DD219494A1 - STABILIZATION SYSTEM FOR POLYVINYL CHLORIDE - MOLDING - Google Patents

Abstract

The invention relates to a present in solution stabilizer system for the stabilization of predominantly PVC existing polymers or mixtures consisting mainly of PVC, against thermooxydative degradation, consisting of carboxylates branched-chain carboxylic acids and / or alkylphenolates of metals of the second group of the Periodic Table of the Elements, organic phosphites and optionally further costabilizers, which represent 0.1 to 5.0% by weight, based on the stabilizer system, monocarboxylic acids of the general formula R 2 -R 1 R 2-C-COOH R 3wherein R 1, R 2, R 3 are H and / or halogen, contained alone or in combination. The stabilizer system makes it possible to produce transparent molding compositions or finished articles without impairing the other performance properties.

Description

Stabilizer system for polyvinyl chloride molding compounds Field of application of the invention

The invention relates to a stabilizer system for polyvinyl chloride molding compositions consisting of carboxylates branched-chain carboxylic acids and / or alkylphenolates of metals of the second group of the Periodic Table of the Elements, organic ".

Phosphites and optionally further costabilizers, in the form of a solution.

In particular, this stabilizer system is suitable for highly transparent PVC moldings, being used in a wide variety of processing forms of polyvinyl chloride, such as calender or extruder processing

Characteristic of the known technical solutions

Liquid, consisting of several components stabilizer systems for polyvinyl chloride molding compositions have been described many times and have been known for some time. In this context, it is known to use liquid stabilizers which use carboxylates of branched-chain carboxylic acids and / or alkylphenolates of metals of the second group of the Periodic Table in combination with organic phosphites and optionally further costabilizers.

A disadvantage of such stabilizer systems, however, is that they are not suitable for obtaining highly transparent molding compositions.

Thus, a stabilizer system is known which consists of a cadmium salt of an organic carboxylic acid, a barium or strontium salt of an organic carboxylic acid and a zinc salt of an organic carboxylic acid, said mixture additionally containing a higher alkyl monoether of an alkylene glycol and an organic carboxylic acid.

The disadvantage of this stabilizer combination is that only the storage stability of the stabilizer combination increases, but.

No improvement in performance characteristics, such as the transparency of using the

Stabilisatorsystems produced PVC molding compositions, is achieved. (DE-OS 1694624) -

It is furthermore known to use lead salts of a branched-chain carboxylic acid having carbon numbers of 3-12 in the preparation of transparent PVC molding compositions in order to improve the transparency of the molding compositions.

This method has the disadvantage that due to the lead content, the light stability, is reduced and the molding compositions tend increasingly to discoloration. (DE-OS 1569363)

Object of the invention

The object of the invention is to provide a liquid stabilizer system for processing PVC or predominantly PVC-based polymers or polymer blends into the corresponding molding compositions which are suitable for producing transparent finished articles based on known carboxylates of branched-chain carboxylic acids and / or Alkylphenolates of metals of the 2nd group of the periodic table, organic /! Phösphiten and optionally further costabilizers to provide. ,

Explanation of the essence of the invention

The invention has for its object to develop a stabilizer system for the stabilization against thermo-oxidative degradation in the processing of PVC or predominantly PVC existing polymers or polymer blends to transparent molding materials or finished articles consisting of known carboxylates branched-chain carboxylic acids and / or alkylphenolates of Metals of the second group of the periodic table, organic Phösphiten and optionally further costabilizers and transparency-improving modifiers.

This object is achieved in that the stabilizer system as modifier component 0.1 to 5.0 wt .-%, based on the stabilizer system, monocarboxylic acids of the general formula

Rp-C Gooh

where R ₁ , R ₂ , R ₃ = H and / or halogen

mean to be added alone or in combination. The stabilizer system according to the invention makes it possible to produce transparent molding compositions or finished articles without further performance properties of the polymer composition

be affected. ._ __

As monocarboxylic acids, acetic acid, trichloroacetic acid or bromoacetic acid can be used individually as well as in combination.

embodiments

.1. To TOO parts suspension PVC with a K value of 70 are 2.0 parts of a stabilizer system consisting of 31.4% Ba-isononylphenolate solution 20.6% Cd-2-ethylhexoate solution

6.5% Zn-2-ethylhexoate solution

5.0% di-tert-butyl-p-cresol, 23.5% triisononylphenyl phosphite

8.0% epoxidized soybean oil

5.0% acetic acid

and 43 parts dioctyl phthalate added and mixed thoroughly in the mixer at room temperature. From the PVC plasticizer-stabilizer mixture thin films were produced on a rolling mill. These films were pressed in a press on 180 ^c 0 to 2 mm test plates at which the turbidity or transparency can be assessed

   To assess the transparency, an objective measurement method was used in which turbidity phenomena are determined by transmission measurement with the spectrophotometer Spekol. Measured by this method,. compared to the unattenuated central beam. In this case, the transmission is 100%, which corresponds to 0% turbidity

 The measurement of the 2 mm test plate of Example 1 gave a transmission of 95.8% (= 4.2% haze).

2. 2.0 parts of a stabilizer system, which consists of the following individual components, is mixed with 100 parts of suspension PVC having a K value of 70 and 43 parts of dioctyl phthalate according to Example 1 and pressed into test plates: 50.0% Ba isononanate / isononylphenolate solution ', ..

18.6% Zn-2-ethylhexoate solution

, 5.0% di-tert-butyl-p-cresol 26.3% diphenylalkyl (Ci2-Ci _S ) -phosphit 0.1% trichloroacetic acid. '' ....

The measurement of the 2 mm test plate gave a transmission of 96.8% (= 3.2% haze).

3. To 100 parts of suspension PVC having a K value of 70, 2.0 parts of a stabilizer system consisting of 51.8% Ca-isononylphenolate solution /. '. ·; 21.4% Zn isooctylphenolate solution

5.0% 2,2-bis (4-hydroxyphenyl) -prbpan 18.8% diphenyldecyl. '

2.0% bromoacetic acid

1.0% acetic acid.

and 43 parts of dioctyl phthalate added. It is proceeded in the same manner as in Embodiment 1. The transmission measurement gave a value of 96.1% (= 3.9% haze).

4th Comparative Example

Compared to Embodiment 1, to 100 parts of suspension PVC having a K value of 70, 2.0 parts of a stabilizer system of the same composition as in Working Example 1 but without the modifier component of the present invention and 43 parts of dioctyl phthalate are added.

The measurement of the test plates prepared in the same way as in Ausführungsbeispiei 1 gave a transmission of 72.0% (= 28.0% haze).

While the test plates according to the invention (according to Example 1-3) were highly transparent even when visually assessed, the test plates according to the comparative example appeared to be significantly clouded

 All other utility parameters (thermal stability, initial color) were comparable in all examples.

Claims (2)

Invention claim: 1. Stabilizer system for polyvinyl chloride - molding compositions consisting of carboxylates of branched-chain carboxylic acids and / or alkylphenolates of metals of 2. Group of the Periodic Table of the Elements, organic Phösphiten and optionally further costabilizers in the form of a solution, characterized in that as modifying component 0.1 to 5.0Gew .-%, based on the stabilizer system, monocarboxylic acids of the general formula wherein R ₁ , R ₂ , R ₃ = H and / or halogen, are added alone or in combination.