Polyurethane elastomer (PU) is a new type of material between rubber and plastic, in practical applications as a substitute for the renewal of rubber products, due to the PU has good abrasion resistance (elastomer is the best), high strength (is 3 ~ 5 times the ordinary rubber), high elongation (500% -1500%), high elasticity (load support capacity, vibration damping effect is good), hardness range (Shore A20 ~ Shore D70); and also has oil resistance, acid resistance, alkali resistance, radiation resistance and other excellent properties. A20~Shore D70); and also has oil resistance, acid and alkali resistance, radiation resistance and other excellent properties.

Abrasion resistance
Polyurethane elastomers (PU) have outstanding abrasion resistance and therefore have many important applications where wear is a serious problem, particularly in the transmission belt, mining, and oil and gas industries. In field use and in experimental tests, the abrasion resistance of polyurethane elastomers (PU) clearly outperforms that of many other materials.

PU has excellent abrasion resistance, and the abrasion data for several materials are listed in 1-1, where it is evident that PU is the least abrasive.

Table 1-1 Abrasion values of various synthetics

(Note: Abrasion conditions CS17 wheel, 1000g/rev, 5000r/min, 23°C)

Hardness range
The hardness of PU elastomers ranges from approximately Shore A10 to Shore D80, whereas common rubber hardness ranges are generally in the range of Shore A60 to 100. It is worth noting that PU elastomers have an elongation of 400% to 800% over such a wide range of hardnesses, whereas natural rubber has a maximum hardness of Shore A70 at an elongation of 550%.

Stress/Strain Properties
Polyurethane elastomers (CPU) have high modulus, high tensile strength and high elongation. These properties make polyurethane parts tough and durable, and the tensile strength of PU elastomers is 2-3 times higher than that of natural and synthetic rubber.

Shock absorption
Polyurethane elastomers have much higher load-bearing capacity (including elasticity, high elongation, high strength, long hysteresis time, good damping performance) compared to general rubber with comparable hardness, thus absorbing large amounts of energy during stress-strain, with good damping effect. The combination of this high load-bearing capacity with excellent abrasion resistance and toughness makes polyurethane elastomers very advantageous for use in applications such as anti-vibration mounts for artillery trucks, landing gears for airplanes, automobile bumpers, and industrial rollers. The advantages of polyurethane elastomers are outstanding.

Low vibration
PU belts and multi-groove belts are made of liquid low-pressure infusion, and the whole belt is molded as one piece with better homogeneity, so it is not easy to generate vibration in the process of transmission, which in turn creates a source of vibration and vibration to the beginning of the machine.

Weather resistance
The oil resistance of PU elastomer is better than nitrile rubber, and the weathering resistance is better than natural rubber and other synthetic rubber. In terms of hydrolysis resistance, acid and alkali solution corrosion resistance, polyether PU elastomer is better than polyester PU elastomer; in addition, PU elastomer has excellent ozone resistance and ray resistance, which has special use in the aerospace industry.
7. Other physical properties

Generally speaking, all elastomers with hardness below Shore A75 have similar compression deformation characteristics. However, PU elastomers remain elastic when the hardness is above Shore A85 or 85, which is a characteristic that is not found in other elastomers. Therefore, PU elastomers have a high load-supporting capacity and good shock absorption.

PU elastomer's shock absorption performance is very good, so its products can have better shock absorption, high tensile strength and elongation, and thus load support capacity, compared with other rubber can save material. Such as high-grade automobile bumpers, steel rollers, wear-resistant pipelines, pump liners, etc. must be used PU elastomer, other materials are very difficult to replace.

Comprehensively speaking, PU material belt is less likely to cause contamination of the machine parts, especially suitable for various harsh environments, such as pressure-free room environment under the transmission and conveyor belt needs, especially in the pressure-free registration for the hundred or even to the environment of the thousands of levels, the need to use PU material, can be the transmission belt components wear produced by the micro-pressure to a minimum, in addition, the rubber material contains carbon, in the abrasion state will be dispersed all over the place, there will be a cause of the product circuit In addition, rubber material contains carbon, which will fly around in the abraded state, causing the suspicion of short circuit and more serious pollution; in applications such as CNC machinery transmission mechanism that needs to be resistant to oil and grease contamination, and small pulley diameter transmission, PU material has very good performance.