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Polyurethane elastomer has many valuable properties and wide application fields. In the application research, in addition to the correct selection of formulation according to the use environment, it is also necessary to select the appropriate hardness according to the stress situation of the products in use....
Mildew resistance of polyurethane Polyether type polyurethane has good resistance to mildew, and the test grade is 0 ~ 1, that is, no mildew or basically no mildew. However, polyester type polyurethane (including polycaprolactone) is not resistant to mildew, and the test result is...
Electrical properties The electrical insulation performance of polyurethane elastomer is better at room temperature, which is roughly equivalent to the level of chloroprene rubber and phenolic resin. Because it can be cast or thermoplastic, it is often used for filling and sealing of electrical components,...
The effect of polyurethane elastomer on alternating stress shows obvious hysteresis. In this process, part of the energy of the external force is absorbed by the internal friction of the elastomer molecules, which is converted into heat energy. This property is called the vibration absorption...
Polyurethane elastomers have good low temperature properties, mainly in the brittleness temperature is generally very low (- 70 ~ - 50 ℃), and some formulations (such as PCL-TDI-MOCA) are not even brittle at lower temperature. At the same time, a few varieties (such as PTMG-TDI-MOCA) have good low temperature...
Heat and oxidation resistance of polyurethane Polyurethane elastomer has good heat resistance in inert gas (such as nitrogen), oxygen resistance and ozone resistance at room temperature, especially polyester type. But high temperature and oxygen can accelerate the aging process of polyurethane. The upper...
Water resistance of polyurethane Water resistance polyurethane elastomer has good water resistance at room temperature, and will not have obvious hydrolysis within one or two years, especially polybutadiene type, polyether type and polycarbonate type. Through strengthening water resistance test and...
Polyurethane elastomer, especially polyester polyurethane elastomer, is a kind of strong polar polymer material. It has little affinity with non-polar mineral oil, and is almost free from erosion in fuel oil (such as kerosene, gasoline) and mechanical oil (such as hydraulic oil, engine oil, lubricating oil,...
The wear resistance and friction coefficient of polyurethane elastomer are outstanding. Its wear value is generally in the range of 0.03-0.20m m 3/m (Akron wear), which is much smaller than other polymer materials, 3-8 times better than natural rubber, and the actual use effect is often better. The wear...
Mechanical properties of polyurethane Polyurethane elastomer has good mechanical properties, such as good young's modulus, tensile strength, tear strength and load capacity. Young's modulus and tensile strength Within the elastic limit, the ratio of tensile stress...
Photostability and radiation resistance of polyurethane Polyurethane synthesized from aromatic isocyanate (such as TDI and MDI) is easy to oxidize and turn yellow when exposed to ultraviolet light, which is caused by the bridge bond structure of aromatic biuret. Under UV irradiation, it is...
The flexibility of polymer molecules is the reason of high elasticity. However, due to the large number of polar groups in the molecular structure of polyurethane elastomers, the large molecular internal force and intermolecular force, together with other factors that may hinder the free rotation of single bond,...