JPS6147866B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a stabilizer for improving the thermal stability of chlorine-containing resins. More specifically, the polyhydroxy mixed ester reaction product is produced by mixed partial esterification of pentaerythritol or pentaerythritol dehydration condensation polyols with a dibasic acid or higher polybasic acid and a long chain fatty acid (C ₈ - C ₂₄ ) or a derivative thereof. The present invention relates to stabilizers for chlorine-containing resins containing substances. Chlorine-containing resins, especially polyvinyl chloride resins,
It is well known that it is unstable to heat and light, and is colored and deteriorated by heat during processing. To compensate for this drawback, stabilizers such as lead-based, cadmium-based, tin-based, and zinc-based stabilizers have been developed and used. However, recently, environmental and sanitary pollution caused by heavy metals has become a problem, and the use of highly effective stabilizers such as lead-based and cadmium-based stabilizers has been restricted or regulated. Currently, stabilizers for chlorine-containing resins are shifting from the aforementioned lead-based and cadmium-based stabilizers to calcium-zinc-based and barium-zinc-based stabilizers, which are attracting attention as non-toxic compounds. These non-toxic stabilizers are inherently less effective. That is, these have the disadvantage that their heat resistance is considerably inferior to lead-based or cadmium-based stabilizers.
Various studies have been made to improve this, but nothing that is fully satisfactory has yet been found. The present inventors aimed to develop a stabilizer that is highly effective and does not cause any harm in terms of safety and hygiene. As a result of various studies using pentaerythritol, dipentaerythritol, or similar compounds that are guaranteed to have no effect on the human body, we have discovered chlorine that has an excellent stabilizing effect that has never been reported before. We succeeded in obtaining a stabilizer for containing resins and completed the present invention. That is, the present invention provides at least one selected from the group consisting of pentaerythritol and pentaerythritol dehydrated condensation polyols, polybasic acids of dibasic acid or higher, long chain fatty acids ( _C8 to _C24 ) and esters thereof. At least two selected from the group consisting of derivatives such as , acid halides, acid anhydrides, etc.
Hydroxyl group content 10-40 mixed partially esterified with seeds
% of a polyhydroxy mixed ester reaction product. In addition, the said hydroxyl group content rate is shown by the following formula. Hydroxyl group content (%) = parts by weight of hydroxyl groups in polyhydroxy mixed ester reaction product/parts by weight of polyhydroxy mixed ester reaction product x 100 Pentaerythritol and pentaerythritol dehydration condensation polyols used in the present invention include general formula() (wherein n is an integer of 0 or 1 or more) Pentaerythritols (for example,
Pentaerythritol where n = 0, dipentaerythritol where n = 1, tripentaerythritol where n = 2, tetrapentaerythritol where n = 3, etc.), as well as the general formula ()
Pentaerythritols shown in the figure have partial ether bonds within the molecule, intermediate methylol groups have ether bonds with other molecules, and even those that are connected in a network shape, and the molecules grow larger and have larger portions in various places. Examples include those with a cyclic ether structure. These polyols are by-produced during the production of pentaerythritol, or can be obtained as a mixture of polypentaerythritol by dehydration condensation of pentaerythritol by heating in the presence of an acid or base and/or a solvent or as it is. . The polybasic acids of dibasic acid or higher used in the present invention include di-, tri- or more-carbon polycarboxylic acids having 4 or more carbon atoms, such as phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, pyromellitic acid, maleic acid. , fumaric acid, itaconic acid, citraconic acid, mesaconic acid, glutaconic acid,
Propane-1,2,3-tricarboxylic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, malic acid,
Tartaric acid, citric acid, glyceric acid, 5-norbornene-2,3-dicarboxylic acid, (O-, m-, P
--) Hexahydrophthalic acid, (O-, m-, P
--) Tetrahydrophthalic acid, 1,2,3,4-butanetetracarboxylic acid, etc. On the other hand, long-chain fatty acids include higher fatty acids having 8 or more carbon atoms, such as caprylic acid, capric acid, lauric acid, palmitic acid, stearic acid,
Examples include behenic acid, oleic acid, linoleic acid, linolenic acid, ricinoleic acid, and coconut oil fatty acids. These long chain fatty acids are solid at room temperature;
Moreover, it is preferable that the obtained stabilizer is solid at room temperature. Fatty acids outside the lower limit of _C8 to _C24 are liquid at room temperature, and outside the upper limit, the obtained stabilizer becomes oily, which is not preferable. These polybasic acids of dibasic acid or higher and long-chain fatty acids, as well as their derivatives such as esters, acid halides, and acid anhydrides, can be used to partially esterify the polyols. In the present invention, for example, when 2 moles of dipentaerythritol is used as the polyol component, 1 mole of adipic acid is used as the polybasic acid component, and 1 mole of stearic acid is used as the long chain fatty acid component, the polyhydroxy mixed ester reaction product obtained is obtained. It is presumed that compounds represented by the following structural formulas are the main ones. In the present invention, by appropriately changing the molar ratio of a polybasic acid of dibasic acid or higher and a long chain fatty acid to pentaerythritol or pentaerythritol dehydration condensation polyols, a reaction having an arbitrary hydroxyl group content, ester value, and melting point can be carried out. The product can be obtained. However, the thermal stabilization effect on chlorine-containing resins is not so great when all or most of the hydroxyl groups inherent in polyols are esterified, and conversely, when the degree of esterification of the hydroxyl groups is too low, polyols are Since the disadvantages of the polyol itself will appear, the reaction product should have at least one ester bond per molecule of raw material polyol on average, and the hydroxyl group content of the reaction product should be 10 to 40%.
It is necessary to be within the range of . Examples of chlorine-containing resins that can be used with the stabilizer of the present invention include homopolymers such as vinyl chloride and vinylidene chloride, and copolymers of vinyl chloride and other olefin compounds. The stabilizer of the present invention is particularly characterized in that it imparts good thermal stability to polyvinyl chloride resins which are generally widely used. Normally, when processing polyvinyl chloride resin, commonly known metal soap type stabilizers or composite type liquid stabilizers such as calcium-zinc, barium-zinc, and magnesium-zinc stabilizers are used. The reaction product has a strong function of further promoting the stabilizing effect of these stabilizers, and its use in combination with these stabilizers is the most preferred form of use. In addition to these zinc-based stabilizers, there is no problem in using other stabilizers such as lead-based, cadmium-based, and tin-based stabilizers in combination, and the combined use of tin-based stabilizers is particularly preferred as a low-toxicity formulation. The amount of the stabilizer used in the present invention depends on the type and amount of the stabilizer, such as calcium-zinc, barium-zinc, or magnesium-zinc, but the amount of the stabilizer added is 100 parts (by weight) of the chlorine-containing resin. ) to 0.1
The higher the amount, the longer the time required for heat coloring to blacken, but in practice up to 10 parts is sufficient. The heat resistance test method is to mix according to the method actually used for processing chlorine-containing resins, knead with rolls to create a sheet, put the sheet in a gear oven, and measure its change over time. A method of observing is adopted. However, according to the test results, the phenomenon of blackening, opacity, and surface deterioration was observed early in the case where the stabilizer of the present invention was not added, but the case where the stabilizer of the present invention was added. It was shown that the larger the amount added, the longer the time until blackening. Furthermore, it has been observed that the sheet surface to which the stabilizer of the present invention was added did not lose its gloss, the flexibility of the sheet was not impaired even if it turned black, and mechanical deterioration was prevented. It was done. The polyhydroxy mixed ester reaction product of the present invention is an industrially extremely significant additive that has a variety of useful properties, including the ability to exhibit effects such as lubricity and plasticity by increasing or decreasing the degree of esterification. The stabilization mechanism of the polyhydroxy mixed ester reaction product of the present invention against chlorine-containing resins is still unclear, but it has a high hydroxyl group content, good molecular structure symmetry, and a relatively high This is thought to be based on good compatibility with resins due to molecular weight. Polyhydroxy compounds have long been known to be effective as stabilizing agents for chlorine-containing resins, and some have been put into practical use, but they have problems in terms of water solubility, sublimation, and compatibility. In particular, although pentaerythritol has been evaluated for its thermal stabilizing effect, it has a high melting point and does not melt at the processing temperature of the resin, resulting in white spots in the product and a decrease in mechanical strength. It has been pointed out. The polyhydroxy mixed ester reaction product of the present invention overcomes the above-mentioned drawbacks and further enhances the overall stabilizing effect. Of course, the stabilizer of the present invention can be used in combination with other stabilizers against heat and light, and additives such as plasticizers, lubricants, and pigments. Next, the stabilizer of the present invention will be explained with reference to Examples. Example (1) Synthesis of polyhydroxy mixed ester reaction product 254 g (1 mol) of dipentaerythritol, 73 g (0.5 mol) of adipic acid, and 142 g of stearic acid
(0.5 mol) was added and heated, and a dehydration reaction was carried out with stirring at an internal temperature of 180 to 230°C. The reaction time was 2 hours, and the amount of water removed was 26.4 g. The obtained dipentaerythritol mixed ester reaction product was poured into a vat, cooled, and then ground at room temperature to obtain a white powder. This reaction product had a melting point of 100-160°C, a hydroxyl group content of 17.1%, an ester value of 188, and an acid value of 0.8. This sample corresponds to sample No. 4 in Table 1 below. In the same manner, various polyhydroxy mixed ester reaction products (Samples Nos. 1 to 14) were obtained from the polyols shown in Table 1, polybasic acids of dibasic acid or higher, and long chain fatty acids.

【table】

[Table] (2) Chlorine-containing resin heat stabilization test The standard formulation was a mixture consisting of 100 parts of polyvinyl chloride resin, 3 parts of calcium-zinc composite stabilizer, and 3 parts of epoxy soybean oil, and the mixture as shown in Table 1 above was used as the standard formulation. Add two parts each of the various polyhydroxy mixed ester reaction products shown and knead with a roll at 190-200°C for 5 minutes to make a 1 mm thick sheet.
It was placed in a gear oven at 190°C, taken out after 10 minutes, and observed for changes in color over time (Example 1
~14). The results are shown in Table 2. For comparison, the standard formulation in which no stabilizer was added (Comparative Example 1) and the standard formulation in which 2 parts of dipentaerythritol was added as a stabilizer were also treated with heat over time in the same manner as above. Coloring, changes, etc. were observed, and the results are shown in Table 2. In addition, the stabilizers of Examples 1 to 14 in Table 2 are indicated by the sample numbers in Table 1 above.

[Table] As is clear from Table 2, the products to which the stabilizer of the present invention was added had much better thermal stability than Comparative Example 1. It has far superior thermal stability and high compatibility, and effectively prevents coloring and deterioration of polyvinyl chloride resin. Next, calculate the number of parts of stabilizer for sample No. 4 in Table 1.
The relationship between the number of blended parts and thermal stability was investigated in the same manner as above (Example 15) by varying the amount from 0.5 to 3 parts.
~18). For comparison, the relationship between the number of blended parts and thermal stability was also investigated for products in which the number of blended dipentaerythritol was varied in the range of 1 to 3 parts (Comparative Examples 3 to 5). The results are shown in Table 3.

[Table] As is clear from Table 3, when the stabilizer of the present invention is added, the blackening time becomes dramatically longer as the amount added is increased. Note that the sheet of Example 15 remained deep red and transparent even after being placed in a gear oven at 190° C. for 150 minutes, and the sheet surface did not lose its gloss and sheet flexibility.

Claims (1)

[Claims] 1. Mixed partial esterification of pentaerythritol and/or dehydrated condensed polyols of pentaerythritol with a polybasic acid of two or more basic acids and a long chain fatty acid (C ₈ to ₂₄ ) or a derivative thereof. A stabilizer for chlorine-containing resins containing a polyhydroxy mixed ester reaction product with a hydroxyl group content of 10 to 40%. 2. The stabilizer according to claim 1, wherein the dehydration condensation polyol of pentaerythritol is dipentaerythritol, tripentaerythritol or tetrapentaerythritol. 3. The pentaerythritol dehydration condensation polyol is a polyol mixture obtained by dehydration condensation of pentaerythritol or dipentaerythritol or higher polypentaerythritol as it is or under heating in the presence of a catalyst and/or a solvent. A stabilizer according to scope 1. 4 Claims in which the dibasic acid or higher polybasic acid is maleic acid, fumaric acid, succinic acid, adipic acid, sebacic acid, itaconic acid, tartaric acid, malic acid, citric acid, phthalic acid, isophthalic acid, or terephthalic acid. Stabilizer according to paragraph 1. 5. The stabilizer according to claim 1, wherein the long chain fatty acid ( _C8 to _C24 ) is caprylic acid, lauric acid, stearic acid, oleic acid, linoleic acid or behenic acid. 6. The stabilizer according to claim 1, wherein the chlorine-containing resin is a vinyl chloride resin. 7 A stabilizer for chlorine-containing resin containing polyhydroxy mixed ester with a hydroxyl group content of 10 to 40% is
The stabilizer according to claim 1, which also contains a zinc-based stabilizer such as calcium-zinc or barium-zinc.