WO2022073488A1 - High wear resistance all-steel radial tire tread rubber - Google Patents

Abstract

The present disclosure relates to a high wear resistance all-steel radial tire tread rubber. The tread rubber comprises the following components in parts by weight: 70 to 90 parts of cis 1,4-polyisoprene rubber, 10 to 30 parts of butadiene rubber, 3 parts of carbon nanotube or 10 to 40 parts of carbon nanotube/butadiene pre-dispersed master batch, and 40 to 50 parts of super abrasion furnace black. Beneficial effects of the tread rubber in the present disclosure include excellent wear performance, cut resistance and heat conductivity, and significantly extended service life.

Description

A highly wear-resistant all-steel radial truck tire tread compound technical field

The invention relates to a high wear-resistant all-steel truck radial tire tread compound.

Background technique

With the rapid development of my country's highways and the enforcement of the new national standard, my country's transportation industry will be further upgraded. In the future, the failure mode of tires will be more changed from puncture to tread wear, and the requirements for tires will be lower. Rolling resistance, better wear resistance and longer mileage. At present, in the tread formulation of all-steel radial truck tires used on highways, the raw rubber system usually adopts natural rubber with better comprehensive performance or some butadiene rubber with excellent wear resistance, and the reinforcement system adopts small particle size, Super wear-resistant carbon black with large specific surface area.

technical problem

The current tread formula has room for further improvement in terms of adapting to the high wear resistance required by highway roads. On the one hand, increasing the content of cis-butadiene rubber in the formula by a large proportion can improve the wear resistance of the tire tread. The ability to tie and resist chipping and falling blocks has been reduced. On the other hand, the super wear-resistant carbon black with small particle size and large specific surface area has the disadvantages of not easy to disperse, increased heat generation, decreased physical and mechanical properties, and accelerated aging while enhancing the reinforcing effect with rubber, thereby reducing tire pressure. service life.

technical solutions

In view of the above-mentioned deficiencies of the prior art, the present invention provides a high wear-resistant all-steel radial truck tire tread compound. The tread compound can significantly improve the wear performance, cutting resistance, rolling resistance and thermal conductivity of the tread.

A high wear-resistant all-steel truck radial tire tread rubber, the raw material composition of the tread rubber comprises by weight: 70-90 parts of cis-1,4-polyisoprene rubber, 10-30 parts of cis-butadiene rubber , 3 parts of carbon nanotubes or 10-40 parts of carbon nanotube/butadiene rubber pre-dispersed masterbatch, 40-50 parts of super wear-resistant carbon black.

Further, the raw material composition of the tread rubber also includes by weight: 1 part of antioxidant 4020, 1 part of antioxidant RD, 1 part of microcrystalline wax, 2 parts of stearic acid, 3.5 parts of zinc oxide, 1.5 parts of sulfur, 1 part booster.

Further, the carbon nanotube/cis-butadiene rubber pre-dispersed masterbatch is prepared by blending carbon nanotubes, neodymium-based cis-butadiene rubber with a cis content greater than 96%, an activator and a dispersing aid.

Further, the carbon nanotubes are single-walled or multi-walled carbon nanotubes, with a diameter of 5-50 nm, a length of 0.01-50 μm, and a purity greater than 95%.

Further, the weight ratio of the carbon nanotubes, neodymium-based butadiene rubber, activator and dispersing aid is 1:(5-30):(0.1-5):(0.5-10).

Further, the dispersing aid is one of stearic acid and stearate.

Further, the activator is one of silanes, titanate coupling agents, and isocyanates.

Further, the cis-butadiene rubber is a high-cis synthetic rubber with a cis content>96%.

Further, the super wear-resistant carbon black has an iodine absorption value above 110 g/kg, a DBP absorption value above 115×10 ^-5 m ³ /kg, and a nitrogen adsorption specific surface area above 130×10 ³ m ² /kg.

beneficial effect

The tread rubber of the invention has excellent wear performance, cutting resistance and thermal conductivity, and the service life is remarkably prolonged.

Embodiments of the present invention

The invention obtains an all-steel truck radial tire with high specific surface area, high structure and super wear-resistant carbon black. Its tread is composed of the following components: a cis-1,4-polyisoprene rubber, a cis-butadiene rubber with a cis content greater than 96%, a carbon nanotube or carbon nanotube/cis-butadiene rubber pre-dispersed Masterbatch, and a super wear-resistant carbon black with an iodine absorption value greater than 110 g/kg, a DBP absorption value greater than 115×10 ^-5 m ³ /kg, and a nitrogen adsorption specific surface area greater than 130 × 10 ³ m ² /kg.

Among them, the carbon nanotube/cis-butadiene rubber pre-dispersed masterbatch is prepared by adding activator and dispersing aid raw material when carbon nanotubes and neodymium-based cis-butadiene rubber with a cis content greater than 96% are mechanically blended in an open mill or an internal mixer. It can be prepared by site modification, which can significantly improve the dispersion of carbon nanotubes in rubber, and can be carried out on existing production equipment, which is efficient and environmentally friendly. The carbon nanotubes are single-walled or multi-walled carbon nanotubes, with a diameter of 5-50 nm, a length of 0.01-50 μm, and a purity of more than 95%. The tread compound has excellent wear performance, cut resistance and thermal conductivity, and the service life is significantly extended.

A highly wear-resistant all-steel radial truck tire tread compound, the mixing of which can be accomplished by a method known to those skilled in the rubber mixing field. Typically, for example, the components are mixed in at least two stages, ie at least one non-productive mixing stage followed by a productive mixing stage. The rubber and polymer resins are compounded in one or more non-productive compounding stages.

Example 1

Tread compounds of the compositions specified in Table 1 were prepared in a BR Banbury mixer using two separate feed mixing stages, ie, a non-productive mixing stage and a productive mixing stage. In the non-productive stage, the mixing is carried out for about 2-3 minutes, until the rubber temperature reaches 160 °C, that is, it is completed. The kneading time in the productive stage is the time until the rubber temperature reaches 115°C.

The tread compounds are referred to herein as sample a, sample b, sample c, sample d, sample e. Sample a is used here as a control sample, ie, no optimized filler dosage was used in the filler system.

All samples were cured at about 151°C for about 30 minutes. Table 2 presents the apparent and physical properties of the vulcanized samples a-e.

Table 1 Example 1 Each raw material component of tread rubber

Table 2 Example 1 tread compound performance table

Example 2

Tread compounds of the compositions specified in Table 3 were prepared in a BR Banbury mixer using two separate feed mixing stages, ie, a non-productive mixing stage and a productive mixing stage. In the non-productive stage, the mixing is carried out for about 2-3 minutes, until the rubber temperature reaches 160 °C, that is, it is completed. The kneading time in the productive stage is the time until the rubber temperature reaches 115°C. Among them, the carbon nanotube/cis-butadiene pre-dispersed masterbatch is prepared by in-situ modification by mechanical blending, and then added to the internal mixer for mixing in the non-productive stage.

The tread compounds are referred to herein as Sample A, Sample B, Sample C, Sample D, Sample E. Sample A is used here as a comparative sample, ie, the optimized rubber compounding was not used in the tread compound.

All samples were cured at about 151°C for about 30 minutes. Table 4 presents the physical properties of vulcanized samples A-E.

Table 3 Each raw material component of example 2 tread rubber

Table 4 Example 2 tread compound performance table

Example 3

Tread compounds of the compositions specified in Table 5 were prepared in a BR Banbury mixer using two separate feed mixing stages, ie, a non-productive mixing stage and a productive mixing stage. In the non-productive stage, the mixing is carried out for about 2-3 minutes, until the rubber temperature reaches 160 °C, that is, it is completed. The kneading time in the productive stage is the time until the rubber temperature reaches 115°C. Among them, the carbon nanotube/butadiene rubber pre-dispersed masterbatch is prepared by in-situ modification by mechanical blending, and then added to the internal mixer for mixing in the non-productive stage.

The tread compounds are referred to herein as Sample 1, Sample 2, Sample 3, and Sample 4. Sample 1 is used here as a comparative sample, ie, the optimized rubber compounding was not used in the tread compound.

All samples were cured at about 151°C for about 30 minutes. Table 6 presents the physical properties of vulcanized samples 1-4.

Table 5 Each raw material component of example 3 tread rubber

Table 6 Example 3 tread compound performance table

Wherein the above-mentioned carbon nanotube/cis-butadiene pre-dispersed masterbatch is specifically as follows: the carbon nanotube/cis-butadiene pre-dispersed masterbatch of the composition as specified in Table 7 is prepared in an open mill or an internal mixer, and cis-butylene is added successively in the preparation process. Butadiene rubber, activator, dispersing aid, carbon nanotube.

The premix is referred to herein as sample ①, sample ②, sample ③, sample ④, sample ⑤. Sample ① is used here as a control sample, ie, the optimal mixing ratio was not used in the premixed system.

Table 8 gives the apparent properties after all premixes were completed.

Table 7 Each raw material component of the tread rubber of Example 4

sample	①Comparative sample	Sample ②	Sample ③	Sample④	Sample⑤
Pure carbon nanotubes (single-wall or multi-wall carbon nanotubes)	1.0	1.0	1.0	1.0	1.0
Butadiene rubber	1.0	5.0	20.0	5.0	20.0
activator				1.0	0.5
dispersing aid				5.0	2.0

Table 8 The apparent quality of tread rubber in Example 4

These results show that the use of carbon nanotube masterbatch pre-dispersed with butadiene rubber in the tread rubber can significantly improve the wear performance, cut resistance, rolling resistance and thermal conductivity of the tread.

Industrial Applicability

The present invention may be summarized in other specific forms that do not depart from the spirit or main characteristics of the invention. Therefore, no matter from which point of view, the above-mentioned embodiments of the present invention can only be regarded as the description of the present invention and cannot limit the present invention. The claims indicate the scope of the present invention, but the above-mentioned description does not indicate the scope of the present invention. Therefore, any changes within the meaning and scope equivalent to the claims of the present invention should be construed as being included in the scope of the claims of the present invention.

Claims (9)

1. A high wear-resistant all-steel radial truck tire tread rubber, characterized in that the raw material composition of the tread rubber comprises by weight: 70-90 parts of cis-1,4-polyisoprene rubber, cis-butadiene rubber 10-30 parts, 3 parts of carbon nanotubes or 10-40 parts of carbon nanotube/butadiene rubber pre-dispersed masterbatch, 40-50 parts of super wear-resistant carbon black.
2. The high wear-resistant all-steel radial truck tire tread compound according to claim 1, wherein the raw material composition of the tread compound further comprises by weight: 1 part of antioxidant 4020, 1 part of antioxidant RD, 1 part of antioxidant parts microcrystalline wax, 2 parts stearic acid, 3.5 parts zinc oxide, 1.5 parts sulfur, 1 part accelerator.
3. The high wear-resistant all-steel radial truck tire tread compound according to claim 1, wherein the carbon nanotube/cis-butadiene rubber pre-dispersed masterbatch is prepared by mixing carbon nanotubes and cis-butadiene rubber with a content of more than 96%. It is prepared by blending neodymium-based butadiene rubber, activator and dispersing aid.
4. The high wear-resistant all-steel radial truck tire tread compound according to claim 1, wherein the carbon nanotubes are single-walled or multi-walled carbon nanotubes, with a diameter of 5-50 nm, a length of 0.01-50 μm, and a purity greater than 95%.
5. The high wear-resistant all-steel radial truck tire tread compound according to claim 1, wherein the weight ratio of the carbon nanotubes, neodymium-based butadiene rubber, activator and dispersing aid is 1:(5- 30): (0.1-5): (0.5-10).
6. The high wear-resistant all-steel radial truck tire tread compound according to claim 1, wherein the dispersing aid is one of stearic acid and stearate.
7. The high wear-resistant all-steel radial truck tire tread compound according to claim 1, wherein the activator is one of silanes, titanate coupling agents, and isocyanates.
8. The high-wear-resistant all-steel radial truck tire tread compound according to claim 1, wherein the cis-butadiene rubber is a high-cis synthetic rubber with a cis content >96%.
9. The high-wear-resistant all-steel radial truck tire tread compound according to claim 1, wherein the super-wear-resistant carbon black has an iodine absorption value of more than 110 g/kg and a DBP absorption value of 115 × 10 ^-5 m ³ /kg or more, and the nitrogen adsorption specific surface area is more than 130×10 ³ m ² /kg.