DE963191C - Process for the production of elastic materials - Google Patents

Description

The main patent 877 669 relates to a process for the production of elastic materials using natural rubber, synthetic rubber, polyvinyl chloride or mixtures thereof and lignosulfonic acid masses; namely, the raw materials mentioned are to be up to 100 ° / ₀ mixed by Ligninsulfonsäuremasse obtained by treating originating from Sulfitcelluloseablaugen Ligninsulfonsäurebestandteilen with 10 to 30% of such liquids which dissolve the lignin in molecular or colloidal distribution, wherein after which the mixture is further processed at elevated temperature until the lignosulfonic acid mass is a homogeneous material with the starting mass.

With the diverse uses, the elastic materials of the present type in the Technology and in the consumer goods industry, the demands on these substances are also special in terms of their physical properties, such as hardness, strength, etc., extremely variable and manifold. It is therefore desirable to have a wide range of different raw materials available.

It has been found that it is possible to use the method of the main patent to improve even further and

to produce elastic materials, which are in different relation to those according to the main patent obtained products have improved properties, if one in the process of Main patent as lignosulfonic acid components from sulfite cellulose liquor products used that contain zinc contained in chemical bond. In particular, the tear strength, the elongation and the structural strength even further improved.

ίο The lignosulfonic acid components that zinc is in chemical bond can be prepared in various ways from sulntcellulose waste liquors will. For example, this can be done, preferably at an elevated temperature, with zinc oxide or zinc hydroxide or convert zinc salts. In a further embodiment of the invention, it has proven to be particularly expedient " shown, if one starts from sulntcellulose waste liquors, which were obtained by the calcium sulphite process, and these, expediently after prior thickening, with calcium falling zinc salts, such as zinc sulfate, zinc carbonate or zinc oxalate. Particularly good results are obtained if the sulphite liquor is first subjected to fractional precipitation, for example with lime, subjecting and converting one or more fractions with zinc salts. As is well known the highest molecular fractions fall out first in such a fractionation, you have it here in the hand to select fractions of the desired molecular weight for the reaction with zinc at will and thus certain rubber technology in the further processing according to the invention To achieve effects.

In many cases it is particularly advantageous to use the one for the processing of the to be manufactured Elastic material desired or required additives, such as plasticizers and fillers, already the Lignosulfonic acid mass added before its incorporation into the elastic material. It turned out to be particularly favorable if the lignosulfonic acid mass is already softening or plasticizing Incorporated substances. Such mineral oils, for example, preferably mineral oil products with a high Content of unsaturated components, also natural or synthetic fats or fatty acids, fatty acid mixtures obtained preferably from yeast.

example 1

100 kg of a fermented, neutralized, recovered by the CAI ciumsulfitverfahren Fichtensuhitablauge are evaporated at 42 _^0/0 of dry substance and with 25 kg of ZnSO ₄ · 7 H ₂ O at 8o ° with stirring. The reaction product is then atomized. 7 parts of the powdery product obtained by atomization are mixed with 2 parts of ethylene glycol and 1 part of water to form a paste.

9 parts by weight of this paste are combined with 100 parts

Natural rubber (smoked sheets), 7 parts of active aluminum silicate, 1 part of dibenzothiazyl disulfide, 0.5 parts of diphenylguanidine, 3 parts of sulfur and 3 parts of zinc oxide worked together in a kneader.

For comparison, a rubber base mixture was produced without the addition of the paste according to the invention

and also a product in which, instead of the paste, the same amount of lignosulphonic acid components containing zinc in bound form from the same sulphite waste liquor, but in dry form, was incorporated. The three products gave the following values in the mechanical test, with A denoting the rubber base mixture without the additive according to the invention, B denoting the base mixture into which the dry product was incorporated, and C denotes the elastic material according to the invention. The vulcanizates produced at 143 ^{° C. were tested.}

ABC

Tensile strength kg / cm ² 86 149 219

% Elongation to break .... 435 496 514

Shore hardness 57 59 78

Tear resistance kg / cm 36 22 91

Pull-out strength kg / cm 43 28 87

Example 2

100 kg verhefte Birkensulfitablauge are mixed with 12.7 kg of zinc carbonate and stirred for 2 hours at 70 ^0th Half of this mixture is evaporated to a dry content of 50%, the other half is evaporated to a dry content of 40% and then converted into solid form by a drum dryer.

43.8 parts of the evaporated to 50% product and 24 parts of the dried and pulverized product with 9.4 parts 2g ^o / _o solution of formaldehyde, 2 parts of aniline, 4.8 parts of 50 ° / _O are then used for the preparation of a sodium hydroxide solution Ligninsulfonsäuremasse and 10 parts of a fatty acid mixture obtained from yeast mixed at 80 ° C.

30 parts of the above lignin mass are added to 100 parts of natural rubber (smoked sheets) together with 25 parts of active aluminum silicate, 25 parts of alumina gel, 5 parts of zinc oxide, 3 parts Stearic acid, 1 part dibenzothiazyl disulfide, 0.4 part diphenylguanidine and 3 parts sulfur on the roller incorporated.

The elastic material produced as above and ^{vulcanized at 143 °} C. was subjected to mechanical tests, as was a product produced according to the method of the main patent. The following results were obtained, I denoting the product according to the present invention and II denoting the product obtained by the process of the main patent.

I II

Tensile strength kg / cm ² 200 155

% Elongation to break 592 556

Voltage values

at extension of 300% km / cm ^a 76 58

Voltage values

at elongation of 500% kg / cm ² 169 133

Shore hardness 71 68

Impact elasticity DIN in ° / ₀ 57 45

Tear resistance kg / cm 85 42

Pull-out strength kg / cm 84 53

The comparative figures given in connection with the examples from test experiments with inventive

moderate products and those that have been obtained in a different, but similar and comparable way, clearly show the advantages achieved with the invention and the superiority of those obtained in this way Recognize products. The check numbers of the products from Example ι show in particular that by adding Lignosulphonic acid compounds containing zinc in chemical bond to elastic materials of theirs Strength properties are improved, but that this is particularly the case when the zinc-containing lignosulphonic acid mass in the form according to the invention introduced into the elastic material will. Above all, reference should be made to the tear resistance and the pull-out strength. The test paying Products according to Example 2 further show that the present invention eliminates the process experienced another significant improvement after the main patent.

Since a plasticizer was added in this example, the Shore hardness was compared to the comparison product not as enlarged as z. B. Tear resistance and pull-out strength; but were In addition to strength, the elasticity values of the product are also significantly improved.

Claims (4)

Patent claims: i. Process for the production of elastic materials, consisting of natural or synthetic Rubber, polyvinyl chloride or their mixtures, according to patent 877 669, according to the these substances are additionally mixed with lignosulphonic acid components, characterized in that that as lignmsulfonic acid components from sulphite waste liquors products are used that Contains zinc in chemical bond. 2. The method according to claim 1, characterized in that that products are used as lignosulfonic acid constituents, which are made according to the Sulphite waste liquors obtained from calcium sulphite processes by converting them, expediently after thickening, with calcium precipitating zinc salts such as zinc sulfate, zinc carbonate or zinc oxalate became. 3. The method according to claim 1 or 2, characterized characterized in that products are used as lignosulphonic acid constituents which are made from sulphite waste liquor by fractional precipitation and conversion of one or more fractions with the formation of Zinc salts of lignin sulfonic acid were obtained. 4. The method according to claim 1, characterized in that that the lignosulphonic acid before its incorporation into the elastic material is plasticizing or plasticizing substances such as mineral oils, preferably mineral oil products with a high Content of unsaturated components, natural or synthetic fats or fatty acids, preferably Fatty acid mixtures obtained from yeast can be added. Considered publications:
Transactions of the Institution of the Rubber Industry, Vol. 24 (1948/49), p. 235, last paragraph. © 609 706/415 10.55 (609 873 4.57)