DE1494858C3 - Process for the production of copolymers and their use as tanning agents - Google Patents

Description

is a high quality tanning agent for leather and has the advantage that the grain of the leather does not crack or becomes brittle even if the leather is not treated with a grease agent.

With the specified ratio of the acid component and the oil component, the acid is approximately four to eight times the sulfated oil. The initiator is used in amounts of 0.5 to 6 percent by weight, calculated on the monomer. Suitable initiators are, for example, hydrogen peroxide, Ammonium persulfate, sodium persulfate, potassium persulfate.

The dosage of the chain terminator depends on the particular terminator selected and its effectiveness in regulating the molecular weight of the copolymer. In general, the Amount of chain terminators in relation to the amount of initiator used, so that a copolymer which occurs in the acid form at a concentration of approximately 33% in water 25 ° C has a viscosity in the range up to about 300 ° poisen. A chain terminator is not necessary if the amount of initiator used is high enough to produce a copolymer in the range of the low molecular weight just given. As the most favorable molecular weight is considered to be from about 5,000 to about 50,000. Suitable chain terminators are including hydroxylamine and its salts, for example hydroxylamine sulfate, also mercaptoethanol, Mercaptopropanol, thiodiglycol, thioglycolic acid, ascorbic acid and isoascorbic acid. The chain terminator can be used in amounts of about 0.2 to 3.5 percent by weight, calculated on monomers Acid.

The copolymers of the invention are soluble in water and dilutable with water. They stay any time in solution without any significant separation of oil taking place. Their excellent tanning properties have already been mentioned.

For tanning hides and skins, the copolymers of the invention in water become one Concentration of about 5 to about 40 percent by weight dissolved. Needless to say, the copolymers need not to be isolated from the aqueous solution in which they were made. Much more you can adjust the polymerization solutions yourself to the desired concentration for tanning will. 3 to 8% of a salt, such as common salt or sodium sulfate, is added to the tanning solution. the Tanning liquid is poured into a suitable vessel, for example one of the usual tanning drums, and then the skins are put into the drum. The tanning liquor is generally dimensioned so that about 20 to 25% effective tanning substance, calculated on the weight of the wet pimped skin, and about 5 to 15% salt, if used, is present. For tanning the skin is tumbling with the drum at room temperature and up to a maximum of 35 ° C offset. Treatment can continue for about 4 to 24 hours. Generally one works at 28 to 32 ° C.

This tanning can be followed by a mineral tanning, especially with chrome, a tanning with film with vegetable tanning agents or synthetic tanning agents.

Should a skin tanned with mineral tanning, especially with chrome or zirconium or in some other way are retanned, a liquor containing 0.5 to 10 percent by weight of the copolymer is used of the invention, generally without salt. About 1 to 5 percent by weight copolymer, calculated on wet, pre-tanned chrome leather, should be present. To get 3% on the leather, you turn calculated on leather weight, 200% liquor at that

ίο contains 1.5% copolymer.

The copolymer produced by the process of the invention is suitable for treatment all kinds of hides and leather, such as horse, cattle, kid, lamb, goat or pig, and for production all types of leather for shoe upper leather, soles, clothing, haberdashery, upholstered furniture and commercial Leather. It can also be used for pre- or retanning.

Example 1 It is produced.

Solution A:

312g aqueous sulfated castor oil (234 g pure oil),
1860 cm ³ of deionized water;

Solution B:
1200 g methacrylic acid,

168 cm ^{3 of} aqueous hydroxylamine solution (6.0 g of hydroxylamine);

Solution C:

52 g aqueous hydrogen peroxide solution (35%) (ISgH ₂ O ₂ ),
600 cm ^{3 of} deionized water.

The solution A is heated to 90 ° C. in a glass vessel and then set in portions at the same time within of 50 minutes, the solutions B and C through the dropping funnel or the like. While the temperature is kept at 89 to 93 ° C. You hold that afterwards

Mixture for 90 minutes to 90 ° C (± 1 ° C), then cools down to 70 to 75 ° C while stirring, sets 0.1% Phenol, calculated on the product, is added and the mixture is stirred for a further 15 minutes at 70 to 75 ° C. This gives 4268 g of a copolymer solution with a solids content of 33.3% and a viscosity of 33 poises at 25 ° C (Viscometer Brockfield LVF No. 3 spindle / 12 rpm).

38 g of pickled calf skin are placed in a bottle and 27 g of the copolymer solution prepared above, 3.8 g of common salt, 76 cm ^{3 of} water are added.

The bottle is closed, shaken in a vibrating machine for 24 hours, then 1.5 g of sodium acetate are added, shaken for a further 3 hours and then the tanning liquor is drawn off. The skin is washed thoroughly with water, licked with a mixture of 0.3 g of a commercially available sulfated nipple oil, 0.08 g of neat foot oil in 57 cm ^{3 of} water, shaken for 1 hour, left out, dried and finally finished in the usual way .

An excellent piece of white leather with excellent lightfastness and very good quality is obtained Aging properties.

5 6

Example 2 finished in the usual way and obtained a white leather,

It is produced ^that shows excellent body and color.

Solution A: Example4

105 cm »water, ⁵ there are produced

1.75 g ammonium persulfate;

Solution A: Solution B: _{igo cm3 water;}

50 g methacrylic acid, 30 cm »hydroxylamine solution (1.02 g hydroxyl

13 g of aqueous sulfated sperm oil (10 g of oil). io amine),

26 grams of aqueous sulfated cod oil (20 grams of oil); The solution A is heated to 90 ° C. and then set
add solution B within 40 minutes, stir solution B: 90 minutes at 90 to 95 ° C., then add 1.5 g of am- 90 g of methacrylic acid,

monium hydroxide (28 ° / o NH ₃ ) is added, 15 mi 15 10 g of acrylic acid are stirred;

Groove further at 90 to 95 ° C and leaves under further
Cool to 70 ° C. with stirring. A mixed solution C is obtained:

polymer solution with 35% solids content. The 2.9 g of 35% hydrogen peroxide,

^{Polymer has 50 cm 3 of} water at 25 ° C and 33% concentration,

a viscosity of 70 poises. 20th

23 g of chrome-tanned calf skin are placed in a solution A is heated to 90 ° C, inside a bottle and a mixture of 2.5 g of the 35% tanning agent solution specified above, solutions B and C, is added simultaneously and in portions over a period of 40 minutes Quickly add 0.5 g of 35prodes copolymer and 46 cm ^{3 of} water, add more hydrogen peroxide, stir in a shaker for 90 minutes, 90 minutes at 89 to 92 ° C and keep the mixture, the tanning liquor is then washed off the leather in motion as it cools to around 70 ° C. It is thoroughly worked out and finally finished as in, a solution Example 1 is obtained in 30.5 percent concentration of acidic copolymer, which is in a concentration

The result is an excellently filled, good tration of 33% at 25 ° C. and a viscosity of bleached leather, which has a not retanned 3 ° 35 poisen.

Chrome leather is far superior. It has excellent- You put 41 g of pimpled calf skin into one

Nice lightfastness and aging properties. Bottle and add a tanning solution of 6.9 g

the 30.5 percent copolymer solution, 4.1 g of sodium chloride, 82 cm ^{3 of} water.

Example 3 _{35 The} mixture is then shaken for 18 to 20 hours. The

There are produced ^au ^ ^d ' ^{ese we} ' ^se pre-tanned leather is then in

usually with 9.9 g basic zirconium sulfate

Solution A: tanned, then washed thoroughly and with 1.64 g

160 cm ^{3 of} water, commercially available sulfated nipple oil and 0.41 g

2.0 g of hydroxylamine sulfate, 40 foot oil in 63 cm ^{3 of} water and finally

26 g aqueous solution of sulfated nipple oil prepared in the usual way. The one made in this way

(20 g of oil); Leather shows excellent body and color.

Solution B: Example 5

100 grams of methacrylic acid; 45 _{It is} manufactured

^Solution 8 ^C: Solution A:

3.3 g hydrogen peroxide (30%), _{200 cm3 water;}

50 cm ^{3 of} water. ₁ 3 _gw ä _{ßriges su} ifie _rt it soybean oil (10 g oil)

50 0.25 g lauroyl peroxide; Solution A is heated to 90 ° C, the solution is

gen B and C at the same time and in portions inside solution B:

half of 40 minutes while stirring, quickly pour 50 g of methacrylic acid,

0.7 g RA, put into it, then add 2 g 28 percent 50 cm ³ water,

Ammonia "in 4 cm ^{3 of} _water within a minute, 55 1.5 g of mercaptoethanol. Stir at 90 to 95 ° C for 20 minutes and cool,

also with stirring, to about 70 ° C. The solution A is heated to 90 ° C. and then set

receives the mixed poly- solution B in a concentration of 35% within 45 minutes, gives way

merisat. Viscosity in 33 percent concentration for a further hour a solution of 0.8 g Am-

40 poises at 25 ° C. ^Add 6o monium persulphate in 7 cm ^{3 of} water, stir for 1 hour.

Bottle and mixed with a tanning solution consisting of 34 to 40 ° C the reaction mixture in

from 6.8 g of the above 35 percent mixed polymer movement. Up to 107 g of distillate are stripped in vacuo

solution, 82 cm ^{3 of} water. lat and receives 212 g of a copolymer solution

It is shaken for 3 hours and the tanning liquor 65 with a solids content of approximately 28% is drawn. At 25 ° C and

and washes the leather thoroughly. One licks with a concentration of 33%, the mixed poly-

41 g of commercially available suifed neat foot oil and 0.41 g of merisate have a viscosity of 34 poises.

Oil in 63 cm ^{3 of} water. The leather is made into 30 g of chrome-tanned calf skin

into a bottle and add a tanning solution of 1.8 g of the mentioned 28 percent solution of the copolymer, 60 cm ^{3 of} water.

It is shaken for 2 hours, the tanning liquor is drawn off, the piece of leather is rinsed and a solution of 1.2 g of quebracho powder and 60 cm ^{3 of} water is added.

It is shaken with it for 2.5 hours, a liquor is drawn off, washed thoroughly and licked with 0.6 g of sulphonated nipple oil in 45 cm ^{3 of} water and finished in the usual way. An excellent, light-colored piece of leather with superior lightfastness, good fullness and roundness is obtained.

Example 6

The method of Example 4 is used to prepare mixed polymer solutions composed of acid and sulfated oil with approximately 30% solids content by replace the cod oil one by one with

a) sulfated castor oil,

b) sulphurized nipple oil,

c) sulfated sperm oil,

d) sulfated soybean oil.

tanning or pretanning in the same way and with the same beneficial results that are used in the Examples 1 to 5 are given.

Example 7

The procedure of Example 4 is repeated, but using a solution B consisting of 75 g ίο consists of methacrylic acid and 25 g of acrylic acid.

The possible uses and the results are the same as in Example 6.

Examples

The procedure of Example 4 is repeated, but replaces one after the other in solution A sulfated cod oil through

a) sulfated castor oil,

b) sulphurized nipple oil,

c) sulfated sperm oil,

d) sulfated soybean oil.

Each of the copolymers obtained in this way The uses and the results Merisate solutions are suitable for tanning, post-processing are the same as in example 6.

409 645/16

Claims (2)

1 2 that it would not significantly modify the properties of the copolymers ρ "h ■. P 'A process for the production of copolymers by polymerizing acrylic 1. A process for the preparation of mixed poly- ⁵ acid together with polymerisable esters in merizates by polymerisation of acrylic acid, presence of polymerisation catalysts and together with polymerisable esters in optionally chain terminators found, which presence of polymerisation catalysts and is characterized in that 80 to 90 weight optionally chain terminators, characterized percent of acrylic acid, methacrylic acid or mixtures in that 80 to 90 weight ¹⁰ of both percent together with 20 to 10 weight percent acrylic acid, methacrylic acid or overall of an unsaturated Sulfierungsprodukts a tierimische both together see or 20 to 10 weight vegetable oil in an aqueous medium in percent of an unsaturated sulfonation product in the presence of water-soluble catalysts polymerieines an animal or vegetable oil in an aqueous solution. Medium in the presence of water-soluble catalysis * 5 The acid component is preferably only gates are polymerized. Methacrylic acid or a mixture of methacrylic 2. Use of copolymers, heric acid with up to 25% acrylic acid applied. The set according to claim 1, as 5 to 40 weight sulfated oil in the copolymer should preferably be a percent solution in water for tanning, pre-10 to 25, in particular 10 to 50 weight percent, tanning or retanning of pelts and ² ° calculated on the acid component . In particular skinning. whose oil component should be about 15 to 20% of the Make up monomer weight. The oil component is said to have only been sulfated so far be that not all double bonds of the 25 product have been eliminated. The sulphonation can therefore have been carried out in such a way that there is still a double bond remains in the oil. When the oils are still free It is known that various pelts or hides contain hydroxyl groups, the sulfonation can be limited to the hydroxyl group with the help of polyacrylic acid, polymethacrylic and all acids or copolymers of these acids can tan 3 ° double bonds unaffected. The sulfielassen. These substances are used as the only tanning but can also include both the hydroxyl groups medium or in combination with a pretanning such as some of the double bonds in the oil, or retanning with other tanning agents, such as olive oil, for example, contains chromium, zircon, natural tannins and as the main component Synthetic glycerine ester of oleic acid, and here the table tanning agents can be used. As a considerable sulphonation on one or two of the three unsaturated disadvantages, cracking of the leathering point in the glyceride molecule containing sulphate groups is often observed, even in cases of difficult lead and two or one of the unsaturated group-greased skins. Preparations that leave a tanning process untouched. Any means and a fatliquoring agent are also suitable, for example another animal or vegetable oil, which is an oil, have the disadvantage that the oil 40 or more glycerides of long-chain unsaturated acids with 12 contain up to 20 carbon atoms,
ruled out. Examples of these oils include bitter almond, The Belgian patent 634 538 relates to the beechnuts, black mustard, candlenut, castor, impregnation of leather, while the inven- Chaulmogra, cod liver oil, corn, cottonseed, bacon, methods according to the invention with a tanning process 45 linseed, menhaden, foot oil, palm kernel, peanut , deals. In addition, in the above-mentioned poppy seeds, bottlenose dolphin oil, pumpkin seeds, rapeseed, gischen patent specification copolymers of 2.5 to 18.5 safflower, seal, sesame, soybean, sperm oil, son mol percent acrylic acid, methacrylic acid and itacon flower oil, tung oil, Walnut oil, whale oil.
acid with esters and alcohols described, while the production of the still partially unsaturated According to the invention, as will be found in more detail below, 50 sulfonation products of these oils are known. Such will be, copolymers from 80 to 90 weight products are also available on the market, percent acrylic acid, methacrylic acid or mixtures The copolymerization is carried out in an aqueous both carried out with 20 to 10 percent by weight of an unseeded medium in which the sulfated oil was added Sulphation product of an animal or, for example, in a concentration of 5 to 15 plants Oil are used. 55 percent by weight, is dissolved. For this purpose, one uses a British patent 887 176 relates to the water-soluble initiator for the polymerization and treatment of pelts and hides with an aqueous, optionally a water-soluble, chain terminator Dispersion of an emulsion polymer from approximately to. An aqueous solution of a chain terminator 95 to 99% methyl methacrylate and about 0.5 can also be dissolved directly in the monomer, up to 5% methacrylic hydroxamic acid. This acid has 60 and in this solution is then in the reaction vessel does not have any carboxyl groups and therefore cannot incorporate the solution of sulfated oil and catalyst Hides and skins react in this way as if mixed. One keeps the solution of sulfated oil and Copolymers that have an acidic function. Catalyst at room temperature or heated it up Even if these copolymers are in the presence of 97 ° C or under reflux even higher and 65 sulfated by small amounts of sodium salts sets the acidic sperm oil alcohols at the desired temperature manufactured as a dispersant to worponente. Mixing begins with the addition of acid there would still be any polymerisation with the unsaturated sulfated oil, grafted or polymerized amount so low, and one obtains the product of the invention, which