BASIC INTRODUCTION OF POLYURETHANE RUBBER
The code (UR) is a polymerization of a polyester (or polyether) and a diisocyanate compound. Its chemical structure is more complex than general elastic polymers. In addition to recurring urethane groups, the molecular chain often also contains ester groups, ether groups, aromatic groups and the like.
The main chain of the UR molecule consists of a flexible segment and a rigid segment; the flexible segment is also called a soft segment and is composed of an oligomer polyol (such as polyester, polyether, polybutadiene, etc.); The hard segment is called a reaction product of a diisocyanate (such as TDI, MDI, etc.) and a small molecular chain extender (such as a diamine and a glycol). Soft segments account for more than hard segments. The hardness of the soft and hard segments is different. The hard segments are more polar and easy to gather together. Many micro-sections are formed in the soft segment phase, which is called micro-phase separation structure. Its physical and mechanical properties and micro-phase The degree of separation has a lot to do with it.
The main chain of the UR molecule has high strength and high elasticity due to the interaction of hydrogen bonds.
Characteristics: It has the advantages of high hardness, good strength, high elasticity, high wear resistance, tear resistance, aging resistance, ozone resistance, radiation resistance and good electrical conductivity. It is unmatched by ordinary rubber.
Post time: Sep-02-2019