SU802316A1 - Butadiene rubber-based rubber mixture - Google Patents

Description

The invention relates to the rubber industry, in particular, to the development of a rubber compound based on butadiene rubber. , o Known rubber mixture based on ’butadiene rubber (SKD) with a Mooney viscosity of 40-60 units. and a molecular weight of up to 500 thousand, including> caustic cis-polybutadiene, sulfur, s. sulfenamide, stearin, zinc oxide and carbon black, with a ratio of components, respectively (mass parts) of 75: 25: 1.75: 1: 1.5: 4: 80 [1].

However, the rubbers from this mixture have reduced physical and mechanical properties.

The purpose of the invention is to increase the physico-mechanical properties of rubber from this mixture.

This goal is achieved by the fact that the rubber mixture based on butadiene rubber, including liquid cis-polybutadiene, sulfur, sulfenamide, stearin, zinc oxide and carbon black, contains butadiene rubber * 5 mol%. weighing 640-800 thousand and a Mooney viscosity of 102-114 units. in the following ratio of components, parts by weight:

Butadiene rubber 85-65.

Liquid cis-polybutadiene 15-35 30

Sulfur 1.5-2

Sulfenamide1-1.5

Stearin 1 ~ 2

Zinc Oxide 3-5

Carbon black 70-90

PRI me R 1. In the composition, parts by weight liquid cis-polybutadiene - 15.0, sulfur 1.5, sulfenamide C - 1.0, stearin 2.0, zinc oxide - 5.0, carbon black - 70.0, 85.0 parts by weight are added. high molecular weight cis-butadiene rubber with a molar mass of 640 thousand · (viscosity 102 units Mooney). The manufacture of the rubber mixture is carried out according to the technology adopted in the rubber industry - either in a rubber mixer, or on rollers.

. The properties of the rubber from the known and proposed (15 l'ass.h. liquid cis-polybutadiene and 85 parts by weight of high molecular weight rubber) are presented in

tab. 1. Table 1 Indicator Prototype The proposed mixture 1 2 3

Conditional stress at 300% elongation, MPa 7.5 13.5

Continuation of the table. 1'

< 2 3 ' Tensile strength, MPa 14.2 21.5 Resistance diro, kN / m 28 52 Abrasion on World-1, m ^ / TJ 25 32

Example 3. The composition, parts by weight: liquid polybutadiene - 25, sulfur - 1.8, zinc oxide - 5, stearin - 1.5, carbon black - 80.0, high molecular weight cis-polybutadiene - 75.

Physico-mechanical indicators of rubber from the proposed (25 parts by weight of liquid cis-polybutadiene and 75 SKD with a mol. Mass of up to 500 thousand) and known mixtures are given in table. 3

Table 3

Crack propagation resistance, thousand, cycles _______ 48________60_____

Example ΣΊ In the composition, parts by weight liquid cis-polybutadiene - 35.0, sulfur 2.0, sulfenamide C - 1.5, zinc oxide - 8.0, stearin - 1.0, carbon black - 90.0

6-5.0 parts by weight of high molecular weight cis-butadiene rubber with a molar mass of 20

800 thousand (viscosity more than 114 units of Mooney).

The manufacture of the mixture is described in example 1.

Physico-mechanical properties of 25 rubbers from the known and proposed (35 parts by weight of liquid cis-polybutadiene and 65.0 parts by weight of high molecular weight rubber) of the mixtures are given in Table 2.

table 2 thirty Indicator Prototype Proposed mix Conditional stress at 300% elongation, MPa 7.1 15.9. 35 Tensile strength, MPa 13.8 21.7 40 Abrasion on Mir-1, m ^d / TJ 31 43 Resistance to crack growth, thousand cycles 2,5 25 45

The proposed composition containing liquid polybutadiene, carbon black and other commonly used additives provides, through the use of cis-polybutadiene with a molar mass of 640-800 thousand (Mooney viscosity of 102-114 units), an increase in the physical and mechanical properties of rubber: increasing 5, conditional stress at 300% elongation, tear resistance, tearing, wear resistance, and crack growth resistance are provided.

Indicator

Proposal Prototype Mix

Conditional stress at 300% elongation, MPa 14.2 4.8 Tensile strength, MPa 20,4 13,2 Abrasion on World-1, m ^ / TJ 41 63 Resistance L crack growth, thousand cycles 36 14.8

As can be seen from the table. 1-3, the rubber from the proposed mixture in comparison with the prototype are characterized by improved physical and mechanical properties.

Claims (1)

Claim The rubber mixture based on butadiene rubber, including liquid cis-polybutadiene, sulfur, sulfenamide, stearin, zinc oxide and carbon black, characterized in that, in order to increase the physico-mechanical properties of the rubbers from this mixture, the latter contains butadiene rubber with molar mass 640-800 thousand and a Mooney viscosity of 102-114 units, with the following ratio of components, parts by weight: Butadiene rubber 85-65 Liquid cis-polybutadi en 15-35 Sulfur 1,5-2 Sulfenamide 1-1.5 Stearin 1-2 Zinc oxide 3-5 Carbon black 70-90