JP2836004B2 - Method for dehydrating molasses-containing polyol composition and molasses-containing polyol substantially free of water - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for dehydrating a polyol composition containing molasses and to a polyol composition containing substantially anhydrous molasses.

[0002]

2. Description of the Related Art Plastics are easy to process, cost,
Currently widely used in terms of lightness and ease of use, but unlike naturally occurring polymer compounds, it is hardly decomposed by microorganisms in nature, causing environmental pollution and causing major social problems It has become.

[0003] Therefore, there has been a demand for the development of a so-called biodegradable plastic in which many plastics are easily decomposed by the action of soil bacteria or the like even when they are discarded as waste.

[0004] Among plastics, polyurethane is prepared by reacting a polyol component and an isocyanate component. However, this plastic has almost no biodegradability like other plastics, and foamed polyurethane has a large capacity, so that it is environmentally friendly. It was a major source of pollution.

The inventors of the present invention have conducted studies to obtain a biodegradable polyurethane. As a result, a polyol composition obtained by mixing molasses with a polyhydric alcohol, which is a raw material of polyurethane, is used as a polyol component. (Japanese Patent Application No. 3-33302).
issue).

[0006]

However, when a polyurethane is prepared using the above-mentioned polyol composition, there are problems such as difficulty in controlling foaming and progress of an exothermic reaction. However, there is a drawback that a slow polyurethane cannot be obtained. In addition, there is a problem that this polyol composition cannot be used for non-foamed polyurethane for producing a polyurethane sheet or the like. These drawbacks are that the moisture contained in molasses
It is said that the resin composition inevitably remains in the polyol composition and the foaming reaction between water and isocyanate preferentially proceeds during the polymerization reaction.

That is, molasses generally contains about 17 to 25% by weight of water, but the isocyanate component which reacts with the polyol component has high reactivity with water and reacts with water to form carbon dioxide. Form, form. If the amount of water in the polyol component is large, the foaming reaction between the isocyanate component and water proceeds preferentially, and the gelation reaction between the isocyanate and the polyol does not sufficiently proceed. Insufficiency and the like occur, and the strength of the entire polyurethane decreases. Further, since the reaction between water and isocyanate is an exothermic reaction, the presence of excess water causes the inside of the polyurethane to burn. Further, in non-foamable polyurethane, the existence of the foaming reaction itself was a problem.

[0008]

Means for Solving the Problems In view of this situation, the present inventors have conducted studies and found that in order to solve the above-mentioned problems, a polyol composition containing molasses (hereinafter referred to as "molasses polyol"). )), The inventors thought that it was sufficient to substantially remove water from the inside, and succeeded in producing a substantially anhydrous molasses polyol. However, it has been industrially extremely difficult to remove water from molasses polyol.

That is, in order to industrially remove water from the polyol composition, it is necessary to concentrate under reduced pressure with a rotary evaporator or the like. However, if the pressure is rapidly reduced, the polyol composition foams violently, However, there is a problem that it takes only several tens of hours to reduce the water content to a predetermined concentration.

Therefore, as a result of further research on a method of industrially dehydrating a molasses polyol, it has been found that foaming can be almost prevented by adding a silicone surfactant to the polyol composition and then reducing the pressure.

The present invention has been accomplished based on these findings, and it is an object of the present invention to remove water after adding a silicone surfactant to a molasses and a polyol composition containing a polyhydric alcohol. Disclosed are a method for dehydrating a polyol composition and a substantially anhydrous molasses polyol.

In the present invention, the molasses polyol to be subjected to a dehydration treatment is prepared by mixing a polyhydric alcohol conventionally used in the preparation of polyurethane with molasses and removing insolubles. The term "substantially anhydrous" as used herein refers to a foaming reaction between water and an isocyanate from a state in which only a sufficient amount of water can be added to control foaming in a polyurethane polymerization reaction. Means that water is contained only to the extent that is not recognized.
More specifically, it means a state containing only about 3% by weight or less of water.

The molasses used for preparing the molasses polyol is obtained from sugarcane, sugar beet, etc., and may be purified molasses, molasses, or molasses obtained after sugar production. However, molasses is advantageous in terms of economy.

Examples of polyhydric alcohols include polyester polyols (PE) such as ethylene glycol, glycerin, polyethylene glycol (PEG), polypropylene glycol (PPG), and polycaprolactone.
S) and the like, among which ethylene glycol, glycerin and P having an average molecular weight of 200 to 400
The low molecular polyol selected from EG has an action of dissolving molasses, and its blending is essential.

Furthermore, molasses acts as a hard segment in the polyurethane, so that the incorporation of molasses imparts flexibility to the hardened polyurethane, and in order to replace it with a soft one, PEG, an average molecular weight of 600 to 3000, P
Polymer polyols such as PG and PES can be blended as so-called plasticizers.

In the preparation of the above molasses polyol, the preferable blending amount of the polyhydric alcohol is 50 to 80% by weight.
(Hereinafter simply referred to as “%”), and a preferable amount of molasses is 20 to 50%.

In the industrial dehydration method for molasses polyol, examples of the silicone surfactant added to the molasses polyol include an organic silicone block copolymer (for example, polyether / siloxane block copolymer) and the like. Examples of commercially available products include NUC Silicone L-520 and the like. The addition amount of the silicone-based surfactant may be about 0.5 to 5% with respect to the polyol composition from the viewpoint of effect and economy.

The silicone-based surfactant may be added to a molasses polyol in which molasses and a polyhydric alcohol are sufficiently stirred and mixed, or simultaneously added with molasses and a polyhydric alcohol, and mixed by stirring to contain the silicone-based surfactant. Molasses polyol may be used.

This mixing and mixing and stirring are carried out by stirring at a temperature of about room temperature to about 60 ° C. at 200 to 600 rpm for 1 to 48 hours. In addition, insolubles are removed at a rotation speed of 2,000 to 8,000 rpm at 10 to 6 times.
Performed by centrifugation for 0 minutes.

The dehydration from the molasses polyol containing the silicone surfactant thus obtained is carried out at 40 to 0.0.
It is carried out by concentrating under reduced pressure at about 30-60 ° C. under reduced pressure of about 1 Torr.

In this process, molasses polyol foams violently due to rapid decompression in the conventional method and flows out of the system, so that pressure can be reduced only gradually. However, molasses polyol containing a silicone-based surfactant hardly foams. Since it is not recognized, the pressure can be rapidly reduced, and as a result, dehydration can be performed quickly.

The molasses polyol dehydrated as described above can be used as a raw material for producing polyurethane in the same manner as a normal polyol component, and a conventionally known isocyanate component, for example, an aliphatic compound such as hexamethylene diisocyanate. Alicyclic polyisocyanates such as isophorone diisocyanate; aromatics such as tolylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate (MDI), polymeric diphenylmethane diisocyanate, triphenylmethane triisocyanate, and tris (isocyanatephenyl) thiophosphate Polyisocyanate, urethane prepolymer, hexamethylene diisocyanate buret, hexamethylene diisocyanate trimer, Polyurethane can be produced by reacting with a modified product thereof such as sophorone diisocyanate trimer and the like according to a conventional method.

For the production of polyurethane, for example, 25 to 75%, preferably about 35 to 65% of a polyisocyanate component is added to the molasses polyol obtained as described above and mixed, and the mixture is added at 10 to 150 ° C., preferably at 20-120
The reaction can be carried out at a temperature of ° C., at normal pressure or under pressure.

In the production of polyurethane, it is preferable to add a catalyst for the urethanization reaction to the molasses polyol. As such a catalyst, a conventionally known catalyst such as a tin-based catalyst or an amine-based catalyst can be used. .

When a polyurethane is produced by the present invention, a mixture obtained by adding and mixing molasses polyol with polyisocyanate is used as a molding material, molded into a required shape, and then subjected to a urethane-forming reaction to obtain a polyurethane composite having a required shape. It can be a molded article. Further, by adding an appropriate amount of water as a foaming agent to the molasses polyol, a foam molded article can be obtained. The shape of the molded product can be various shapes such as a sheet shape, a plate shape, a column shape, and a container shape.

[0026]

Next, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

Example 1 100 g of molasses (moisture content 19.6%) and polyethylene glycol 200 (PEG 200; average molecular weight 200) 2
00 g was weighed and mixed and stirred with a mixing stirrer for about 1 hour. This is then centrifuged for 20 minutes at 8
Centrifugation was performed at 000 rpm to remove solid residue. After centrifugation, the supernatant is added to a silicone surfactant (NUC
3 g of silicone L-500) was added thereto, and the mixture was concentrated under reduced pressure at a temperature of 50 ° C. and a pressure of 30 Torr for 20 minutes using a rotary evaporator, so that the water content was 2.5%.
Thus, a sugar-tight polyol reduced in amount was obtained.

EXAMPLE 2 100 g of molasses (19.6% water content) and PEG 200
200 g (average molecular weight: 200) and 3 g of a silicone surfactant (NUC silicone L-500) were weighed, and mixed and stirred for about 1 hour with a mixing stirrer. Then, this was centrifuged at 8000 rpm for 20 minutes.
Centrifugation was performed to remove solid residue. The supernatant liquid after the centrifugation was concentrated under reduced pressure at a temperature of 50 ° C. and a pressure of 30 Torr for 20 minutes using a rotary evaporator to obtain a sugar-tight polyol whose water content was reduced to 2.5%.

Example 3 A molasses polyol was prepared in the same manner as in Example 1 except that no silicone surfactant was added. This one is
2.5% moisture content due to foaming by vacuum concentration process
Approximately 40 hours were required to lower the temperature.

Example 4 100 g of molasses (moisture content 19.6%) and 200 of polyethylene glycol 200 (PEG, average molecular weight 200)
g was weighed and mixed and stirred with a mixing stirrer for about 1 hour.
Then, this was centrifuged for 20 minutes at 800
Centrifugation was performed at 0 rpm to remove solid residue. After centrifugation, the supernatant was centrifuged for 1 To using a centrifugal evaporator.
The water was concentrated under reduced pressure at rr for 4 hours to reduce the water content to 1.
A molasses polyol reduced to 5% was obtained.

EXAMPLE 5 To 25 g of the molasses polyol obtained in Example 4 was added 1.1 g of a silicone-based surfactant (NUC Silicone L-5420; manufactured by Nippon Unicar Co., Ltd.) and a tin-based catalyst (di-n-dilaurate). (Butyltin) (11 drops) and stir well.
43 g of crude MDI is added thereto and stirred, and when the foaming starts, the stirring is stopped. After the foaming has proceeded sufficiently, the product is left to stand overnight. Table 1 shows the results of a compression test and a thermal analysis performed on the polyurethane foam (product of the present invention) thus obtained. As a comparative product, a polyurethane foam prepared using polyethylene glycol 200 instead of molasses polyol was used.

[0032]

As is apparent from the results, the polyurethane prepared using the molasses polyol of the present invention has a density,
Although the thermal decomposition temperature and the like are almost the same as the conventional one, the compression elastic modulus and the compressive strength were extremely superior to the conventional one.

Example 6 The biodegradability of the product of the present invention and the comparative product obtained in Example 5 was tested by a soil burial test. As a result, in the comparative product containing no natural product, almost no weight loss was observed in the soil burial test for 4 months, but the product of the present invention prepared from molasses polyol was the same as wood such as cedar and beech. It showed a degree of deterioration. In addition, even when compared with a biodegradability test of a polyurethane using a natural product other than molasses as a raw material, the polyurethane to which molasses was added showed the most excellent degradability.

[0035]

By using the substantially anhydrous molasses polyol of the present invention, the degree of foaming can be controlled, and not only a biodegradable foamed polyurethane having desired physical properties can be obtained, but also a non-foamable polyurethane. , For example, a polyurethane sheet and the like. On the other hand, according to the method for concentrating industrial molasses polyol of the present invention, the concentration step, which conventionally took 30 to 50 hours, can be reduced to only 20 minutes. In addition, molasses polyol obtained by concentration has other properties, such as viscosity and foaming property, which are the same as those of the conventional one, and polyurethane foam prepared by using molasses-polyol dehydrated by the method of the present invention is conventionally used. No difference was found from that prepared using the sugar-tight polyol of Example 1. Therefore, the method of the present invention is extremely excellent as a method for removing water from molasses polyol, and is significant. that's all

Continued on the front page (72) Inventor Ken Kobashigawa 2-23-17 Matsuyama, Naha-shi, Okinawa Inside the Tropical Techno Center Co., Ltd. (72) Inventor Yui Tokashiki 2-23-17 Matsuyama, Naha-shi, Okinawa Tropical Co., Ltd. Examiner at the Techno Center Eika Hashimoto (56) References JP-A-54-112998 (JP, A) JP-A-7-196763 (JP, A) JP-A-6-157799 (JP, A) JP-A 4- 93315 (JP, A) JP-A-6-271635 (JP, A) JP-A-5-186556 (JP, A) JP-A-53-74597 (JP, A) JP-A-53-74573 (JP, A) JP-A-53-74596 (JP, A) JP-A-51-73598 (JP, A) JP-T-58-502151 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C08G 18/00-18/87

Claims (10)

(57) [Claims] 1. A method for dehydrating a polyol composition, comprising adding a silicone-based surfactant to a polyol composition containing molasses and a polyhydric alcohol, and then removing water. 2. The method for dehydrating a polyol composition according to claim 1, wherein the water content in the polyol composition is 3% by weight or less. 3. The method according to claim 2, wherein the polyol composition to be dehydrated is 20 to 50.
3. The method for dehydrating a polyol composition according to claim 1, wherein the polyol composition comprises mol% molasses and 50 to 80% polyhydric alcohol. 4. The method for dehydrating a polyol composition according to claim 3, wherein the polyhydric alcohol is selected from ethylene glycol, glycerin and polyethylene glycol having a molecular weight of 3,000 or less. 5. The method for dehydrating a polyol composition according to claim 1, wherein 0.5 to 5% by weight of a silicone surfactant is added to the polyol composition to be dehydrated. . 6. The method for dehydrating a polyol composition according to claim 1, wherein the silicone-based surfactant is an organic silicone block copolymer. 7. A substantially anhydrous polyol composition for polyurethane containing molasses and a polyhydric alcohol. 8. Molasses of 20-50% by weight, 50-80%
Contains 3% by weight of polyhydric alcohol by weight
A substantially anhydrous polyol composition according to claim 7 wherein: 9. The substantially anhydrous polyol composition for polyurethane according to claim 7, which is for non-foamed polyurethane. 10. A polyol composition for polyurethane comprising molasses, a polyhydric alcohol and a silicone-based surfactant and having a water content of 3% by weight or less.