JP2002201220A - Polyvinyl acetate resin for chewing gum - Google Patents

Abstract

(57) [Summary] [PROBLEMS] Excellent handling properties in the production of gum base,
To provide a polyvinyl acetate resin excellent in safety and hygiene in which the amount of residual vinyl acetate monomer is extremely small. (A) an average particle diameter of 50 to 1000 μm;
A polyvinyl acetate resin having (B) a degree of polymerization of 300 to 1500 and (C) a residual vinyl acetate monomer of 5 ppm or less is constituted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a polyvinyl acetate resin. Particularly, the present invention relates to a polyvinyl acetate resin used when producing chewing gum, and is excellent in handling properties, safety and hygiene.

[0002]

2. Description of the Related Art Conventionally, natural tickle is preferable as a chewing gum base resin, but polyvinyl acetate resin is generally used instead of natural tickle due to its high cost. However, since the polyvinyl acetate resin is produced by polymerizing a vinyl acetate monomer, unreacted vinyl acetate monomer remains in the resin, which is not preferable in terms of safety and hygiene. For this reason, recently, polyvinyl acetate resin with a small residual amount of unreacted vinyl acetate monomer has been used,
Most of the polyvinyl acetate resin for chewing gum is a bulk polymerization of a vinyl acetate monomer (JP-B-39-24714).
No.) or solution polymerization using an alcohol-based solvent as a solvent (Food Additive Official Manual, Hirokawa Shoten, 1st edition, September 10, 1979, B-358 to B-359).

[0003]

However, the polyvinyl acetate resin produced by bulk polymerization or solution polymerization not only requires a large amount of heat energy to remove unreacted vinyl acetate monomer, but also requires a large amount of heat. Was also complicated. In addition, the polyvinyl acetate resin produced by bulk polymerization or solution polymerization has a product form of block-like lump. It is not easy, especially in the case of polyvinyl acetate resin with a high degree of polymerization, it has been devised such as cutting in advance or warming the polyvinyl acetate resin before kneading to reduce the viscosity, There is a problem that the operation is complicated and the handling is inferior.

The inventor of the present invention has conducted intensive studies in order to solve the above-mentioned problems.
The present invention has been completed by obtaining a polyvinyl acetate resin excellent in safety and hygiene.

[0005]

That is, the present invention provides:
(1) (A) a polyvinyl acetate resin having an average particle diameter of 50 to 1000 μm, (B) a degree of polymerization of 300 to 1500, and (C) a residual vinyl acetate monomer having a characteristic of 5 ppm or less,
(2) The polyvinyl acetate resin according to (1), which is used when producing chewing gum.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. The average particle size of the polyvinyl acetate resin of the present invention is 50.
To 1000 μm, more preferably 200 to
400 μm. If it is less than 50 μm, particles are liable to be scattered at the time of kneading in the production of a gum base, and the uniform kneading is inferior. On the other hand, if the thickness is 1000 μm or more, it takes a long time to prepare the gum base, which is not preferable. The degree of polymerization is 300 to 150
0 is preferable, and 600 to 1200 is more preferable. When it is less than 300, the particles are easily fused and it is difficult to maintain the average particle form of the present invention. If the degree of polymerization is 1500 or more, the chewing gum becomes too hard and is not suitable as a polyvinyl acetate resin used for the production of chewing gum. Residual vinyl acetate monomer is 5 pp for safety and hygiene.
m or less is required.

The (A) of the present invention has an average particle diameter of 50 to 1000.
The polyvinyl acetate resin having the properties of μm, (B) a degree of polymerization of 300 to 1500, and (C) a residual vinyl acetate monomer of 5 ppm or less is provided, for example, by the following method.

[0008] A vinyl acetate monomer is polymerized in an aqueous dispersion medium in the presence of a polymerization catalyst, a suspension stabilizer and a polymerization degree regulator, and after the polymerization, the slurry is depressurized to remove unreacted vinyl acetate monomer. You.

Examples of the polymerization catalyst used in the polymerization include an azo polymerization catalyst represented by azoisobutyronitrile and an organic peroxide polymerization catalyst represented by lauroyl peroxide. Organic peroxide catalysts are preferred from the viewpoint of quality such as coloring of the polymerized polyvinyl acetate resin. Any suspension stabilizer can be used as long as it is a suspension stabilizer usually used for suspension polymerization of a vinyl monomer having an ethylenic double bond, for example, a polyvinyl alcohol resin, a cellulose ether represented by hydroxypropylmethylcellulose. And polyvinylpyrrolidone, and these can be used in combination.

As the polymerization degree regulator, there are aldehydes represented by acetaldehyde, ketones represented by acetone, mercaptans represented by 2-mercapto alcohol, alcohols represented by isopropyl alcohol, and the like. Further, an alcohol solvent may be used in combination to obtain the present invention. Examples of the alcohol-based solvent include methyl alcohol, ethyl alcohol, and isopropyl alcohol. Among them, ethyl alcohol is particularly preferable in consideration of use in the production of chewing gum.

[0011]

Hereinafter, the present invention will be described with reference to examples.
The present invention is not limited to these examples.
Hereinafter, “parts” means parts by weight.

Example 1 Pure water 2 was placed in a 200-liter autoclave equipped with a stirrer.
70 parts, 100 parts of vinyl acetate monomer, 0.1 part of partially saponified polyvinyl alcohol, 0.3 part of lauroyl peroxide, and 1.2 parts of normal butyraldehyde were charged and polymerized at a polymerization temperature of 62 ° C. for 7 hours. Next, the pressure was reduced at a temperature of 65 ° C. while stirring the slurry to remove unreacted vinyl acetate monomer. Next, the slurry was dehydrated and dried to obtain a particulate polyvinyl acetate resin. The resulting polyvinyl acetate resin had an average particle size of 245 μm, a degree of polymerization of 820, and a residual vinyl acetate monomer of less than 3 ppm. To 100 parts of this polyvinyl acetate resin, 30 parts of microcrystalline wax, 30 parts of polyisobutylene, and 8 parts of calcium carbonate were put into a paddle type 10 liter kneader, and kneaded under the conditions of a jacket temperature of 110 ° C. and a rotation speed of 100 rpm. . Table 1 shows the evaluation method as a gum base and the results.
Shown in

[0013]

[Table 1]

The analysis method and the evaluation method are as follows. 1. Analysis method Degree of polymerization Average particle diameter according to JIS K6725 "Testing method for polyvinyl acetate" Classify using a standard tap sieve with a low tap sieve shaker, and use a particle diameter of 50% by weight under the sieve. Residual vinegar bimonomer amount Same as the official edition of Food Additives, Seventh Edition. 2. Evaluation method of chewing gum base Compounding 100 parts of vinyl acetate resin 30 parts of microcrystalline wax 30 parts of polyisobutene 8 parts of kneading 8 parts of kneading Kneading at a jacket temperature of 110 ° C. and a rotation speed of 100 rpm with a 10 liter kneader. Evaluation items and evaluation methods: Details are shown in Table 2.

[0015]

[Table 2]

<Judgment> ◎ Particularly good ○ Good △ Normal × Bad ×× Particularly bad

Example 2 Example 1 was repeated except that 0.7 parts of normal butyraldehyde and 0.03 parts of partially saponified polyvinyl alcohol were used.
The same was done. The average particle diameter of the obtained polyvinyl acetate was 790 μm, the degree of polymerization was 1310, and the residual vinyl acetate monomer was less than 3 ppm. This was evaluated as a gum base in the same manner as in Example 1. Table 1 shows the results.

Example 3 The procedure of Example 1 was repeated except that normal butyraldehyde was changed to 4.0 parts, partially saponified polyvinyl alcohol was changed to 0.15 parts, and lauroyl peroxide was changed to 0.4 parts. The average particle size of the obtained polyvinyl acetate is 255 μm.
m, degree of polymerization 310, residual vinyl acetate monomer 3 ppm
Was less than. This was evaluated as a gum base in the same manner as in Example 1. Table 1 shows the results.

Example 4 The procedure of Example 1 was repeated except that the partially saponified polyvinyl alcohol was changed to 0.8 part. The average particle diameter of the obtained polyvinyl acetate was 55 μm, the degree of polymerization was 810, and the amount of residual vinyl acetate monomer was less than 3 ppm. Example 1
The evaluation as a gum base was performed in the same manner as described above. Table 1 shows the results.

Comparative Example 1 The procedure of Example 1 was repeated, except that the partially saponified polyvinyl alcohol was changed to 1.5 parts. The average particle diameter of the obtained polyvinyl acetate was 25 μm, the degree of polymerization was 800, and the residual vinyl acetate monomer was less than 3 ppm. Example 1
The evaluation as a gum base was performed in the same manner as described above. Table 1 shows the results.

Comparative Example 2 The procedure of Example 1 was repeated, except that 6.0 parts of normal butyraldehyde, 0.2 part of partially saponified polyvinyl alcohol, and 0.5 part of lauroyl peroxide were used. In the step of dehydrating and drying the slurry, the particles adhered to each other to form a lump. The polymerization degree of the obtained polyvinyl acetate resin is 21.
0, the residual vinyl acetate monomer was less than 3 ppm.
This was evaluated as a gum base in the same manner as in Example 1. Table 1 shows the results.

Comparative Example 3 Except that normal butyraldehyde was changed to 0.4 part,
Performed in the same manner as in Example 1. The average particle diameter of the obtained polyvinyl acetate was 240 μm, the degree of polymerization was 1810, and the amount of the residual vinyl acetate monomer was less than 3 ppm. This was evaluated as a gum base in the same manner as in Example 1. Table 1 shows the results.

Comparative Example 4 In a 200-liter autoclave equipped with a stirrer, 370 parts of vinyl acetate monomer and lauroyl peroxide 0.1% were added.
2 parts and 2.5 parts of normal butyraldehyde were charged and bulk polymerization was performed at a polymerization temperature of 62 ° C. for 7 hours. Next, the pressure was reduced at a temperature of 65 ° C. while stirring the polymer to remove unreacted vinyl acetate monomer. Next, the bulk polymer was taken out into a stainless steel container and dried to obtain a bulk polyvinyl acetate resin.
The polymerization degree of the obtained polyvinyl acetate resin was 790, and the residual vinyl acetate monomer was 108 ppm. This was evaluated as a gum base in the same manner as in Example 1. Table 1 shows the results.

Comparative Example 5 A 200-liter autoclave equipped with a stirrer was charged with 250 parts of vinyl acetate monomer, 120 parts of ethyl alcohol, and 0.4 part of lauroyl peroxide.
Solution polymerization was carried out at 2 ° C. for 7 hours. Next, the pressure of the polymer was reduced at 65 ° C. while stirring, to remove unreacted vinyl acetate monomer. Next, the solution polymer was taken out into a stainless steel container and dried to obtain a lump polyvinyl acetate resin. The polymerization degree of the obtained polyvinyl acetate resin was 1320, and the residual vinyl acetate monomer was 52 ppm. This was evaluated as a gum base in the same manner as in Example 1. Table 1 shows the results.

[0025]

As described above, the polyvinyl acetate resin of the present invention has excellent handling properties in the production of a gum base, and has very little residual vinyl acetate monomer.
And excellent hygiene.

Claims (2)

[Claims] (A) an average particle diameter of 50 to 1000 μm,
(B) A polyvinyl acetate resin having a degree of polymerization of 300 to 1500 and (C) a residual vinyl acetate monomer of 5 ppm or less. 2. The polyvinyl acetate resin according to claim 1, which is used for producing chewing gum.