DE2124040B2 - Process for the production of a granulated stabilizer preparation for vinyl chloride polymers - Google Patents

Description

The invention relates to a process for the production of a granulated stabilizer preparation for vinyl chloride polymers, in which one or more known as stabilizers for vinyl chloride polymers Metal salts of fatty acids in powder form with a melting point below 200 ° C, optionally with the usual Fillers or pigments in a high speed rotary mixer be homogenized with an increase in temperature.

A stabilizer for vinyl chloride polymers is known (US Pat. No. 2,744,881), the basic aliphatic one Contains lead dicarboxylates.

It is also a stabilizer for vinyl halide polymers known (DT-AS 14 94 223), which consists of a basic lead salt of an oxygen-containing acid and a barium salt of a fatty acid having 6 to 20 carbon atoms, the barium salt component not significantly less than 1% and not significantly more than 40% by weight of the stabilizer, based on the lead oxide content of the basic lead salt.

Such stabilizers are harmful to human health because of handling them Dust is created that contains metals such as lead, barium, cadmium, etc.

There is also a method of the type mentioned is known (GB-PS 11 78 847), in which a special, granulating substance with a low melting point is added, which by feeding of heat (e.g. frictional heat from the stirring process) in a high speed mixer melted and then cooled at reduced stirring speed, whereby the Granulation is effected. This process requires a special granulating substance in add a considerable amount, which in itself has no effect on the plastic to be processed. It is also necessary to completely melt the granulating material and then cool it down again, which requires a considerable treatment time or additional devices for heating and Requires cooling.

The invention is based on the object of creating a method of the type mentioned at the outset, which - Can be carried out in a simple manner and with little effort. This procedure is characterized by that the homogenization process is carried out with a constant high number of revolutions becomes that the ID caused by the mechanical stirring te heat causes the particles to sinter and agglomerate without melting them. The homogenization process with a constant number of revolutions is preferably interrupted when the melting of the particles causes the formation of larger π agglomerates, which is caused by an erratic An increase in the torque can be seen on the agitator axis. The increase in torque is at an electrically driven mixer in a simple manner by the sudden increase in the motor current ascertain. The increase in current can then be used in a simple manner to switch off the mixer will. The method according to the invention is otherwise without an additional heating or cooling device feasible. Since the granulation takes place before the melting process, the treatment time is comparative short, and e.s the temperature is low. Also, the addition of aggregates does not affect have the plastic to be processed and are therefore unnecessary in themselves, avoided. The stabilizers will so not affected by heat either.

The starting material here contains stabilizers for

Vinyl chloride polymers, in particular a mixture of a large number of such stabilizers for Vinyl chloride polymers, for example metal salts,

r. how

Lead stearate, dibasic lead stearate,
Barium stearate, barium laurate,
Barium ricinoleate, cadmium stearate,
Cadmium laurate, cadmium ricinoleate,
in calcium stearate, calcium laurate,

Calcium ricinoleate, magnesium stearate,
Zinc stearate, zinc laurate and zinc ricinoleate,
organic compounds such as dibutyl maleate and
Dibutyl laurate,
■ ti ultraviolet absorbers, such as benzophenone and

Triazole systems.

The starting material must contain at least one fusible material. The type and amount of too The starting material used depends on the purpose to be achieved. The source material may contain pigments such as titanium dioxide, ultramarine blue, iron oxide, printing ink, etc., as well as fillers such as calcium carbonate, asbestos, etc. In addition, small amounts of liquid substances such as soft > ϊ rather, be included, e.g. B. dioctyl phthalate, dibutyl phthalate, Tricresyl phosphate, etc.

The fusible material is one of the stabilizers for vinyl chloride polymers described above, which are in the solid state bo at room temperature and whose melting point is below 200 ° C.

Examples of such fusible materials are metal salts such as barium ricinoleates, cadmium laurate, cadmium stearate, calcium laurate, calcium stearate, lead stearate, magnesium stearate, zinc laurate and zinc stearate.
The agglomeration of the starting materials is achieved by mechanical mixing of the starting material, which contains at least one fusible material, until a sudden increase

the torque on the stirrer takes place. The mechanical mixing can be done by a known mixer such as for example a super mixer or a Hendschel mixer available on the market.

The sudden increase in torque on the stirrer is determined as follows, for example: If the raw materials are mechanically mixed by a mixer and the in the raw materials containing fusible materials agglomerate, the drive torque of the rotor begins Mixer suddenly increases, which also suddenly increases the motor current. If by a If such an increase in the motor current is displayed on the ammeter, the motor is stopped.

During the mechanical stirring of the starting materials, the agglomeration force of the fusible Materials can be increased further by additionally supplied heat, for example by externally supplied hot air.

The amount of the fusible materials to be used in the method of the present invention is on does not depend on any condition provided that there are sufficient fusible materials, so that agglomeration of the starting materials can take place.

Details of the invention emerge from the following example.

example

Each sample of the starting material consists of the compositions shown in Table 1 and will Mechanically stirred with a super mixer available on the market, i.e. samples A, B, C or D (35 kg per sample) by means of a mechanical stirring movement in a 100 liter mixer, its rotor rotates at 1350 revolutions per minute, stirred.

Samples E and F (150 kg per sample) were first mixed in a 500 liter mixer, the rotor of which rotated at a speed of 335 revolutions per minute for a period of time stirred for 4 minutes and then with a ί rotor speed of 710 revolutions per Minute.

Sample G (80 kg) was placed in a 500 liter mixer at a rotor speed of 1350 revolutions per minute, and it was the sample H (80 kg) in

ι »a 500 liter mixer with a rotor speed of 355 revolutions per minute and stirred then stirred at a rotor speed of 710 revolutions per minute.

Sample I (250 kg) was in a 1000 liter mixer stirred at a rotor speed of 550 revolutions per minute for a period of 5 minutes and then stirred at a rotor speed of 275 revolutions per minute.

The increase in torque was measured by means of an ampere

2 » remeters noted.

The endpoints of the engine load are shown in Table Jl of the relevant series underlined.

The method according to the invention is further described with reference to sample A:

2> The mixer works at 1350 revolutions per minute. During the first 7 minutes there is one sudden increase in engine load was not detected while the sample temperature was linear rise. After the sample temperature to a value

) () C (increase of between 67 ° C and 70 ⁰ after about 8 minutes), the engine load increased sharply The reason is presumably that the starting materials have agglomerated by the agglomerating force of the Bleistearats and calcium stearate. this

r> can for example easily in view of the fact declare that the melting point is of Bieistearatbeil 10 ⁰ C.

Table 1

component

Sample no.
AWAY

Lead stearate sample 35 No. engine 18th 17th 15th engine 65 C. 64 33 D. 100 30th Cadmium stearate A. load load 18th Temp. 17th Temp. Calcium stearate Temp. 10 (A) 17th 16 (A) 2 Barium stearate 30th 34 17th CQ 16 67 CC) 4th CQ 10 30th 34 36 26th 36 45 29 65 64 85 34 37 30th 10 40 3 39 34 41 4th Dibasic lead stearate 3 Tribasic lead sulphate Triphenyl phosphite 10 Stearic acid 40 Ultraviolet absorber B. the triazoles Temp. engine engine pigment load load Calcium carbonate CQ (A) (A) Table 2 37 34 18th Rotor agitator 38 34 17th speed 39 34 18th age (Rpm) (min) 1350 1 1350 2 1350 3

J-ortscl / ιιημ Kiihr IVoIh- No. Moliii ' Ii Miilor- ( MoI (M- I) Moloi KoK) I / CIl Λ beliisiiiiif! 'Temp. l) ol; is I iiny Temp. heli performance Temp. bcliistuntj speed Temp. (A) (Λ) (A) (Λ) age 30th (C) 34 (O 34 (C) 18th (min) (c) 30th 40 23-34 41 23-31 39 35 (Rpm) 4th 44 31 46 22-31 45 25-31 <5 1350 5 59 38 50 23-35 50 26-35 1350 6th 61 51 55 23-37 55 23-37 1350 7th 67 56 24 57 28 1350 8th 70 60 23-26 60 28 1350 9 64 25th 64 31 1350 10 66 31 65 48 1350 Π 71 47 72 1350 12th 70 1350 13th 1350

Table 2 continued

Particle size distribution ABCD after magnification o / _o o / _o o / _o o / ₀

Stirring > 0.25 mm load F. 23 15th 18th 30th Rührveit sample No. engine / eit 0.25-0.15 mm (A) Tr mp. 26th 25th 26th 35 G load 0.15-0.075 mm 135 49 50 47 20th Temp. (A) <0.075 mm 145 CC) 12th 10 9 15th Rolor (min) Sample no. 175 31 Rotor- (min) CC) seen win- 1 E. 250 30th jreschw digkeil digkcil 2 64 32 Engine- 3 Temp. Engine 64 32 load 60 (Rpm) 4th 70 39 (A) (Rpm) 355 5 CQ 40 145 5 83 355 7th 30th 70 150 60 355 9 31 73 41 190 60 355 10 31 75 250 10 89 710 11 32 65 1350 12th 92 60 710 13th 36 80 49 68 65 710 15th 38 91 50 14th 95 710 16 41 205 50 70 1350 16 97 95 710 17th 50 1350 710 18th 43 18th 99 710 19th 45 75 1350 710 50 80 1350 710 155 710 51 205 1350 710 52 53

Distribution of the particle size E F

after enlargement n / ₀ o / _o

Stirring time > 0.6 mm mm 20th 18th 15th Sample no. engine 62 60 30th I. load 0.6-0.25 mm 5 7th 25th Temp. (A) 0.25-0.15 13th 15th 10 20th rotor (min) <0.15mm engine rotor Stirring time (° Q 20th speed 0 Sample no. load speed 30th 22nd 5 H (A) 40 22nd 10 Temp. 62 45 (Rpm) 15th 62 (Rpm) (min) 50 355 ("C) 62 550 0 355 45 63 550 1 355 50 550 2 355 54 550 3 62

continuation

Rotor-

speed

(Rpm)

Stir / hurry

(min)

20th
22nd
24
25th

Sample no.

Il

Te nip.

(C)

71
75
78
79

Rotor- Agitation Sample no. Engine- speed I. bclastting Moior Temp. (A) back-up 26th (Λ) (Rpm) (min) ("C) 40 67 550 4th 57 34 71 550 5 62 35 75 275 6th 63 40 90 275 7th 64 275 8th 65

Distribution of particle size H

after enlargement o / _o

> 0.6 mm 40

0.6-0.25mm 28

0.25-0.15mm 27

<0.15mm 5

They are comparative tests on the appearance and the dispersibility in polyvinyl chloride between sample I, which has been prepared according to the aforementioned example, and the granular or powdery stabilizer obtained by a known melting process has been carried out. The granular stabilizer obtained by the process of the invention has due to the agglomeration force of the meltable materials, an enlarged grain size, while the granular or powdery stabilizer obtained by the known method from molten Substances. That is why the two granular or powdery stabilizers are different in appearance different. The granular stabilizer produced by the process of the present invention has an important one better dispersibility in the polymers than that obtained by the known melting process Stabilizer. The dispersibility of the stabilizer prepared by the known method is not improved even if these granular stabilizers are constantly mechanically agitated.

From the example described it also emerges that with the method according to the invention, even then when the starting materials are lesser amounts of

jo contain fusible materials than those with the known melting processes manufactured materials, the starting materials by the agglomeration power of the contained meltable materials with their grain size can be easily increased.

Claims (2)

Patent claims: 1. Process for the production of a granulated stabilizer preparation for vinyl chloride polymers, in which one or more metal salts known as stabilizers for vinyl chloride polymers of fatty acids in powder form with a melting point below 200 ° C, possibly with conventional fillers or Pigments in a high speed rotary mixer are homogenized with an increase in temperature, characterized in that that the homogenization process is carried out at high speed in such a way that the heat caused by the mechanical agitation sintered and agglomerated the particles without melting them. 2. The method according to claim 1, characterized in that the Homogenisierungsvorgar.g with a high number of revolutions is terminated when the melting of the particles causes the formation larger agglomerates is caused, which is caused by a sudden increase in the torque at the Stir axis is recognizable.