CS270205B2 - A mixture for coating rolls of textile machines and a method for producing them - Google Patents

Abstract

The mixture for coating the rollers of textile machines, especially spinning and pre-spinning machines, consisting of synthetic rubber, a reinforcing agent, a vulcanization accelerator, an activator, an antioxidant, as well as a hydrophilic substance in the form of modified zinc chloride, contains as a hydrophilic substance zinc chloride and a complexing dispersant in the form of benzoic acid in a mass amount of 1 to 2oo%, based on the mass of zinc chloride, and triethanolamine in a mass amount of 1 to 2oo%, based on the mass of zinc chloride. It is produced by preparing a premix of a paste of zinc chloride and a complexing dispersant in the form of benzoic acid and triethanolamine at a temperature of 293 to 480 K, after which the paste thus prepared is mixed with the remaining components of the mixture.

Description

The subject of the invention is a mixture for coating textile rollers.

One of the most important components of mixtures for coating rolls of textile machines is zinc chloride, which has the role of the hydrophilic component of this mixture. Zinc chloride introduced into the mixture without prior modification immediately reacts with the component of the mixture that has the role of the elastomer, which causes undesirable vulcanization and sticking of the mixture. Therefore, modification of zinc chloride is necessary before its introduction into the mixture. The mixture for coating textile machine rollers according to Polish patent specification No. 133 381 consists of polar synthetic rubber, a reinforcing agent, a vulcanization accelerator, an activator, a mixture of filler with inorganic pigments, an antioxidant, an antistatic agent, or a condensation resin, an organic pigment, a hydrophilic substance and a plasticizer, and contains zinc chloride as the hydrophilic substance and additionally contains 5 to 30% ammonia water in a weight amount of 1 to 100%, based on the weight of zinc chloride, as well as a complexing dispersant or a mixture of complexing dispersants, preferably disodium salt of ethylenediaminetetraacetic acid in a weight amount of 1 to 100 based on the weight of zinc chloride. >

The method according to the invention for producing a mixture for coating textile machine rollers consists in preparing a zinc chloride paste with ammonia water in a weight amount of 1 to 100 based on the weight of zinc chloride, with the addition of a complexing dispersant or a mixture of complexing dispersants in a weight amount of 1 to 100 based on the weight of zinc chloride, after which a premix is prepared at a temperature of 333 to 473 K and a shear rate of 10 to 100 s for a time of 30 to 1 200, which contains 100 parts by weight of rubber or rubber mixture, 5 to 50 parts by weight of plastomer, 3 to 25 parts by weight of a mixture of filler and inorganic pigment, 2 to 10 parts by weight of a previously prepared zinc chloride paste, 0.1 to 10 parts by weight of an antistatic agent, 0.5 to 10 parts by weight of a vulcanization accelerator and optionally 5 to 50 parts by weight of condensation resin, after which the usual components are introduced into the premix thus prepared, i.e. 0.3 to 6 parts by weight of reinforcing agent, 0.3 to 6 parts by weight of vulcanization accelerator, 0.5 to 5 parts by weight of antioxidant, 0.5 to 5 parts by weight of organic pigment and then the new premix is processed at a temperature of 293 to 413 K and a shear rate of 100 to 100 s for a time of 60 to 2400 s and the finished mixture is vulcanized in a manner known per se.

The mixture according to the invention for coating textile machine rollers contains zinc chloride as a hydrophilic substance and a complexing dispersant in the form of benzoic acid in an amount by weight of 1 to 200%, based on the weight of zinc chloride, and in the form of triethanolamine in an amount by weight of 1 to 200%, based on the weight of zinc chloride.

The method according to the invention for producing a mixture for coating textile machine rollers consists in pre-preparing a premix of zinc chloride paste with a complexing dispersant in the form of benzoic acid in a mass amount of 1 to 2oo%, based on the mass of zinc chloride, and triethanolamine in a mass amount of 1 to 2oo%, based on the mass of zinc chloride, at a temperature of 293 to 48o K, after which the paste prepared in this way is mixed with other components of the mixture.

The zinc chloride charge modified with benzoic acid and triethanolamine as hydrophilic substances improves the processing properties of the mixture both on a laboratory and industrial scale, and the coatings produced from the mixture according to the invention are characterized by high utility properties.

The method according to the invention is further illustrated by the following example, the scope of the invention being not limited by this example.

CS 27o2o5 B2

Example

Mixture composition Parts by weight

Butadiene-acrylonitrile rubber, Nipol-41loo

Styrene-acrylonitrile copolymer, burane 358 N2o

Zinc oxide5

Stearin1.5

Tetramethylthiurammonosulphide1,5

Dibenzothiazolyl disulfide1,5

Sulfur3.5

2,6-Di-tert-butyl-(4-methylphenol)1,0 í Zinc chloride4,5

Benzoic acid ,4.9

Triethanolamine4,o i’

The paste of zinc chloride with benzoic acid and triethanolamine, prepared at a temperature of about 300 K, is then mixed with rubber, a copolymer of styrene with acrylonitrile, zinc oxide and stearin at a temperature of about 400 K at a shear rate of 10 s for a period of 480 s. The remaining ingredients are added to the premix prepared in this way and everything is mixed again at a temperature of 293 K and a shear rate of ^{10 -1} s*^ for a period of 600 s. The mixture obtained is vulcanized in an electrically heated press from a pressure of 6 MPa at a temperature of 443 K. The mixture prepared according to the example has the processing properties which are given in the table of processing properties (the composition is given in parts by weight):

The first mixture is Nlpol N-41 rubber: 100, Luran 358 N copolymer: 20, zinc oxide: 5, stearin: 1.5, tetramethylthiuram monosulfide: 1.5, dibenzothiazolyl disulfide: 1.5, sulfur: 3.5, 2,6-di-tert-butyl- (4-methylphenol): 1, zinc chloride: 4.5, that is, it is unmodified zinc chloride;

Second mixture:

rubber Nlpol N-41: loo, Luran 358 N copolymer: 2o, zinc oxide: 5, stearin: 1.5, * tetramethylthiuram monosulfide: 1.5, dibenzothiazolyldisulfide; 1.5, sulfur: 3.5, 2.6—dl—tert.-butyl— —(4-methylphenol) : 1, zinc chloride t 4.5, disodium ethylenediaminetetraacetic acid salt: 1.5, 3o% ammonia water: o.7, i.e. a mixture with modified zinc chloride As in Polish patent specification No. 133 381.

Table

Property type of mixture with unmodified zinc chloride with modified zinc chloride according to patent No. 133 381 processed As in the example

Preparation of the mixture:

- when using cooled rollers difficult no problems no problems

CS 27o2o5 B2

- when using cylinders with a temperature of 4o °C very difficult not too light no problem — at lower friction, t - l,o2 difficult without difficulty no problem — at higher friction, f - 1.2 very difficult not too light no problem mixture workability difficult not too light light tendency to vulcanize large slight ' small Mixture morphology Bad _ satisfactory good

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Claims (2)

pWhereas the invention 1. · A mixture for coating textile machine rollers, comprising polar synthetic rubber, a reinforcing agent, a vulcanization accelerator, an activator, a mixture of filler with inorganic pigments, an antioxidant, an antistatic agent, optionally a condensation resin, an organic pigment, a hydrophilic substance in the form of modified zinc chloride and a plastomer, characterized in that it contains zinc chloride as the hydrophilic substance and a complexing dispersant in the form of benzoic acid in an amount by weight of 1 to 2oo based on the weight of zinc chloride, and triethanolamine in an amount by weight of 1 to 2oo% based on the weight of zinc chloride. 2. ' A method for producing a mixture for coating textile machine rollers, consisting in preparing a premix of 100 parts by weight of rubber or a rubber mixture, 5 to 50 parts by weight of plastic, 3 to 25 parts by weight of a filler mixture * inorganic pigment, 2 to 10 parts by weight of a hydrophilic substance in the form of a pre-prepared paste of modified zinc chloride, 0.1 to 10 parts by weight of an antistatic agent, 0.5 to 100 parts by weight of a vulcanization accelerator, and optionally 5 to 50 parts by weight of a condensation resin, at a temperature of 333 to 473 K and a shear rate of 10 to 100 * during a period of 30 to 1200 s, adding the remaining components of the mixture, i.e. 0.3 to 6 parts by weight of a reinforcing agent, 0.3 to 6 parts by weight of a vulcanization accelerator, 0.5 to 5 parts by weight of an antioxidant and 0.5 to 5 parts by weight of an of organic pigment, followed by new mixing of all components at a temperature of 293 to 413 K and a shear rate of 10 to 100 s for 60 to 2400 s, until a homogeneous mixture is formed in a vessel or boiler; characterized in that a premix of zinc chloride paste and a complexing dispersant in the form of benzoic acid in a mass amount of 1 to 200 based on the mass of zinc chloride, and triethanolamine in a mass amount of 1 to 200% based on the mass of zinc chloride, is produced at a temperature of 293 to 480 K and the paste thus obtained is mixed with the remaining components of the mixture.