Abrasion resistance characterizes the ability of the vulcanizate to resist material loss due to surface damage under the action of friction.
The abrasion of rubber mainly has the following three forms:
Wear and tear
2. Fatigue wear
3. Curl abrasion
The abrasion resistance of vulcanizates is related to tensile strength, tensile stress, tear strength, fatigue performance, and viscoelastic properties.
Constant elongation stress has different effects on different types of abrasion. When the constant elongation stress is high, the convex surface on the friction surface has a small depth of depression into the rubber, strong resistance to deformation, small friction coefficient, and high rigidity of the rubber surface, which is not easy to wrinkle Cause curl, wear
Loss of wear and curl wear are favorable.
Increasing the elasticity of the vulcanizate will also increase the wear resistance.
· Effects of gum types:
* The wear resistance of vulcanized rubber in general-purpose diene rubber is as follows:
* Butadiene rubber> Solvent polystyrene butadiene rubber> Milk polystyrene butadiene rubber> Natural rubber> Isoprene rubber
The abrasion resistance of butadiene rubber vulcanizate increases with the content of cis chain links (1,4 structure).

* Styrene rubber has lower elasticity, tensile strength and tear strength than natural rubber, but it is better than natural rubber.
The abrasion resistance of styrene-butadiene rubber increases with increasing molecular weight.

The nitrile rubber vulcanizate has better abrasion resistance than isoprene rubber, and its abrasion resistance increases with the increase of the acrylic content. The carboxylated nitrile rubber has good abrasion resistance.

The abrasion resistance of ethylene-propylene rubber vulcanizates is comparable to that of styrene-butadiene rubber.As the Mooney viscosity of the raw rubber increases, its abrasion resistance also increases.

The abrasion resistance of butyl rubber vulcanizates is similar to that of isoprene rubber at 20 degrees; but when the temperature rises to 100 degrees, the abrasion resistance decreases sharply. When butyl rubber is mixed at high temperature, the abrasion resistance of vulcanizates The abrasion is significantly improved.

The vulcanizate based on chlorosulfonated polyethylene has high abrasion resistance and abrasion resistance at high temperatures.

Acrylic rubber-based vulcanizates are slightly worse than nitrile rubber vulcanizates

Polyurethane rubber is the best abrasion resistance of all rubbers at normal temperature. The abrasion resistance drops sharply at high temperatures.

Rubber type: Abrasion / MG
PUR 0.5-3.5
NBR 44
CR: 280
NR 146
SBR 177
IIR 205

· Relationship between vulcanization system and abrasion resistance
The abrasion resistance of vulcanizate has a maximum value with the increase of the amount of vulcanizing agent. The optimal vulcanization degree when the abrasion resistance reaches the optimal state decreases with the increase of the amount of carbon black and the improvement of the structure.

Generally the sulfur + accelerator CZ system has better wear resistance.
DTDM + sulfur (less than 1.0 parts) + accelerator NOBS system vulcanizate abrasion resistance and other mechanical properties are better
When sulfur + CZ (main accelerator) + TMTD + DM + D (secondary accelerator) is used to cure natural rubber, the amount of sulfur is 1.8-2.5 parts.
The rubber compound mainly based on butadiene has a sulfur content of 1.5-1.8 parts.

· Relationship between filling system and abrasion resistance
In general, the abrasion resistance of vulcanizates increases as the carbon black particle size decreases and surface activity and dispersibility increase.
Adding 50 parts by mass of vulcanizate of SAF and ISAF carbon black to EPDM rubber compound, its abrasion resistance is doubled than that of the same amount of FEF carbon black.
The best filling amount of various rubbers: BR》 oil-filled SBR》 oil-free SBR》 IR》 NR

White carbon black treated with a silane coupling agent can also improve the abrasion resistance of vulcanizates.

· Effect of softener on the abrasion resistance of vulcanized rubber
Softeners are usually added to rubber compounds to reduce the abrasion resistance of vulcanizates.
The vulcanizate of oil-filled styrene-butadiene rubber (SBR-1712) has abrasion resistance 1-2 times higher than that of SBR-1500.
In general, the use of aromatic oils in natural rubber and styrene-butadiene rubber has less loss of wear resistance.

· Relationship between wear resistance and protection system

Under the condition of fatigue wear, the addition of an antioxidant to the rubber compound can improve the wear resistance of the vulcanizate.
As the antioxidant, it is best to choose a variety that can prevent fatigue and aging. P-phenylenediamine antioxidants with excellent anti-odor and aging, especially 1019NA, have outstanding effects. Antioxidants H and DPPD also have the effect of preventing fatigue and aging, but their use is limited due to blooming.
Antioxidant D also has the effect of preventing fatigue aging on NR. It does not work for SBR.
In SBR, the antioxidant IPPO has a protective effect on its fatigue and aging.
In addition to N010NA, UOP588 (6PPD), DTPD, DPPD / H, etc. also have certain effects to prevent fatigue and aging.