JPS59100138A - Production of dialkyltin mercaptocarboxylate polymer - Google Patents

Abstract

PURPOSE:To produce the titled polymer useful as a stabilizer for thermoplastic resins easily in high yields, by reacting a dialkyltin oxide with a mercaptocarboxylic acid in the presence of a 1-3C aliphatic manoalcohol. CONSTITUTION:1mol of a dialkyltin oxide (e.g., di-n-butyltin oxide or di-n-octyltin oxide) is reacted with about 0.8-1mol of a mercaptocarboxylic acid (e.g., mercaptoacetic acid or beta-mercaptopropionic acid) in the presence of about 10- 90wt% 1-2C aliphatic monoalcohol (e.g., methanol or ethanol). In this way, it becomes possible to produce a polymer having small and uniform particle diameters, being freed from block formation, and necessitating no grinding. The produced polymer is separated from the solvent and dried to obtain the titled polymer.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improved method for making dialkyltin mercaptocarboxylic root polymers, and further! 1'(: Specifically, improvement of polymers useful as stabilizers for various thermoplastic resins including polyvinyl chloride, characterized by the reaction being carried out in the presence of specific alcohols. Regarding manufacturing methods.

When vinyl chloride resin is heat-molded, it tends to undergo thermal deterioration mainly due to dehydrochlorination reactions, and as a result, processed resin products tend to suffer from drawbacks such as thermal discoloration or deterioration of mechanical properties.

As an effective means to overcome these drawbacks, a di-alkyltin mercaptocargyphosylate polymer is used as a stabilizer.

The method for preparing the polymer includes, for example, reacting dialkyltin oxide and mecaptocarboxylic acid at a temperature equal to or higher than the melting point of the resulting polymer, and then cooling and pulverizing the resulting product. Melting: For example, dialkyltin oxide is added to a system consisting of mercaptocarboxylic acid □ and acetone containing 1'0% water by weight, and the mixture is reacted under reflux.
・There is a melting method that involves cooling, filtering, and drying, but first of all, when using the melting method like the first method, the viscosity of the reaction system becomes extremely high, so special equipment is required. Moreover, there is a large gap when taking out the block, and it is extremely difficult to crush the cooled block.
On the other hand, when using the latter melting method, there are also drawbacks such as the formation of blocks, which makes stirring extremely difficult, making it undesirable. The current situation is that there is no satisfactory method for preparing the polymer.・However, as a result of intensive research in view of these actual circumstances, the inventors of the present invention found that in the presence of specific alcohols, the respective reaction components of dialkyl tin oxide and mercapto carboxylic acid were allowed to react at temperatures above the boiling point of the solvent. By,
Since it is possible to obtain a polymer having small and uniform particles without the generation of blocks or pulverization, the polymer particles and the solvent are simply separated, and the particles are Just dry it for 1°, and then 9
We have now completed the present invention by discovering an extremely useful production method that allows the desired dialkyltin mercaptocarboxylate polymer to be obtained at a commercial yield of 7%.

That is, the present invention provides dialkyltin mercaptocarboxylic acid, which is characterized by reacting dialkyltin oxide and mercapto carboxylic acid in the presence of an aliphatic alcohol having 1 to 3 carbon atoms by a conventional method. It provides an M method for rate polymers.

Here, the above-mentioned aliphatic-hydric alcohols refer to methanol, ethanol, n-propatool, and isopropatool, but in particular, yield and dryness]
- Methanol or ethanol is preferred from the viewpoint of moderation.

These alcohols may be used alone or in combination. In addition, when performing a reaction using such alcohols, the alcohol content to be recovered will include water as a by-product, but the recovered alcohol content containing this water will be used as is for the next reaction. It is possible,
There is no problem in doing so.

The amount of alcohol present in the reaction system is:
Usually 10-90i! [The range is 30 to 601 TL (1% is preferred, especially when considering the stirring state of the reaction system, productivity, cost, etc.).

By the way, when using alcohols having 4 or more carbon atoms, the 1-1 polymer which is the reaction product is dissolved in the alcohol, which results in a decrease in the yield of the desired polymer itself. It may be difficult to separate the target polymer obtained in powder form from this alcohol, and furthermore, when the powdered polymer is dried, the alcohol may dissolve into the powder. This will also lower the melting point of the powder, but if you increase the drying temperature to avoid this, it will become dry, so it cannot be raised in the end, and in addition, the boiling point of the alcohol itself is high. Therefore, the drying process at a low temperature requires an extremely long time, which causes various troubles such as the necessity of drying process under a high vacuum. Therefore, the use of such relatively high-grade alcohols is not preferred since it would deviate from the purpose of the present invention.

On the other hand, the dialkyltin oxide described above has 1 to 1 carbon atoms.
It refers to a compound having an alkyl W of 18,
Among these, representative ones include dimedyl tin oxide, diethyl 6-oxide, di-n-]thyl-6-easy oxide, di-2-ethyl tin oxide, and di-2-ethylhexyl tin oxide. These include J, whether used alone or in combination.
Of course, preferred are 5d-11-butyltin oxide and 1-octyltin oxide.

Furthermore, monoalkyltin oxides such as monomethyltin oxa-ide, mono-11-bunaltin oxide:i: or mono-n-octyltin oxide can be used in combination with these dialkyltin oxides.

In addition, typical examples of the above-mentioned mercapto carboxylic acids include mercaptoacetic acid, α-mercaptopropionic acid, and β-mercaptopropionic acid; Among them, β-mercapto butylcopionic acid is particularly preferred. Of course, such carboxylic acids may be used alone or in combination.

The ratio of dialkyl tin oxide and mercapto carboxylic acid used is 0.8 to 1.1 mol, preferably 0.90 to 1.1 mol, per 1 mol of dialkyl tin oxide.
A range of 1.05 moles is suitable.

The dialkyltin mercap] carboxylate polymer thus obtained is a homopolymer or copolymer of vinyl chloride or vinylidene chloride, an acrylonitrile-styrene copolymer, an ABS resin or a M 13 SI.
I li! It is particularly useful as a stabilizer for various thermoplastic resins such as 't.

Here, the copolymer of vinyl chloride or (vinylidene tetrachloride) refers to a copolymer obtained by copolymerizing vinyl chloride or vinylidene chloride with other unsaturated monomers. Typical ethylenically unsaturated monomers include acrylic acid, ethyl acrylate, acrylonitrile, styrene, vinyl acetate, maleic acid,
Examples include mal/ic acid esters, nieren or zoropyrene.

Next, the present invention will be explained in detail with reference to Examples, Comparative Examples, Application Examples, and Comparative Application Examples. All weights and percentages are by weight unless otherwise specified.

Example 1 27! 705 parts of methanol and Mercap in a four-round flask! ...109 parts of propionic acid were charged and mixed with stirring for 5 minutes, and the acid value of the system was 75 when 1 g was taken from the thread and measured.

Next, 361 parts of di-ri-octyltin oxide was added thereto and reacted at 35°C for 6 hours.
After cooling to 0° C., the solvent and the powder were separated using a Nutsche.

Next, the outside of the powder was dried in a dryer at 60°C for 5 hours, and the yield of the target polymer in powder form was 460 parts, which was -t 11'(1' 8 .5
%Met.

Moreover, the melting point of this powdered polymer was 90°C.

On the other hand, the amount of solvent recovered was 424 parts, and the recovery rate was also 60.
%, and the acid value of the solvent was 5.0.

Example 2 A 1 g four-loaf flask was poured into Example 1. Recover Al.

358 parts of Kohl and 1 part of β-mercapto propionic acid
06 parts and stirred and mixed for 5 minutes, and from this system 1
The acid value measured by g sampling was 129.5. Hereafter, instead of di-n-octyltin oxide, 2
The same operation as in Example 1 was repeated except that 49 parts of di-n-butyltin oxide was used, and the yield of the target polymer in powder form was 332 parts.
The yield was 98.5%.

Moreover, the melting point of this powdered polymer was 120°C.

On the other hand, the solvent content was 233 parts, the recovery rate was high at 65%, and the acid value of the solvent content was 4.3.

Example 3 Into the same reaction vessel as in Example 2, 400 parts of ethanol and 96 parts of β-mercaptopropionic acid were charged, stirred and mixed for 5 minutes, and the acid value of the system measured was 110.
It was ℃.

Next, 249 parts of di-n-butyltin oxide was charged into the reactor through a 6-molecular mesh wire mesh, reacted at 70°C for 3 hours, cooled to 30°C, and separated into the solvent and powder using a nusoche. .

The yield of the powdered polymer obtained here was 325 parts, the yield was 98.8%, and the melting point of the polymer powder was 1.
On the other hand, the yield of the solvent was 280 parts, the recovery rate was as high as 70%, and the acid value of this solvent was 2.
．． It was 0.

Comparative Example 1 In a container similar to Example 2, 106 parts of β-norcapto propionic acid was first charged and the temperature was raised to 100°C.
While adding another 249 parts by dividing the temperature to 125°C.
After 2 hours of reaction, the reaction system showed extremely high viscosity.
It became difficult to keep mixing evenly, so
The reaction product was taken out from the container. .

The yield of this reaction product was 236 parts (yield -70
%), and its melting point was 118°C. The reason for the extremely low yield in each of the above-mentioned examples of the present invention is that the reaction product is highly viscous, so the inside surface of the container (vessel wall)
This is thought to be due to the fact that the reaction product adheres to the surface, resulting in a larger gap 3 at the time of removal.

Moreover, such a reaction product is initially in a liquid state even if it has a high viscosity when taken out, but when it is left at 5'C for 2 days, it becomes a hard solid and can no longer be used as an additive. The reactant obtained here is not preferred, since it is not possible and therefore trituration is required.

Comparative Example 2 In a container similar to Example 1, 123 parts of β-mercapto.
362 of propionic acid and acetone containing 10% water.
8 parts, stir and mix, raise the temperature to 55'C, and then
When 26 parts of di-n-butyltin oxide was added, a precipitate formed in the lower layer of the reaction system, and the entire system gradually became cake-like, making stirring no longer possible.

After the reaction product was taken out of the container and dried, the melting point of the precipitate was measured and found to be 90°C.

This example produces a rice cake-like precipitate and is therefore unsuitable for industrial production unless special equipment is used.

Application Examples 1 to 3 and Comparative Application Example 1.2 Using each of the polymers obtained in Examples 1 to 3 and Comparative Example 1.2, separate formulations were obtained according to the following formulation examples,
Next, each blend was kneaded for 5 minutes using an 8-inch roll at 165°C to produce a sheet with a thickness of 0.5 gm.

Vinyl chloride resin (p=xoso) 100 parts DOP
50 〃Polymer 2'' The various sheets thus obtained were tested with vinyl chloride (1).In order to evaluate the quality as a stabilizer for resins, each sheet was placed in a gear type aging tester and tested at 200 We conducted a test to confirm the effect of thermal stability at °C.The results are summarized in
As shown in the table, the numerical values in the table indicate the degree of thermal stability, and are based on the following criteria.

r I J ------One color r 4.1--
---One yellowish brown r 2 J -----Itteki yellow
! -5j -------Ichibro color r 3 J -------
pale yellow

Claims (1)

[Claims] A method for producing a dialkyltin mercaptocarboxylate 1-polymer, which comprises reacting a dialkyltin oxide with a mercaptocarboxylic acid in the presence of an aliphatic alcohol having 1 to 3' carbon atoms.