fading and cranking of colored polyurethane, but it does not contain a phenylenediamine compound as an essential component. Therefore, if it is used in white polyurethane, it will cause yellowing, which is undesirable.

Furthermore, the stabilizer disclosed in JP-A No. 57-49653 is inferior in terms of sustainability of effect;
It cannot be said to be sufficient.

As mentioned above, various stabilizers for polyurethane are being developed for the purpose of producing polyurethane resins with excellent stability that can withstand long-term use, but it is still not enough. There is a strong desire for the emergence of polyurethane with excellent weather resistance that can withstand long-term use.

[Means for solving problems]

The present inventors have solved the above-mentioned problems, namely, that a stabilizer that is excellent in maintaining the whiteness of white polyurethane has not been obtained, and that an excellent polyurethane that can withstand long-term use has not been obtained. In order to solve this problem, as a result of extensive research, we have arrived at the present invention. That is, in producing a polyurethane resin using an isocyanate compound and an active hydrogen-containing compound, the present invention provides (a) an ultraviolet absorber and (b) a compound of the general formula (I) (Rt-Rs is the same or different alkyl group, cycloalkyl group, aryl group, alkylaryl group, aralkyl group), and its phosphorus content is 4
．． Phosphite in the range of 0 to 14.0% by weight and (c) general formulas (II) to (IV) (wherein R# and R2 are the same or different and have 1 to 1 carbon atoms)
10 alkyl group or substituted alkyl group, R
# and R6 may both constitute the same ring, and the ring may be a heterocycle. The present invention provides a method for producing a polyurethane resin, characterized in that a 1,1-dialkyl-substituted semicarbazide or carbazic acid ester having the following group is used as a stabilizer for polyurethane.

Examples of the ultraviolet absorber that can be used in the present invention include generally known ultraviolet absorbers such as salicylic acid derivatives, benzophenone derivatives, benzotriazole derivatives, nitrile derivatives, and oxalic acid anilide derivatives. Most preferred for use are benzotriazole derivatives. Specific examples of benzotriazole derivatives include 2-(2°-hydroxy-5′-methylphenyl)benzotriazole,
2-(2°-hydroxy-5'-t-butylphenyl)
Benzotriazole, 2-(2'-hydroxy-3',5'-di-t-butylphenyl)benzotriazole, 2-(2'-hydroxy-3''-t-butyl-5'
-methylphenyl)-5-chlorobenzotriazole,
2-(2°-hydroxy-3',5'-di-t-butylphenyl)-5-chlorobenzotriazo71/,2-
(2''-hydroxy-3',5''-dialkyl phenyl)benzotriazole and the like can be mentioned.

The above ultraviolet absorbers can be used in the present invention alone or as a mixture of two or more.

Next, the phosphite compound represented by the general formula (1) is a compound represented by the general formula (I) in which R, R, and R meet the above conditions. Any one may be used if available, but the phosphorus content is 4.0 to 14
．． 0% by weight, and 6.0-8.0% by weight is particularly preferred. Specific examples of these include triisodecyl phosphite, phenyl diisodecyl phosphite, diphenylnonylphenyl phosphite, and triisooctyl phosphite.

These phosphite esters can be used in the present invention alone or as a mixture of two or more.

The 1,1-dialkyl group-substituted semicarbazide or carbazic acid ester used in the present invention has the following general formulas (If) to (IV) (where R4 and R3 are the same or different and are an alkyl group having 1 to 10 carbon atoms). , or represents a substituted alkyl group, R4 and R% may both constitute the same ring, and the ring may be a heterocycle.) 1,1-dialkyl-substituted semicarbazide or Examples of carbazic acid esters include the following.

(A) (CH3)tNNHcONH(CHz)JHC
ONHN(C)b)z Melting point (Fp) 144-146℃ (B) Vinylet triisocyanate (DAS 1
．． 101.394) OCN (CHz) &NC0NH (CHri 6NC0C
0NH(CTo)JCO +3 mol 1.1-dimethylhydrazine (C) Biulet triisocyanate (same as B)
+ 2 moles 1.1-dimethylhydrazine 1 mole ethyleneimine (D) Biulet triisocyanate (same as B)
+ 1 mol 1,1-dimethylhydrazine 2 mol ethyleneimine (E) buret triisocyanate) (same as B)
+3 mol N-amino-morpholine (F) Biulet triisocyanate (same as B)
+2 mol N-amino-morpholine 1 mol ethyleneimine (G) 1,1,5.5-tetramethylcarbohydrazide (CH,)JNHCONHN(CH,)z Fp
151-153℃(H) (CHI 3>tNNH
cONHNHcONl((CHI) &NHCONI(
NHCONNHN (CHzh Pp225 227℃F
p 173-175℃ Fp 196-199℃ pp 78-80℃ (L) C+sH*tNHCONHN(CO:+)z
Fp 74-76℃ Isomer mixture -NHCONHN (CH3) zF
p 198-199°C Pp 250°C n, z.

Fp 246-247 ℃ (X) (CHI)JNHCOOCHzCHzOC
ONHN(CHs)z These 1,1-dialkyl-substituted semicarbazides or carbazic acid esters are used alone or as a mixture of two or more in combination with the ultraviolet absorber and tertiary phosphite of the present invention.

The phosphorus content of the phosphite used in the present invention is
Although it can be obtained through simple calculations, it can be obtained experimentally as follows.

(1) Preparation of test solution Weigh accurately 0.1 g of sample (containing 4 to 16@g of phosphorus) into a 100 ml Kjeldahl flask, and add 2 ml of concentrated sulfuric acid.
Before heating and carbonizing, add 30% hydrogen peroxide drop by drop to decompose the solution until it becomes transparent, then ignite until white smoke of sulfuric acid comes out. After cooling, this solution was heated to 100%
Transfer to an m1 volumetric flask and add water up to the marked line to use as the test solution.

(2) Creating a calibration curve Phosphorus standard solution (4.3939 g of monopotassium phosphate dissolved in water to make 11) 0.2.4.6.8 sol
Place each in a 100ml volumetric flask and add 50ml of water to each. Molybdovanadate solution 2
Add water to make 100ml and leave it for 30 minutes. This solution is transferred to a 10 mm cell, the absorbance at 400 nm is measured using a blank test solution as a control solution, and a calibration curve is created.

(3) Pour 5 ml of the measurement test solution into a 100 ml volumetric flask, and add approximately 5 ml of water.
Add 0 ml and 20 ml of molybdovanadate solution,
The following operations are performed in the same manner as in the preparation of the calibration curve, the absorbance is measured, and the phosphorus content percentage is calculated from the calibration curve.

The amount of the stabilizer used in the present invention is not particularly limited and is arbitrarily determined depending on the conditions under which the polyurethane composition is used, but it is usually an ultraviolet absorber, a tertiary phosphite, 1.1- The dialkyl-substituted semicarbazide or carbazic acid ester each ranges from 0.05 to 5% by weight, preferably from 0.1 to 3% by weight of the polyurethane. If the amount added is less than this range, the stabilizing effect will be low, and if it is more than this range, the physical properties such as strength and elongation of the product will be lowered, which is not preferable.

Regarding the method of adding the stabilizer used in the present invention, it is preferable to disperse the stabilizer in advance in a part of the raw material for polyurethane production or to heat and dissolve it. It is preferable to blend the phosphoric acid ester with the isocyanate compound.

The stabilizer used in the present invention can be used in the production of any generally known polyurethane, and when the polyisocyanate compound component is, for example, toluene diisocyanate, m-phenylene diisocyanate, p-phenylene diisocyanate, xylene diisocyanate,
, 4'-diphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, polymethylene polyphenylisocyanate), 3.3
”-dimethyl-4,4′-diphenylmethane diisocyanate, 3,3°-dimethyl-4,4′-biphenylene diisocyanate, 3,3′-dichloro-4,4′-biphenylene diisocyanate, 4.4”-biphenylene diisocyanate, It can be used when producing polyurethane using polyisocyanate compounds such as 1,5-naphthalene diisocyanate, mixtures or modified products thereof, or prepolymers thereof.

In particular, toluene diisocyanate, 4.4'-diphenylmethane diisocyanate, or mixtures thereof,
It is preferably used when producing polyurethane using a modified product or a prepolymer thereof.

In addition, examples of active hydrogen-containing compounds used in producing polyurethane in the present invention include ethylene glycol, propylene glycol, 1,4-butanediol, neopentyl glycol, 1,6-hexanediol, glycerin, and trimethylolpropane. , 1.
Low molecular weight polyols such as 2.6-hexanediol and pentaerythritol, amine compounds such as ethylenediamine, 4.4'-methylenebis-2-chloroaniline, and 4.4'-methylenebis-2-ethylaniline, or low molecular weight polyols such as 2.6-hexanediol and pentaerythritol; Examples include polyether polyols and polytetramethylene ether glycols obtained by adding alkylene oxides such as ethylene oxide and propylene oxide to polyols or amine compounds, and furthermore, ethylene glycol, propylene glycol, 1.4
-Polyhydric alcohols such as butanediol and phthalic acid,
Polyester polyols, polycaprolactone polyols, polycarbonate polyols, acrylic polyols, castor oil, which are condensation products with polybasic acids such as maleic acid, malonic acid, succinic acid, adipic acid, and terephthalic acid and have a hydroxyl group at the end. Examples include tall oil. In addition, at the end of the molecule, there are hydroxyl groups, amino groups, imino groups,
Liquid rubbers having active hydrogen groups such as carboxyl groups and mercapto groups and mixtures thereof can also be used.

In the production of polyurethane in the present invention, a reaction catalyst may be added in order to lower the reaction temperature or shorten the reaction time. Specific examples of the reaction catalyst include triethylenediamine, Examples include amine compounds such as tetramethylethylenediamine and tetramethylhexanediamine and their salts, organometallic compounds such as dibutyltin dilaurate, tin octylate, lead octylate, and manganese octylate, and mixtures thereof.

In addition, as auxiliary ingredients, foaming agents such as water and low-boiling organic solvents,
Colorants such as titanium white and carbon black, fillers such as calcium carbonate, silica, clay, organic fibers and inorganic fibers, softeners such as process oil, foam stabilizers, antistatic agents, antioxidants, light stabilizers, etc. can also be added as appropriate.

〔Example〕

The present invention will be specifically described below with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples. Furthermore, in Examples and Comparative Examples, "parts" are all parts by weight.

Examples 1 to 7 Polyester polyol (hydroxyl value 86, average molecular weight 1
300) Add a predetermined amount of an ultraviolet absorber and a 1,1-dialkyl-substituted semicarbazide or carbazic acid ester shown in Examples 1 to 7 in Table 1 to 100 parts, and heat the mixture at 60 to 80°C for 2 to 6 hours. The mixture was heated and stirred for an hour to dissolve it.

To this polyol component, 12 parts of ethylene glycol, 0.4 parts of water, 0.8 parts of triethylene diamine, and 1 part of a silicone foam stabilizer were added and mixed, and this was used as a polyol component.

Next, a polyurethane prepolymer (NC0%,
18.5) were added and mixed with a predetermined amount of phosphorous acid ester shown in Examples 1 to 7 in Table 1, and this was used as an isocyanate component.

83 parts of the above polyol component and 10 parts of the isocyanate component
After thoroughly mixing and stirring 0 parts, it was injected into an aluminum mold at 45 to 50°C coated with a silicone mold release agent, and taken out after 5 minutes to form a white cured product sheet with a thickness of 5III+ (15
0 x 150 parts m) was obtained.

Comparative Examples 1 to 5 In Examples 1 to 7, stabilizers were added, but in Comparative Example 1, polyurethane was produced without adding any stabilizer, and in Examples A similar test was conducted.

In Comparative Example 2, polyurethane was produced by adding only the ultraviolet absorber used in Examples 1 and 2 to the polyol component as a stabilizer.

In Comparative Example 3, polyurethane was produced by adding only the phosphorous ester used in Example 2 to the isocyanate component as a stabilizer.

In Comparative Example 4, 1, 1- used in Examples f and 3
Polyurethane was produced by adding only dialkyl-substituted semicarbazide as a stabilizer to the polyol component.

In Comparative Example 5, the ultraviolet absorber used in Examples 1 and 3 and 1,1-dialkyl-substituted semicarbazide were added as stabilizers to the polyol component to produce polyurethane.

The specific means for producing polyurethane in Comparative Examples 1 to 5 above are all the same as in the Examples except for the operation related to adding a stabilizer.

The 12 types of polyurethane sheets obtained in Examples 1 to 7 and Comparative Examples 1 to 5 were subjected to a 30-hour irradiation test using a carbon arc sunshine weather meter, and then the degree of yellowing of the test pieces was measured. It was measured using a color machine and expressed as a yellow index (YI value). The results are shown in Table 1.

The test machine used in the experiment is as follows.

(1) Carbon arc weather meter; Suga Test Instruments ■ Dyu Cycle Sunshine Super Long Life Weather Meter WEL-3UN-DC type (2) Embellishing machine; Suga Test Instruments ■ SM Color Computer SM-3 [Effects of the invention] As specifically shown in the detailed description of the invention and the examples, the polyurethane produced according to the present invention is
As the isocyanate component of the polyurethane raw material,
Toluene diisocyanate or 4.4 which is easily colored
Even polyurethanes made with diphenylmethane diisocyanate, etc., have the property of being resistant to discoloration, something that could not be achieved by methods using previously known stabilizers. The present invention makes it possible to maintain extremely high commercial value of sports shoes and other urethane products that particularly require whiteness.

Claims (1)

[Claims] 1. When producing a polyurethane resin using an isocyanate compound and an active hydrogen-containing compound, (a) an ultraviolet absorber and (b) a general formula (I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (I) (R_1, R_2, R_3 represent the same or different alkyl group, cycloalkyl group, aryl group, alkylaryl group, aralkyl group),
and a phosphite ester whose phosphorus content is in the range of 4.0 to 14.0% by weight, and (c) general formulas (II) to (IV) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (II) ▲ Mathematical formulas , chemical formulas, tables, etc. ▼ (III) ▲ Numerical formulas, chemical formulas, tables, etc. ▼ (IV) (In the formula, R_4 and R_5 are the same or different and represent an alkyl group having 1 to 10 carbon atoms or a substituted alkyl group. 1,1-dialkyl-substituted semicarbazide or carbazic acid ester having the group R_4 and R_5 may both constitute the same ring, and the ring may be a heterocycle as a stabilizer for polyurethane. 2, a method for producing a polyurethane resin characterized in that it is used as a phosphite ester represented by the general formula (I),
．． A method 3 for producing a polyurethane resin according to claim 1, which has a phosphorus content of 0 to 8.0% by weight. A method for producing a polyurethane resin according to claim 1, which is blended into