JPH0912588A - Sugar ester polyol, its production and biodegradable polyurethane utilizing the same - Google Patents

Abstract

PURPOSE: To produce a new ester polyol, rapidly degradable in the natural world, excellent in biodegradability and useful as a raw material, etc., for producing a polyurethane for agriculture- and horticulture-related materials, etc., by adding a specific cyclic lactone to sugars. CONSTITUTION: This new ester polyol of formula I R is a saccharide skeleton; A is an alkylene; n is the total number of hydroxyl groups in the sugar; m is the number of hydroxyl groups to be esterified in the sugar; [n-m] is the number of hydroxyl groups remaining without being esterified and a number within the range of 0 to [n-1]; the product of (l) and m is the number of the cyclic lactone added to the hydroxyl groups in the sugar}. The ester polyol is rapidly degrading in the natural world, excellent in biodegradability and widely utilizable not only as agriculture- and horticulture-related materials but also as household and industria1 uses, etc. The compound is obtained by reacting sugars of formula II (e.g. glucose) with a cyclic lactone of formula III (e.g. ε-caprolactone).

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a sugar ester polyol produced from a saccharide as a raw material and a method for producing the same.
More specifically, the present invention relates to a sugar ester polyol that is a raw material for polyurethane, which is easily decomposed by microorganisms in the natural environment after use, a method for producing the same, and a biodegradable polyurethane prepared using the same.

[0002]

2. Description of the Related Art In recent years, attempts have been made widely to impart synthetic degradability to synthetic polymers such as plastics. Polyurethane prepared by reacting a polyol component and an isocyanate component is also biodegradable. Various attempts have been made to give

For example, Japanese Patent Publication No. 58-56605 discloses that
A hydrophilic urethane foam obtained by adding a microbial powdery organic filler to a hydrophilic urethane foam, and Japanese Patent Laid-Open No. 63-284232 discloses a vegetable fine fiber or a vegetable powder containing an ester group. There is disclosed a sheet or a molded article which is decomposed in the natural world, which is combined with a urethane resin obtained by the reaction of a polyol and an organic polyisocyanate.

In any of the above inventions, the presence of additives such as natural organic substances and vegetable fibers is essential, and it is basically not due to the decomposability of the polyurethane itself but due to the degradability of the additives.

By the way, recently, unlike the above-mentioned method, a method has been developed in which the molasses is added to the polyol component to make the polyurethane itself biodegradable (Japanese Patent Application No. 3-33402, etc.). The polyurethane obtained by this technology does not use plant fine fibers, etc., and therefore has the same appearance as that of ordinary ones but satisfactory biodegradability, but the molasses used is a natural product. However, it was difficult to control the foaming of polyurethane depending on the conditions.

[0006]

Although it has been possible to impart almost satisfactory biodegradability to the polyurethane itself by utilizing the above molasses, it is required to eliminate the above-mentioned processing problems. Therefore, an object of the present invention is to provide a technique for producing a biodegradable polyurethane that solves this problem.

[0007]

[Means for Solving the Problems] As a result of research on the possibility of using saccharides as a polyol for producing polyurethane, the present inventors have found that biodegradability is improved by modifying the hydroxyl groups of saccharides with ester groups. The present invention has been completed by finding that a polyol having excellent performance can be obtained as a raw material for polyurethane.

That is, the present invention provides the following formula (I):

Embedded image (In the formula, R represents a sugar skeleton, A represents an alkylene group, n represents the total number of hydroxyl groups in the sugar, m represents the number of hydroxyl groups to be esterified in the sugar, and nm is not esterified. The number of hydroxyl groups in the remaining sugar represents a number in the range of 0 to n-1, and the product of 1 and m represents the number of cyclic lactone added to the hydroxyl group of the sugar). It is provided.

The sugar ester polyol of the present invention is produced by adding the cyclic lactone represented by the formula (III) to the saccharide represented by the formula (II) to give an ester according to the following formula.

[Chemical 6] (Wherein R, A, m, n and l have the above-mentioned meanings)

Examples of the saccharide (II) include monosaccharides such as glucose, fructose, mannose, arabinose, xylose and galactose, disaccharides such as sucrose, cellobiose and maltose, oligosaccharides such as cellotriose, cellulose, starch and glycogen. , Caronin, laminaran, dextran, inulin, levan,
Mannan, xylan, pectic acid, alginic acid, chitin, guaran, heparin, chondroitin sulfate, hyaluronic acid, methkit gum, gatch gum, gum arabic,
Polysaccharides such as plant mucilage and bacterial polysaccharides are used.

Instead of these, molasses which is a mixture thereof may be used. Molasses is obtained from sugar cane, sugar beet, etc., and may be refined molasses, ice molasses, or molasses obtained after sugar production, but molasses is advantageous from the economical point of view. is there.

On the other hand, as the cyclic lactone (III), for example, methyl ε-caprolactone, ε-caprolactone, β-propiolactone, β-butyrolactone, δ-
Cyclic lactones such as valerolactone, and compounds having an aliphatic or aromatic substituent therefor can be preferably used. In addition, these cyclic lactones are 2
More than one species can be used in combination.

The above saccharide (II) and cyclic lactone (III)
The number of esterified hydroxyl groups in the sugar is m
Generally, 1 to 100 mol of cyclic lactone (III) is used for 1 mol of hydroxyl group of saccharide (II), though it depends on
Can be done using.

The reaction is generally carried out in the presence or absence of a solvent, for example, a metal alcoholate such as tin, lead, manganese or aluminum, a metal carboxylate, a catalyst such as an alkyl metal or a chelate metal, more specifically, a catalyst. , For example, di-n-butyltin dilaurate, tin di (2-ethylhexanoate),
A catalyst such as titanium tetraisopropoxide or aluminum triisopropoxide may be used at a temperature of room temperature to 180 ° C. for about 1 to 24 hours.

In the above reaction, saccharide (II) and polyhydric alcohol may be used in combination and reacted with cyclic lactone (III).

The sugar ester polyol of the present invention thus obtained can be used as a raw material for polyurethane production, in the same manner as a usual polyol component. For example,
A biodegradable polyurethane can be produced by optionally mixing the sugar ester polyol of the present invention with a conventionally known polyol component and reacting it with a known isocyanate component.

For example, the polyisocyanate component is added to and mixed with the sugar ester polyol obtained as described above or a mixture of the sugar ester polyol and the known polyol component, and 10 to 1 is added.
The reaction can be carried out at a temperature of 50 ° C., preferably 20 to 120 ° C., atmospheric pressure or pressure.

The proportion of the polyisocyanate component used in the production of polyurethane is 25 to 75%, preferably 35 to 65%.

The isocyanate component used is
There is no particular limitation, and examples thereof include aliphatic polyisocyanates, alicyclic polyisocyanates, aromatic polyisocyanates, and modified products thereof.

Of these, examples of the aliphatic polyisocyanate include hexamethylene diisocyanate, and examples of the alicyclic polyisocyanate include isophorone diisocyanate.

Examples of the aromatic polyisocyanate include tolylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate (MDI), polymeric diphenylmethane diisocyanate, triphenylmethane triisocyanate, tris (isocyanatophenyl) thiophosphate and the like. .

Further, examples of the modified polyisocyanate include urethane prepolymer, hexamethylene diisocyanate burette, hexamethylene diisocyanate trimer, and isophorone diisocyanate trimer.

Further, in the production of polyurethane, it is preferable to add a catalyst for the urethanization reaction to the sugar ester polyol, and as such a catalyst, a conventionally known one such as tin type or amine type is used. it can.

When a polyurethane is produced according to the present invention, a mixture obtained by adding and mixing a polyisocyanate to a sugar ester polyol is used as a molding material, and the mixture is molded into a desired shape and then subjected to a urethanization reaction to obtain a polyurethane having a desired shape. It can be a composite molded article.
Further, by adding an appropriate amount of water as a foaming agent to the sugar ester polyol, a foamed 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.

[0025]

The polyurethane prepared by using the sugar ester polyol of the present invention has high strength and biodegradability as shown in Examples below, because of the action of the sugar component in the sugar ester polyol. . That is, since sugar acts as a hard segment in polyurethane, strength can be increased. In the biodegradable polyurethane of the present invention, the sugar component incorporated therein is preferentially subjected to the action of microorganisms and rapidly decomposes.

[0026]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.

Example 1 Glucose 5 g was weighed into 5 g of ethylene glycol and heated to dissolve. The obtained solution 5.84 g
0.02 g of di-n-butyltin dilaurate was added to
A mixture of 80 g of ε-caprolactone and 0.05 g of di-n-butyltin dilaurate was added dropwise thereto at 150 ° C over 1 hour and 30 minutes. After the dropping, the reaction was further continued at 150 ° C. for 22 hours to prepare a glucose-ethylene glycol-based sugar ester polyol.

The sugar ester polyol obtained had a number average molecular weight of 2,018, a weight average molecular weight of 4,965, a softening point of 35.6 ° C. and a hydroxyl value of 60.84 mg KOH / g.

Further, the following absorption was confirmed from the infrared absorption spectrum. Ester: 1726 cm ^-1 , 1244 cm ^-1 Ether: 1192 cm ^-1 Alcohol: 3437 cm ^-1 , 1047 cm ^-1 Methylene: 2946 cm ^-1 , 2866 cm ^-1 , 733
cm ^-1

Example 2 5.84 g of a solution prepared by dissolving fructose in place of glucose in ethylene glycol in the same amount as in Example 1.
A fructose-ethylene glycol-based sugar ester polyol was prepared in the same manner as in Example 1.

The sugar ester polyol thus obtained had a number average molecular weight of 3,061, a weight average molecular weight of 5,413, a softening point of 34.70 ° C. and a hydroxyl value of 71.97 mgKOH / g.
Met.

Further, the following absorption was confirmed from the infrared absorption spectrum. Ester: 1728 cm ^-1 , 1244 cm ^-1 Ether: 1190 cm ^-1 Alcohol: 3444 cm ^-1 , 1048 cm ^-1 Methylene: 2946 cm ^-1 , 2868 cm ^-1 , 732
cm ^-1

Example 3 In Example 1, 6.30 g of a solution prepared by dissolving sucrose instead of glucose in ethylene glycol in the same amount.
A sucrose-ethylene glycol sugar ester polyol was prepared in the same manner as in Example 1.

The obtained sugar ester polyol had a number average molecular weight of 1,762, a weight average molecular weight of 3,935, a softening point of 33.7 ° C. and a hydroxyl value of 73.97 mgKOH / g.

Further, the following absorption was confirmed from the infrared absorption spectrum. Ester: 1726 cm ^-1 , 1244 cm ^-1 Ether: 1192 cm ^-1 Alcohol: 3437 cm ^-1 , 1047 cm ^-1 Methylene: 2946 cm ^-1 , 2866 cm ^-1 , 733
cm ^-1

Example 4 80 g of molasses was weighed in 20 g of ethylene glycol, and mixed and stirred for about 2 hours with a mixing stirrer. Then
The solid residue was removed by centrifugation at 8000 rpm for 20 minutes using a centrifuge. After removing water from 14.74 g of the obtained mixture (water content: 23%),
02 g of di-n-butyltin dilaurate are added, to which 80 g of a mixture of ε-caprolactone and 0.05 g of di-n-butyltin dilaurate are added at 150 ° C. for 3 hours for 1 hour.
It was added dropwise over 0 minutes. After dripping, it is further 22
The reaction was continued for a time to prepare a molasses-ethylene glycol-based sugar ester polyol.

The resulting sugar ester polyol had a number average molecular weight of 1,845, a weight average molecular weight of 4,503, a softening point of 34.1 ° C. and a hydroxyl value of 77.88 mgKOH / g.

Further, the following absorption was confirmed from the infrared absorption spectrum. Ester: 1726 cm ^-1 , 1246 cm ^-1 Ether: 1194 cm ^-1 Alcohol: 3437 cm ^-1 , 1047 cm ^-1 Methylene: 2944 cm ^-1 , 2866 cm ^-1 , 733
cm ^-1

Example 5 To 7.48 g of sucrose, a mixture of 80 g of ε-caprolactone and 0.07 g of di-n-butyltin dilaurate was added dropwise at 150 ° C. over 1 hour and 30 minutes. After dripping,
The reaction was continued at 150 ° C for 22 hours, and sucrose-
A sugar ester polyol was prepared.

The following absorption was observed in the infrared absorption spectrum of the obtained sugar ester polyol.

Ester: 1726 cm ^-1 , 1244 cm ^-1 Ether: 1192 cm ^-1 Alcohol: 3437 cm ^-1 , 1047 cm ^-1 Methylene: 2946 cm ^-1 , 2866 cm ^-1 , 733
cm ^-1

Example 6 1 g of cellulose was dissolved in 50 ml of hexamethylphosphoamide in which 4 g of lithium chloride was dissolved, and a small amount of dibutyltin dilaurate was added to the solution to obtain a solution containing a small amount of dibutyltin dilaurate. ε-caprolactone
5 g was added dropwise at 170 ° C., and then reacted for 2 hours. 50 ml of water was added to the obtained solution, which was placed in a cellophane tube for desalting, and then water in the tube contents was distilled off under reduced pressure. In the infrared absorption spectrum of the obtained compound, absorption at 1730 cm ^-1 based on an ester bond was observed.

Example 7 30 g of the sugar ester polyol obtained in Example 4 was heated and melted, and then deaerated in a vacuum. 5.64 there
g of crude diphenylmethane diisocyanate (M
DI) was added, mixed and stirred slowly, and then degassed.

The obtained mixture was heated at 110 ° C. and 200 kgf.
/ Cm ² was pressed for 2 hours to prepare a polyurethane sheet. The glass transition temperature of this polyurethane sheet is −
The temperature was 49.6 ° C and the thermal decomposition temperature was 337.4 ° C.

Example 8 8.0 g of the sugar ester polyol obtained in Example 3 was melted, weighed into 12.0 g of commercially available polycaprolactone (average molecular weight 550), mixed and stirred slowly, and in a vacuum. Degassed. 7.33 g of MDI was added thereto, and the mixture was slowly mixed and stirred, and then degassed.

The obtained mixture was heated at 110 ° C. and 200 kgf.
/ Cm ² was pressed for 2 hours to prepare a polyurethane sheet. The glass transition temperature of this polyurethane sheet is −
The temperature was 19.1 ° C and the thermal decomposition temperature was 333.7 ° C.

Example 9 50 g of the sugar ester polyol obtained in Example 4 was added to 50 g.
Commercially available polycaprolactone (average molecular weight 2000), water 3.0 g, foam stabilizer (NUC Silicone L-520; Nippon Unicar Co., Ltd.) 2.7 g, tin catalyst (dilauric acid di-). 0.6 g of n-butyltin) and 0.6 g of amine-based catalyst (diazabicyclooctane) are added, and the mixture is stirred well. 73.4 g of MDI was added thereto and stirred, and the stirring was stopped when foaming started. After the foaming proceeded sufficiently, the product was further left overnight to prepare a polyurethane foam.

[0048]

EFFECT OF THE INVENTION The polyurethane prepared using the sugar ester polyol of the present invention has excellent biodegradability and is rapidly decomposed in nature. Therefore, the biodegradable polyurethane of the present invention can be widely used not only as a material for agricultural and horticultural purposes but also for household use, industrial use, etc. as it returns to nature after it is no longer needed. that's all

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Teruya Teruya, 5-1, Kyushuzaki, Gushikawa-shi, Okinawa Prefecture Tropical Techno Center Co., Ltd. (72) Ken Kobashigawa, 5-1 Kushizaki, Kushizaki, Gushikawa-shi, Okinawa Prefecture In the Tropical Techno Center (72) Inventor Yusho Tokashiki 5-1 Kushizaki, Gushikawa City, Okinawa Prefecture Tropical Techno Center Co., Ltd.

Claims (7)

[Claims] 1. The following formula (I): (In the formula, R represents a sugar skeleton, A represents an alkylene group, n represents the total number of hydroxyl groups in the sugar, m represents the number of hydroxyl groups to be esterified in the sugar, and nm is not esterified. The number of hydroxyl groups in the remaining sugar, which is a number in the range of 0 to n-1, and the product of 1 and m represents the number of cyclic lactones added to the hydroxyl groups of the sugar). 2. The sugar ester polyol according to claim 1, wherein the saccharide is selected from monosaccharides, disaccharides, oligosaccharides or polysaccharides. 3. The cyclic lactone is methyl ε-caprolactone, ε-caprolactone, β-propiolactone,
The sugar ester polyol according to claim 1, which is one or more of β-butyrolactone, δ-valerolactone or a compound having an aliphatic or aromatic substituent on them. 4. The following formula (II): (Wherein R represents a sugar skeleton and n represents the total number of hydroxyl groups in the sugar) and a sugar represented by the following formula (III): A cyclic lactone represented by the formula (wherein A represents an alkylene group) is added, and the following formula (I): (In the formula, R, A, and n have the above-described meanings, m represents the number of hydroxyl groups in the sugar that are esterified, and nm is the number of hydroxyl groups in the sugar that is not esterified and remains, 0-n-
A method for producing a sugar ester polyol represented by the formula (1), and the product of 1 and m represents the number of cyclic lactones added to the sugar hydroxyl group. 5. A biodegradable polyurethane obtained by reacting the sugar ester polyol according to claim 1 with isocyanates. 6. The biodegradable polyurethane according to claim 5, wherein the saccharide is selected from monosaccharides, disaccharides, oligosaccharides and polysaccharides. 7. The cyclic lactone is methyl ε-caprolactone, ε-caprolactone, β-propiolactone,
The biodegradable polyurethane according to claim 5, which is one or more of β-butyrolactone, δ-valerolactone or a compound having an aliphatic or aromatic substituent on them.