CS259494B1 - Mixture for dipped rubber products production - Google Patents

Abstract

The solution relates to a mixture of natural latex and / or synthetic rubber stuffed rubber products K-value polyvinyl chloride 60 to 80, which is effectively dispersed therein. Compared to conventional mineral fillers can be achieved in this way higher filler dosing, lower filler sedimentation in the mixture without affecting the coloring of the products.

Description

The invention relates to a latex-based mixture of natural and / or synthetic rubber for the manufacture of rubber products by coagulation dipping.

Presently, the dipped rubber products are made mostly from a mixture of natural and / or synthetic latex containing the usual vulcanizing and other additives, which may further comprise a filler. The fillers used are mostly of mineral origin. The dosage of these fillers is limited by the tendency to rapid sedimentation and the negative effect on physico-mechanical properties. Especially with higher filler dosing, tensile properties and stiffness are greatly impaired, which is undesirable in terms of both utility properties and manufacturing technology in most dipped rubber products.

The purpose of the invention is to provide a mixture in which the sedimentation of the filler is substantially reduced. For this purpose, a latex composition comprising, in addition to latex of natural and / or synthetic rubber and conventional additives per 100 parts by weight of dry matter, a mixture of 0.1 to 40 parts by weight of a polyvinyl chloride having a K-value of 60 to 80 1 to 5 parts by weight of an ammonium or alkylammonium salt of a polymeric polycarboxylic acid having 1 to 5 carbon atoms in the alkyl and having a molecular weight of 1800 to 2200.

The use of the filler in combination with the ammonium or alkylammonium salt dispersant of the polymeric polycarboxylic acid in the mixture ensures the desired physical-mechanical and other utility properties of the products, without affecting the equipment of the products, while reducing material cost of production. · ^?

In order to further elucidate the invention, the following production examples are set forth.

Example 1

A filler dispersion having the following composition (in parts by weight) was prepared in a ball mill:

polyvinyl chloride having a K-value of 66 50 an alkyl ammonium salt of a polymeric polycarboxylic acid (having 3 carbon atoms in the alkyl having a molecular weight of 2,000) 0.5 distilled water 49.5

Into latex mixture of composition:

natural rubber latex (dry matter 60%) accelerators (zinc alkylthiocarbamates) sulfur ground zinc white transparent antioxidant pigment (dry matter 24%) dispersant (alkylnaphthalenesulfonic acid salt) antifoam silicone emulsion

95.18

0.46

0.74

0.10

0.03

1.11

0.18

0.03

0.03

2.14

distilled water A) was added 6 wt. parts listed dispersion fillers (B) 12 wt. parts listed dispersion fillers C) 24 wt. parts listed dispersion fillers D) 36 wt. parts listed dispersion fillers E) 48 wt. parts listed dispersion fillers

Protective gloves were made from the mixtures prepared in this way. The molds were soaked in coagulation solution (40% ethanolic calcium nitrate solution), then for 90 seconds in the latex mixture. The soak was washed for 10 minutes in cold water, dried for 20 minutes at 80 ° C, cured for 20 minutes at 100 ° C and withdrawn from blocks.

The properties of protective gloves made of mixtures A to E and designed to work with acids and alkalis after completion and after treatment with 40% sulfuric acid and 50% caustic are shown in the following table.

Tensile properties of protective gloves after completion

Mixture Tensile strength in MPa Ductility in% AND 29.8 880 (B) 28.2 866 C 25.2 762 D 18.4 580 E 17.1 640

Tensile properties after exposure in 40% sulfuric acid 50 ° C, 18 hours

AND 26.9 874 (B) 26.0 928 C 23.6 823 D 18.7 707 E 16.4 693 Tensile properties after exposure 50% sodium hydroxide 50 ° C, 18 hours AND 22.6 938 (B) 26.6 925 C 20.8 818 D 15.4 678 E 16.9 667

These results show that a high filler dosage can be achieved by meeting the performance requirements of acid and caustic protective gloves. *

In this case, it is preferable to dispense 10 to 20 parts by weight of polyvinyl chloride per 100 parts by weight of the mixture.

Example 2

Into latex mixture of composition (in parts by weight):

natural rubber latex (dry matter 60%) 91.19 dispersant (alkylnaphthalenesulfonic acid salt) 0.27 zinc alkylthiocarbamate accelerator 0.57 sulfur ground 0.57 titanium dioxide 2.40 silicone emulsion 0.03 defoamer 0.03

pigment (dry matter 24 %) 0.10 distilled water 4.84 has been added AND) 6 wt. parts dispersion fillers listed in the example. 1 (B) 12 wt. parts dispersion fillers listed in the example. 1 C) 24 wt. parts dispersion fillers listed in the example. 1

Protective gloves were prepared from the mixtures thus prepared as follows. The blocks preheated to 70 ° C were soaked in a coagulation solution (22% ethanolic nitrate and calcium chloride solution), followed by the said latex mixture (precipitation time 20 s). Subsequently, it was soaked in a suede backing composition and a cotton staple was applied in an air stream. The film thus obtained was dried at 80 ° C for 10 minutes, washed in water for 15 minutes and cured at 110 ° C for 50 minutes. After steaming and stripping, the gloves were dried for 20 minutes at 80 ° C.

In the same way, gloves were made of unfilled mixture for comparison.

Tensile properties of the products upon completion and exposure in detergent compositions are shown in the following table.

Tensile properties of protective gloves after completion

Mixture Tensile strength in MPa Ductility in% unfilled 28.7 1 034 AND 30.2 1 034 (B) 27.5 990 C 22.7 880 Tensile properties after exposure in detergent product ONYX 40 ° C, 72 hours unfilled 20.4 970 AND 22.8 1 010 (B) 22.3 1 012 C 16.9 924

Tensile properties after exposure in detergent JAR extra 40 ° C, 72 hours unfilled 19.3 936

A 22.9 1 006

B, 23.5 990

C 18.7 890

Tensile properties after exposure in detergent product AZUR 40 ° C, 72 hours

unfilled 19.6 942 AND 22.0 982 (B) 21.3 988 C 16.7 896 Tensile properties after exposure detergent BIOMAT 40 ° C, 72 hours unfilled 20.3 948 AND 21.3 966 (B) 21.6 994 C 16.5 885

The above results show that the resistance of the articles of the blend filled with polyvinyl chloride to the action of detergent and detergent is higher than that of the products of the blend.

Example 3

Into latex mixture of composition (in parts by weight):

chloroprene latex (dry matter 58%) 84.37 natural rubber latex (dry matter 60 i) 4.19 zinc oxide 2.82 sulfur colloidal 0.32 accelerator (zinc alkylthiocarbamate) 0.63 antioxidant 1.02 *

dispersant (alkylnaphthalenesulfonic acid salt) 0.18 titanium dioxide 0.37 pigment (24% solids) 0.34 polyvinyl alcohol (16% solids) 0.37 stabilizer (aromatic polyglycol ether) 0.08 distilled water 5.31 was added A) 6 wt. parts of the filler dispersion referred to in Ex. 1 B) 12 wt. parts of the filler dispersion referred to in Ex. 1

Two-layer protective gloves were made from the mixtures prepared in this way by coagulation dipping. The above chloroprene blend was used to form a glove top layer that provides the desired chemical resistance. The inner layer of the gloves consists of a mixture of natural rubber latex, which can also be filled with polyvinyl chloride.

Tensile properties of the products after completion and exposure in transformer oil and diesel are shown in the following table.

Tensile properties of protective gloves after completion

Mixture

Tensile strength in MPa

Elongation at break% in% 26.4

A 24.7

B 25.8

Tensile properties after exposure to diesel 23 ° C, 18 hours

926

843

870 unfilled

AND

(B)

11.5

15.0

16.9

715

720

760

Tensile properties after exposure in transformer oil ° C, 18 hours unfilled 14.7 A 14.8 B 15.0

705

720

735

These results indicate that gloves, the protective layer of which is filled with polyvinyl chloride, have a higher resistance to the effects of diesel and oils.

The compositions according to the invention can also be used in other dipped rubber products, such as in the manufacture of air bladders for balls, bathing caps, protective shoe covers and the like.

Claims (1)

OBJECT OF THE INVENTION * Mixture for the manufacture of dipped rubber products containing latex of natural and / or synthetic rubber containing vulcanizing additives or activators, stabilizers, antioxidants or pigments, characterized in that it contains, per 100 parts by weight of dry matter, a mixture of 0,1 to 40 parts by weight of polyvinyl chloride % to 80 and 0.1 to 5 parts by weight of an ammonium or alkylammonium salt of a polymeric polycarboxylic acid having from 1 to 5 carbon atoms in the alkyl having a molecular weight of from 1800 to 2200.