SU992537A1 - Vulcanizable rubber stock for producing porous rubbers - Google Patents

Description

The invention relates to the industry of artificial leather and film materials and can be used to obtain porous rubbers intended for the bottom of shoes, characterized by EX with slight shrinkage, uniform, finely porous structure, and an improved complex of physical and mechanical properties.

Porous synthetic materials for the bottom of the shoe compare favorably with natural leather in their operational and heat-protective properties. Therefore, they are increasingly used and are the most common and promising materials.

However, a significant drawback of porous rubbers is their ability to change their size over time as a result of relaxation of stresses. 1 3f, dich appeared during the formation of a porous structure, the so-called shrinkage effects. The presence of a large shrinkage in the porous solution They create significant difficulties in shoe technology due to warping of shoes, reducing the strength of glue fastening. To reduce the time required to set

a stabilized state of porous rubber, in which the geometrical dimensions practically do not change much, the natural shrinkage process is artificially accelerated by using various technological methods: heating the vulcanized material at a certain temperature and duration of the thermoing process (working) , does not provide the necessary shrinkage values and physicomechanical parameters of rubbers with a density of 0.3–0.5 g / cm; processing of rubbers in the electric field of high-frequency currents allows reducing it rubbers shrinkage value at a density of 0.5 - 0.7 g / cm (however, this method is low efficiency, does not provide uniformity

20 heating the material throughout the volume, ineffective in the case of rubber processing with a density of 0.3-0.5 g / cm); It is possible to reduce the shrinkage of rubber by pre-dividing 25 blocks before heat treatment. (The use of this technique requires a decrease in the temperature of heat treatment of rubber, which leads to an increase in shrinkage and deterioration of 30 the appearance of rubber after heat treatment due to warping. After heat treatment and cooling, additional rubber spitting is necessary in order to level the surface due to unevenness of surface the area of the plate. Practical use in industry this technique has not been found). Closest to the present invention is a vulcanizable rubber compound 2 for producing porous 10 rubbers, including high styrene and low rolling styrene butadiene rubbers, a dye, a softener, a poro-generator, an accelerator and a vulcanization activator, sulfur and a filler. | 5 for example, at a ratio by weight: 35: 10: 1; 5: 3: 1: 2: 1: up to 100. Reduction of shrinkage of porous rubbers with a density of 0 | 3-0,5 g / cm is carried out by heat treatment in a shrinkage tube - “re under vacuum, with the shrinkage of evacuated rubbers three times and below the shrinkage of rubbers of mass production. However, it is practically impossible to apply this technique in npoiuKiOimeHHocTH due to the lack of equipment, the complexity of the instrumentation to create the required vacuum, the need for 24-48 h of prog, and the laying of rubber after vulcanization before thermal vacuum. The purpose of the invention is to reduce the duration and the length of the shrinkage, as well as the elimination of the vacuum; during heat treatment in the process of rubber shrinkage (with an increase in the complex of physicomechanical parameters: tensile strength, elasticity, tear resistance and multiple folds, deformation, bonding strength of rubber with fabric, resistance to aging). This aim is achieved in that the vulcanizable rubber mixture dd preparing porous rubbers vklyuchascha vysokostirolny and nizkostirolny butadiene rubbers, dye, emollient, porogen vulcanization accelerator, vulcanization activators, sulfur and silica filler, further contains a polychloroprene rubber in the following ratio, wt.% Polychloroprene rubber4-8 High styrene butadiene styrene rubber34-37 Low quality polystyrene butadiene styrene rubber 5-12 Dye of 0.6-2 M gchitel4-6 I am not in the middle of a series of mix- ers of SO, you are just two. 2-4 Cure accelerator 0, 5-1.5 Curing activator1, 5-3 Silica filler Remaining up to 100 Example 1. Rubber composition, wt%, is prepared: Polychloroprene rubber (Nairit A, B, КР, СР) 4-8 High-styrene rubber, (BS-45) 35 Low-grade rubber (SKMS-ZORRP) 8 Dye (soot, pigments) IM mower (oil PN-6, rosin) 5 Blowing agent (CHHZ-21) 3 Vulcanization accelerator (DFG, sulphateshdad) 1. Vulcanization activator (ZnO) 2 Sulfur. 1 Silica filler. Aerosil) Up to 100 The mixture is prepared by mixing the mixer at a temperature higher, Polychloroprene chuk is introduced into the composition of the mixture along with other rubbers in a mixture, and zinc oxide is mined before the mixture is added. The mixture is technological at all stages of processing and is superior to rubber produced by syringe resistance to rubber si and has a smoother surface of the workpieces. The mixture is vulcanized in hydraulic cess at 165-170 ° C under pressure of 160-180 atm for 6-8 minutes. After vulcanization, the rubber is heat treated in a chamber at C for 3 hours. Then, in that chamber at 9 ° C, it undergoes a revolving stage (3 h / and is cooled. After cooling, the rubber blocks to obtain plates of the desired women. 1 Quantitative criterion characterizing the quality of porous rubber The points of view of its shrinkage are the value of the control supplementary water, determined according to the procedure stipulated by GOST 12632-79, and the value of the additional shrinkage of the sample after it has been heated for 10 minutes at, according to GOST 12632-79, the control shrinkage for of grades of porous rubber should not exceed 1.5%. Boundary and intermediate doeirs of polychloroprene rubber, providing a stable positive effect, as well as dosage values, yield 11 (they are outside the proposed range, are given in Table 1. 1 it can be seen that when nairite contains 4-8 wt.h., the shrinkage of porous rubber decreases, and this increases the complex of physicomechanical indicators: breaking strength, dynamic endurance, tear resistance, elasticity, durability of rubber with Kan1Е5Ü, resistance aging aging. At the same time, the optimal content of polychloroprene pod is 5.0 wt.h. Removal of 3.0 wt.h. has not yet had a significant effect on reducing the amount of shrinkage and the nature of the porosity of rubber, and 10.0 wt. reduces the resistance of mixtures to scorch. The data on the change in shrinkage and other physicomechanical parameters of rubber manufactured with and without nairite are shown in time in Table. 2. From the data table. 2 it follows that the duration of shrinkage of rubbers made with nairite is minimal in contrast to the known composition in which Usadas continues to increase with an increase in the time that the rubber remains lying, as a result of which the rubber does not reach a stabilized state. Example 2 Using the same technology (as in example 1) rubber was manufactured using polychloroprene rubbers of various grades in a dosage of 5.0 parts by weight. Physico-mechanical properties of rubber are presented in table. 3. From the data table. 3, it can be seen that general purpose polychloroprene rubbers reduce shrinkage of porous rubbers, sew a complex of strength properties and elasticity, and the adhesiveness of rubbers. With the introduction of polychloroprene rubbers into porous rubber, other positive aspects also emerge: the formation of a very fine-porous, uniform rubber structure; the presence of zamtsevidnoy velvety surface from the side of the lance; uniformity of vulcanization of products throughout the entire massif, which makes it possible to obtain rubber of increased thickness, which, as is well known, is currently a serious problem in the industry, the possibility of obtaining rubbery colors characterized by high dynamic endurance in the absence of low stabilizers, which the industry has Currently, there is no recipe for rubbers containing gYulichls oprenovy rubber, significantly economical. i are known by the low quality of low polymers of polychloroprene rubbers, by reducing the content of zinc oxide, by removing expensive industrial rosin and stabilizers from the recipe. Technical and economic benefits of the proposed object are given in table. 4. As can be seen, the proposed composition with nairite is characterized by a lower value. Controlled shrinkage when eliminating the evacuation during heat treatment of rubber and shortening the length of lay-up after vulcanization. All this leads to a significant zokokicheskom result.

Table 1

Before aging

Strength at break, kgf / cm

Elongation%

Residual elongation,%

E Density, g / cm

Hardness TM-2, used, from the side of the torsion Tear resistance, kgf / cm

Resistance to "tensile stretching,

thousand cycles OB

The strength of gluing rubber with cloth, kgf / cm

Shrinkage at,%, while warming up for 10 minutes

about

Time of scorching j min

After aging (

Strength at break, kgf / cm

Relative extension, ; Residual elongation,% Density, g / cm Hardness for TM-2, conventional unit. Tear resistance, kgf / cm

Resistance to multiple stretching, thousand cycles

The coefficient of aging relative elongation

Aging coefficient for resistance to multiple stretching

52

0.81

0.68 Tensile strength at break, kgf / cm Relative elongation,% TN-2 hardness, used Density, g / cm Tear resistance, kgf / ol Resistance to multiple stretching, thousand cycles Shrinkage,%

Rubber strength, kgf / cm

Relative extension , %

Hardness TM-2, used

Density, g / cm

Tear resistance, kgf / cm

Resistance to repeated stretching, thous.

Gluing strength of rubber with fabric, kgf / cm Shrinkage,%

Tavlitsa 2

Table 3

28 345

28,275

30,382

50 0.45

50 0.47

48 0.44

4.3

5.8

6.2

37.5

 50

50

3.5

6.2

6.0 0.72 0.25 0.12 40464848 0.49 0.480.500.51 5.19.5 38.5 68.370.5-. 100 1,30,4300

Claims (1)

Claim Vulcanizable rubber mixture for the production of porous rubbers, including high-styrene and non-styrene butadiene-styrene rubbers, dye, softener, blowing agent, <vulcanization accelerator, vulcanization activator, sulfur and silica filler, with a lance of 40 so that , in order to reduce the magnitude and duration of shrinkage, as well as eliminate vacuum at. heat treatment in the process of shrinkage of rubbers, it additionally contains polychloroprene rubber in the next. the general 'ratio of components, wt.%: Polychloroprene rubber Styrene butadiene rubber 4-8 34-37 Styrene butadiene rubber Dye Softener Pore former Vulcanization accelerator Vulcanization activator Sulfur ι Silica filler