JPH0270718A - Production of polyurethane and polyol composition therefor - Google Patents

Abstract

PURPOSE:To lower foam density, avoid an insufficient initial hardness when the curing time is shortend and retard heat discoloration of a skin material, by reacting a polyisocyanate with a specific active hydrogen compd. CONSTITUTION:A polyol of the formula I (wherein R1 is 1-4C alkyl; A is 2-4C alkylene; R2 is R1 or formula II; A' is 2-4C alkylene; and m is 0-4; n>=1) having at least 5wt.% polyoxyethylene chain, 2-4 functional groups, a hydroxyl value of 15-200 and a tertiary nitrogen content of 0.3-15% (e.g., ethylene oxide- propylene oxide adduct of propylene glycol) is compounded, if necessary, with a polyether and a crosslinker to give a compsn. with a hydroxyl value of 40-200 and contg. active hydrogen compds. Said compsn. is reacted with a polyisocyanate in the presence of required amts. of a catalyst, a blowing agent and other additives to give a polyurethane with a density of 0.05g/cm<3> or higher.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for producing polyurethane and a polyol composition. More specifically, the present invention relates to a method for producing polyurethane and a polyol composition suitable for producing semi-rigid molded polyurethane foam.

[Conventional technology] PVC for automobile interior materials such as crash pads, armrests, headrests, console boxes, knee pads, etc.
(Polyvinyl chloride) skin material or PVC/ABS resin skin material and semi-rigid polyurethane foam integrally foam molded products are often used, polyether polyol, crosslinking agent, 1 blowing agent.

It is well known that a semi-rigid foam is used in which a polyol component containing a catalyst or the like as a main component reacts with an organic polyisocyanate.

Polyether polyols are used as polyol components for these applications, and amine polyols such as triethanolamine, ethylenediamine, and aminoethylpiperazine with alkylene oxide attached have also been used because of their high activity.

[Problems to be solved by the invention] However, recently there has been a strong demand for higher productivity, but conventional amine-based polyols still have insufficient activity and cannot satisfy these demands. I could not do it. Therefore, polyols with even higher activity have been strongly desired. In addition, in recent years there has been a strong demand for lighter automobiles, improved productivity, softer interior materials, etc., and there is a strong desire to reduce the weight and shorten the curing time of the semi-rigid polyurethane foams used. The lower density of the foam and shorter curing time means that when the foam is removed from the mold,
The problem of deformation of foam molded products due to insufficient initial hardness of the foam has become a major defect. Furthermore, if the amount of catalyst used is increased to shorten the curing time, there is a drawback that the heat discoloration resistance (vinyl stain) of the skin material deteriorates.

[Means for Solving the Problems] The present inventors have solved the following problems: (1) Insufficient initial hardness when polyurethane is lowered in density and curing time is shortened, (2) Deterioration in heat discoloration of the skin material, etc. As a result of intensive studies to solve these problems, the present invention has been arrived at.

That is, the present invention provides a method for producing polyurethane by reacting a polyisocyanate and an active hydrogen atom-containing compound in the presence of a catalyst 9 blowing agent and other additives if necessary. As general formula (1) (wherein R1 is an alkyl group having 1 to 4 carbon atoms, A is an alkylene group having 2 to 4 carbon atoms, R2 is an alkyl group having 1 to 4 carbon atoms, or (AO) nHl A' is An alkylene group having 2 to 4 carbon atoms, m is an integer of 0 to 4, and n is an integer of 1 or more. ~2
00 and a tertiary nitrogen atom content of 0.3 to 15%. 2. A polyol composition comprising the polyol (a) according to claim 1.

In the general formula (1), examples of the alkyl group having 1 to 4 carbon atoms in R1 include methyl, ethyl, propyl, and butyl groups. Preferred are methyl and ethyl groups.

Examples of the alkylene group having 2 to 4 carbon atoms in A include ethylene, propylene, and 1.2-, 2.3-, and 2.3-butylene groups. Preferred are ethylene and propylene groups.

Examples of the alkyl group having 1 to 4 carbon atoms for R2 include the same groups as for R1.

The alkylene group having 2 to 4 carbon atoms in A' is ethylene,
Examples include trimethylene and tetramethylene groups. Preferred are ethylene and trimethylene groups.

m is preferably θ to l. n is preferably 4 to 10
It is 0.

The polyol (a) includes dimethylaminoethylamine, dimethylaminopropylamine, dimethylaminobutylamine, diethylaminoethylamine, diethylaminopropylamine, dimethylaminobutylamine, methylethylaminoethylamine, methylethylaminopropylamine, methylethylaminobutylamine, dibutylaminoethylamine. Alkylene oxide [ethylene oxide (hereinafter referred to as (Also called EO)
, propylene oxide (hereinafter also referred to as PO), 1.
2-. Examples include adducts of 2.3- and 1.3-butylene oxide, styrene oxide, epichlorohydrin, etc., and combinations of two or more of these. When two or more alkylene oxides are used, their addition formats include block, random, and combinations thereof. Among these, block or random adducts of PO and EO of the above-mentioned active hydrogen atom-containing amine compounds are preferred.

The polyol (a) preferably has at least 5% by weight of polyoxyethylene chains. If the polyoxyethylene chain content is less than 5% by weight, the urethane foam will not be sufficiently cured and will collapse. The number of functional groups in polyol (a) is usually 2 to 4. When the number of functional groups is 1 or less, the strength of the foam is remarkable;
If it is greater than 4, the foam will shrink more.

The hydroxyl value of polyol (a) is usually 15 to 200
1, preferably 15 to 100. If the hydroxyl number of polyol (a) is less than 15, the effect of the present invention cannot be obtained, and if the hydroxyl number exceeds 200, the elongation and tear strength of the foam will decrease.

The tertiary nitrogen content of polyol (a) is usually 0.3 to 15
%, preferably 0.5~! It is 0%. If the tertiary nitrogen content is less than 0.3%, the reactivity will decrease, so the effect of the present invention cannot be fully expected, and if it exceeds 15%, the liquid flow in the mold during foaming will be impaired. Obstructed and difficult to use.

A specific example of the polyol (a) is a PO/EO block adduct of dimethylaminoethylamine (EO content 10
%, molecular weight 3500, hydroxyl number 32°0), PO/EO block adduct of dimethylaminopropylamine (EO content 18%, molecular weight 4000, hydroxyl a
i28. 0), N,Il-dimethyldiethylenetriamine block adduct of PO/EO (EO content 15%
, molecular weight 5000, hydroxyl value 33°0).

In the present invention, the following polyethers, crosslinking agents, etc. can be mentioned as active hydrogen atom-containing compounds that can be used together with polyol (a) if necessary.

Polyethers include active hydrogen atom-containing compounds [OH
, N&, Nll, COOH, etc., containing at least one alkylene oxide in the molecule, such as alcohols, phenols, amines, phosphoric acids, carboxylic acids]. - or polyethers having two or more hydroxyl groups [polyether monools and polyether polyols].

The active hydrogen atom-containing compounds used in the production of the above polyethers include (1) aliphatic, cycloaliphatic and aromatic, saturated and unsaturated, monohydric and polyhydric alcohols, such as: methanol, ethanol, Monohydric alcohols such as n-butanol, octyl alcohol, 2-ethylhexanol, lauryl alcohol, stearyl alcohol, oleyl alcohol, cyclohexanol, and benzyl alcohol (
Alkylene glycol (carbon number 2-2G) [ethylene glycol, propylene glycol, 1,4-phthanedio-7, l,3-butylene gelifol, neopentyl glycol, 't, s- glycols such as hexanediol, cyclohexanediol, cyclohexane dimetatool; glycerin, trimethylolpropane, trimethylolethane, hexanetriol, pentaerythritol, diglycerin.

α-Methyl glucoside, sorbitol, xylift.

3#8 alcohols such as mannitol, glucose, fructose, sucrose; (2) Phenols, such as: phenol, mono-
or 14fii phenols such as di-alkyl (1 to 20 carbon atoms) phenols (cresol, dinonylphenol, etc.), naphthol; hydroquinone;

Catechol, resorcinol, pyrogallol, bisphenols (bisphenol A, bisphenol sulfone,
(3) Aliphatic, alicyclic, aromatic and heterocyclic, mono- and Polyamines, such as; ammonia; alkanolamines such as mono-, di- and tri-ethanol and/or propatoolamine; mono- and di-alkyl
0) Amine, alkylene diamine (2 to B carbon atoms)
(ethylenediamine, hexamethylenediamine, etc.),
Aliphatic amines such as polyalkylene (2 to B carbon atoms) polyamines (diethylenetriamine, triethylenetetramine, etc.); aniline, phenylenediamine, diaminotoluene, xylylenediamine, methylenedianiline,
Diethyltolylenediamine.

Aromatic amines such as diphenyl ether diamine; alicyclic amines such as isophorone diamine and dicyclohexylmethane diamine; piperazine.

Aminoethylpiperazine and other special public works 1984-2104
Heterocyclic amines as described in No. 4; (4) Aliphatic, alicyclic and aromatic, saturated and unsaturated, monovalent and polyhydric carboxylic acids, such as; acetic acid, propionic acid, butyric acid, octanoic acid , monocarboxylic acids (having 1 to 20 carbon atoms) such as lauric acid, stearic acid, oleic acid, and benzoic acid; dicarboxylic acids such as adipic acid and phthalic acid; (5) phosphoric acids, such as; orthophosphoric acid, metaphosphoric acid, Examples include pyrophosphoric acid, polyphosphoric acid, phosphorous acid, etc.; and acidic esters thereof (dibutylpyrophosphoric acid, etc.), etc.; and mixtures of two or more of these.

Among these, alcohols, especially 2'
-It is trivalent.

Examples of the alkylene oxide added to the active hydrogen-containing compound include EOlPo, 1.2-, 2.3- and 1.3-butylene oxide, tetrahydrofuran, styrene oxide, epichlorohydrin, and two or more of these (e.g. EO and PO) in combination (random and/or block). Preferable is P
Combined use of O, EO, and PO/EO [random, block, and mixed systems of both (e.g., random, block, and mixed systems of both (e.g., random addition followed by EO
tip).

The number of moles of alkylene oxide added is 1 active hydrogen atom
The number is usually 5 to 100, preferably 10 to 80, particularly preferably 15 to 50.

The molecular weight of these polyethers is usually 500 to 20.
000. Preferably it is 1.500 to 10,000, more preferably 3,000 to 8,000. Graft polyols may also be used as part of the polyether (styrene in polyol (a) of format (1)).

Polymerized monomers such as acrylonitrile with a hydroxyl value of 20 to 40 can be used.

In the present invention, the amount of polyol (a) used is usually 2 to 80 parts, preferably 5 to 50 parts, per 100 parts by weight of the active hydrogen-containing compound. If two parts are left ungrooved, the effect of the present invention cannot be sufficiently obtained, and if more than 80 parts are used, there will be adverse effects such as poor liquid flow during foaming of the semi-rigid foam, resulting in molding defects.

Crosslinking agents that can be used in the present invention include ethylene glyfur, diethylene glycol, propylene glycol, glycerin, trimethylolpropane, triethanolamine, jetanolamine, and/or their PO adducts, EO adducts, PO /EO
blocks, and/or PO adducts of ethylenediamine, propylenediamine, diethylenetriamine,
Examples include EO adducts, PO/EO block and/or random adducts with a hydroxyl value of 200 to 1000.

The total hydroxyl value of the active hydrogen-containing compound containing polyol (a) used in the present invention is usually 40 to 2oo
I have. When the total hydroxyl number is less than 40, the resulting urethane foam is too soft, and when it exceeds 200, the resulting urethane foam is too hard to be used as a semi-rigid foam.

As the catalyst used if necessary in the present invention, known amine catalysts and metal catalysts used for foaming urethane foam can be used. For example, triethylamine,
Triethylenediamine, N,N.

N1. Amine catalysts such as 2-tetramethylethylenediamine, tetramethylhexamethylenediamine, tetramethylpropylenediamine, pentamethyldiethylenetriamine, dimethylbenzylamine, N-methylmorpholine, N-ditylmorpholine, dimethylethanolamine, stannous octoate .

Metal catalysts such as dibutyltin dilaurate can be mentioned. The amount used may be the same as that used for foaming general urethane foam.

Examples of the blowing agent include water and/or other blowing agents, and water and/or other blowing agents include:
In addition to water, examples include trichloromonofluoromethane and methylene chloride. The amounts used for these may be those used for foaming general urethane foam.

Furthermore, other additives such as flame retardants such as trischloroethyl phosphate, pigments such as carbon black, foam stabilizers, and other auxiliary agents may also be used.

The polyisocyanate used in the present invention is polymeric diphenylmethane diisocyanate.

A mixture of polymeric diphenylmethane diisocyanate and toluene diisocyanate, a mixture of polymeric diphenylmethane diisocyanate and pure diphenylmethane diisocyanate.

NCO-terminated prepolymer of toluene diisocyanate
Examples include NGO-terminated prepolymers of pure diphenylmethane diisocyanate.

The method for producing polyurethane may be the same as conventional methods, and either the one-shot method or the prepolymer method (semi-prepolymer method) can be applied, but the one-shot method is preferred.

Further, polyurethane can be used as polyurethane foam, elastomer, etc., but polyurethane foam is preferred. As the foaming method, any of the slab method, mold method (hot mold method, HR (high elasticity) mold method, etc.) can be applied. Polyurethane foam is super soft, flexible,
Any semi-rigid foam may be used, but semi-rigid foam is preferred.

The density of polyurethane foam is usually at least 0°05
g/cm' or more.

[Example] The present invention will be further explained below with reference to Examples, but the present invention is not limited thereto. Parts in the examples are parts by weight.

Examples 1 to 3, Comparative Examples 1 to 4 Using the foaming recipe shown in Tables 1 and 2, the urethane foam stock solution was injected into the mold to foam the semi-rigid urethane foam, and the C-hardness when the foam was removed from the mold. And the foam deformation and foam physical properties were measured.

(Foaming conditions) Mold shape: 100 mm x 20 hm x 5 hm Material: Iron Mold temperature = 40 ± 2°C Raw material stirring time: 10 seconds Kier time: 4 minutes at room temperature (Measurement conditions) C-Hardness: Based on Shore C type hardness meter.

Time from stirring to foaming Time from stirring to foaming when the foam surface is touched with a mallet stick Cream Time Nigel Time Time to start pulling threads Rise time: Time from stirring to completion of foaming (both include 10 seconds of stirring time) Cure property: Injection - Demolding After 4 minutes of demolding, press the foam with your finger and visually judge the extent of marks 0 mark (no marks) Δ mark (slight marks) × mark (obvious marks) Vinyl stain ΔE: Slash PVC skin With form 1
Represents the skin color difference after aging at 10°C for 400 hours (raw materials used) Polyol A: propylene glyfur adduct of propylene oxide/ethylene oxide, ethylene oxide content 25%, molecular weight 4000. Hydroxyl number 28.0 Polyol B; propylene oxide/ethylene oxide adduct of dimethylaminopropylamine, ethylene oxide content 18%, molecular weight 4000,
Hydroxyl number 28.0 Adduct of propylene oxide/ethylene oxide of polyol C niaminoethylpiperazine, ethylene oxide content 14%, molecular weight 80 DO, hydroxyl number 28.0U-CATIσ00: Tetramethylhexamethylenediamine DABCO33LV manufactured by San-Apro: 33% dipropylene glycol solution of triethylene diamine (manufactured by Sankyo Air Products) MRloo: Polymeric diphenylmethane diisocyanate (manufactured by Nippon Polyurethane Co., Ltd.) Table-1 Table-1 (continued) Note) DE-A diethanolamine U-CAT: TI-CATlooO DABCO : DABCO33LV MR200: Millionate NR20G CT: Crisim time (sec) GT Nigel time (sec) RT: Rise time (sec) FF density: Free form density (g/c 3) MF density: Mold 7 ohm total density (g/cv ” ) C hardness l:
Demolding C hardness (on the form) C hardness 2: Final C hardness (on the form) Hi-Nilstein: ΔE [Effects of the invention] The manufacturing method of the present invention eliminates the problem of demolition when trying to shorten the curing time and reduce the weight. This method solves the problems of insufficient curing (deformation) during molding and deterioration of heat-resistant discoloration of the epidermis.In other words, the following effects are observed.

1. No insufficient curing (deformation) of the foam was observed after shortening the curing time.

2. As shown in Example 3, the density of the foam was reduced.

31 Heat resistance discoloration of the epidermis (vinyl stain) worsening of It was possible to shorten the curing time without causing any problems.

Claims (1)

[Scope of Claims] 1. A method for producing polyurethane by reacting a polyisocyanate and an active hydrogen atom-containing compound in the presence of a catalyst, a blowing agent, and other additives if necessary, wherein the active hydrogen atom-containing compound As at least part of the general formula (
1) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(1) (In the formula, R_1 is an alkyl group with 1 to 4 carbon atoms, A is an alkylene group with 2 to 4 carbon atoms, and R_2 is an alkyl group with 1 to 4 carbon atoms. or (AO)_n, H, A' is an alkylene group having 2 to 4 carbon atoms, m is an integer of 0 to 4, and n is an integer of 1 or more). A manufacturing method for polyurethane characterized by: 2. Claim 1, wherein the polyurethane is a polyurethane foam having a density of at least 0.05 g/cm^3 or more.
Manufacturing method described. 3. The method according to claim 1 or 2, wherein the polyol (a) is a polyether polyol containing at least 5% by weight of polyoxyethylene chains in the polyol (a). 4. The method according to any one of claims 1 to 3, wherein the polyol (a) is a polyether polyol having a hydroxyl value of 15 to 200. 5. A polyol composition comprising the polyol (a) according to claim 1, which has a hydroxyl value of 15 to 200 and a tertiary nitrogen atom content of 0.3 to 15%.