JP3213625B2 - Method for producing polyether polyol - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to relates to the production how of polyether polyol.

[0002]

2. Description of the Related Art Conventionally, hard polyurethane urea four
(Hereinafter referred to as RPUF ) is a mixture of a polyether polyol, a foaming agent, a foam stabilizer, a catalyst-based component, and a polyisocyanate component typified by polymeric MDI, etc., and simultaneously proceeds with a foaming process and a polyurethane-forming process. It is manufactured by a one-shot method in which a foam is formed.

[0003] As a blowing agent used in the production of RPUF, CFC-11 (or CFC-12: for floss) has been mainly used. Water reacts with isocyanate to form a urea bond to generate carbon dioxide gas, and thus has been used supplementarily as a reactive foaming agent in combination with freon.

However, certain fluorocarbons such as CFC-11, which has been used as an excellent blowing agent, are stable in the atmosphere and diffuse to the stratosphere to destroy the earth's ozone layer. Schedules for total abolition have been determined and alternative blowing agents are urgently needed to meet this schedule.

[0005] As a foaming agent replacing CFC-11, various substances such as alternative fluorocarbons (HCFC-141b, HCFC-123, etc.) and methylene chloride have been studied. No agent has appeared.

For example, HCFC-141b, HCFC-1
Even if 23 can be actually used in the near future, it is unavoidable to use it together with water due to an increase in cost. Furthermore, since the ozone depletion potential is not 0, there is a possibility that it will eventually be abolished. Further, methylene chloride is highly toxic and strongly invades the polyurethane resin, so that it can be used only partially.

In addition, the proportion of water used as an auxiliary is increased (molar ratio of water / CFC-11 is 30-100 / 70-
0, especially when the water content is 50% or more), (a) the viscosity of the polyether polyol side is increased, the workability is deteriorated, and poor mixing is caused; (b) the balance of reactivity is poor, and the roughness is extremely coarse. (C) it becomes brittle and does not lose its flyability; (d) its mechanical strength is reduced; (e) its thermal conductivity is increased. RPU
A good RPUF cannot be produced with the polyether polyol for F.

[0008] A number of patents have been issued for sucrose-based polyether polyols for RPUF.
By defining the addition ratio of PO and EO within a certain range, the viscosity is lower than that of a conventional polyether polyol having the same average hydroxyl functionality and hydroxyl value, and water, CFC-
11. There is no description about good compatibility with Polymec MDI and good reaction balance with water. Furthermore, when a polyether polyol in which the above-mentioned starting materials and the like are specified is used as a main polyether polyol, and a mixed system of water and CFC-11 is used as a blowing agent, the molar ratio of water / CFC-11 is reduced. 30 to 10
Nothing mentions that the problems of (a) to (e) can be solved or reduced in the range of 0/70 to 0, particularly 50% or more of water.

[0009]

SUMMARY OF THE INVENTION The present inventors have considered these situations and have been working to find a polyether polyol for the production of RPUF which can be used as a main blowing agent in order to meet the social demands. As a result of repeated studies, the present invention has been reached.

It is therefore an object of the present invention is to a child provides a method for producing a polyether polyol which can greatly reduce the amount of fluorocarbon blowing agent without causing the above problems when RPUF production.

[0011]

Means for Solving the Problems That is, the method of producing the polyether polyols of the present invention, sucrose, one also selected from a sugar alcohol having 4 or more hydroxyl groups in one molecule
Means two or more sugar alcohols (but no more than four
Excluding sugar alcohols with full hydroxyl groups)
"Sugar alcohol having four or more hydroxyl groups in one molecule
And a polyether polyol having a hydroxyl value of 600 mg KOH / g or more having three hydroxyl groups in one molecule, and having an average number of functional groups of 4.0 to 6.0.
Is characterized in that an alkylene oxide consisting of 2 to 50% by weight of ethylene oxide and 98 to 50% by weight of propylene oxide is simultaneously added to the starting material.

Next, the present invention will be described in detail. The starting material of the polyether polyol of the present invention is
Sucrose, sugar alcohols having four or more hydroxyl groups in one molecule, and hydroxyl value 60 having three hydroxyl groups in one molecule
It is a mixture of polyether polyols of 0 mgKOH / g or more.

Among them, sugar alcohols having four or more hydroxyl groups in one molecule include sorbitol, pentaerythritol, methyl glucoside and the like, and these may be used alone or in combination.

A polyether polyol having three hydroxyl groups in one molecule and having a hydroxyl value of 600 mg KOH / g or more is defined as a polyol having three hydroxyl groups in one molecule such as glycerin or an alkylene oxide such as ethylene oxide or propylene oxide. A polyether polyol having a hydroxyl value of 600 mg KO
H / g or more, preferably 600 to 850 mgKOH / g
belongs to. These may be used alone or in combination.

Sucrose, sugar alcohols having four or more hydroxyl groups in one molecule, and polyether polyols having three hydroxyl groups in one molecule and having a hydroxyl value of 600 mgKOH / g or more have an average number of functional groups of 4 in the mixture. 0.0 to 6.0
Mix so that The average number of functional groups in the mixture is 4.0
If it is out of the range of 6.0, if it is less than 4.0, the physical properties will be insufficient, and the foam will shrink. If it exceeds 6.0, the viscosity of the product will increase (several tens of thousands cps or more), which is inappropriate.

Next, an alkylene oxide is added to the above starting material to obtain the polyether polyol of the present invention. The alkylene oxide is ethylene oxide 2 to 5
0% by weight and 98 to 50% by weight of propylene oxide. If the ethylene oxide content is lower than 2% by weight, the viscosity of the product (polyether polyol) increases, and the viscosity of the stock solution increases, or if the foam is formed, the cells become coarse, causing a problem in adhesion to the surface material. And not preferred,
If the content exceeds 50% by weight, when the foam is formed, there is a problem that the compressive strength is lowered and the foam is not suitable.

The addition of the alkylene oxide is carried out according to a conventional method, using an alkali catalyst such as potassium hydroxide 0.05 to 0.5.
Temperature 110-130 ° C in the presence of 0% (vs. starting material),
It is performed under the condition of a pressure of 2.5 to 6.0 kg / cm ² , and the adding method may be random or block. The obtained polyether polyol of the present invention has a hydroxyl value of 250 to 5
When the viscosity is within the range of 00 mg KOH / g,
0 cps or less, the viscosity of the undiluted solution in the form of a foam is reduced, and machine foaming becomes easy, and the foam properties also include abrasion loss (flyability), fine cells, compressive strength, thermal conductivity, adhesion to face materials, etc. Is also preferable.

The polyether polyol of the present invention gives RPUF by reacting with a polyisocyanate in the presence of a blowing agent, a catalyst and other auxiliaries usually used in the production of RPUF.

At this time, the polyether polyol of the present invention may be used alone, but the polyether polyol of the present invention is at least 50% by weight (preferably at least 60% by weight).
And a mixed polyether polyol comprising 50% by weight or less (preferably 10 to 40% by weight) of a polyether polyol having 3 to 6 hydroxyl groups in one molecule. By using a polyether polyol having 3 to 6 hydroxyl groups in one molecule in this manner, the effect of further reducing the abrasion loss (flyability) and the compressive strength in the foam properties can be obtained.

Examples of the polyisocyanate used in the production of R PUF include polymeric MDI (polymethylene polyphenyl isocyanate), diphenylmethane diisocyanate, trimethylene diisocyanate, and those partially modified by various methods and compounds. Is mentioned.

The blowing agent used for the production of R PUF is a mixed system of water and chlorofluorocarbon (such as CFC-11), and [water] /
It is preferable to use it in such a range that the molar ratio of [water + CFC] is 0.3 to 0.5.

As the catalyst used for the production of RPUF , for example, tertiary amines such as trimethylenediamine, tetramethylhexamethylenediamine, trimethylaminoethylpiperazine, and pentamethyldiethylenetriamine are exemplified. The amount of the catalyst used is 0.2 to 1.5% by weight based on 100% by weight of the polyol component.
It is preferable to use in the range of.

As the foam stabilizer used in the production of RPUF , a commonly used organosilicone compound is preferable, and in addition, use of a fluorine-based surfactant or the like is also preferable.
The use amount of the foam stabilizer is preferably in the range of 0.5 to 2.0% by weight based on 100% by weight of the polyol component.

In addition, trischloroethyl phosphate (TC) which is a flame retardant usually used in the production of RPUF
Auxiliaries such as EP), trisdichloropropyl phosphate, bis (2,3-dibromopropyl) dichloropropyl phosphate, and tris (2,3-dibromopropyl) phosphate can also be used as appropriate.

The R PUF has an NCO / OH (NCO Index) of 100 to 130 by a usual one-shot method.
Can be manufactured as

[0026]

EXAMPLES (I) Production of Polyether Polyol Example 1 An autoclave (30 liters) equipped with a heating / cooling / stirring / decompression device was charged with 3.62 kg of sucrose, 1.09 kg of sorbit, and a polystyrene manufactured by Asahi Denka Kogyo Co., Ltd. Ether polyol G-260 (molecular weight 260 obtained by adding propylene oxide to glycerin, hydroxyl value 650 mg KOH /
8.68 kg of trifunctional polyether polyol (g) (average number of hydroxyl functional groups in the mixture is 4.5), 55 g of potassium hydroxide is added as a catalyst, the temperature is 120 ° C., the pressure is 2.5 to 6.0 kg / cm ^2. Then, 2.8 kg of ethylene oxide and 11.3 kg of propylene oxide were fed at the same time in the proportion of the charged weight. After feeding, the mixture was aged for 1 hour, and stripped of remaining traces of ethylene oxide and propylene oxide. Next, the mixture is purified at normal temperature to reduce the water content to 0.1% or less, and the stabilizer 2,6-di-tert-butyl-4-methylphenol (BHT) is used.
500 ppm was added. The obtained polyether polyol (A) of the present invention has an average number of hydroxyl functional groups of 4.5, a hydroxyl value of 450 mgKOH / g, and a viscosity of 3400 cp / 25 ° C.
Met.

Example 2 In an autoclave (30 liters) equipped with a heating / cooling / stirring / decompression device, 3.42 kg of sucrose, 1.82 kg of sorbit, polyether polyol G-200 (Asahi Denka Kogyo Co., Ltd.) Oxide-added molecular weight 200, hydroxyl value 842 mg KOH /
of trifunctional polyether polyol) (average hydroxyl functionality of the mixture: 5.7), 48 g of potassium hydroxide as a catalyst, a temperature of 120 ° C. and a pressure of 2.
5 to 6.0 kg / cm ² , and ethylene oxide 5.0
kg and 11.7 kg of propylene oxide were fed at the same time in the proportion of the charged weight. After the feed, the mixture was aged for 1 hour, and the remaining traces of ethylene oxide and propylene oxide were stripped. Next, the mixture is purified at normal temperature to reduce the water content to 0.1% or less, and the stabilizer 2,6-di-tert-butyl-4-methylphenol (BHT) 50
0 ppm was added. The obtained polyether polyol (B) of the present invention had an average number of hydroxyl functional groups of 5.7, a hydroxyl value of 400 mgKOH / g, and a viscosity of 3,600 cp / 25 ° C.

Comparative Example 1 4.90 kg of sucrose and 3.27 kg of glycerin were charged into an autoclave, 55 g of potassium hydroxide was added as a catalyst, the temperature was 120 ° C., the pressure was 0.2 to 6.0 kg / cm.
^{In step 2} , 19.3 kg of propylene oxide was fed. After feeding, the mixture was aged for 1 hour, and the remaining trace amount of propylene oxide was stripped. Next, the product is purified by a conventional method, the water content is reduced to 0.1% or less, and the stabilizer BHT is added to 50%.
0 ppm was added. The resulting polyether polyol (C) had an average number of hydroxyl functional groups of 4.5 and a hydroxyl value of 450 m.
gKOH / g, viscosity 6500 cp / 25 ° C.

Comparative Example 2 4.90 kg of sucrose and 3.27 kg of glycerin were charged in an autoclave, 55 g of potassium hydroxide was added as a catalyst, the temperature was 120 ° C., the pressure was 2.5 to 6.0 kg / cm.
^{In step 2} , 3.86 kg of ethylene oxide and 15.4 kg of propylene oxide were simultaneously fed in proportion to the charged weight. After feeding, the mixture was aged for 1 hour, and stripped of remaining traces of ethylene oxide and propylene oxide. Next, the product was purified by a conventional method, the water content was reduced to 0.1% or less, and 500 ppm of a stabilizer BHT was added. The obtained polyether polyol (D) had an average number of hydroxyl functional groups of 4.5, a hydroxyl value of 450 mgKOH / g, and a viscosity of 400 mg.
It was 0 cp / 25 ° C.

Comparative Example 3 3.62 kg of sucrose, 1.09 kg of sorbitol, Example 1
8.68 kg of G-260 used in the above was charged into an autoclave, 55 g of potassium hydroxide was added as a catalyst, and 14.1 kg of propylene oxide was fed at a temperature of 120 ° C. and a pressure of 0.2 to 6.0 kg / cm ² . After feeding, the mixture was aged for 1 hour, and the remaining trace amount of propylene oxide was stripped. Next, the product was purified by a conventional method, the water content was reduced to 0.1% or less, and 500 ppm of a stabilizer BHT was added. The resulting polyether polyol (E) had an average hydroxyl functionality of 4.5, a hydroxyl value of 450 mg KOH / g,
The viscosity was 4600 cp / 25 ° C.

(II) Production of RPUF (Reference Example) RPUF was produced by free foaming by a hand mixing method using the polyether polyols obtained in Examples 1 and 2 and Comparative Examples 1 to 3. That is, a premix is prepared by previously blending additives such as a foaming agent, a foam stabilizer, and a catalyst with 300 g of a polyether polyol (foaming scale 3 times), and a liquid temperature is controlled to 23 ± 2 ° C. Keep it. Separately, a polyisocyanate whose solution temperature was controlled at 23 ± 2 ° C. was added to the premix, and the mixture was rapidly stirred for 12 seconds using a turbine-type two-stage mixer (2000 to 2500 rpm), and the mixture was opened at the top.
Inject into the box of cm × 30cm × 30cm and RPU
F was produced. The formulation and physical properties are shown in Table 1 below.

[0032]

[Table 1]

Table 1 Note: PE-250: pentaerythritol PO adduct Hydroxyl value 450 mg KOH / g L-5420: Nippon Unicar organic silicone foam stabilizer TEPA-L33: Tosoh catalyst 33% DPG solution of triethylenediamine TOYOCATMR: Tosoh catalyst N, N, N ', N'tetramethylhexamethylenediamine CFC-11: Daikin foaming agent DF-11U (trichloromonofluoromethane) Sumidur 44V20: Sumitomo Bayer Urethane polymer MDI face material: Asphalt roofing paper Polyether polyol viscosity: unit cp / 25 ° C. Stock solution viscosity: unit cp / 25 ° C. Core density: unit kg / cm ³ Abrasion loss: unit mg / 10 times Compressive strength: unit kgf / cm ² Thermal conductivity: unit kcal / m・ Time ・ ℃

As is clear from Table 1, by using the polyether polyol of the present invention, the viscosity of the premix is reduced, the cell state of the obtained foam is fine, and the flyability is small (the loss of abrasion is reduced). reference). In addition, a stable foam having low thermal conductivity is obtained.

[0035]

By using the polyether polyol obtained by the method of the present invention, the amount of chlorofluorocarbon used in the production of RPUF can be reduced by 30% or more.
The physical properties of UF are very good.

Continuation of the front page (72) Inventor Kazuma Fujima 7-35 Higashi Oku, Arakawa-ku, Tokyo Asahi Denka Kogyo Co., Ltd. (72) Inventor Shuichi Kaneda 7-35 Higashi Oku, Arakawa-ku, Tokyo Asahi Denka Kogyo (72) Inventor Jin Saito 7-2-35 Higashiogu, Arakawa-ku, Tokyo Asahi Denka Kogyo Co., Ltd. (56) References JP-A-57-55927 (JP, A) JP-A-56-149428 ( JP, A) (58) Fields surveyed (Int. Cl. ⁷ , DB name) C08G 65/28 C08G 18/65-18/66

Claims (1)

(57) [Claims] 1. A sucrose, one or more saccharides selected from sugars alcohol having 4 or more hydroxyl groups in one molecule
Alcohols (but less than 4 hydroxyl groups per molecule)
And a polyether polyol having a hydroxyl value of 600 mg KOH / g or more having three hydroxyl groups in one molecule, and having an average number of functional groups of 4.0.
Starting materials that are ~ 6.0, include ethylene oxide 2-5
A method for producing a polyether polyol, comprising simultaneously adding an alkylene oxide consisting of 0% by weight and 98 to 50% by weight of propylene oxide.