JPS6234060B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is an improved method for granulating composite stabilizers used in the processing of chlorine-containing resins, in which several stabilizers and chlorine-containing resin powders are agglomerated under special conditions. The present invention relates to a method for producing a chlorine-containing resin composite stabilizer that is made into granules and has good non-scattering properties and good dispersibility.

Generally, stabilizers for chlorine-containing resins include metal soaps,
There are liquid composite systems, inorganic lead systems, pure organic systems, one-package systems, etc., and known auxiliary agents include epoxy compounds, antioxidants, ultraviolet absorbers, and lubricants.
However, these are usually used not alone but as a composite of several types, and the stabilizers necessary for chlorine-containing resins are mixed uniformly in advance in proportions depending on the application and are used as composite stabilizers or composite stabilizers. It is called a one-pack cage stabilizer.

Since the composite stabilizer mainly composed of inorganic lead and metal soap is in the form of powder, it has the disadvantage of scattering dust during handling and packaging, which may lead to lead poisoning problems due to lead compounds. Conventional countermeasures have been to moisten the stabilizer, make it into a paste, or make it into granules, but moistened stabilizers or stabilizers made into a paste do not have free-flowing properties and are therefore inconvenient to handle, making packaging, measuring, etc. Its working performance is poor, and its range of use is limited depending on the purpose of processing, such as whether the vinyl chloride used is soft or hard. Furthermore, the granulated stabilizer is subject to some restrictions on the composition and quality of the composite stabilizer depending on the granulation method (granulation process). Particularly in formulations with a large proportion of inorganic lead components, the problem of scattering remains.

Fundamentally researched the granulation of the composite stabilizer of the present invention,
We have succeeded in obtaining a product that is superior to conventional products using a rationally simple manufacturing method.

The present invention involves uniformly mixing (a) one or more organic acid metal salts or lubricants, (b) an inorganic lead stabilizer, and other stabilizers as necessary using a rapid powder mixer, and external heating. Alternatively, the present invention provides a method for producing a composite stabilizer for a chlorine-containing resin, characterized in that 5 to 30% by weight of a chlorine-containing resin powder is added during granulation by frictional heat.

The organic acid metal salt used in the present invention is most commonly beef tallow fatty acid, as well as saturated fatty acids having 12 to 29 carbon atoms, unsaturated fatty acids such as crotonic acid, elaidic acid, brassic acid, stearolic acid, beef tallow, etc. Natural fatty acid mixtures other than fatty acids such as Pb, Ca, Ba,
Mg, Sr, Zn, Cd salts may be mentioned, preferably those with a melting point
It exhibits a solid state at room temperature below 200℃.

As a lubricant, higher fatty acids or their esters,
Examples include micro wax, polyethylene wax, stearic acid amide, polyhydric alcohol or its ester, hydrogenated castor oil, ethylene glycol monostearate, and stearyl alcohol.

Examples of inorganic lead stabilizers include white lead, tribasic lead sulfate, basic lead sulfite, dibasic lead phosphite, dibasic lead phthalate, tribasic lead maleate, and basic lead silicate. etc. can be mentioned.

Next, as the chlorine-containing resin powder, commercially available vinyl chloride resin, vinyl chloride-vinyl acetate copolymer, vinylidene chloride resin, chlorinated polyethylene, etc. can be used, but the amount of these powder resins used is the total amount of the composite stabilizer. It is preferably between 5 and 30% by weight. If the powder resin content is less than 5%, the effect of preventing the product from scattering will be unsatisfactory, and the dispersibility in the resin during use of the product will not be sufficient.

On the other hand, even if it is used in an amount of 30% or more, no further improvement in scattering properties is observed, which is rather uneconomical.

In the present invention, other stabilizing aids such as epoxy compounds and antioxidants may be used as necessary, and ultraviolet absorbers and fillers may also be used in combination.

The stabilizer produced according to the present invention can be put to practical use in the desired particle size by appropriately sieving coarse particles and fine particles, but it is possible to obtain a stabilizer with a particle size of 28 to 150 mesh at a higher yield than conventional methods. This is also a feature of the present invention.

For carrying out the present invention, a rapid mixer such as a Henschel mixer, a super mixer, etc. is used. In order to generate frictional heat in the composition mixture by the rotation of the rotor of the rapid mixer and to raise the temperature of the molten substance in the mixture to just before the melting temperature, there is a relationship between a certain rotation speed and kneading time.

According to experimental research, when the rotor is stirring and mixing, the temperature of the composition mixture continues to rise slowly due to the heat generated by mutual friction, and when the surface of the fusible substance reaches a temperature close to its melting point, the rotation of the rotor stops. The load increases rapidly, the current load on the motor increases rapidly, and the material temperature also exhibits rapid fluctuations. Sintering granulation is achieved by identifying, measuring, and controlling this point using an ammeter or the like.

Further, in order to accelerate the granulation operation, heating can be applied from the outside as appropriate.

Example 1 35 kg of tribasic lead sulfate, 5 kg of lead stearate, 1 kg of antioxidant (bisphenol A) and 9 kg of polyvinyl chloride resin powder (Zeon 103EP) were mixed in a 200 super mixer and the mixture was heated at an internal temperature of 90°C.
Mix and granulate for 15 minutes. The produced granules were sieved to obtain particles with a particle size of 28 to 150 mesh and low scattering properties at a yield of 85%.

Further, when the dispersibility of this product in vinyl chloride resin was tested, it showed excellent dispersibility. That is, 100 parts by weight of vinyl chloride resin, 50 parts of dioctyl phthalate,
1 part of watching red toner, 5 parts of granular stabilizer
The semi-gelled material was taken out as a sheet using a 6-inch mixing roll (temperature: 160°C), and the state of the particles present in the sheet was visually determined.

In addition, when the above formulation except for the polyvinyl chloride resin powder was granulated using the same method, the yield was about 40%, and both the scatterability and dispersibility were unsatisfactory.

Example 2 40 kg of tribasic lead sulfate, 2.7 kg of beef tallow fatty acid and 10.7 kg of polyvinyl chloride resin were mixed in a 200 super mixer and mixed and granulated for 10 minutes at an internal temperature of 73°C. The generated granules are sieved and the particle size is 28~
A low-scattering product of 150 mesh was obtained with a yield of 90%. Further, when the dispersibility of this product in vinyl chloride resin was tested in the same manner as in Example 1, it showed excellent dispersibility.

Example 3 Dibasic lead sulfite 30Kg, lead stearate 15Kg,
5 kg of calcium stearate and 13 kg of vinyl chloride resin were mixed in a 200 super mixer and mixed and granulated for 30 minutes at an internal temperature of 105°C.

The produced granules were sieved to obtain particles with a particle size of 28-150 mesh and low flyability with a yield of 90%. Further, when the dispersibility of this product in vinyl chloride resin was tested in the same manner as in Example 1, it showed excellent dispersibility. Furthermore, when the above formulation except for the polyvinyl chloride resin powder was granulated using the same method, the yield was about 45%, and the scatterability and dispersibility were unsatisfactory.

Claims (1)

[Claims] 1. Mix uniformly (a) one or more organic acid metal salts or lubricants, (b) an inorganic lead stabilizer, and other stabilizers as necessary using a rapid powder mixer, and then apply external heat or friction. When granulating by heat, 5
A method for producing a composite stabilizer for chlorine-containing resins, which comprises adding ~30% by weight of chlorine-containing resin powder.